EXPRESSION OF A MELANOMA-TUMOR-ASSOCIATED ANTIGEN AS DEMONSTRATED BY A MONOCLONAL-ANTIBODY (D6-1) IN CYTOPATHOLOGIC PREPARATIONS OF HUMAN-TUMOR CELLS FROM EFFUSIONS AND NEEDLE ASPIRATES

  • 1 January 1985
    • journal article
    • research article
    • Vol. 7  (1) , 72-80
Abstract
Immunocytopathologic studies were performed on 79 fine needle aspiration biopsies (FNAB) and effusions from 13 melanomas and 57 other human neoplasms with the monoclonal antibody (MAb) D6.1 raised against a partially purified melanoma-tumor-associated antigen (MTAA). The purposes of these studies were to evaluate the ability of MAb 6.1 to react with melanoma cells in cytopathologic preparations and to define the spectrum of reactivity of MAb D6.1 in cytopathologic preparations of nonmelanomas. Cytocentrifuge preparations of the cytopathologic specimens were permitted to react with the primary antibody and were then stained by the avidin-biotin-immunoperoxidase method. Thirteen of 13 FNAB of malignant melanomas exhibited staining reactivity with MAb D6.1. Among the non-melanoma tumors tested, staining reactivity was observed in 30 of 57 specimens. Among specific neoplasms, staining was present in 5 of 11 adenocarcinomas of the breast, 2 of 7 ovarian adenocarcinomas and 5 of 6 metastatic adenocarcinomas from the colon. Among 17 lung cancers examined, staining was noted in 4 of 7 adenocarcinomas, 3 of 4 large-cell undifferentiated carcinomas and 2 of 3 poorly differentiated squamous-cell carcinomas. Two small-cell undifferentiated carcinomas and 1 carcinoid failed to stain. Three of 3 adenocarcinomas of the pancreas showed staining. Among the remaining neoplasms examined, 1 specimen each of carcinoma of the prostate and the cervix and 1 carcinoma of undetermined primary exhibited staining. Two malignant lymphomas did not stain. Staining of mesothelial cells was observed in 3 of 9 benign effusions. A comparison of the reactivity of MAb D6.1 between cytopathologic preparations and frozen-section histologic sections of melanomas and other nonmelanoma tumors showed a broad general agreement between the staining results obtained in frozen-section material and in cytopathologic preparations. In properly prepared cytopathologic specimens, MAb D6.1 demonstrated the presence of MTAA in all melanomas tested. MAb D6.1, while highly selective for melanomas over other tumors, did not demonstrate a tumor-associated antigen specific for melanoma. MAb D6.1 demonstrated MTAA as well in the cellular preparations as in the tissues themselves. MAb D6.1 has potential usefulness as a diagnostic adjunct in the major diagnostic dilemma posed by metastatic undifferentiated cancer. Its demonstrated ability to highlight MTAA in cytopathologic specimens and in FNAB in particular should prove to be a powerful enhancement of the information already provided by these techniques.