Crystalloids in submandibular sialadenitis.

Fine needle aspiration cytology of the salivary glands plays an important role in the diagnosis of neoplastic and non neoplastic lesions of salivary gland. Crystalloids in salivary gland lesions are a rare occurrence. A case of submandibular sialomegaly in an elderly patient with a clinical suspicion of metastasis was subjected to FNAC which showed crystalloids morphologically resembling amylase occurring in a background of sialadenitis. These crystals are non birefrigent, eosinophilic structures with a variety of geometric shapes including needles, rods, rectangular structures that do not stain with mucin stains. Other important crystalloids which can be observed in neoplastic and non-neoplastic salivary gland lesions are tyrosine-rich crystalloids, collagenous crystalloids, and oxalate crystals. These can be distinguished both morphologically and on the basis of several staining techniques in addition to biochemical studies. FNAC plays a major role in the diagnosis of these lesions and helps in avoiding unnecessary surgery.