Clinical characteristics and prognostic analysis of 52 cases of ALK-positive anaplastic large cell lymphoma

Abstract

Abstract Objective: ALK-positive anaplastic large cell lymphoma (ALK+ ALCL) is a rare T-cell lymphoma. Anthracycline-based combination chemotherapy is the first-line treatment with a high remission rate, but the necessity of hematopoietic stem cell transplantation (HSCT) for consolidation remains inconclusive. This study aims to summarize the clinical characteristics of ALK+ ALCL and explore prognostic factors and treatment efficacy. Methods: A retrospective analysis was conducted on 52 ALK+ ALCL patients treated at the Institute of Hematology, Chinese Academy of Medical Sciences from May 2011 to November 2024. All patients had completed at least one line of chemotherapy with or without HSCT. Clinical characteristics, treatment outcomes, and prognostic factors were analyzed. Results: The median age of onset was 25.5 years (range: 11-64), with a male-to-female ratio of 2.3:1. At initial diagnosis, 81.1% (42/52) of patients were in advanced stages (III-IV), 55.8% (29/52) presented with B symptoms, and 28.8% (15/52) had elevated LDH levels. Extranodal involvement was observed in 59.6% (31/52) of patients, with 40.4% (21/52) having ≥2 extranodal sites involved. The International Prognostic Index (IPI) score was intermediate-high/high (3-5) in 21.2% (11/52) of patients. The median number of first-line treatment cycles was 6 (range: 2-8). First-line regimens included EPOCH (44.2%, 23/52), EPOCH (25%, 13/52), BV+CHP (21.2%, 11/52), and CHOP (9.6%, 5/52). With a median follow-up of 45.7 months, the complete remission (CR) rate for first-line treatment was 75% (39/52), and the overall response rate (ORR) was 90.4% (47/52). The 5-year overall survival (OS) rate was 91%, and the 5-year progression-free survival (PFS) rate was 67%. Primary refractory disease (n=5) and early relapse within 3 months of CR (n=6) were identified as significant prognostic factors for OS (P=0.039). Among these 11 patients, one who did not undergo transplantation had an OS of only 9.3 months, while the remaining 10 patients who achieved CR/PR with subsequent treatments and underwent HSCT had 8 survivors and 2 deaths due to relapse. In the chemotherapy-only group (n=30), IPI scores of 3-5 were significant prognostic factors for both OS and PFS (P=0.016; P=0.011). Among the 11 patients with IPI scores of 3-5, 4 received chemotherapy only (1 death, 1 sustained CR, 1 sustained PR, 1 lost to follow-up after progression), while 7 underwent chemotherapy followed by HSCT (6 survivors, 1 lost to follow-up within one year post-transplantation). The sustained CR rates for intermediate-high/high-risk patients treated with chemotherapy alone versus chemotherapy plus HSCT were 25% and 71.43%, respectively (P=0.24), with 5-year OS rates of 75% and 100% (P=0.19). CR rates for first-line regimens were 72.6% for EPOCH/EPOCH, 81.2% for BV+CHP, and 100% for CHOP. The corresponding ORRs were 88.8%, 90.9%, and 100%. The 5-year OS rates were 89%, 100%, and 100% (P=0.6).It was noting that the 5-year PFS rates were 74%, 40%, and 30% ( P=0.03). Conclusion: ALK+ ALCL predominantly affects males under 30 years of age, with most patients presenting at advanced stages. Pathological features include CD30 and EMA positivity. The disease shows high chemosensitivity, with EPOCH/EPOCH regimens demonstrating superior remission maintenance compared to other regimens. Overall survival is favorable, but primary refractory disease/early relapse within 3 months, and IPI scores ≥3-5 are poor prognostic factors. These patients may benefit from sequential HSCT following chemotherapy.