CHAPTER 18: Gastroenterology and Hepatology

EVALUATION

The gastroenterology (GI) and hepatology evaluation pre- and post-renal transplantation focuses on three key areas:

• Age-appropriate screening of asymptomatic individuals for colon and rectal cancer

• Evaluation and management of benign conditions that may cause complications posttransplantation

• Diagnosis and management of apparently asymptomatic liver disease, particularly hepatitis B, hepatitis C, and cirrhosis

Pretransplant Colon Cancer Screening

The lifetime risk of colon cancer is approximately 5% in the general Western population.¹ Most of these cancers are believed to arise from precancerous polyps, which can be found in up to 20% of average-risk individuals by the age of 50 years.² Recent guidelines stress the importance of identification of these premalignant lesions, the removal of which markedly decreases the subsequent risk of colon cancer.^3–5 The most recent U.S. Multi-Society Task Force Recommendations have reinforced the recommendation for colonoscopy as the preferred cancer prevention strategy, in contrast to cancer detection alternatives such as fecal hemoccult testing (hemoccult or fecal immunohistochemical) or the newer stool deoxyribonucleic acid (DNA) tests.⁶ Notably, the guidelines continue to stress the specific recommendation for colonoscopy as the method of choice for those in high-risk populations (e.g., family history of colon cancer, personal history of precancerous polyps). As before, the guidelines recommend initial screening at 45 years in the African American population. It is also worth noting that the American Cancer Society has recently published their guidelines and recommend 45 years as the initial screening age for the entire population.⁷

• Colon cancer screening in the general population is associated with decreased cancer rates and improved survival.

• Colon cancer screening is generally recommended to begin at age 50 years, with 45 years appropriate in the African American population.

• Screening modalities in the average-risk population range from fecal hemoccult testing to colonoscopy.

• Screening in high-risk populations should be performed with colonoscopy.

• We recommend age- and disease risk–appropriate screening with colonoscopy prior to transplantation.

Posttransplant Colon Cancer Screening

Posttransplant immunosuppression is associated with an overall increased risk of malignancies. This increased risk extends to colon cancer. One of the largest studies to date from Engels et al. published in 2011 examined the risk of malignancy associated with solid organ transplantation.⁸ The authors reviewed the U.S. Scientific Registry of 175,732 transplant recipients between the years 1987 and 2008, of which 58.4% were kidney transplants. Among GI malignancies, gallbladder, small intestine, esophageal, and gastric cancer showed increased rates and significantly elevated Standardized Incidence Ratios (SIRs). This was true as well for colon cancer, with an SIR of 1.24. Colon cancer was by far the most common GI malignancy seen in the posttransplant population, with the number of cases exceeding the combined total of all other GI malignancies. Similar results were noted by Collett et al.’s transplant registry analysis from the United Kingdom.⁹ Of the 37,617 transplanted patients ...