Salivary duct carcinoma (cribriform salivary carcinoma of excretory ducts). A clinicopathologic and immunohistochemical study of 12 cases.

Salivary duct carcinoma (cribriform salivary carcinoma of the excretory ducts [CSCED]) is an uncommon malignant tumor which occurs predominantly in men (83% in this series; mean age, 61 years) and most often in the parotid gland (92% in this series). The outcome is unfavorable for most patients; of 11 of 12 patients with follow-up, 45% had local recurrence, 54% had distant metastasis, and 45% were dead of disease within 10 years of diagnosis (mean, 3 years). Metastases to lymph nodes were common (72%). Immunohistochemical studies on paraffin-embedded tissue revealed that most tumors reacted with antibodies known to mark adenocarcinoma: B72.3 (11 of 11) and Lewis Y (ten of ten). High and low molecular weight cytokeratins were present in most tumors (nine of ten and seven of nine cases, respectively), supporting the concept that these adenocarcinomas were of ductal origin. Parotid ducts adjacent to CSCED expressed B72.3 in six of nine cases studied, but parotid ducts from normal tissue (adjacent to benign mixed tumors or enlarged periparotid lymph nodes) rarely expressed this marker (one of 17 cases). The detection of B72.3 diffusely in parotid ducts, especially those with atypia, may imply the presence of malignant tumor nearby, which could be useful in evaluating limited tissue from the parotid. However, further studies are necessary to confirm the significance of this finding.