Non-Hodgkin lymphoma involving stomach and ovary: extending the Krukenberg tumor concept

Abstract

Dear Editor, Krukenberg tumors are carcinomas metastatic to the ovaries with the primary site located in the gastrointestinal tract, usually the stomach. We present the first case of extranodal lymphoma involving exclusively the stomach and right ovary, thus mimicking a Krukenberg tumor. A 61-year-old woman was admitted following a fainting episode associated with passing dark red blood per rectum. There was no relevant past medical or family history and she denied B symptoms. She was only taking atorvastatin for hyperlipidemia. On physical examination, a firm, painless mass was palpated in the hypogastrium. Laboratory investigations were remarkable for iron deficiency anemia (Hb 9.5 g/dl) and a raised serum lactic dehydrogenase level of 745 IU/l (reference range 230–450 IU/l). Upper gastrointestinal tract endoscopy revealed a gastric tumor with a large central ulceration (Fig. 1, top left) near the lowermost part of the greater curvature. Colonoscopy showed diverticula in the sigmoid and small adenomatous polyps in the transverse colon. Computerized tomographic (Fig. 1, top right) and ultrasound scans of the abdomen confirmed the presence of a pelvic tumor measuring 9.5× 11 cm. At exploratory laparotomy, the tumor was shown to arise from the right ovary. There was no associated pelvic lymphadenopathy. Histological examination of endoscopic and open biopsy samples from the gastric and pelvic tumors, respectively, showed diffuse infiltration by largecell non-Hodgkin lymphoma (Fig. 1, bottom left). On immunocytochemistry, the neoplastic cells were positive for CD20 (Fig. 1, bottom right) and BCL-2, frequently positive for MUM1, occasionally positive for BCL-6, negative for CD1, CD3, CD5, CD10, and CD23, and showed lambda light chain monoclonality. Proliferation index was high, with 80% MKI67 positivity. No lymphoepithelial lesions could be seen on staining with the anticytokeratin antibody CAM5.2. Search for Helicobacter pylori in the gastric biopsies (Giemsa stain) was negative. Staging investigations did not detect any lymphadenopathy, and there was no bone marrow or other organ involvement. The diagnosis of diffuse large B cell lymphoma (WHO classification) stage IVE (Ann Arbor classification) was made. To our knowledge, there are no previous reports of lymphoma presenting with synchronous involvement of stomach and ovary, in the absence of other sites of disease. The gastro-ovarian axis is a well-known route of selective tumor spread in cases of gastric adenocarcinoma. Frederick Krukenberg, in 1896, described what he believed to be a peculiar primary ovarian tumor consisting of signet-ring carcinoma cells, mixed with elements resembling fibrosarcoma [1]. In the years following Krukenberg’s original report, it became clear that these tumors are in fact adenocarcinomas involving one or both ovaries, and are almost invariably secondary to carcinomas of the stomach or intestines [2]. The ovarian tumor may become clinically manifest before the gastric primary, which often escapes diagnosis due to its small size [3, 4]. The mode of tumor Ann Hematol (2010) 89:101–102 DOI 10.1007/s00277-009-0770-2