Immunohistochemical study of adrenocortical carcinoma. Predictive value of the D11 monoclonal antibody

The diagnosis of adrenocortical carcinoma (ACC) may be difficult with conventional light microscopy, especially when the tumor is nonfunctioning. Until now, no specific adrenocortical tumor marker was available. The current study was undertaken to investigate the interest of the D11 MoAb for the diagnosis and prognosis of ACC.

Eighteen adrenocortical carcinomas, 10 primary adrenomedullary tumors, 20 primary hepatocellular carcinomas, 50 primary renal cell carcinomas, 5 primary lung carcinomas, and 18 intraadrenal metastases were analyzed immunohistochemically with the D11 monoclonal antibody. ACC were also evaluated for the expression of other tumor markers, including neuron-specific enolase, chromogranin A, S-100, Leu-7, vimentin, KL1, AE1AE3, and epithelial membrane antigen. Relationships between clinical features and results of immunohistochemistry were also sought.

Nuclear D11 staining appears to be highly specific for normal adrenocortical cells and related tumors. Nuclear D11 positivity was demonstrated in 44% of ACC and was restricted to well-differentiated tumors. No cytoplasmic or nuclear D11 staining was observed in adrenomedullary tumors. D11 reactivity confined to the cytoplasm was found in 5 of 18 adrenal metastases, in all 20 hepatocellular carcinomas tested, in 3 of 5 lung carcinomas, and in 1 of 50 primary renal cell carcinomas. Patients with nuclear D11 immunostaining were initially seen with metastases less often and survived longer than those with no nuclear D11 immunostaining (P < 0.05).

Nuclear D11 immunoreactivity may help to differentiate ACC from intraadrenal metastases and adrenomedullary tumors. This also selects a group of ACC patients with a more favorable outcome.