[Small intestinal plasmacytoid lymphoma. Clinical presentation with acute abdominal pain].

Primary tumors of the small intestine are rare; 15-20% of the cases are extranodal lymphomas from B or T cells. Higher Incidence occurs in patients between 21 and 50 years. The clinical symptoms are pain, intestinal obstruction, diarrhea, bleeding or perforated peritonitis. In high-grade lymphomas, the cells are large and pleomorphic, with immunoblastic and plasmacytoid features, and immunopositive for alpha chain immunoglobulins. We reported the case of a 56-year-old patient presented with abdominal pain associated with intestinal perforation. Resections of a 9-centimetres-long segment in the small intestine was performed, which was covered by purulent plaques, with a perforation of 5 mm, surrounded by a greyish-white thick intestinal wall. It can be observed in the microscopy a proliferation of neoplastic cells arranged diffusely and with frequent mitosis. Large areas of immunoblastic and plasmacytoid configuration were evident. The immunomarcation was consistent with a lymphoma of large cells, immunophenotype B, with plasmacytoid development. We highlighted the clinical presentation like acute abdominal pain and its clinical and pathological characteristics, especially in the plasmacytoid development that should differ of the true plasmocytoma.