Abstract 4097: Clinicopathologic descriptors of subcutaneous panniculitis-like T-cell lymphoma (SPTCL): Analysis of a pooled database of a rare entity

Abstract

Abstract Introduction: SPTCL is a rare primary cutaneous T-cell lymphoma. SPTCL was initially described as an aggressive cutaneous T-cell lymphoma frequently associated with hemophagocytic syndrome (HPS) and requiring aggressive multiagent chemotherapy. In 2005, this entity was restricted to SPTCL with αβ phenotype, a less aggressive entity compared to its γδ counterpart, currently known as primary cutaneous γδ T-cell lymphoma. We conducted this analysis to explore the clinicopathologic characteristics of this little-known primary cutaneous T-cell entity. Methods: In order to study the demographic characteristics, molecular and immunohistochemical signatures, therapeutic interventions, survival, and prognostic factors, we compiled a pooled database of 214 cases. Descriptive statistics were calculated. Cox proportional-hazards model and Log-rank tests were used to assess the influence of demographic and clinicopathologic factors on overall survival (OS). Results: A total of 214 patients with confirmed SPTCL diagnosis were identified. The median age was 34 years with a peak incidence between ages 13 and 26. There was a female predominance with F:M ratio of 1.7. Upon presentation, 12% had lymphadenopathy, 12% had hepatosplenomegaly, and 27% had bone marrow involvement. No extra-nodal or extra-cutaneous involvement were reported. Cases expressed CD2 (8%), CD3 (85%), CD4(10%), CD5(10%), CD7 (9%), CD8 (77%), CD56 (6%), Granzyme-B (33%), and TIA-1 (34%). None of the cases expressed CD30. The most common clinical presentations were nodular skin changes (87%) followed by constitutional symptoms (57%). Fifteen and ten percent of SPTCL patients had history of immune-deregulatory disorders and immunosuppressive therapies, respectively. HPS occurred in 24% of the cases. Karyorrhexis, fat necrosis, and dermal involvement were noted in 15%, 9%, and 17%. The median duration of symptoms prior to diagnosis was 4 months. Median OS of the whole group was not reached while the mean OS was 73 months. OS was not impacted by sex, constitutional symptoms, immunocompromising factors, presence of lymphadenopathy, hepatosplenomegaly, or bone marrow involvement. OS was not impacted by histological or immunohistochemical features either. While older age and the occurrence of HPS negatively impacted OS, attaining complete remission positively impacted OS. Conclusions: This study presents a comprehensive clinicopathologic data from a pooled cohort of patients with SPTCL. It describes the clinicopathologic features of SPTCL and identifies major determinants of OS in this rare disease. Citation Format: Philip A. Haddad, Nowell Ganey. Clinicopathologic descriptors of subcutaneous panniculitis-like T-cell lymphoma (SPTCL): Analysis of a pooled database of a rare entity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4097.