Nivolumab-Induced Immune Mediated Colitis Localized to the Distal Colon: Seven Years Into Therapy.

Nivolumab targets programmed cell death protein 1 (PD-1) and is used in cancer treatment by increasing the immune response. It has rarely been associated with immune-mediated colitis (IMC). We present a 66-year-old man with metastatic lung adenocarcinoma, treated with nivolumab for seven years, who developed tenesmus and mucoid bloody diarrhea.

Isolated Asymptomatic Colonic Plasmacytoma Presenting as a Polyp at Screening Colonoscopy.

Isolated extramedullary plasmacytomas (IEMPs) are rare. Extramedullary plasmacytomas (EMPs) are uncommon and mostly occur in the nasopharynx or upper respiratory tract. EMP involvement of the gastrointestinal tract occurs in approximately 10% of cases, more often in the small bowel than the colon.