PS1077 EVENT FREE SURVIVAL AT 12 MONTHS AND 24 MONTHS AS PREDICTORS FOR OUTCOME OF SYSTEMIC PERIPHERAL T CELL LYMPHOMA: ANALYSIS OF NATIONWIDE THAI LYMPHOMA STUDY GROUP

• Published in: HemaSphere Vol. 3; no. S1; pp. 488 - n/a
• Main Authors: Wudhikarn, K., Bunworasate, U., Julamanee, J., Lekhakula, A., Ekwattanakit, S., Khuhapinant, A., Norasetthada, L., Nawarawong, W., Laoruangroj, C., Numbenjapon, T., Niparuck, P., Chancharunee, S., Kanitsap, N., Wongkhatee, S., Makruasi, N., Wong, P., Sirijerachai, C., Chansung, K., Suwanban, T., Praditsuktavorn, P., Intragumtornchai, T.
• Format: Journal Article
• Language: English
• Published: 01-06-2019
• ISSN: 2572-9241; 2572-9241
• DOI: 10.1097/01.HS9.0000562600.01604.ae

Background:
Peripheral T cell lymphoma (PTCL) is relatively uncommon compared to B cell lymphoma (B‐NHL), however, it generally carries worse prognosis. Treatment failure and early relapse are major dilemma of PTCLs. Identification of high‐risk patients using various tools may better refine long‐term prognosis of PTCL patients. There were data indicating event free survival (EFS) at 12 months (EFS12) and 24 months (EFS24) as strong surrogate predictors for disease‐related outcomes in many B‐NHL. However, the implication of such surrogate end‐points has been limited in PTCLs. Herein, we explored EFS12 and EFS24 as tools to stratify survival outcome in PTCL patients.
Aims:
To EFS12 or EFS24 as a tool to stratify survival outcome in PTCL.
Methods:
Thai Lymphoma Study Group is the nationwide collaborative effort composing of 13 major medical centers in Thailand. The registry prospectively enrolled newly diagnosed lymphoma patients between 2006 and 2014. Here, we focused on systemic PTCL treated with chemotherapy and had adequate follow‐up data. EFS was defined as time between primary treatment to relapse, re‐treatment, or death from any causes. EFS12 and EFS24 were binary endpoints defined as whether developing events at 12 and 24 months after treatment initiation. Overall survival (OS) was defined as time from a specific timepoints either diagnosis or EFS12 to death. Logistic regression model was used to evaluate associations between clinical characteristics and EFS12/EFS24. Cox regression with EFS12/EFS24 as a time‐dependent covariate was applied to evaluate the association between EFS12 and OS.
Results:
There were 353 systemic PTCL in our cohort. A total of 292 (83%) patients received multiagent chemotherapy. Median age at diagnosis was 49 years (IQR 36–60 years). Median EFS and OS of patients who received treatment were 16.3 and 27.7 months (CI 95% 12.6–28.3 and 18.8–50.4 months respectively). A total of 138 patients (47.1%) developed an event within 12 months after treatment initiation (failed to achieve EFS12). Patients who failed to achieve EFS12 had higher proportion of impaired performance status, high IPI, and presence of B symptoms (Figure 1). After a median follow‐up of 53.7 months, Patients who achieved EFS12 had superior OS compared to patients who failed to achieve EFS12 (5‐years OS after treatment initiation 70.5% vs 12%, HR 7.03, 95%CI 5.07–9.74, p < 0.001). Landmark analysis confirmed the association between EFS12 and OS after 12 months timepoint (5‐years OS after EFS12 67.5% vs 11.5%, HR 6.45, 95%CI 4.65–8.96, p < 0.001). Similar results were seen with patients who achieved EFS24 for both survival after treatment initiation and after 24 months timepoint (Figure 1).
Summary/Conclusion:
EFS12 and EFS24 are strong surrogate endpoints for treatment outcomes in PTCL patients.