Prophylactic cranial irradiation (PCI) in high-risk breast cancer patients: Preliminary data

Abstract

11501 Background: The rationale behind PCI is to control or eradicate undetectable micro-metastases without inducing severe adverse effects. In this study we assessed the effect of PCI in high-risk breast cancer patients. Methods: 62 consecutive patients, with high-risk breast cancer were enrolled in this trial and were randomized into 2 arms: Arm 1 included 31 patients who didn’t receive PCI. Arm 2 included 31 patients who received PCI. In arm 2, PCI was given after finishing the adjuvant treatment and before starting hormone therapy if indicated. The whole brain received 2.4 Gy per fraction, to a total dose of 24 Gy. MRI to the brain was part of the neurological assessment of the 62 patients included prior to adjuvant treatment, 6 months in the first year, and then annually. Neuro-cognitive Functions (NCF) were evaluated basically prior to and then 6 months and 1 year after PCI using Mini-Mental State Exam (MMSE). Functional Assessment of Cancer Therapy-Brain (FACT-Br) Questionnaire has been applied to assess health-related quality of life of the 62 patients included. Results: None of the patients in the PCI arm developed brain metastases in comparison to 6.4% in control arm. There is no statistical difference between control arm and PCI arm regarding the site of metastasis, P= 0.167. Alopecia was the most common side effect of PCI with G1 occurred in 48.4% of cases, and G2 occurred in 51.6% of cases and most of PCI arm cases showed hair re-growth within 11–15 weeks. PCI was well tolerated by most of patients. G1 and G2 headache occurred in 32.3% and 6.5% of patients, respectively. The initial levels of NCF in both arms were comparable, with no statistical difference through MMSE scores between both arms of the study, P=0.619. In PCI arm most of the MMSE scores were decreased at the 6 months assessment, but returned to the initial level at the one year assessment with no statistical difference among both groups. QOL was comparable in both groups prior to and at the end of treatment. The mean of DFS in control arm was 14.10 months (95% CI 10.18–18.02) and in PCI arm it was 18.42 months (95%CI 10.46–26–37), P=0.387. Conclusions: PCI was associated with tolerated toxicities and resulted in decreased incidence of CNS metastases. Whether this result may be translated into therapeutic gain warrants further evaluation. No significant financial relationships to disclose.