Nature and outcomes of the increased incidence of colorectal malignancy after liver transplantation in Australasia.

OBJECTIVES To examine whether incidence of colorectal malignancy is increased in Australasian liver transplant recipients compared with the general population of Australia, and to assess the characteristics and outcomes of colorectal malignancy in this patient group. DESIGN, SETTING AND PATIENTS Data on patients who underwent orthotopic liver transplantation (OLTx) and had a diagnosis of de-novo colorectal malignancy after transplantation during the period 1985-2011 were obtained from the Australia and New Zealand Liver Transplant Registry, and these data were compared with colorectal malignancy data from the Australian Institute of Health and Welfare. MAIN OUTCOME MEASURES Time from OLTx to diagnosis of colorectal malignancy, stage of colorectal malignancy at diagnosis, patient survival, and standardised incidence ratio (SIR) for colorectal malignancy. RESULTS Forty-eight of 3735 recipients (1.3%) were diagnosed with colorectal malignancy at a median of 7.3 years after OLTx. More advanced colorectal malignancy (regional or metastatic disease) was evident at diagnosis in 20 of the 48 patients; these patients tended to be younger than patients with less advanced malignancy (P = 0.01) and diagnosed sooner after OLTx (P = 0.005). Despite treatment predominantly with surgery, 19 of the 48 patients died from the malignancy. The overall SIR for colorectal malignancy liver transplant recipients compared with the general population of Australia was 2.80 (95% CI, 2.06-3.71). CONCLUSIONS The incidence of colorectal malignancy is increased in liver transplant recipients in comparison with the general population. Of concern is the tendency for advanced malignancy to be diagnosed in younger patients. These data highlight the importance of considering whether specific guidelines for colorectal malignancy screening in the Australasian adult liver transplant population are needed.