THE SPECTRUM OF CHRONIC LYMPHOPROLIFERATIVE DISORDERS IN CHINESE PEOPLE - AN ANALYSIS OF 64 CASES

Background. Chronic lymphoproliferative disorders are considered rare in Oriental patients and are thought to constitute only 2% of all leuk emias in these patients, compared to 20-30% in Western patients. We co nducted a retrospective analysis of Chinese patients with chronic lymp hoproliferative disorders to define the frequency and spectrum of thes e disorders. Methods. A consecutive series of Chinese patients with le ukemia and lymphoproliferative disorders seen at two regional hospital s in Hong Kong were analyzed retrospectively. The diagnosis of chronic lymphoproliferative disorders was based on morphologic and immunologi c criteria proposed by the French-American-British Cooperative Study G roup. Results. Sixty-four Chinese patients with chronic lymphoprolifer ative disorders were identified, and these patients constituted 19% of a total of 342 cases of leukemia diagnosed in 3 years. Chronic lympho cytic leukemia was the most common form, occurring at a frequency of 1 2.5% of all leukemias. The clinicopathologic features of these patient s were similar to those of Western patients, except that Chinese patie nts tended to present with more advanced (Rai's Stages III and IV; Bin et's Stage C) and bulky (splenomegaly >9 cm) disease, and expressed X light chain about six times more frequently. Other chronic lymphoproli ferative disorders identified in this study included prolymphocytic le ukemia, mantle zone lymphoma, hairy cell leukemia, splenic lymphoma wi th villous lymphocytes, large granular lymphocyte leukemia, and Sezary syndrome, The authors did not identify any case of human T-cell lymph otropic virus-I-related lymphoproliferative disorders within the study period. Conclusion. In addition to providing the frequencies of vario us chronic lymphoproliferative disorders in southern Chinese people, t his study also showed that these disorders no longer should be conside red rare in this population. Inherent biologic differences between lym phoproliferative disorders in Chinese and Western patients also may ex ist.