Validation of the Usefulness of Satl-PI and JCOG-PI As Predictors of Prognosis at the Start of Second-Line Treatment

Background: The simplified ATL-prognostic index (sATL-PI) is a prognostic index at the diagnosis for patients with acute and lymphoma type adult T-cell leukemia-lymphoma (ATL). It is determined by 5 parameters including ECOG-PS, clinical stage, age, serum albumin level, and soluble IL-2 receptor level which makes possible to stratify patients into three groups with different survival. In addition, the Japan Clinical Oncology Group-prognostic index (JCOG-PI) is a prognostic index at the diagnosis for aggressive ATL (acute and lymphoma, unfavorable chronic type ATL). It is defined by corrected calcium levels and ECOG-PS which makes possible to stratify patients into two groups with different survival. So far, no prognostic index is available for patients receiving later lines of treatment. In this study, we evaluated the applicability of sATL-PI and JCOG-PI to predict the outcome at the time of initiating second line treatment upon relapse or refractory disease, and intolerance to first line treatment.

Patients and Methods: We retrospectively reviewed the medical records in patients with acute and lymphoma type ATL newly diagnosed from January 2009 and March 2021 in our department. The potential of sATL-PI and JCOG-PI at the initiation of second-line treatment to predict the subsequent survival was evaluated. This study was approved by institutional review board of Kagoshima University Hospital.

Results and Discussion: Among 130 patients with acute and lymphoma type ATL, 67 patients who were available the determinants for sATL-PI at the start of second-line treatment were analyzed. Median observation period of the 67 patients is 3.73 (0.79-9.28) year, 38 male/29 female, median age 65 (42-84) years-old, and median time from 1^st line treatment to 2^nd line treatment is 6.7 (0.6-94.0) months. At the time of initiation of second line treatment, 6, 34, and 27 patients were categorized in high, intermediate, and low risks by sATL-PI. The median survival from the first day of second line treatment 0.75 years, 4.91 years, and 8.33 years for high, intermediate, and low risks by sATL-PI, respectively (P=0.0000000279). For JCOG-PI, among 140 aggressive ATL patients, 73 patients who were available for JCOG-PI at the start of second-line treatment were analyzed. Median observation period of the 67 patients is 3.73 (0.79-9.28) year, 40 male/33 female, median age 64 (42-86) years-old, median time from 1^st line treatment to 2^nd line treatment is 6.0 (0.6-94.0) months. At the time of initiation of second line treatment, 22 and 51 patients were categorized and the median survival after that time in each group was 0.83 years and 1.68 years, in high and moderate risks by JCOG-PI, respectively (P=0.000289). Although the number of cases available for analysis was small, both prognostic indexes were also useful in predicting prognosis at the start of third-line treatment.

Conclusion: This study indicates that sATL-PI and JCOG-PI at the second-line treatment is useful for the prediction of subsequent survival. These indices will be a novel tool to perform clinical trials for relapsed/refractory ATL efficiently.

Nakamura:Sanofi: Honoraria; Takeda Pharmaceutical Company Limited: Honoraria; Nippon-Shinyaku: Honoraria; Chugai Pharmaceutical Co., Ltd.: Honoraria; Janssen: Honoraria; AbbVie: Honoraria; Meiji Seika: Honoraria. Tabuchi:AbbVie: Honoraria; Nippon-Shinyaku: Honoraria; Sanofi: Honoraria. Arima:Sanofi: Honoraria. Arai:Sanofi: Honoraria. Yoshimitsu:Sanofi: Honoraria; DAIICHI SANKYO COMPANY, LIMITED.: Honoraria; Otsuka Pharmaceutical: Honoraria; Novartis Japan: Honoraria; CSL Behring: Honoraria; Chugai Pharmaceutical Co., Ltd.: Honoraria; Takeda Pharmaceutical Company Limited: Honoraria. Ishitsuka:Astellas: Honoraria; Eisai: Honoraria; Meiji Seika: Consultancy, Honoraria; Nippon-Shinyaku: Honoraria; Otsuka: Honoraria; OQVIA: Honoraria; Janssen: Honoraria; Pfizer: Honoraria; Otsuka: Honoraria; Yakult: Honoraria; Sanofi: Honoraria; Ono: Honoraria, Research Funding; Daiichi Sankyo: Consultancy, Honoraria; Celgene: Honoraria; BMS: Honoraria; Chugai: Honoraria; Kyowa Kirin: Honoraria, Research Funding; Takeda: Honoraria; CSL Behring: Honoraria; AbbVie: Honoraria.