The use of oncofetal ferritin-bearing lymphocytes as a marker for the screening, diagnosis, and follow-up of patients with early breast malignancy screening of 3400 women.

The potential of using a blood test enumerating oncofetal ferritin-bearing lymphocytes (FBL) as a biomarker for early breast cancer was further explored. Nine hundred women attending a high-risk breast cancer clinic and 2500 normal-risk women were physically examined and their blood drawn for FBL determination using a newly developed radioimmunoassay. The FBL test results were compared to clinically or histopathologically diagnosed breast disease and to known breast cancer risk factors. A gradual increase in the mean FBL ratio was seen from normal risk disease-free women to those with in situ or early stage breast cancer. The percentage of women with positive FBL was 13.6% for the normal risk group, 19% and 25.7% for clinically and histopathologically diagnosed benign breast disease, respectively, and 100, 77.8, and 66.7% for in situ, Stage I, and Stage II breast cancer, respectively. In locally advanced disease (Stage III) the percentage of positive women was only 17.2%. It was further found that a negative FBL result in known breast cancer patients at Stage I, II of the disease was a bad prognostic marker indicating a shorter disease-free survival. The follow-up of patients after surgery by periodical clinical examination and the FBL test revealed that the positive FBL was declining after removal of the precancerous or malignant tumor and that it was highly sensitive (100%) in predicting tumor development and recurrence. Using a logistic regression analysis, an FBL-positive test indicated a significant association with risk of early breast cancer (odds ratio = 2.9; 95% confidence interval = 1.4-5.8). Being a measure of the immune response the positive FBL was associated with early breast cancer and good prognosis. Since patients with locally advanced cancer and poor prognosis were FBL negative but such patients were shown to have increased serum ferritin levels. It is suggested to use the FBL and serum ferritin assays for screening and diagnosis of breast cancer.