Pregnancy-associated breast cancer: gestational weight gain impact and nomogram validation

As a rare form of breast cancer, the prognosis and influencing factors of pregnancy-associated breast cancer (PABC) remain insufficiently understood. This study aimed to explore the prognostic factors affecting PABC patients, and establish a nomogram for predicting prognosis.

Patients with PABC and non-PABC, who were treated at three large tertiary institutions, were included in the analysis. The demographic and tumor characteristics of the patients were collected, and their survival were followed up. A Cox proportional hazard regression model was performed to analyze the effects of different variables on the risk of disease-free survival (DFS) in PABC patients. A prognostic nomogram was developed to predict DFS, and its performance was validated using the concordance index, calibration curves, ROC analysis, and decision curve analysis.

Sixty-nine PABC patients and matched non-PABC patients were included in the study. Compared to non-PABC group, PABC patients have less favorable fertility conditions and outcomes, poorer clinicopathological characteristics and worse prognosis. In the analysis of prognostic factors of PABC patients, gestational weight gain (GWG) was identified as an independent factor affecting DFS in PABC patients. A nomogram was subsequent established to predict the possibility of DFS in patients with PABC, and multiple analyses confirmed the robust predictive ability and clinical value of the model.

PABC patients exhibited poorer prognosis compared to non-PABC patients, with GWG identified as a pregnancy-related risk factor influencing their outcomes. The established nomogram showed robust predictive accuracy and holds promise for informing clinical decision-making.