Colorectal Cancer Prevention in Lung Transplant Recipients: The Need for an Enhanced Surveillance Protocol

BACKGROUND: Solid organ transplant recipients are at increased risk for noncutaneous neoplasms, including colorectal cancer (CRC). We evaluated precancerous lesions detected by post-transplant surveillance colonoscopy to infer the rate at which new adenomas develop in this population. STUDY DESIGN: We reviewed all patients who underwent lung transplant between January 2013 and August 2017 at our institution. Those with post-transplant survival <1 year, personal history of CRC, previous lung transplant, and lack of pretransplant colonoscopy were excluded. RESULTS: During the study period, 411 patients underwent lung transplant; 237 met inclusion criteria. Median age at transplant was 63.6 (interquartile range [IQR] 59.2-68.3) years. Most recipients were immunosuppressed with a combination of prednisone, tacrolimus, and mycophenolate mofetil. At least 1 adenoma was found in 92 patients (38.8%) pretransplant and in 118 patients (49.8%) from 1 to 5 years post-transplant, with 68.6% identified at 1 year. Most adenomas were identified proximal to the splenic flexure. Multiple (≥3) adenomas were found in 31.4% of positive colonoscopies. Within 5 years after transplant, patients with a positive pretransplant colonoscopy had significantly more positive post-transplant colonoscopies than patients with a negative pretransplant colonoscopy (63.0% vs 41.4%, p < 0.001). No de novo CRC was identified. CONCLUSIONS: Lung transplant recipients have a significantly higher risk of adenoma formation than average-risk adults (25%–30% national detection rate). This increase occurs in the early post-transplant period (within 3 years). An enhanced CRC surveillance protocol for lung transplant recipients is needed.