Abstract 4916: Impact of primary organ site on prognosis in extranodal peripheral T cell lymphoma not otherwise specified
Authors: Al-Juhaishi Taha , Khurana Arushi , Shafer Danielle , Yazbeck Victor 
Published: August 2019

Abstract
Introduction: Peripheral T cell lymphoma, not otherwise specified (PTCL, NOS) is a rare heterogeneous group of diseases that constitutes 25% of T-cell lymphomas. It predominately affects men with a median age of 60 years at presentation. It is known to be an aggressive disease with high risk of relapse and subsequent poor response to systemic therapies. In this study, we sought to investigate the impact of primary site of disease on prognosis in extranodal PTCL, NOS.
Methods: The Surveillance, Epidemiology and End Results (SEER) database was used to identify adult patients (≥20 years) diagnosed with PTCL, NOS between 1973 and 2014. Primary sties excluded were lymph nodes, bone marrow, spleen and skin. All stages of disease were included; treatment effect (surgery, radiation, chemotherapy) was analyzed when available. Sites of disease were grouped into 5 organ systems for convenience. Overall survival (OS) was estimated using the Kaplan-Meier method, and compared using Log-Rank test. Cox proportional hazards models were used for adjusted survival analyses.
Results: Total of 392 patients were included. Median age was 62 years, and majority were male (n=242, 61.7%) Caucasian (n=224, 57.1%), and married (n=231, 58.9%). Gastrointestinal/hepatobiliary site was the most common primary extranodal organ system involved (n=156, 39.8%), followed by head and neck (n=147, 37.5%), thoracic excluding breast (n=42, 10.7%), CNS (n=32, 8.2%), and breasts (n=15, 3.8%). Most patients had stage IV disease (n=116, 29.6%). Total of 137 (34.9%) patients had surgery to the primary site, 94 (24%) had radiation, and 241 (61.5%) received chemotherapy. Median overall survival was 13 (0-252) months, and was statistically different by primary organ system involved (p&lt; 0.001). Gastrointestinal/hepatobiliary group had the worst median survival of only 8 months (95% CI 4.3- 11.6), followed by thoracic [median of 9 months; 95% CI (0.0 - 21.7)], and CNS [median of 12 months; 95% CI (3.5 - 20.4)]. Lymphoma was the most common cause of death (n=166, 42.3%). On univariate analysis, patients who received surgery did not have better survival [HR 0.909; 95% CI (0.70-1.16)]; while patients who received radiation [HR 0.53; 95% CI (0.39-0.71)], or chemotherapy [HR 0.76; 95% CI (0.60-0.98)] had better outcomes. In a multivariate analysis model; stage IV disease and Hispanic race were significantly associated with worse survival; while being married, undergoing radiation or chemotherapy was associated with better survival.
Conclusion: PTCL, NOS is a rare aggressive disease mostly affecting elderly men. Lymphoma involving gastrointestinal /hepatobiliary system is the most common site of primary extranodal disease and portends the worst survival. Patients who received radiation or chemotherapy had better outcomes.
Citation Format: Taha Al-Juhaishi, Arushi Khurana, Danielle Shafer, Victor Yazbeck. Impact of primary organ site on prognosis in extranodal peripheral T cell lymphoma not otherwise specified [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4916.