Immunohistochemical study with antibody to glycoprotein GCDFP-15 for metastatic lung cancer from breast cancer

Even when gross pathologic specimens are available, evaluation is always co mplicated due to the difficulty in distinguishing the pathologic diagnosis of an adenocarcinoma as a pulmonary metastasis of the breast or lung. in th is paper, we describe the usefulness of a preoperative immunohistochemical study using gross cystic disease fluid protein-15 (GCDFP-15). A 50-year-old woman, who had undergone a right radical mastectomy due to an infiltrating ductal carcinoma 4 years previously, was admitted because of an abnormal s hadow on chest roentgenograpy. A chest CT scan showed a nodule 20 min in diameter with an irregular margin and vascular involvement in the S-3 region of the right lung. Though the s pecimen from a percutaneous CT guided needle biopsy revealed characteristic pathologic findings of a primary lung adenocarcinoma under H.E. stain, whi ch was recommended for lobar resection, we re-examined that specimen inummo histochemically, which disclosed that the tumor cells were negative for the antibody to pulmonary surfactant apoprotein and were positive for GCDFP-15 antibody. Therefore, the diagnosis of a metastatic breast carcinoma in the lung was e stablished. Upon her request, a wedge resection of the right upper lobe inc luding the tumor was performed under video-assisted thoracoscopic surgery ( VATS). Her postoperative course was uneventful.