Delayed Cutaneous Hypersensitivity Reactions to Extracts of Breast Cancer and Melanoma Tissue in Cancer Patients<xref ref-type="fn" rid="FN2">2</xref>

Crude soluble extracts from breast cancer and malignant melanoma surgical specimens were obtained by the 3 m KCl method and assayed in cancer patients for a delayed cutaneous hypersensitivity reaction. The breast cancer extract was derived from a pool of 9 primary cancer specimens, whereas 8 melanoma extracts were prepared from single tumors; as controls, normal mammary and muscle tissues were employed. Positive response to the breast cancer extract was observed in 18 of 26 (69%) breast cancer patients and in 2 of 12 (17%) patients with other types of neoplasms. Reactivity to the individual melanoma extracts was varied: Positive reactions were observed in no patients with 1 extract, in 20–33% of the patients with 3 extracts, and in 75–93% with 4 extracts. By pooling the results obtained with the 8 melanoma extracts, we observed reactivity in 22 of 39 (56%) melanoma patients and in 12 of 23 (52%) patients with other tumors. Of 26 breast cancer patients, 5 (19%) reacted to normal mammary extract, and 5 of 28 (18%) melanoma patients reacted to muscle extracts; 20% and 25% of the patients with other types of tumors reacted to these extracts, respectively. The overall incidence of positive reactions to control extracts was 18 of 85 tests (21%). Ten of the 26 patients with breast cancer and 7 of the 39 patients with melanoma received simultaneous injections of extracts from breast cancer and melanoma. Most breast cancer patients reacted both to the breast cancer extract (70%) and to the melanoma extracts (90%), whereas all the melanoma patients reacted to the melanoma extracts and 2 (28%) reacted to the breast cancer extract. No correlation was found between positive response and clinical parameters, e.g., histologic diagnosis, stage of disease, age, sex, blood group, history of pregnancy, and time of surgery.