Review of 51 autopsy cases of patients receiving high-dose chemotherapy followed by bone marrow transplantation revealed a high prevalence of pancreatic ductal and acinar changes compared with control groups. Forty-five percent (23 of 51) of bone marrow transplant cases had squamous metaplasia of the pancreatic ducts compared with 10% of randomly selected control cases. Although squamous metaplasia was more common in bone marrow transplant patients receiving chemotherapy, it was not associated with whole body radiation, allogeneic transplantation, or specific drugs. Squamous metaplasia was more common in patients dying 30 days or more after transplantation. Dilatation of the pancreatic acini was present in 78.4% of transplant cases, 35.0% of control cases, and 50.0% of a group of 12 breast cancer patients treated with conventional doses of chemotherapy without bone marrow transplantation. This lesion was associated with uremia. Oncocytic change of the acinar epithelium was present in 52.9% of transplant cases, no control cases, and 41.7% of breast cancer cases. Squamous metaplasia of the pancreas is common in bone marrow transplant patients receiving high-dose chemotherapy and may be a late manifestation of toxic injury to the ducts. A high prevalence of acinar dilatation was associated with terminal uremia. Oncocytic change of acinar epithelium was associated with chemotherapy.