R. C. Graham1, O. Afolabi1, J. A. Fridell1, C. A. Kubal1, B. Ekser1, R. S. Mangus1 1Indiana University School Of Medicine,Transplant Division, Department Of Surgery,Indianapolis, IN, USA
Introduction:
Solid organ transplant patients are at an increased risk for de-novo malignancies. Based upon existing literature, it is unclear if these patients have an increased risk of colorectal cancer (CRC) compared to the general population. This study reviews the reports for the required pre-transplant colonoscopy for a large number of liver transplant patients, and then assesses the risk of CRC and other cancers post-transplant.
Methods:
The records of all adult patients undergoing liver transplant (LT) at a single center over a 15 year period were reviewed. The protocol for CRC screening at our center requires a colonoscopy within 3 years of listing for LT. There is no specific post-transplant screening protocol, other than the standard of care for the community. Finding of advanced adenomas (polyps with villous histology, serrated histology, or dysplasia) and colon carcinoma are reported as events. Colonoscopy and pathology reports were reviewed for all patients included in the analysis.
Results:
There were 1685 liver transplants performed during the study period, with 1431 having a pre-transplant colonoscopy report available for review (85%). The median time from colonoscopy to transplant was 9 months. Median follow up was 69 months (minimum 12 months) post- transplant. Of those with available colonoscopy reports, 608 patients had a polyp identified (42%), of which 493 were biopsied with an available pathology report (81%). Of the biopsied polyps, 3 were cancerous (0.2% of all patients, 0.5% of patients with a polyp) and 38 were pre-cancerous (2% of all patients, 6% of patients with a polyp). Among all patients there were 9 individuals who developed post-LT CRC (0.5%). Of these 9 CRC patients, 3 had an abnormal colonoscopy, one with hyperplastic polyps, one with tubular adenomas, and one with a combination of hyperplastic polyps, tubular adenomas, and tubulovillous adenoma; only the last of these three was considered pre-cancerous. Of the 38 patients with pre-cancerous polyps, one developed CRC in the follow up period (3%). There were 9 of the 38 (24%) patients with precancerous polyps who developed other cancers post-transplant including skin (5), breast (1), lung (1), bladder (1), and sarcoma (1). This compares to 16% of patients developing any non-HCC post-transplant cancer.
Conclusion:
These results suggest that screening colonoscopy prior to transplant is effective for exclusion of patients at high-risk for developing CRC post-transplant. Additionally, patients with pre-cancerous colon lesions appear to be at increased risk of developing other cancers post-transplant, but not CRC.