Background: In preclinical studies, müllerian inhibiting substance (MIS) has a protective affect against breast cancer. Our objective was to determine whether serum MIS concentrations were associated with cancerous or precancerous lesions. Blood from 30 premenopausal women was collected and serum extracted prior to their undergoing breast biopsy to assess a suspicious lesion found on imaging or physical examination. Based on biopsy results, the serum specimens were grouped as cancer (invasive or ductal carcinoma in situ), precancer (atypical hyperplasia or lobular carcinoma in situ), or benign.
Findings: Serum from women with cancer and precancer (p = .0009) had lower MIS levels than serum from women with benign disease.
Conclusion: Our findings provide preliminary evidence for MIS being associated with current breast cancer risk, which should be validated in a larger population.