To investigate the predictive value of red cell distribution width/albumin ratio (RAR), platelet/lymphocyte ratio (PLR), and ALDH1A2 gene methylation for the prognosis of female breast cancer patients.

The clinical data of 242 female breast cancer patients who underwent modified radical mastectomy from January 2020 to December 2024 were retrospectively collected. The patients were divided into a favorable prognosis group (n=179) and an unfavorable prognosis group (n=63) based on whether they experienced recurrence or distant metastasis after surgery. The methylation status of the ALDH1A2 gene in cancer tissues and adjacent normal tissues was detected by methylation-specific PCR (MSP), and the differences in RAR, PLR, and ALDH1A2 methylation between the two groups were compared. Kaplan-Meier survival curves, Logistic regression, and receiver operating characteristic curves were used to analyze the prognostic predictive value.

The positive rate of ALDH1A2 methylation in cancer tissues of 242 female breast cancer patients was 36.4% (88/242), which was higher than 10.3% (25/242) in adjacent normal tissues (χ²=45.822, P<0.001). The levels of RAR, PLR, and the positive rate of ALDH1A2 methylation in the unfavorable prognosis group were higher than those in the favorable prognosis group (all P<0.05). ALDH1A2 methylation was related to pTNM stage, histological grade, lymph node metastasis, and estrogen receptor (ER) status (all P<0.05). ALDH1A2 methylation positive patients had a lower cumulative disease-free survival rate than those with negative methylation (47.7% vs. 89.0%, Log-Rank χ²=57.063, P<0.001). Logistic regression analysis showed that histological grade Ⅱ~Ⅲ, lymph node metastasis, RAR≥0.5 %·L/g, PLR≥123.2, and positive ALDH1A2 methylation were independent risk factors for unfavorable events in female breast cancer patients (all P<0.05). The AUC of ALDH1A2 methylation, RAR, PLR, and their combination for predicting unfavorable prognosis in female breast cancer patients were 0.748, 0.801, 0.776, and 0.914, respectively, with the highest combined predictive efficacy (all P<0.05).

Positive ALDH1A2 gene methylation, elevated RAR, and elevated PLR are closely related to the unfavorable prognosis of female breast cancer patients. Combined detection of ALDH1A2 methylation, RAR elevation, and PLR elevation can improve the efficacy of prognostic risk assessment for female breast cancer patients.