ABSTRACT
<p><b>OBJECTIVE</b>To investigate the feasibility of CyclinD1/IgH detection by FISH in diferential diagnosis between mantle cell lymphoma (MCL) and chronic lymphocytic leukeamia (CLL).</p><p><b>METHODS</b>The FISH detection was performed for CyclinD1/IgH fusion gene. A comprehensive analysis was carried out for clinical features, such as age, sex , WBC count and lymphocyte count, the bone marrow morphology and immunohistochemical staining were carried for CyclinD1/IgH.</p><p><b>RESULTS</b>It is often difficult to distinguish MCL from CLL by bone marrow morphology, when the cell morphology was not typical; there was no difference in age, sex, WBC count and lymphocyte count between MCL and CLL groups; 9 out of 52 patients were diagnosed as MCL, and the direction of CyclinD1/IgH by FISH was positive in 7 of 9 MCL, while 3 of the 7 patients were negative by immunohistochemical staining for CyclinD1.</p><p><b>CONCLUSION</b>Detection of CyclinD1/IgH by FISH can be used as a specific and feasible method for differential diagnosis of mantle cell lymphoma from chronic lymphocytic leukeamia.</p>