Peripheral T-cell lymphoma-not otherwise specified, angioimmunoblastic T-cell lymphoma and anaplastic large cell lymphoma: Are the outcomes any different in Hispanics?

Abstract

e18773 Background: Peripheral T cell lymphoma – not otherwise specified (PTCL-NOS), angioimmunoblastic T-cell lymphoma (AITL) and anaplastic large cell lymphoma (ALCL) are unusual non-Hodgkin lymphomas with miscellaneous clinical characteristics which share the same treatment regimen (Blood PMID28115372 Cancer Treat ResPMID30596215 Blood PMID28115369). Gene expression profiling has facilitated their diagnosis; but much remains to be learned about risk factors, biological and clinical implications (Oncologist PMID16880242). This is the first national population-based analysis evaluating ethnic differences for Hispanics (HI) diagnosed with PTCL-NOS, AITL and ALCLin the US. Methods: Data were analyzed on PTCL-NOS, AITL and ALCL patients in the US reported to the Surveillance, Epidemiology, and End Results (SEER) database between 2000-2018. Demographic, clinical and survival patterns were analyzed. Kaplan-Meier and Cox regression analyses were used when appropriate. Multivariate analysis and propensity score matching were performed with adjustment for age, stage and B-symptoms. Results: 12,749 patients were diagnosed with PTCL-NOS, AITL and ALCL (1,666 cases were HI = 798 PTCL-NOS, 316 AITL and 552 ALCL). Male predominated for HI and Non-HI (NH) in the 3 malignancies. HI were diagnosed at a younger median age than NH, PTCL-NOS 60 years(y) vs 65y, AITL 65y vs 69y, and ALCL 45y vs 55y, respectively [p <0.001]. White race predominated for both. When diagnosed with PTCL-NOS or AITL, HI were more likely diagnosed from 2015-2018 but those with ALCL were identified from 2000-2004. For the 3 malignancies limited information regarding B symptoms was available. Most of the cases of HI and NH were diagnosed at advanced stages in all subtypes. Overall, for both the tendency was towards not receiving radiation. HI vs NH diagnosed with PTLC-NOS had median survival of 1.2 vs 1.3y; AITL was 2.2 vs 1.7y and ALCL 6.0 vs 9.3y. Survival probability for 2, 5 and 10y were comparable among HI and NH for all malignancies and no difference in OS was noted. On multivariate analysis, patients who were older than 80y and between 60-80 y, had worse OS compared to those <60y. For all subtypes, those who were diagnosed at stage III/IV had worse OS than those at early stage I/II. Conclusions: Similar OS for HI and NH diagnosed with PTCL-NOS, AITL and ALCL. Nonetheless, diagnosis at younger age and early stage play a significant role to better survival. Although HI were more subjected to early age at diagnosis and less likely to be at a stage I/II, no impact in survival was evidenced, which suggests that unique responses may counteract within this race. It is captivating that no gradual increase in diagnosis was noted despite the continuous development of genetic testing and improved diagnostic tools, which highlights that socioeconomical variables may have been influencing its access.