Gastrointestinal lymphonodular hyperplasia and lymphoid polyps of the rectum--a rare coincidence.

Lymphoid polyps of the rectum are rare lesions. We report on an 8 1/2-year-old boy, who presented with hematochezia and abdominal pain. Flexible endoscopy revealed large sessile polyps of the rectum and lymphonodular hyperplasia of the duodenum, terminal ileum und descending colon. One rectal polyp was excised in toto, microscopically it revealed the typical features of a lymphoid polyp. Based on the distinct follicular architecture, the cytomorphology and the immunohistochemical findings of the lymphatic infiltrate we were able to distinguish this lesion from malignant lymphoma. The coincidence of lymphoid polyps and gastrointestinal lymphonodular hyperplasia gives evidence that both entities are different variations of the same benign lymphoproliferative process. Lymphoid polyps of the rectum should be treated by local excision for diagnostic purposes. Immunohistochemical staining of fresh, nonfixed tissue is a useful ancillary technique in distinguishing these benign lesions from lymphoma of mucosa associated lymphoid tissue (MALT-lymphoma).