A CASE OF PRIMARY MALIGNANT LYMPHOMA PRESENTING RAPID MORPHOLOGICAL CHANGES IN A RELATIVELY SHORT PERIOD

Abstract

A rare case of primary malignant lymphoma of the rectum presenting rapid morphological changes observed by sequential endoscopic studies is reported. A 46-year-old female complaining of vague epigastric pain was diagnosed as having a rectal flat-elevated varices-like submucosal tumor and seropositive for HTLV-1 antibody. Approximately 3 months after the initial endoscopy, she complained of bloody stools. The second endoscopy showed the lesion seen previously growing to a protruded tumor with reddish erosion. Biopsy was negative for malignancy. Two weeks later, the third endoscopy showed a loburated enlarged tumor. Biopsy revealed malignant lymphoma. One more week later, the forth endoscopy showed the lesion protruded more sharply from the surrounding mucosa with a central ulcer. Abdominoperineal excision of the rectum with R2 lymph node dissection was performed on Feb. 15, 1991. Surgical specimens showed a lobular protuberant submucosal tumor. Histopathological study showed a follicular lymphoma, medium-sized cell type accoording to LSG classification. Immunostaining of the frozen sections showed positive for B-cell markers and producing monoclonal IgM lambda-chain. Involvement of the regional lymph nodes and distant metastasis were not identified. Postoperative chemotherapy and irradiation for the involved field were done for suspicion of residual tumor cells at the surgical stump. The patient is well free from disease for 20 months after surgery. With regard to family history, her husband and mother-in-law with whom she had been live for nearly 20 years also died of malignant lymphoma of the stomach and tonsil, respectively. The familial clustering of this disease and seropositiveness of HTLV-1 antibody suggests an infectious agent and/or environmental factor may play a role in the etiology of malignant lymphoma.