Increased Radiosensitivity of Solid Tumors Harboring ATM and BRCA1/2 Mutations

Area of Science:

• Oncology
• Genetics
• Radiotherapy Research

Background:

• Radiotherapy (RT) efficacy is influenced by tumor DNA damage repair mechanisms.
• Investigating the role of specific gene mutations in DNA repair pathways is crucial for predicting RT outcomes.

Purpose of the Study:

• To determine the impact of mutations in ATM and/or BRCA1/2 genes on treatment outcomes in solid tumor patients receiving RT.
• To correlate DNA damage repair gene mutations with response rates and local recurrence after radiotherapy.

Main Methods:

• Retrospective review of 97 solid tumor patients who underwent next-generation sequencing and received RT.
• Comparison of objective response rate and cumulative local recurrence rate (LRR) based on the presence or absence of mutations in ATM and/or BRCA1/2.
• Propensity score matching was used to create a control group of patients without these mutations.

Main Results:

• Patients with mutations in both ATM and BRCA1/2 (ATMmtBRCAmt) showed the highest objective response rate (80%) to RT.
• The ATMmtBRCAmt group exhibited the lowest 1-year cumulative local recurrence rate (0%) compared to wild-type (ATMwtBRCAwt) group (47.9%).
• No significant difference in RT-associated toxicities was observed among the patient subgroups.

Conclusions:

• Tumors harboring ATM and/or BRCA1/2 mutations demonstrate enhanced response and local control following radiotherapy.
• Tumor mutation profiling of DNA repair genes like ATM and BRCA1/2 may inform RT treatment planning.
• These findings are hypothesis-generating and warrant further investigation into personalized RT strategies.