Prognostic factors and management of elderly sarcoma in Japan: the population-based National Cancer Registry (NCR) in Japan.

Abstract

Background: In aging societies like Japan, the number of elderly bone sarcoma (BS) and soft-tissue sarcoma (STS) patients is increasing. However, these malignancies' behavior is incompletely understood. We investigated clinical features, treatment modalities, survival, and prognostic factors for elderly BS and STS patients using Japan's National Cancer Registry (NCR).

Methods: We identified data for 11,015 individuals ≥ 70 diagnosed with BS or STS in 2016-2019 by ICD-O-3 cancer topography and morphology codes and analyzed patient characteristics, disease information, initial diagnostic process, treatment, and prognosis.

Results: We analyzed 1072 BS cases and 9933 STS cases. There was no significant sex difference among BS or STS. The most common histological subtypes were chondrosarcoma (N = 310, 29%) and liposarcoma (N = 1533, 15%). Twelve percent of BS and 11% of STS patients had distant metastasis at first presentation. Forty-six percent of BS and 50% of STS patients underwent surgery. The number of patients > 80 who underwent surgery or had chemotherapy was significantly smaller than patients 70-79 (P < 0.001; P < 0.001). Three-year overall survival (OAS) was 46% among BS and 50% among STS patients. Adjusted analyses provided significant associations between OAS and age, histological subtype, treatment, and extent of disease in BS, and age, sex, histological subtype, tumor location, treatment, and extent of disease in STS.

Conclusions: This study featured elderly BS and STS patients, presenting epidemiology, clinical characteristics, treatment, and oncological outcomes based on the NCR. It gives clinicians valuable information to develop treatments for elderly BS and STS patients for future aging societies.