PRIMARY GASTRIC CD30 (KI-1)-POSITIVE LARGE-CELL NON-HODGKINS-LYMPHOMAS - A CLINICOPATHOLOGICAL ANALYSIS OF 6 CASES

Background. The CD30/Ki-1 antigen characterizes a series of non-Hodgki n's lymphomas (NHL) predominantly showing anaplastic large cell (ALCL) morphology and frequently involving the skin and other extranodal sit es. In cutaneous large cell lymphomas, the CD30 expression was indicat ed as a favorable prognostic marker independently from cytology, anapl astic versus nonanaplastic. The stomach is the most common site of ext ranodal lymphomas in the adult population, but primary gastric CD30+ l ymphomas have been reported rarely. Methods. The clinical, morphologic , and immunohistochemical features of six cases with primary CD30/Ki-1 + gastric large cell lymphomas were analyzed. Results. The mean age of patients was 64 years with a prevalence of women (M:F ration = 1:2). patients were assigned to Stage IE or IIE. Three of them died of disea se, whereas the others are still alive (mean follow-up, 18 months). Th ree of six cases had ALCL morphology, whereas other cases had centrobl astic, immunoblastic, and high-grade mucosa-associated lymphoid tissue lymphoma. Immunohistochemistry revealed a B-cell phenotype in three o f six cases; a T-cell phenotype in one of six cases; and a null, non-B , non-T phenotype in two of six cases. Conclusions. Within CD30+ prima ry gastric large cell lymphomas, cytology, anaplastic versus nonanapla stic, did not affect clinical presentation and/or prognosis. The survi val rate of the patients studied is in keeping with literature reports regarding prognosis of primary high-grade gastric NHL. The findings s uggest that clinical behavior of this extranodal lymphoma is more clos ely related to clinical symptoms and initial stage of disease than to CD30 expression.