Hodgkin's lymphoma rectosigmoid in a patient with ulcerative colitis on long-term azathioprine therapy.

Hodgkin's lymphoma complicating chronic ulcerative colitis is extremely rare. We report a case of extranodal Hodgkin's lymphoma involving rectosigmoid in a patient of chronic ulcerative colitis on long-term azathioprine. A 67-year-old man presented with extensive ulcerative colitis, on follow-up since September 2005. He received long-term steroids, mesalamine and azathioprine. Serial surveillance colonoscopic examinations and colonic biopsies were performed. Surveillance colonoscopy performed 8 years after the onset of disease showed multiple deep ulcers and nodular masses involving the rectum and sigmoid colon. Histological examination of rectosigmoid biopsies showed classic Hodgkin's disease. Azathioprine was withdrawn. He received mechlorethamine, vincristine, procarbazine and prednisone (MOPP) chemotherapy protocol and was planned for total colectomy in follow-up. We believe patients with ulcerative colitis on long-term azathioprine should be on vigil for development of lymphomas by protocol surveillance colonoscopic examinations and biopsies. The risk of lymphoma in such patients is small and outweighs the benefits of long-term azathioprine therapy.