Repeated Stereotactic Radiotherapy for Local Brain Metastases Failure or Distant Brain Recurrent: A Retrospective Study of 184 Patients

Laure Kuntz; Clara Le Fèvre; Delphine Jarnet; Audrey Keller; Philippe Meyer; Christophe Mazzara; Hélène Cebula; Georges Noel; Delphine Antoni

doi:10.3390/cancers15204948

Repeated Stereotactic Radiotherapy for Local Brain Metastases Failure or Distant Brain Recurrent: A Retrospective Study of 184 Patients

Cancers (Basel). 2023 Oct 11;15(20):4948. doi: 10.3390/cancers15204948.

Authors

Laure Kuntz¹, Clara Le Fèvre¹, Delphine Jarnet², Audrey Keller¹, Philippe Meyer², Christophe Mazzara², Hélène Cebula³, Georges Noel¹, Delphine Antoni¹

Affiliations

¹ Department of Radiation Oncology, Institut de Cancérologie Strasbourg Europe (ICANS), UNICANCER, Paul Strauss Comprehensive Cancer Center, 17 Rue Albert Calmette, 67200 Strasbourg, France.
² Department of Medical Physics, Institut de Cancérologie Strasbourg Europe (ICANS), UNICANCER, Paul Strauss Comprehensive Cancer Center, 17 Rue Albert Calmette, 67200 Strasbourg, France.
³ Neurosurgery Department, Hôpitaux Universitaires de Strasbourg, 1, Avenue Molière, 67098 Strasbourg, France.

Abstract

Background: The main advantages of stereotactic radiotherapy (SRT) are to delay whole-brain radiotherapy (WBRT) and to deliver ablative doses. Despite this efficacy, the risk of distant brain metastases (BM) one year after SRT ranges from 26% to 77% and 20 to 40% of patients required salvage treatment. The role and consequences of reirradiation remain unclear, particularly in terms of survival. The objective was to study overall survival (OS) and neurological death-free survival (NDFS) and to specify the prognostic factors of long-term survival.

Methods: we retrospectively reviewed the data of patients treated between 2010 and 2020 with at least two courses of SRT without previous WBRT.

Results: In total, 184 patients were treated for 915 BMs with two-to-six SRT sessions. Additional SRT sessions were provided for local (5.6%) or distant (94.4%) BM recurrence. The median number of BMs treated per SRT was one with a median of four BMs in total. The mean time between the two SRT sessions was 8.9 months (95%CI 7.7-10.1) and there was no significant difference in the delay between the two sessions. The 6-, 12- and 24-month NDFS rates were 97%, 82% and 52%, respectively. The 6-, 12- and 24-month OS rates were 91%, 70% and 38%, respectively. OS was statistically related to the number of SRT sessions (HR = 0.48; p < 0.01), recursive partitioning analysis (HR = 1.84; p = 0.01), salvage WBRT (HR = 0.48; p = 0.01) and brain metastasis velocity (high: HR = 13.83; p < 0.01; intermediate: HR = 4.93; p < 0.01).

Conclusions: Lung cancer and melanoma were associated with a lower NDFS compared to breast cancer. A low KPS, a low number of SRT sessions, synchronous extracerebral metastases, synchronous BMs, extracerebral progression at SRT1, a high BMV grade, no WBRT and local recurrence were also associated with a lower NDFS. A high KPS at SRT1 and low BMV grade are prognostic factors for better OS, regardless of the number of BM recurrence events.

Keywords: brain metastases; oligorecurrence; radiotherapy; reirradiation; repeated radiosurgery; salvage radiation; stereotactic radiosurgery.

Grants and funding

This research received no external funding.