Impact of concurrent antibody–drug conjugates and radiotherapy on symptomatic radiation necrosis in breast cancer patients with brain metastases: a multicenter retrospective study

• Published in: Journal of neuro-oncology Vol. 168; no. 3; pp. 415 - 423
• Main Authors: Koide, Yutaro, Nagai, Naoya, Adachi, Sou, Ito, Masayuki, Kawamura, Mariko, Ito, Makoto, Ito, Fumitaka, Shindo, Yurika, Aoyama, Takahiro, Shimizu, Hidetoshi, Hashimoto, Shingo, Tachibana, Hiroyuki, Kodaira, Takeshi
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.07.2024; Springer Nature B.V
• Subjects: Adult; Aged; Brain cancer; Brain Neoplasms - radiotherapy; Brain Neoplasms - secondary; Breast cancer; Breast Neoplasms - pathology; Breast Neoplasms - radiotherapy; Chemoradiotherapy - adverse effects; ErbB-2 protein; Female; Follow-Up Studies; Gadolinium; Humans; Immunoconjugates; Medicine; Medicine & Public Health; Meninges; Metastases; Metastasis; Middle Aged; Necrosis; Neurology; Oncology; Radiation Injuries - epidemiology; Radiation Injuries - etiology; Radiation Injuries - pathology; Radiation therapy; Retrospective Studies; Brain metastases; Trastuzumab emtansine; Antibody–drug conjugates; Radiotherapy; Trastuzumab deruxtecan; Radiation necrosis
• ISSN: 0167-594X; 1573-7373; 1573-7373
• DOI: 10.1007/s11060-024-04681-8

    Aim We aimed to investigate the impact of concurrent antibody–drug conjugates (ADC) and radiotherapy on symptomatic radiation necrosis (SRN) in breast cancer patients with brain metastases (BM). Methods This multicenter retrospective study uses four institutional data. Eligibility criteria were histologically proven breast cancer, diagnosed BM with gadolinium-enhanced MRI, a Karnofsky performance status of 60 or higher, and radiotherapy for all BM lesions between 2017 and 2022. Patients with leptomeningeal dissemination were excluded. Concurrent ADC was defined as using ADC within four weeks before or after radiotherapy. The cumulative incidence of SRN until December 2023 with death as a competing event was compared between the groups with and without concurrent ADC. Multivariable analysis was performed using the Fine-Gray model. Results Among the 168 patients enrolled, 48 (29%) received ADC, and 19 (11%) had concurrent ADC. Of all, 36% were HER2-positive, 62% had symptomatic BM, and 33% had previous BM radiation histories. In a median follow-up of 31 months, 18 SRNs (11%) were registered (11 in grade 2 and 7 in grade 3). The groups with and without concurrent ADC had 5 SRNs in 19 patients and 13 SRNs in 149, and the two-year cumulative incidence of SRN was 27% vs. 7% ( P  = 0.014). Concurrent ADC was associated with a higher risk of SRN on multivariable analysis (subdistribution hazard ratio, 3.0 [95% confidence interval: 1.1–8.3], P  = 0.030). Conclusions This study suggests that concurrent ADC and radiotherapy are associated with a higher risk of SRN in HER2-positive breast cancer patients.