Determination of placental ferritin (PLF)‐positive lymphocytes in women in early stages of breast cancer

Previous studies have proved that a certain acidic isoform of ferritin is specifically synthesized by the placenta and breast‐cancer tissue. In this context it has been further reported that the determination of this so‐called placental isoferritin (PLF) on the surface of a subset of peripheral lymphocytes is highly specific and sensitive for early stage breast cancer. By use of the monoclonal antibody CM‐H‐9 and flow cytometry, the levels of placental ferritin (PLF)‐positive cells were determined in 133 female patients undergoing surgical excision of a controversial or highly suspicious lesion of the breast detected by mammography. In addition, 61 healthy blood donors served as controls. Values of PLF‐positive cells in breast cancer patients differed significantly from those found in women with benign diseases and healthy controls (3.87% vs. 1.55% and 2.02, respectively; p < 0.00001). Analysis of prognostic factors in breast cancer patients (tumor size, lymph‐node status, menopausal status, estrogen receptor status, histologic grading and grading subfactors) revealed significantly higher levels of PLF‐positive cells in lymph‐node‐negative patients compared with node‐positive patients (p < 0.00001). Furthermore, levels of PLF‐positive cells s lowed a significantly negative correlation with tumor size and nuclear polymorphism. In 15 patients who underwent a guidewire‐directed surgical biopsy for a non‐palpable, mammographically suspect lesion, 4 cases of cancer correlated with high values of PLF‐positive lymphocytes while only I patient with a enign histologic result exhibited more than 4% positive cells. © 1992 Wiley‐Liss, Inc.