KEY TAKEAWAYS
- The study aimed to explore the effect of concurrent ADC and radiotherapy on SRN in patients with BM.
- The results revealed that Concurrent ADC and radiotherapy correlate with increased SRN risk in HER2+ breast cancer patients.
The complex interplay between brain cancer progression and treatment modalities like radiotherapy and ADC warrants thorough investigation.
Yutaro Koide and the team aimed to assess the effect of concurrent ADC and radiotherapy on symptomatic radiation necrosis (SRN) in breast cancer patients with brain metastases (BM).
The study utilized data from 4 institutions, eligibility criteria included histologically confirmed breast cancer, diagnosis of BM via gadolinium-enhanced MRI, Karnofsky performance status of 60 or higher, and radiotherapy for all BM lesions from 2017 to 2022. Patients with leptomeningeal dissemination were excluded. Concurrent ADC was defined as ADC use within 4 weeks before or after radiotherapy.
The study compared the cumulative incidence of SRN until December 2023, considering death as a competing event between groups with and without concurrent ADC. Multivariable analysis was conducted using the Fine-Gray model.
Among the 168 enrolled patients, 48 (29%) received ADC, with 19 (11%) having concurrent ADC. Of these, 36% were HER2-positive, 62% had symptomatic brain metastases, and 33% had previous brain metastases radiation histories. Over a median follow-up of 31 months, 18 SRNs (11%) were recorded, with 11 in grade 2 and 7 in grade 3.
The groups with and without concurrent ADC experienced 5 SRNs in 19 patients and 13 SRNs in 149, respectively. The 2-year cumulative SRN incidence was 27% vs. 7% (P = 0.014). Concurrent ADC correlated with a higher SRN risk on multivariable analysis (subdistribution HR, 3.0 [95% CI: 1.1–8.3], P = 0.030).
The study indicated that simultaneous use of ADC and radiotherapy is linked to an increased SRN risk in HER2-positive breast cancer patients.
Funding support was provided by the Japan Society for the Promotion of Science.
Source: https://link.springer.com/article/10.1007/s11060-024-04681-8
Koide, Y., Nagai, N., Adachi, S. et al.(2024) “Impact of concurrent antibody–drug conjugates and radiotherapy on symptomatic radiation necrosis in breast cancer patients with brain metastases: a multicenter retrospective study.” J Neurooncol (2024). https://doi.org/10.1007/s11060-024-04681-8
