NMS. Casos Clínicos

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Chapter 8 ♦ Lower Gastrointestinal Disorders

MALIGNANT DISORDERS OF THE COLON, RECTUM, AND ANUS

Case 8.18 Screening for Colorectal Cancer

A 40-year-old is concerned about colorectal cancer. The patient wants to know your recommendations for screening for colorectal cancer.

Q: What do you tell him? A: The American Cancer Society (ACS) recommends that people at average risk of colorec- tal cancer start regular screening at age 45. Screening is aimed at detecting cancers that are asymptomatic . Obviously, symptomatic patients should undergo evaluation with an accepted routine, usually including colonoscopy. Screening methods include the following: ◆ ◆ Stool-based tests ◆ ◆ Highly sensitive fecal immunochemical test (FIT) every year ◆ ◆ Highly sensitive guaiac-based fecal occult blood test (gFOBT) every year ◆ ◆ Multitargeted stool DNA test (mt-sDNA) every 3 years ◆ ◆ Flexible sigmoidoscopy to look at the interior walls of the rectum. Note this test does not screen the whole colon. ◆ ◆ Colonoscopy to look at the interior walls of the rectum and the entire colon. Colonoscopy can be used as a screening test and as a follow-up diagnostic tool when the results of another screening test are positive. ◆ ◆ CT colonography (virtual colonoscopy) does not require sedation, does give radiation, and does not allow for biopsy of an abnormality. Detailed practice guidelines for colorectal cancer endoscopic surveillance are available, for example, from the US Multi-Society Task Force on Colorectal Cancer.

Table 8-3: Signs and Symptoms of Left-Sided and Right-Sided Lesions Right Colon (%) Left Colon (%) Sigmoid Colon (%) SAMPLE Rectum (%) Pain 80 30 30 10 50 10 70 50 15 10 15 20 50 70 5 Bowel complaints 80 Vomiting Bleeding 3 0 70 30 Weight loss Obstruction

30 20 30 10

3 0

Abscess/peritonitis

1 0

2 0

Tenesmus

0

15

Mass

70

50

40

0