Progesterone binding cyst protein (PBCP) in primary breast cancer: a new prognostic factor?

Different secretory proteins have been evaluated as possible tumor markers in breast cancer. In this study progesterone binding cyst protein (PBCP) has been quantitated in breast tumor tissue. We report on a correlation of PBCP in cytosols of primary breast cancer, with known prognostic factors. A significant difference (p less than 0.001, Chi-square) in the frequency of PBCP-negative patients in clinical Stage I and Stage II is found. This was mainly attributed to a difference between T1 and T2 tumors, with less contribution from nodal status. A biological function of PBCP in breast cancer is not known. The distribution of PBCP in our patients has a close resemblance with expected number of node positive patients, suggesting that PBCP as a tumor marker may aid in providing prognostic information in breast cancer patients.