Cytologic examination and carcinoembryonic antigen assay of fine needle aspirates of bone tumors.

A prospective study of 28 consecutive fine needle aspirates of bone was conducted comparing the sensitivities of cytologic diagnosis with carcinoembryonic antigen (CEA) content to determine if the CEA assay could enhance the sensitivity of cytologic diagnosis of carcinoma metastatic to bone. Aspirates obtained radiologically or at surgery underwent cytologic examination and CEA assay. Cytologic examination was performed on Papanicolaou-stained smears and/or cell blocks. CEA was measured with an enzyme immunoassay; 5 ng/mL was used as the cutoff. Twenty-one were malignant and seven benign. The sensitivities of cytology and CEA were 85% and 47.6%, respectively, and the specificities, 100%. Mean CEA and sensitivity were highest for adenocarcinoma of lung (361.5 ng/mL, 77%), lowest for carcinoma of breast and negative for lymphoma, myeloma and benign aspirates. High CEA was useful in (1) suggesting adenocarcinoma of lung in patients with an unknown primary, (2) suggesting a new primary lung adenocarcinoma in a patient with previous transitional cell carcinoma of bladder, and (3) discriminating lung adenocarcinoma from adenocarcinomas of kidney, thyroid, prostate or endometrium.