Comparative study of collagen deposition in the colon wall of patients operated for sigmoid diverticular disease.

Purpose: To investigate the deposition of collagen in the colon wall of patients with sigmoid diverticulitis.

Methods: Samples of sigmoid tissue from 15 patients (disease group), seven men and eight women aged 37-77 years who underwent surgery for the treatment of diverticulitis, were selected. For the control group, specimens from five patients, three men and two women aged 19-58 years undergoing emergency surgery for sigmoid trauma were selected.

Emperipolesis in a case of B-cell lymphoma: a rare phenomenon outside of Rosai-Dorfman disease.

We describe a case of a diffuse large B-cell lymphoma with extensive emperipolesis phenomenon. Light microscopy revealed numerous CD68-positive/S-100-negative histiocytes containing viable neoplastic hematopoietic cells in their cytoplasm. Electron microscopy confirmed these findings.