Colorectal cancer

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Colorectal cancer



Colorectal cancer


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USMLE® Step 1 questions

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High Yield Notes

18 pages


Colorectal cancer

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USMLE® Step 1 style questions USMLE

of complete

A 55-year-old man is scheduled to undergo a routine screening colonoscopy for colorectal cancer. He does not have any abdominal pain, changes in bowel habits, unintentional weight loss, or noticeable blood in the stool. Past medical history is noncontributory. He has no family history of cancers. Colonoscopy is performed, which reveals a few polyps in the colon. The polyps are biopsied and examined for abnormal histology. Which of the following histological subtypes is at the highest risk for malignant transformation? 

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colorectal p. 398


colorectal cancer p. 397

APC gene p. 222

colorectal cancer and p. 398


colorectal p. 398

Colon cancer

5-fluorouracil for p. 448

irinotecan/topotecan for p. 448

labs/findings p. 720

metastases of p. 202

oncogenes and p. 222

Staphylococcus gallolyticus and p. 135

tumor suppressor genes and p. 222

Colorectal cancer p. 397

adenomatous polyposis and p. 396

bevacizumab for p. 450

cetuximab for p. 450

incidence/mortality in p. 202

labs/findings p. 721

Lynch syndrome p. 37

molecular pathogenesis of p. 398

therapeutic antibodies p. 120

tumor suppressor genes and p. 222

Exophytic mass (colorectal cancer) p. 397

Geriatric patients

colorectal cancer p. 397


colorectal cancer p. 397

Inflammatory bowel disease (IBD) p. 391

colorectal cancer and p. 397

Iron deficiency anemia p. 425

colorectal cancer p. 397

KRAS gene p. 222

colorectal cancer and p. 398

Nonsteroidal anti-inflammatory drugs (NSAIDs) p. 499

colorectal cancer chemopreventative p. 398


colorectal cancer and p. 397

Streptococcus bovis p. , 135

colon cancer p. 720

colorectal cancer and p. 397

Tumor markers

colorectal cancer p. 397

Weight loss

colorectal cancer p. 397


Colorectal carcinoma, also known as colon cancer, is when malignant or cancerous cells arise in the large intestines, which includes the colon and rectum.

It is the most common type of cancer of the gastrointestinal tract, and a major cause of death and disease around the world.

The large intestine is found in the abdominal cavity, which can be thought of as having two spaces - the intraperitoneal space and the retroperitoneal space.

The intraperitoneal space contains the first part of the duodenum, all of the small intestines, the transverse colon, sigmoid colon, and the rectum; the retroperitoneal space contains the distal duodenum, ascending colon, descending colon, and anal canal.

So the large intestines essentially weave back and forth between the intraperitoneal and retroperitoneal spaces.

Now, the walls of the gastrointestinal tract are composed of four layers. The outermost layer is the called serosa for the intraperitoneal parts, and the adventitia for the retroperitoneal parts.

Next is the muscular layer, which contracts to move food through the bowel.

After that is the submucosa, which consists of a dense layer of tissue that contains blood vessels, lymphatics, and nerves.


  1. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  2. "Robbins Basic Pathology" Elsevier (2017)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
  5. "Current and future role of genetic screening in gynecologic malignancies" American Journal of Obstetrics and Gynecology (2017)
  6. "Metastatic Carcinoma Occurring in a Gastric Hyperplastic Polyp Mimicking Primary Gastric Cancer: The First Reported Case" Case Reports in Pathology (2014)
  7. "Mutation Rate in Human Microsatellites: Influence of the Structure and Length of the Tandem Repeat" The American Journal of Human Genetics (1998)

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