UWorld Qbank + Images 2022 PDF | Step 1 | Clean Version |Free Download | June 2022

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UWorld Qbank + Images 2022 PDF | Step 1 | Clean Version |Free Download | June 2022

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Biochemistry

Biostatistics and Epidemiology

Cardiovascular System

Dermatology

Ear, Nose & Throat (ENT)

Endocrine, Diabetes and Metabolic

Female Reproductive System

Gastrointestinal & Nutrition

Genetics

Hematology & Oncology

Immunology

Male Reproductive System

Microbiology

Miscellaneous

Nervous System

Ophthalmology

Pathology

Pharmacology

Poisoning and Environmental Exposure

Pregnancy, Childbirth & Puerperiu m

Pulmonary & Critical Care

Biostatistics review

Psychiatric, Behavioral & Substance Abuse

Renal, Urinary System & Electrolytes

Social Sciences, Ethics, Legal and Professional

 UWorld Qbank + Images 2021 PDF | Step 1 | Clean Version |Free Download | June 2021

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UWorld Qbank + Images 2021 PDF | Step 1 | Clean Version |Free Download | June 2021

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Biochemistry

Biostatistics and Epidemiology

Cardiovascular System

Dermatology

Ear, Nose & Throat (ENT)

Endocrine, Diabetes and Metabolic

Female Reproductive System

Gastrointestinal & Nutrition

Genetics

Hematology & Oncology

Immunology

Male Reproductive System

Microbiology

Miscellaneous

Nervous System

Ophthalmology

Pathology

Pharmacology

Poisoning and Environmental Exposure

Pregnancy, Childbirth & Puerperiu m

Pulmonary & Critical Care

Biostatistics review

Psychiatric, Behavioral & Substance

Abuse

Renal, Urinary System & Electrolytes

Social Sciences, Ethics, Legal and Professional

UWorld Images

Fundamentals of Pathology Pathoma 2021 PDF FREE Download [Direct Link]

 Fundamentals of Pathology Pathoma 2021 PDF FREE Download [Direct Link]

Fundamentals of Pathology Pathoma PDF 2021 or just Pathoma is the most popular pathology review book among medical students in the United States and all around the world. According to the author of Pathoma, Husain A. Sattar, MD, this book is basically intended to serve as a review for medical students studying in their preclinical years and preparing for competitive board licensing exams such as the USMLE.

This book has been organized keeping in view the major textbooks of pathology and pathophysiology courses and so it is completely well-versed to the syllabus prescribed by medical schools throughout the United States. Today, in this article, we are going to share with you the Fundamentals of Pathology Pathoma 2021 PDF for free download and we hope that all medical students reading our blog would benefit from it.

About The Author:

The author of this book Husain A. Sattar, MD recommends using Fundamentals of Pathology Pathoma 2021 PDF alongside the Pathoma video lectures. As the preface of the book indicates, the publishers have provided ample space for note-taking/writing so that when exam time comes around, these notes would turn out to be very beneficial to the readers.

HUSAIN A. SATTAR, MD

Associate Professor of Pathology Associate Director of Clinical Pathophysiology and Therapeutics Chicago, Illinois

The University of Chicago Pritzker School of Medicine

Table of contents in Fundamentals of Pathology Pathoma 2021 PDF

Below is the complete table of contents presented in the Fundamentals of Pathology Pathoma 2021 PDF:

CHAPTER 1: Growth adaptations, cellular injury, and cell death

CHAPTER 2: Inflammation, inflammatory disorders, and wound healing

CHAPTER 3: Principles of Neoplasia

CHAPTER 4: Hemostasis and related disorders

CHAPTER 5: Red blood cell disorders

CHAPTER 6: White blood cell disorders

CHAPTER 7: Vascular Pathology

CHAPTER 8: Cardiac Pathology

CHAPTER 9: Respiratory Tract Pathology

CHAPTER 10: Gastrointestinal Pathology

CHAPTER 11: Exocrine pancreas, gallbladder, and liver pathology

CHAPTER 12: Kidney and urinary tract pathology

CHAPTER 13: Female genital system and gestational pathology

CHAPTER 14: Male genital system pathology

CHAPTER 15: Endocrine Pathology

CHAPTER 16: Breast Pathology

CHAPTER 17: Central Nervous System Pathology

CHAPTER 18: Musculoskeletal Pathology

CHAPTER 19: Skin Pathology

We believe this would be enough for an introduction to the Fundamentals of Pathology Pathoma 2021.

                                   Download PDF

USING THIS BOOK:

This work is intended as a review for students during their preclinical years and while preparing for examinations, such as the USMLI". To this effect, the organization of this book follows that of most primary lexts in the field and parallels the syllabus used in pathophysiology courses in medical schools throughout the United States. Ample space is provided for students to make notes during course study and while viewing the online videos that cover each section of the text (www.pathoma.com),

We recommend that students use Fundamentals of Pathology during their medical courses, taking notes in the margin as pertinent topics are covered. When exam time comes around, these notes will likely be invaluable.

For examination preparation, we suggest students read the material first, then listen to the online lecture, and then reread the material to develop a solid grasp of each topic. One should not become disheartened if they are not able to retain all the information contained herein. This deceptively slim volume covers a tremendous amount of material, and repetition will be a key aid as you progress in your studies.

An effort has been made to emphasize concepts and principles over random facts, the forest rather than the trees. Attention to the same by the student will provide a deeper, more meaningful understanding of human disease. We must always remind ourselves that ultimately our goal is to learn, to share, and to serve. Fundamentals of Pathology was developed with this goal in mind.

Husain A. Sattar, MD Chicago, Illinois

ACKNOWLEDGMENTS:

This work would not have been possible without the support and encouragement of those around me. To begin with. I would like to acknowledge Shaykh Zulfiqar Ahmad, whose clear vision has guided me to horizons I would never have known. My family is to be acknowledged for their limitless sacrifice, in particular the constant encouragement and support of my wife Amina, who has proved through the years to be the wind under my wings. Thomas Kraus, MD and Aliya Husain, MD (both Professors of Pathology at the University of Chicago) deserve particular mention for their valuable advice and guiding vision, both in the development of this book as well as my career. Special thanks to the multiple reviewers at medical centers throughout the country for their critical comments, in particular Mir Basharath Alikhan, MD (Pathology resident, University of Chicago) and Joshua T.B. Williams (Class of 2013, Pritzker School of Medicine, University of Chicago) for their extensive review. Olaf Nelson (Chinook Design, Inc.) is to be commended for his excellent layout and design. Finally, I would be remiss without acknowledging my students, who give meaning to what I do.

First Aid for the USMLE Step1 2023 33rd Edition pdf Free Download

First Aid For USMLE Step 1 2023 33rd Edition.

First Aid for the USMLE Step1 2023 33rd Edition pdf Free Download

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                                    Size: 258.86

How to Use This Book:

CONGRATULATIONS: You now possess the book that has guided nearly two million students to USMLE success 

for over 30 years. With appropriate care, the binding should last the useful life of the book. Keep in mind that putting 

excessive flattening pressure on any binding will accelerate its failure. If you purchased a book that you believe 

is defective, please immediately return it to the place of purchase. If you encounter ongoing issues, you can also 

contact Customer Service at our publisher, McGraw Hill.

START EARLY: Use this book as early as possible while learning the basic medical sciences. The first semester of 

your first year is not too early! Devise a study plan by reading Section I: Guide to Efficient Exam Preparation, and 

make an early decision on resources to use by checking Section IV: Top-Rated Review Resources. Note that First Aid 

is neither a textbook nor a comprehensive review book, and it is not a panacea for inadequate preparation. 

CONSIDER FIRST AID YOUR ANNOTATION HUB: Annotate this book with material from other resources, 

such as class notes or comprehensive textbooks. This will keep all the high-yield information you need in one place. 

Other tips on keeping yourself organized:

ƒ For best results, use fine-tipped ballpoint pens (eg, BIC Pro+, Uni-Ball Jetstream Sports, Pilot Drawing Pen, 

Zebra F-301). If you like gel pens, try Pentel Slicci, and for markers that dry almost immediately, consider 

Staedtler Triplus Fineliner, Pilot Drawing Pen, and Sharpies.

ƒ Consider using pens with different colors of ink to indicate different sources of information (eg, blue for 

USMLE-Rx Step 1 Qmax, green for UWorld Step 1 Qbank, red for Rx Bricks).

ƒ Choose highlighters that are bright and dry quickly to minimize smudging and bleeding through the page 

(eg, Tombow Kei Coat, Sharpie Gel).

ƒ Many students de-spine their book and get it 3-hole-punched. This will allow you to insert materials from other 

sources, including curricular materials. 

INTEGRATE STUDY WITH CASES, FLASH CARDS, AND QUESTIONS: To broaden your learning strategy, 

consider integrating your First Aid study with case-based reviews (eg, First Aid Cases for the USMLE Step 1), flash 

cards (eg, USMLE-Rx Step 1 Flash Facts), and practice questions (eg, the USMLE-Rx Step 1 Qmax). Read the 

chapter in the book, then test your comprehension by using cases, flash cards, and questions that cover the same 

topics. Maintain access to more comprehensive resources (eg, ScholarRx Bricks and USMLE-Rx Step 1 Express 

videos) for deeper review as needed.

PRIME YOUR MEMORY: Return to your annotated Sections II and III several days before taking the USMLE 

Step 1. The book can serve as a useful way of retaining key associations and keeping high-yield facts fresh in your 

memory just prior to the exam. The Rapid Review section includes high-yield topics to help guide your studying.

CONTRIBUTE TO FIRST AID: Reviewing the book immediately after your exam can help us improve the next 

edition. Decide what was truly high and low yield and send us your comments. Feel free to send us scanned images 

from your annotated First Aid book as additional support. Of course, always remember that all examinees are under 

agreement with the NBME to not disclose the specific details of copyrighted test material.

Contents:

Contributing Authors vii

Associate Authors viii

Faculty Advisors ix

Preface xi

Special Acknowledgments xii

General Acknowledgments xiii

How to Contribute xv

How to Use This Book xvii

Selected USMLE Laboratory Values xviii

First Aid Checklist for the USMLE Step 1 xx

Preface

With the 33rd edition of First Aid for the USMLE Step 1 we continue our commitment to providing students with 

the most useful and up-to-date preparation guide for this exam. This edition represents an outstanding revision in 

many ways, including:

ƒ 73 entirely new or heavily revised high-yield topics reflecting evolving trends in the USMLE Step 1. 

ƒ Extensive text revisions, new mnemonics, clarifications, and corrections curated by a team of 19 medical student 

and resident physician authors who excelled on their Step 1 examinations, and verified by a team of expert 

faculty advisors and nationally recognized USMLE instructors. 

ƒ Updated with 148 new and revised diagrams and illustrations as part of our ongoing collaboration with 

USMLE-Rx and ScholarRx (MedIQ Learning, LLC). 

ƒ Updated with 159 new and revised photos to help visualize various disorders, descriptive findings, and basic 

science concepts. Additionally, revised imaging photos have been labeled and optimized to show both normal 

anatomy and pathologic findings. 

ƒ Updated exam preparation advice for the current pass/fail scoring system of the USMLE Step 1, and Step 1 

blueprint changes. 

ƒ Updated photos of patients and pathologies to include a variety of skin colors to better depict real-world 

presentations. 

ƒ Revised pharmacology sections to include only those drugs currently approved for the US market.

ƒ Improved organization and integration of text, illustrations, clinical images, and tables throughout for focused 

review of high-yield topics.

ƒ Updated Rapid Review section to better reflect exam contents by removing the ‘Classic/Relevant Treatments’ 

section and adding in a ‘Pathophysiology of Important Diseases’ section.

ƒ Revised ratings of current, high-yield review resources, with clear explanations of their relevance to USMLE 

review. Replaced outdated resources with new ones recommended by Step takers.

ƒ Real-time Step 1 updates and corrections can be found exclusively on our blog, www.firstaidteam.com.

We invite students and faculty to share their thoughts and ideas to help us continually improve First Aid for the 

USMLE Step 1 through our blog and collaborative editorial platform. (See How to Contribute, p. xv.)

Louisville Tao Le

Boracay Vikas Bhushan

Baltimore Connie Qiu

Kathmandu Anup Chalise

Athens Panagiotis Kaparaliotis

Atlanta Caroline Coleman

San Francisco Kimberly Kallianos

Special Acknowledgments:

This has been a collaborative project from the start. We gratefully acknowledge the thousands of thoughtful 

comments, corrections, and advice of the many medical students, international medical graduates, and faculty who 

have supported the authors in our continuing development of First Aid for the USMLE Step 1. 

We provide special acknowledgment and thanks to the following individuals who made exemplary contributions 

to this edition through our voting, proofreading, and crowdsourcing platform: Amalia D. Ardeljan, Heather Beyea, 

Avneet Kaur, Yekaterina Khamzina, Alexandra Jan Mrani, and Ajay Ajit Pal Singh.

For support and encouragement throughout the process, we are grateful to Thao Pham, Jinky Flang, and Jonathan 

Kirsch, Esq. Thanks to Louise Petersen for organizing and supporting the project. Thanks to our publisher, McGraw 

Hill, for the valuable assistance of its staff, including Bob Boehringer, Jeffrey Herzich, Christina Thomas, Kristian 

Sanford, and Don Goyette.

We are also very grateful to Dr. Fred Howell and Dr. Robert Cannon of Textensor Ltd for providing us extensive 

customization and support for their powerful Annotate.co collaborative editing platform (www.annotate.co), which 

allows us to efficiently manage thousands of contributions. Thanks to Dr. Richard Usatine and Dr. Kristine Krafts 

for their outstanding image contributions. Thanks also to Jean-Christophe Fournet (www.humpath.com), Dr. Ed 

Uthman, and Dr. Frank Gaillard (www.radiopaedia.org) for generously allowing us to access some of their striking 

photographs.

For exceptional editorial leadership, enormous thanks to Megan Chandler. Special thanks to our indexer, Dr. 

Anne Fifer. We are also grateful to our art manager, Susan Mazik, and illustrators, Stephanie Jones and Rachael 

Joy, for their creative work on the new and updated illustrations. Lastly, tremendous thanks to our compositor, 

GW Inc., especially Anne Banning, Gary Clark, Cindy Geiss, Denise Smith, and Gabby Sullivan.

Louisville Tao Le

Boracay Vikas Bhushan

Baltimore Connie Qiu

Kathmandu Anup Chalise

Athens Panagiotis Kaparaliotis

Atlanta Caroline Coleman

San Francisco Kimberly Kallianos

FAS1_2023_00_Frontmatter.indd 12 11/18

Dengue Fever

Introduction:

Dengue is a febrile illness caused by infection with one of four dengue viruses (DENV) transmitted by Aedes aegypti or Aedes albopictus mosquitoes during the taking of a blood meal. Infection may be asymptomatic or present with a broad range of clinical manifestations including a mild febrile illness to a life-threatening shock syndrome. Numerous viral, host, and vector factors are thought to impact risk of infection, disease, and disease severity.

There are four closely related but serologically distinct DENV types of the genus Flavivirus, called DENV-1, DENV-2, DENV-3, and DENV-4. There is transient cross-protection among the four DENVs, which weakens and disappears over the months following infection; therefore, individuals living in a dengue-endemic area with all types co-circulating are at risk for infection with any and all DENV types.

The Aedes mosquito:

Dengue viruses are transmitted by the bite of an infected female Aedes (subgenus Stegomyia) mosquito. Both males and females require nectar for energy. Females require a blood meal as a source of appropriate protein for egg development. Globally, Aedes aegypti is the predominant highly efficient mosquito vector for dengue infection, but the Asian tiger mosquito, Aedes albopictus, and other Aedes species can also transmit dengue with varying degrees of efficiency.

 Dengue fever :

DF (also known as "break-bone fever") is an acute febrile illness defined by the presence of fever and two or more of the following but not meeting the case definition of DHF. (see 'Dengue hemorrhagic fever' below):

●Headache

●Retro-orbital or ocular pain

●Myalgia and/or bone pain

●Arthralgia

●Rash

●Hemorrhagic manifestations (eg, positive tourniquet test, petechiae, purpura/ecchymosis, epistaxis, gum bleeding, blood in emesis, urine, or stool, or vaginal bleeding)

●Leukopenia   

Dengue hemorrhagic fever :

The cardinal feature of DHF is plasma leakage due to increased vascular permeability as evidenced by hemoconcentration (≥20 percent rise in hematocrit above baseline), pleural effusion, or ascites. DHF is also characterized by fever, thrombocytopenia, and hemorrhagic manifestations (all of which may also occur in the setting of DF). (See 'Dengue fever' above.)

In the setting of DHF, the presence of intense abdominal pain, persistent vomiting, and marked restlessness or lethargy, especially coinciding with defervescence, should alert the clinician to possible impending DSS. (See 'Dengue shock syndrome' below.)

The criteria for DHF comprise a narrow definition that does not encompass all patients with clinically severe or complicated DENV infections.

According to the guidelines, a DHF diagnosis requires all of the following be present:

●Fever or history of acute fever lasting 2 to 7 days, occasionally biphasic

●Hemorrhagic tendencies evidenced by at least one of the following:

•A positive tourniquet test – The tourniquet test is performed by inflating a blood pressure cuff on the upper arm to a point midway between the systolic and diastolic pressures for 5 minutes. A test is considered positive when 10 or more petechiae per 2.5 cm (1 inch) square are observed. The test may be negative or mildly positive during the phase of profound shock. It usually becomes positive, sometimes strongly positive, if the test is conducted after recovery from shock. It is estimated that the tourniquet test is positive in 80 percent of patients with dengue.

•Petechiae, ecchymoses, or purpura.

•Bleeding from the mucosa, gastrointestinal tract, injection sites, or other locations.

•Hematemesis or melena.

●Thrombocytopenia (100,000 cells per mm3 or less) – This number represents a direct count using a phase-contrast microscope (normal is 200,000 to 500,000 per mm3). In practice, for outpatients, an approximate count from a peripheral blood smear is acceptable. In healthy individuals, 4 to 10 platelets per oil-immersion field (100x; the average of the readings from 10 oil-immersion fields is recommended) indicates an adequate platelet count. An average of 3 platelets per oil-immersion field is considered low (ie, 100,000 per mm3).

●Evidence of plasma leakage due to increased vascular permeability manifested by at least one of the following:

•A rise in the hematocrit equal to or greater than 20 percent above average for age, sex, and population.

•A drop in the hematocrit following volume-replacement treatment equal to or greater than 20 percent of baseline.

•Signs of plasma leakage such as pleural effusion, ascites, and hypoproteinemia.

Dengue shock syndrome :

DSS is DHF with marked plasma leakage that leads to circulatory collapse (shock) as evidenced by narrowing pulse pressure or hypotension.

For a diagnosis of DSS, all of the above four criteria for DHF must be present plus evidence of circulatory failure manifested by:

●Rapid and weak pulse.

●Narrow pulse pressure (20 mmHg [2.7 kPa]) or manifested by:

•Hypotension for age – Hypotension is defined to be a systolic pressure 80 mmHg (10.7 kPa) for those less than 5 years of age or 90 mmHg (12.0 kPa) for those greater than or equal to 5 years of age. Note that narrow pulse pressure is observed early in the course of shock, whereas hypotension is observed later or in patients who experience severe bleeding.

•Cold, clammy skin and restlessness.

Dengue without warning signs:

A presumptive diagnosis of dengue infection may be made in the setting of residence in or travel to an endemic area plus fever and two of the following [9]:

●Nausea/vomiting

●Rash

●Headache, eye pain, muscle ache, or joint pain

●Leukopenia

●Positive tourniquet test

Dengue with warning signs :

Dengue with warning signs of severe infection includes dengue infection as defined above in addition to any of the following [9]:

●Abdominal pain or tenderness

●Persistent vomiting

●Clinical fluid accumulation (ascites, pleural effusion)

●Mucosal bleeding

●Lethargy or restlessness

●Hepatomegaly >2 cm

●Increase in hematocrit concurrent with rapid decrease in platelet count

Severe dengue :

Severe DENV infection includes infection with at least one of the following:

●Severe plasma leakage leading to:

•Shock

•Fluid accumulation with respiratory distress

●Severe bleeding (as evaluated by clinician)

●Severe organ involvement:

•Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) ≥1000 units/L

•Impaired consciousness

•Organ failure

Signs and symptoms :

On average, dengue becomes symptomatic after a 4- to 10-day incubation period (range, 3-14 days). Dengue symptoms usually last 2-7 days.

Many individuals with dengue may be asymptomatic. Many patients with dengue experience a prodrome of chills; rash, including erythematous mottling of the skin; and facial flushing, which may last 2-3 days. Children younger than 15 years who have dengue usually have a nonspecific febrile syndrome, which may be accompanied by a maculopapular rash. Dengue should be suspected in individuals who present with high fever (104°F/40°C), retro-orbital headache, muscle and joint pain, nausea, lymphadenopathy, vomiting, and rash and who have traveled within 2 weeks of symptom onset to an area where appropriate vectors are present and dengue transmission may be occurring.

Accompanying symptoms in patients with dengue may include any of the following:

Fever

Headache

Retro-orbital pain

Severe myalgias: Especially of the lower back, arms, and legs

Arthralgias: Usually of the knees and shoulders

Nausea and vomiting (diarrhea is rare)

Rash: A maculopapular or macular confluent rash over the face, thorax, and flexor surfaces, with islands of skin sparing

Weakness, malaise, and lethargy

Altered taste sensation

Anorexia

Sore throat

Mild hemorrhagic manifestations (eg, petechiae, bleeding gums, epistaxis, menorrhagia, hematuria)

Lymphadenopathy

Diagnosis :

Demonstration of a fourfold or greater change in reciprocal immunoglobulin G (IgG) or IgM antibody titers to 1 or more dengue virus antigens in paired serum samples

Demonstration of dengue virus antigen in autopsy tissue via immunohistochemistry or immunofluorescence or in serum samples via enzyme immunoassay (MAC-ELISA, IgG ELISA, nonstructural protein 1 [NS1] ELISA, EIA)

Detection of viral genomic sequences in autopsy tissue, serum, or cerebral spinal fluid (CSF) samples via reverse-transcriptase polymerase chain reaction (RT-PCR) assay: RT-PCR provides earlier and more specific diagnosis.

Less frequently, isolation of the dengue virus from serum, plasma, leukocytes, or autopsy samples

PREVENTION :

Personal protection from infection

Mosquito repellants — Issues related to personal protection for prevention of mosquito bites are discussed separately. (See "Prevention of arthropod and insect bites: Repellents and other measures".)

Insecticide spraying — Distribution of insecticide-treated curtains was successful in reducing populations of A. aegypti mosquitoes for up to 18 months in several studies and was associated with reduced human and mosquito infections with DENV in one region, although use of the curtains declined with time. Insecticide spraying in response to dengue outbreaks is not highly effective, since A. aegypti mosquitoes frequently breed inside houses.

Vaccine development — Infection with one DENV type provides long-term protection against reinfection with that same type, supporting the feasibility of an effective dengue vaccine. 

Treatment :

No specific treatment for dengue fever exists.

While recovering from dengue fever, drink plenty of fluids. Call your doctor right away if you have any of the following signs and symptoms of dehydration:

Decreased urination

Few or no tears

Dry mouth or lips

Lethargy or confusion

Cold or clammy extremities

The over-the-counter (OTC) drug acetaminophen (Tylenol, others) can help reduce muscle pain and fever. But if you have dengue fever, you should avoid other OTC pain relievers, including aspirin, ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve). These pain relievers can increase the risk of dengue fever bleeding complications.

If you have severe dengue fever, you may need:

Supportive care in a hospital

Intravenous (IV) fluid and electrolyte replacement

Blood pressure monitoring

Transfusion to replace blood loss

Breast Cancer – Causes, Symptoms, Diagnosis & Treatment Options

 

Breast Cancer

Breast cancer is the common term for a set of breast tumor subtypes with distinct molecular and cellular origins and clinical behavior. Most of these are epithelial tumors of ductal or lobular origin (see the image below). Worldwide, breast cancer is the most frequently diagnosed life-threatening cancer in women and the leading cause of cancer death among women.

 Risk Factors for Breast Cancer

Factors that may affect breast cancer risk include the following:

• Age: The strongest risk factor for breast cancer is age. Median age at diagnosis is about 60 years.

• Family history: Having a 1st-degree relative (mother, sister, daughter) with breast cancer doubles or triples risk of developing the cancer, but breast cancer in more distant relatives increases risk only slightly. When ≥ 2 1st-degree relatives have breast cancer, risk may be 5 to 6 times higher.

• Breast cancer gene mutation: About 5 to 10% of women with breast cancer carry a mutation in one of the two known breast cancer genes, BRCA1 or BRCA2. The risk of developing breast cancer by age 80 is about 72% with a BRCA1 mutation and about 69% with a BRCA2 mutation. Women with BRCA1 mutations also have an approximate 44% lifetime risk of developing ovarian cancer; risk among women with BRCA2 mutations is about 17% (3, 4). Women without a family history of breast cancer in at least two 1st-degree relatives are unlikely to carry this mutation and thus do not require screening for BRCA1 and BRCA2 mutations. Men who carry a BRCA mutation have a 1 to 2% lifetime risk of developing breast cancer. The mutations are more common among Ashkenazi Jews. Women with BRCA1 or BRCA2 mutations require closer surveillance or preventive measures, such as screening with both mammography and MRI, taking tamoxifen or raloxifene, or undergoing risk-reducing mastectomy.

• Personal history: Having had in situ or invasive breast cancer increases risk. Risk of developing cancer in the contralateral breast after mastectomy is about 0.5 to 1%/year of follow-up.

• Gynecologic history: Early menarche, late menopause, or late first pregnancy increases risk. Women who have a first pregnancy after age 30 are at higher risk than those who are nulliparous.

• Breast changes: History of a lesion that required a biopsy is associated with a slightly increased risk. Women with multiple breast masses but no histologic confirmation of a high-risk histology should not be considered at high risk. Benign lesions associated with a slightly increased risk of developing invasive breast cancer include complex fibroadenoma, moderate or florid hyperplasia (without atypia), sclerosing adenosis, and papilloma. Risk is about 4 or 5 times higher than average in patients with atypical ductal or lobular hyperplasia and about 10 times higher if they have a family history of invasive breast cancer in a 1st-degree relative. Increased breast density seen on screening mammography is associated with a 1.2- to 2.1-fold increased risk of breast cancer.

• Lobular carcinoma in situ (LCIS): Having LCIS increases the risk of developing invasive carcinoma in either breast by about 7 to 12 times ; invasive carcinoma develops in about 1 to 2% of patients with LCIS annually.

• Use of oral contraceptives: Study results vary regarding the use of oral contraceptives and risk of breast cancer. Some studies have found a small increased risk in current or recent users.

• Hormone therapy: Menopausal hormone (estrogen plus a progestin) therapy appears to increase risk modestly after only 3 years of use. After 5 years of use, the increased risk is about 7 or 8 more cases per 10,000 women for each year of use (about a 24% increase in relative risk). Use of estrogen alone does not appear to increase risk of breast cancer (as reported in the Women's Health Initiative). Selective estrogen-receptor modulators (eg, raloxifene) reduce the risk of developing breast cancer.

• Radiation therapy: Exposure to radiation therapy before age 30 increases risk. Mantle-field radiation therapy for Hodgkin lymphoma about quadruples risk of breast cancer over the next 20 to 30 years.

• Diet: Diet may contribute to development or growth of breast cancers, but conclusive evidence about the effect of a particular diet (eg, one high in fats) is lacking. Obese postmenopausal women are at increased risk, but there is no evidence that dietary modification reduces risk. For obese women who are menstruating later than normal, risk may be decreased.

• Lifestyle factors: Smoking and alcohol may contribute to a higher risk of breast cancer. Women are counseled to stop smoking and to reduce alcohol consumption. In epidemiologic studies, alcohol intake is associated with a higher risk of breast cancer; however, causality is difficult to establish. The American Cancer Society recommends no more than one alcoholic drink a day for women. 

• Pathology of Breast Cancer : 

• Most breast cancers are epithelial tumors that develop from cells lining ducts or lobules; less common are nonepithelial cancers of the supporting stroma (eg, angiosarcoma, primary stromal sarcomas, phyllodes tumor).
• Cancers are divided into carcinoma in situ and invasive cancer.

Carcinoma in situ is proliferation of cancer cells within ducts or lobules and without invasion of stromal tissue. There are 2 types:

Ductal carcinoma in situ (DCIS): About 85% of carcinoma in situ are this type. DCIS is usually detected only by mammography. It may involve a small or wide area of the breast; if a wide area is involved, microscopic invasive foci may develop over time.

Lobular carcinoma in situ (LCIS): LCIS is often multifocal and bilateral. There are 2 types: classic and pleomorphic. Classic LCIS is not malignant but increases risk of developing invasive carcinoma in either breast. This nonpalpable lesion is usually detected via biopsy; it is rarely visualized with mammography. Pleomorphic LCIS behaves more like DCIS; it should be excised to negative margins.

Invasive carcinoma is primarily adenocarcinoma. About 80% is the infiltrating ductal type; most of the remaining cases are infiltrating lobular.

Rare types include medullary, mucinous, metaplastic, and tubular carcinomas. Mucinous carcinoma tends to develop in older women and be slow growing. Women with most of these rare types of breast cancer have a much better prognosis than women with other types of invasive breast cancer. However, the prognosis for women with metaplastic breast cancer is significantly worse than other types of ductal breast cancer.

Inflammatory breast cancer is a fast-growing, particularly aggressive, and often fatal cancer. Cancer cells block the lymphatic vessels in breast skin; as a result, the breast appears inflamed, and the skin appears thickened, resembling orange peel (peau d’orange). Usually, inflammatory breast cancer spreads to the lymph nodes in the armpit. The lymph nodes feel like hard lumps. However, often no mass is felt in the breast itself because this cancer is dispersed throughout the breast.

Pathophysiology of Breast Cancer:

Breast cancer invades locally and spreads through the regional lymph nodes, bloodstream, or both. Metastatic breast cancer may affect almost any organ in the body—most commonly, lungs, liver, bone, brain, and skin. Most skin metastases occur near the site of breast surgery; scalp metastases are uncommon.

Hormone receptors:

Estrogen and progesterone receptors, present in some breast cancers, are nuclear hormone receptors that promote DNA replication and cell division when the appropriate hormones bind to them. Thus, drugs that block these receptors may be useful in treating tumors with the receptors. About two thirds of postmenopausal patients with cancer have an estrogen receptor–positive (ER+) tumor. Incidence of ER+ tumors is lower among premenopausal patients.

Another cellular receptor is human epidermal growth factor receptor 2 (HER2; also called HER2/neu or ErbB2); its presence correlates with a poorer prognosis at any given stage of cancer. In about 20% of patients with breast cancer, HER2 receptors are overexpressed. Drugs that block these receptors are part of standard treatment for these patients.

Breast cancer genes:

BRCA1 and BRCA2 gene mutations increase the risk of developing breast cancer to 70%. Prophylactic bilateral mastectomy reduces the risk of breast cancer by 90% and should be offered to women with a BRCA mutation. Other genetic mutations that increase the risk of developing breast cancer include mutations in CHEK2, PALB2, ATM, RAD51C, RAD51D, BARD1, and TP53, which are usually included in panel genetic testing.

Symptoms and Signs of Breast Cancer

Many breast cancers are discovered as a mass by the patient or during routine physical examination or mammography. Infrequently, the presenting symptom is breast enlargement or a nondescript thickening of the breast. Breast pain may be present but is almost never the sole presenting symptom of breast cancer.

Some types of breast cancer manifest with notable skin changes:

Paget disease of the nipple is associated with an underlying in situ or invasive carcinoma and manifests as skin changes, including erythema, crusting, scaling, and discharge; these changes usually appear so benign that the patient ignores them, delaying diagnosis for a year or more. About 50% of patients with Paget disease of the nipple have a palpable mass at presentation.

Inflammatory breast cancer manifests as erythema and enlargement of the breast, often without a mass, and skin may be discolored or appear thickened, resembling orange peel (peau d’orange). A nipple discharge is common.

A few patients with breast cancer present with signs of metastatic disease (eg, pathologic fracture, abdominal pain, jaundice, dyspnea).

A common finding during physical examination is asymmetry or a dominant mass—a mass distinctly different from the surrounding breast tissue. Diffuse fibrotic changes in a quadrant of the breast, usually the upper outer quadrant, are more characteristic of benign disorders; a slightly firmer thickening in one breast but not the other may be a sign of cancer.

More advanced breast cancers are characterized by one or more of the following:

Fixation of the mass to the chest wall or to overlying skin

Satellite nodules or ulcers in the skin

Matted or fixed axillary lymph nodes suggest tumor spread, as does supraclavicular or infraclavicular lymphadenopathy.

Change in breast size or shape

Skin dimpling or skin changes

Recent nipple inversion or skin change, or nipple abnormalities

Single-duct discharge, particularly if blood-stained

Axillary lump

    

 

Diagnosis of breast cancer

Breast cancer is often first detected as an abnormality on a mammogram before it is felt by the patient or health care provider.

1.Clinical examination

2.Imaging

3.Needle biopsy

4.Physical examination: The following physical findings should raise concern:

Lump or contour change

Skin tethering

Nipple inversion

Dilated veins

Ulceration

Paget disease

Edema or peau d’orange

Screening

Breast self-examination

Mammography

Ultrasonography

Magnetic resonance imaging

Treatment of Breast Cancer

Surgery

Usually radiation therapy

Systemic therapy: Endocrine therapy, chemotherapy, or both

 West Nile Infections Rising in the US

West Nile virus

West Nile virus (WNV) is a single-stranded RNA virus that causes West Nile fever. It is a member of the family Flaviviridae, from the genus Flavivirus, which also contains the Zika virus, dengue virus, and yellow fever virus. The virus is primarily transmitted by mosquitoes, mostly species of Culex. The primary hosts of WNV are birds, so that the virus remains within a "bird–mosquito–bird" transmission cycle.The virus is genetically related to the Japanese encephalitis family of viruses.

Realm: Riboviria

Kingdom: Orthornavirae

Phylum: Kitrinoviricota

Class: Flasuviricetes

Order: Amarillovirales

Family: Flaviviridae

Genus: Flavivirus

Species: West Nile virus

Several signs are pointing to an impending surge in the number of human cases of West Nile virus in several regions of the United States.

West Nile virus is spread by infected mosquitoes and currently there is no cure or virus-specific treatment. In rare cases, it can be deadly. It can infect humans, birds, horses, and other mammals.

West Nile Virus is the leading cause of mosquito-borne disease in the continental US. And as of August 8, 126 human cases had been identified across 22 states, according to the Centers for Disease Control and Prevention (CDC).

Vicki Kramer, PhD, chief of vector-borne diseases in the California Department of Public Health, said, "Particularly here in California, it's peak risk right now."

She said scientists there are seeing higher mosquito and infected mosquito numbers.

"Peak Risk Right Now"

Dead birds are tested for the virus and by August 4, 181 of the 913 birds tested in California have been positive, three times the total testing positive by this time in 2022.

"Last year at this time, we had 60 positive dead birds out of 817 tested," Kramer said.

Severe flooding and high heat can contribute to the rise in mosquito populations and many parts of the country have seen plenty of both.

One of the ways scientists track infected mosquito patterns in California is by using flocks of strategically placed sentinel chickens.

"Chickens are a mosquito magnet," Kramer said.

Chickens don't get sick with the virus, but they do build antibodies to it. Surveillance teams check their blood every other week to track the virus.

Daniel Pastula, MD, MHS, chief of neuroinfectious diseases and global neurology at the University of Colorado School of Medicine and the Colorado School of Public Health, says the state is watching troubling signs as well.

"The concern this year," Pastula said, "particularly along the Front Range in Colorado, is we've found many more mosquitoes [that are] positive for West Nile earlier in the season compared with other years."

"We're bracing for higher-than-baseline human cases," he said.

Asked about this year's first human case reported in Toronto, Canada, a region with a long winter and low incidence of the virus, he said that provides a further example that people need to be prepared even in climates not known to be mosquito-dense.

He added, however, that climate is only one factor in the severity of the season. Others include birds' immunity and migratory patterns.

Pastula said that fluctuations in temperature and rainfall are rising with climate change and are disrupting normal baseline levels of West Nile.

"That shows we need to be prepared for West Nile virus and other mosquito-borne diseases in any place in North America or really the world. We recently saw malaria cases in the southern United States. It just shows you how dangerous mosquitoes can be."

Avoid Mosquito Bites

Pastula and Kramer list the precautions people can take to protect themselves from West Nile virus:

Limit outdoor exposure particularly at dusk and dawn

Wear protective clothing

Use EPA-approved insect repellent

Repair window screens so mosquitoes can't fly through

Dump and drain standing water on your property and maintain swimming pool

Pastula notes that summer is the time human cases start to mount — typically from July and August to the first hard freeze.

"We have been warning people here up and down the Front Range of Colorado to take prevention very seriously," Pastula said.

He pointed out that 80% who are infected with West Nile will have no symptoms.

About 20% will have flu-like illness — high fever, body and joint aches, rash, diarrhea, or headaches. Symptoms may last for weeks. About 1% of the time, he says, people can get neuroinvasive West Nile.

Pastula explains that the virus can infect the covering of the brain and spinal cord causing meningitis with very high fever, severe headaches, stiff neck, and sensitivity to light.

So far this year, there have been 89 neuroinvasive cases reported nationally, according to the CDC.

With West Nile encephalitis, the virus "can infect the brain itself causing altered mental status, movement disorders, or weakness," Pastula said.

Sometimes it can infect the gray matter of the spinal cord causing a West Nile virus poliomyelitis, which brings polio-like symptoms.

"The West Nile encephalitis and poliomyelitis can cause permanent deficits or even death," he said. "It's uncommon but it's not trivial."

Several vaccine candidates are in development, Pastula says, but none has reached clinical trials. Part of the reason for that, he says, is that scientists must be able to predict the timing of an outbreak.

"We're not really great at predicting outbreaks," he said.

Although the risk for neuroinvasive disease is small, it can be higher in certain groups, he says — those who are over age 60 years or are immunocompromised; those who have diabetes, cancer, or kidney disease; or those who have undergone organ transplants.

Those infected should see a healthcare professional and may be able to get relief with the usual medications for flu-like illness.

Some with severe infection may need to go to the hospital, Pastula said.