Reduced-dose WBRT combined with SRS for 1–4 brain metastases aiming at minimizing neurocognitive function deterioration without compromising brain tumor control. (November 2022)

• Record Type: Journal Article
• Authors: Nakano, Toshimichi; Aoyama, Hidefumi; Onodera, Shunsuke; Igaki, Hiroshi; Matsumoto, Yasuo; Kanemoto, Ayae; Shimamoto, Shigetoshi; Matsuo, Masayuki; Tanaka, Hidekazu; Oya, Natsuo; Matsuyama, Tomohiko; Ohta, Atsushi; Maruyama, Katsuya; Tanaka, Takahiro; Kitamura, Nobutaka; Akazawa, Kohei; Maebayashi, Katsuya
• Is Part Of: Clinical and translational radiation oncology. Volume 37(2022)
• Page Start: 116
• Page End: 129
• Publication Date: 2022-11
• Subjects: Brain metastases -- Cognition -- Recurrence -- Radiation -- Whole brain -- Stereotactic radiosurgery; Cancer -- Radiotherapy -- Periodicals; Oncology -- Periodicals; Cancer -- Radiotherapy; Oncology; Radiation Oncology; Neoplasms -- radiotherapy; Translational Medical Research; Periodicals; Electronic journals; Periodicals; 616.9940642
• DOI: 10.1016/j.ctro.2022.09.005
• Languages: English
• ISSNs: 2405-6308

Abstract

Highlights: The addition of whole-brain radiotherapy (WBRT) to stereotactic radiosurgery (SRS) reduces the risk of brain tumor recurrence but standard-dose WBRT (SD-WBRT) accompanies the risk of neurocognitive decline. Reduced-dose WBRT (RD-WBRT) combined with SRS provides intracranial tumor control rate comparable to that after SD-WBRT + SRS. RD-WBRT could reduce the risk of neurocognitive decline compared to that after SD-WBRT. Abstract: Background and purpose: To minimize cognitive decline without increasing brain tumor recurrence (BTR) by reduced-dose whole-brain radiotherapy (RD-WBRT) (25 Gy, 10 fractions) + stereotactic radiosurgery (SRS) in patients with ≤ 4 brain metastases. Materials and methods: Eligible patients with ≤ 4 brain metastases on contrast-enhanced MRI and Karnofsky Performance Status ≥ 70. The primary endpoint was the non-inferiority of BTR at distant sites in the brain (BTR-distant)-free survival at 6 months compared to that of the standard dose (SD)-WBRT (30 Gy, 10 fractions) + SRS arm in a randomized clinical trial (JROSG99-1) of SRS with/without SD-WBRT. Secondary endpoints included BTR at any brain sites (BTR-all) and neurocognitive function assessed by a six-test standardized battery. Results: Forty patients from seven institutions were enrolled (median age 69 years). The primary tumor site was a lung in 28 patients; 20 patients had a solitary brain metastasis. The median survival time was 19.0 months (95 %CI: 13.8 %–27.5 %). The BTR-distant-free survival at 6 months was 76.9 % (59.5 %–87.7 %), which is comparable to that of historical control although predetermined non-inferiority (>71 %) could not be confirmed (p = 0.16). The cumulative incidence of BTR-all at 6 months accounting for the competing risk of death was 23.0 % (11.4–37.1), which was not worse than that of historical control (p = 0.774). The frequency of the cumulative incidence of persistent cognitive decline at 6 months was 48.6 % under the [>2.0 SD in ≥ 1 test] definition. Conclusions: RD-WBRT may yield comparable intracranial tumor control when combined with SRS, and may reduce the risk of neurocognitive decline compared to that after SD-WBRT.