Association of mean cardiac dose with model-predicted risk of radiation-induced pericarditis in breast cancer patients

Purpose This study aimed to investigate the association between mean cardiac dose (MCD) and the model-predicted risk of radiation-induced pericarditis in breast cancer patients undergoing radiotherapy. Methods A retrospective cohort study was conducted on 277 breast cancer patients treated with radiotherapy at the First Affiliated Hospital of Xi'an Jiaotong University between January 2022 and June 2023. Patients were categorized into three groups based on their MCD: the low MCD group (≤420 cGy), the medium MCD group (420–648 cGy), and the high MCD group (>648 cGy). Logistic regression models were used to analyze the relationship between MCD and pericarditis risk, adjusting for potential confounders. Results According to normal tissue complication probability (NTCP) modeling, patients in the high MCD group exhibited a significantly elevated model-predicted risk of developing pericarditis (OR = 6.66, 95 % CI: 1.32–33.56, P  = 0.046) compared to the low MCD group. The medium MCD group did not show a statistically significant increase in risk (OR = 0.71, 95 % CI: 0.29–1.01). Notably, the predicted risk increased markedly beyond a threshold MCD range. The association remained robust across various adjusted models, including those accounting for age, BMI, comorbidities, and other confounders. These findings highlight the critical role of MCD as a predictive factor for radiation-induced pericarditis, emphasizing the importance of meticulous dose management to mitigate this adverse outcome in breast cancer patients. Conclusion Higher mean cardiac doses are significantly associated with an increased risk of radiation-induced pericarditis in breast cancer patients. These findings underscore the importance of minimizing cardiac exposure during radiotherapy to reduce the risk of adverse cardiac events.