Objective: To investigate a possible association between mastitis and breast cancer risk in a cohort of Greek women. Material and methods:A series of 343 women who visited two breast clinics in Greece and delivered live neonates were studied in our case-control retrospective study. The case group comprised women with breast cancer and the control group women without breast cancer. All participants were subjected to a clinical examination with breast ultrasound and those aged over 40 years underwent digital bilateral mammography. Results:The χ2 (chi-square) test was the statistical tool used by us. We noted a statistically significant relationship between mastitis and risk for breast cancer (p=0.04). Moreover, the relative risk for breast cancer among patients with mastitis was RR: 2.069. Conclusion:Our study showed a relation between mastitis and breast cancer. Mastitis could be a potential risk factor. Further studies with larger number of patients are mandatory in order to confirm this possible relationship.