Adult T-Cell Leukemia/Lymphoma: A Clinicopathologic Study of 126 Cases from the International T-Cell Lymphoma Project.

To assess the clinicopathological applicability and reproducibility of the new WHO classification against peripheral T/NK-cell lymphomas, International T-cell Lymphoma Study Group was organized. Our task is to show the clinicopathologic and therapeutic results of ATLL from International T-cell Lymphoma Project. In the study, 1159 cases of T/NK-cell lymphomas, excluding mycosis fungoides and Sezary syndrome, were collected from the 21 centers in 13 countries of North America, Europe and Asia. All cases were reviewed by expert hematopathologists.

ATLL was diagnosed in 126 (10.9%) patients. It was rare in North America (2.0%), and Europe (1.5%), but frequent in Asia (24.8%). There were clinical subtypes of ATLL from smoldering, chronic, lymphoma to acute type, and 87% of the patients fell into lymphoma type. The median age was 60 (range; 15–92) and male to female ratio was 1. B symptoms, PS 2–4(ECOG) and two or more extranodal sites were found in 39 (31%), 29 (23%) and 43 (34%) patients, respectively. Bone marrow involvement was present in 28% of the patients. Stage I/II was seen in 10% of the patients, stage III in 18% and stage IV in 73%. There were 23 (19%) patients in score 0/1, 41 (33%) in score 2, 40(32%) in score 3 and 20(16%) in score 4/5 of International Prognostic Index (IPI). There were 20 (17%) patients with less than 150x10³/ml of platelet counts, 107 (85%) with over 20% transformed T cells in absolute lymphocyte counts, and 113 (94%) with over 20% Ki-67 positive cells. The 5- year-overall survival (OS) and failure free survival (FFS) were 14.4% and 12.1%, respectively. The significant prognostic factors for OS were B symptoms (p=0.018), PS (p=0.0022), stage (p=0.019), extranodal sites (p=0.045) and IPI (p=0.019). By using the multivariate analysis, the important prognostic factors were found to be B symptoms, platelet counts (<150x10³/ml), transformed T-cell counts (>20%), and Ki67+ cells (>20%). However, the Cox model analysis showed that no significant prognostic factors were found after adjusting by IPI. For treatment, the combination chemotherapy using anthracycline as an initial therapy was given in 109 of 120 (91%) treated patients. The overall and complete response rates were 69% and 33%, respectively. It is unfortunate that 71 (63%) patients had relapsed. Many drugs were used including prednisone 105 (88%), vincristine 102 (85%), cyclophosphamide 92 (77%), doxorubicin 77 (64%), etoposide 53 (44%), mitoxantrone 14 (12%), cisplatin 11 (9%), methotrexate 8 (7%) , bleomycin 6 (5%) and cytarabine 5 (4%). There was no difference in OS and FFS according to the treatment arms includ.