Clinical analysis of 33 patients with adult T‐cell leukemia (ATL)‐diagnostic criteria and significance of high‐ and low‐risk ATL

The clinical characteristics of 33 patients with adult T‐cell leukemia (ATL) are described. All patients were born and have lived in Miyazaki Prefecture (south‐west of Japan). Because of a wide range of clinical presentations and courses, they were subdivided into 2 groups. In the high‐risk group, patients presented with high white‐cell counts (WBC ≧ 20,000/μl) and over 30% of abnormal lymphoid cells (18 patients) and hypercalcemia with a low percentage of leukemic cells (5 patients). In this group the median survival time was only 3 months despite various modes of treatment. In contrast, patients of the second group exhibited a low percentage of abnormal lymphoid cells (WBC < 20,000/μl and/or leukemic cells < 30%) and had no hypercalcemia (8 patients). Their clinical course was chronic with a median survival of 8 months, regardless of modalities of treatment. Two patients went through a period when the number of circulating leukemic cells was low ( ≦ 5%) before overt leukemia appeared. Other clinical features, signs, symptoms, routine laboratory data, serum anti‐ATL‐associated antibody, cell membrane markers and cytogenetic studies were similar to those observed in other districts of Kyushu island.