-Author name in bold denotes the presenting author
-Asterisk * with author name denotes a Non-ASH member
Clinically Relevant Abstract denotes an abstract that is clinically relevant.

PhD Trainee denotes that this is a recommended PHD Trainee Session.

Ticketed Session denotes that this is a ticketed session.

4185 Clinical Characteristics and Prognostic Analysis of Testicular Relapse in Pediatric Acute Lymphoblastic Leukemia: A Retrospective Multicenter Study from ChinaClinically Relevant Abstract

Program: Oral and Poster Abstracts
Session: 612. Acute Lymphoblastic Leukemias: Clinical and Epidemiological: Poster III
Hematology Disease Topics & Pathways:
Research, Lymphoid Leukemias, ALL, Clinical Research, Pediatric, Diseases, Lymphoid Malignancies, Study Population, Human
Monday, December 9, 2024, 6:00 PM-8:00 PM

Ning Wang1*, Shuhong Shen2, Xiuli Ju3*, Shaoyan Hu4*, Ju Gao5*, Yongjun Fang6*, Runming Jin7*, Ningling Wang, MD8*, Lirong Sun9*, Xiaowen Zhai, MD PhD10*, Lanlan Tang11*, Chunhui Yang, MS12*, Aiguo Liu13*, Yao Zou14*, Fang Liu, MD15*, Wenyu Yang, MD15*, Xiaojuan Chen, MD1* and Xiaofan Zhu, MD15

1Department of Pediatric Hematology and Oncology, State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences&Peking Union Medical College, Tianjin, China
2Department of Hematology , Shanghai Children’s Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
3Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
4Children's Hospital of Soochow University, Suzhou, China
5Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
6Department of Hematology and Oncology, Nanjing Children’s Hospital Affiliated to Nanjing Medical University, Nanjing, China
7Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wu Han, China
8Department of Hematology and Oncology, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
9Department of Pediatrics Hematology, The Affiliated Hospital of Qingdao University, Qingdao, China
10Department of Hematology and Oncology, Children's Hospital of Fudan University, Shanghai, China
11Department of Pediatrics, Xiangya Hospital Central South University, Changsha, China
12Kunming Children's Hospital, Kunming, AL, China
13Department of Oncology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
14State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin, China
15Department of Pediatric Hematology and Oncology, State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology& Blood Diseases Hospital, Chinese Academy of Medical Sciences& Peking Union Medical College, Tianjin, China

Background: The incidence of testicular relapse in pediatric acute lymphoblastic leukemia (ALL) has been reduced to 2% or lower with the application of modern intensive chemotherapy. However, testes remain the second most common sites for relapsed ALL in children and the management of testicular relapse has not been fully depicted. Herein, we performed a multicenter retrospective study to analyze the clinical features and outcome of pediatric ALL with testicular relapse. Methods: Sixty-seven childhood testicular relapsed ALL patients were enrolled in this study from 13 centers in China. They were all initial treated with the CCCG-ALL-2015 protocol between January 2015 and December 2019. The clinical features, treatment regimens and outcomes of patients were collected. The overall survival (OS) was estimated by the Kaplan‑Meier methods and the differences between groups were compared by the log-rank test. Cox proportional‑hazards regression model was used for multivariate analysis to evaluate the influencing factors of OS. Results: The median age was 7 years old. The median time from initial diagnosis to testicular relapse was 37 months. Sixty-six patients (99%) were B-ALL. Forty-one patients (61%) were diagnosed as isolated testicular relapse and the remaining 26 patients (39%) were testis combined with bone marrow and/or central nervous system relapse. Eight of 67 patients were abandoned treatment. Fifty-nine patients (88%) accepted treatment with subsequent evaluation. The median follow-up was 33 months and the 4-year OS was 80.1%. Treatment were heterogenous, including chemotherapy alone, irradiation, orchiectomy, CD19-chimeric antigen receptor T (CAR‑T) cell therapy and hematopoietic stem cell transplantation (HSCT). The 4-year OS of patients treated with CAR-T cell therapy, orchiectomy and chemotherapy alone were 93.8%, 90.0% and 38.1% (P<0.05), respectively. The 4-year OS of patients accepted HSCT was 77.1%. The 4-year OS of patients with isolated testicular relapse and combined relapse were 87.9% and 68.4% (P=0.064), respectively. Among thirty-seven isolated testicular relapsed children, 19 patients (51%) accepted CD19-CART cell therapy and 10 patients (27%) accepted orchiectomy. The 4-year OS were 92.9% and 100% (P>0.05), respectively. Multivariate analysis identified combined relapse (HR=5.901, 95%CI 1.237-28.158) and chemotherapy alone (HR=6.322, 95%CI 1.393-28.702) were independent prognostic factors for 4‑year OS (all P<0.05). Conclusion: Testicular relapse of pediatric ALL mainly occurred 3 years after initial diagnosis. Patients with isolated testicular relapse had a favorable outcome. For isolated testicular relapse, CART cell therapy and orchiectomy were both effective. Orchiectomy would affect fertility, while CART cell therapy is safe and effective and has an advantage in improving life-quality of survivors. For the testicular relapsed patients, chemotherapy alone was less effective, CAR-T cell therapy and/or HSCT are suggested.

Disclosures: No relevant conflicts of interest to declare.

*signifies non-member of ASH