CD34음성 비아세포성 성숙골수계 세포에서 비정상적인 N-CAM (CD56)항원 발현을 보인 만성골수성백혈병 1예

Abstract

The CD56 antigen is a cell adhesion molecule and its expression on tumor cells is thought to play a role in CD56-positive lymphomas and leukemias with unusual sites of involvement. As to chronic myelogenous leukemia (CML) and related blastic crisis, CD56 expression is not generally considered as a part of the CML phenotype and has rarely been reported in CML and other chronic myelopro￢liferative dirsorders (CMPD). We reported a case of CML expressing the CD56 antigen on the CD34￢negative myeloid cells presented with extramedullary granulocytic sarcoma and examined the CD56 reactivity on bone marrow biopsy sections in 9 patients with CMPD. To assess the abnormal expres￢sion of the CD56 antigen on myeloid and progenitor cells from CMPD, immunohistochemical staining and flow cytometric analysis were performed on bone marrow biopsy sections and aspirate speci￢mens, respectively. Of nine patients with CMPD, a case of CML in blastic crisis with extramedullary granulocytic sarcoma showed an abnormal expression of CD56 on CD34-negative myeloid cells. The expression of CD56 on CML myeloid elements seems to represent an aberrant phenomenon that could affect the pattern of tumor cell dissemination.