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Background and objectives: Prolactin is a lactogenic protein hormone secreted by the anterior pituitary that initiates and maintains lactation in mammals. Previous research has linked increased serum prolactin levels to breast cancer. However, there is a paucity of studies in the Indian population on the subject. The present study evaluated and compared serum prolactin levels in patients with breast cancer and patients with benign breast diseases.
Methods: This cross-sectional, comparative study was carried out at the Government Medical College, Nagpur (India) on patients with breast diseases in the out-patient department/in-patient department from June 2018 to November 2020. Breast cancer patients were considered cases, and those with benign breast diseases were considered controls. Breast carcinoma diagnosis was based on clinical features, fine needle aspiration cytology, and tissue histopathology in operated specimens for each patient. Fasting serum prolactin levels were measured by the chemiluminescence immunoassay method using the Advia Centaur immunoassay system.
Results: There were 120 female patients with breast diseases, of whom 60 had breast malignancy, and 60 had benign breast diseases. The mean age of patients with benign breast disease and breast cancer was 33.17 (1.75) and 49.77 (1.16) years, respectively (P<0.0005). Increased serum prolactin levels were observed in 93.3% of patients with breast cancer and 13.3% of patients with benign breast diseases. The mean serum prolactin level was significantly higher among breast cancer patients (102.68±7.03) ng/ml compared with patients with benign breast disease (16.31±1.72 ng/ml). We successfully determined a new cut-off value of serum prolactin level (>40.2 ng/ml) to differentiate breast cancer from benign breast diseases using the receiver operating characteristic curve analysis.
Conclusion: Patients with breast cancer have increased serum prolactin levels compared to patients with benign breast diseases. Thus, serum prolactin level can be used as a diagnostic marker for breast cancer. This is particularly beneficial to clinicians for differentiating breast cancer from benign breast diseases.