Salivary gland manifestations of sinus histiocytosis with massive lymphadenopathy: fine-needle aspiration cytology findings. A case report.

Sinus histiocytosis with massive lymphadenopathy (SHML or Rosai-Dorfman disease) is a nonneoplastic, usually self-limiting disease. Alhough it affects all age groups, it is more commonly seen in young males in their first or second decades. The disease primarily manifests as painless lymphadenopathy of cervical region, but other nodal groups and extranodal sites may also be affected. Seldom SHML may involve the salivary glands. We present the cytologic features and differential diagnoses of one such case.A 45-yr-old woman presented with an enlarged submandibular gland on the left side with ipsilateral cervical lymphadenopathy that had been persisting for 1 mo. The gland and the two enlarged nodes measured 2.5 x 2.5 cm(2) each and were firm in consistency. Clinically, tumor of the salivary glands was suspected. Fine-needle aspiration (FNA) smears showed moderate cellularity, with large histiocytes dispersed in the background of intense lymphoplasmacytic infiltrate. These histiocytes showed lymphophagocytosis. Isolated stromal fragments consisting of fibrocytes were seen separate from salivary acinar clusters on repeat aspirations. The diagnosis of SHML involving left submandibular gland and ipsilateral lymph nodes was returned. When analyzed in the context of clinical findings (laboratory data), the cytologic features of SHML involving salivary gland could be differentiated from those of malignancies and other benign lesions, especially Kuttner's tumor of the submandibular gland, which mimics neoplasm clinically.