Endometriosis of the bowel with lymph node involvement. A report of three cases and review of the literature.

Three cases of endometriosis of the bowel with lymph node involvement were studied. Histologically, endometriotic glands with typical stroma were recognized throughout the intestinal wall, from the subserosal tissue to the mucosa. Foci of endometriosis were found in a number of pericolic lymph nodes occupying the subcapsular area or the cortex. The cytological smears were cellular, composed of large sheets of mucous columnar cells of intestinal origin, mixed with groups of recognizable endometrial cells and smaller spindly cells of endometrial stroma. Immunohistochemically, endometriotic cells showed positivity for cytokeratin and EMA, and they retained immunoreactivity for estrogen and progesteron in the intestinal lesions, as well as in the lymph nodes. Lymph nodal endometriosis was disclosed in two out of three cases only by multistep section examination of the pericolic lymph nodes, previously reported as negative for this feature.