Prostaglandin F2 alpha in benign and malignant breast tumours

Prostaglandin F2 alpha (PGF2 alpha) was determined by radioimmunoassay in 57 breast carcinomata, 16 fibroadenomata, and 33 sclero-cystic-disease (SCD) specimens. In 41 cases of carcinoma and 10 cases of fibroadenoma, histologically non-malignant tissue was also obtained from the same breast. PGF2 alpha levels were significantly elevated in breast cancer when compared with the normal tissues and benign diseases (P less than 0.005 for each group). High PGF2 alpha levels were positively correlated with differentiation, positive oestrogen and progestagen receptor status, and low mitotic index. Tumours with good prognosis (less than 20 mm, negative lymph nodes, some degree of differentiation) showed significantly higher PGF2 alpha levels than tumours with a bad prognosis (greater than 20 mm, positive nodes and undifferentiated). A tendency for elevated PGF2 alpha levels was observed with negative lymphatic permeation, postmenopausal status, low grade of nuclear and cellular polymorphism and high degree of elastosis and fibrosis. No correlation was observed between PGF2 alpha levels and host-cell reaction. Plasma levels of 15-keto-13, 14-dihydro-PGF2 alpha were not elevated in cancer patients when compared with the SCD-group. The present study demonstrates that PGF2 alpha levels are high in tumours with good prognosis. However, since other authors have suggested that a high PGE2 production is a bad prognostic index, it is possible that conversion of PGE2 to PGF2 alpha by 9-keto-reductase explains this relationship. Nevertheless, the presented results question the unrestricted use of prostaglandin-synthesis-inhibitors in the treatment of breast cancer.