Sialolithiasis:Differential Diagnostic Problems in Fine-Needle Aspiration Cytology

Abstract

Sialolithiasis with obstruction of major salivary gland ducts can lead to clinical tumefaction related to cystic dilatation. In addition to mucus accumulation, these pseudoneoplasms feature hyperplasia and squamous metaplasia of the ductal lining epithelium, with varying degrees of inflammation. The authors report five examples of this lesion aspirated from two males and three females ranging in age from 45 to 80 years (median 65 years). Three were in the submaxillary gland, and two were in the parotid. In three cases, stone fragments were identified, and diagnoses of sialolithiasis were rendered; two of these patients underwent surgical excision. The remaining two cases showed prominent foam cells and metaplastic squamous cells in a mucoid background that mim-The true incidence of sialolithiasis is difficult to determine, as many cases are apparently asymptomatic. Some examples are incidentally discovered at the time of dental radiography, but up to 20% are not radiopaque. K2Stone formation in the salivary glands (SG) is not associated with abnormalities of calcium metabolism. Those symptomatic cases that lack the clinical features of a secondary bacterial infection usually feature recurrent pain and swelling associated with meals. Many patients are symptomatic for years, and a few with large stones may describe nearly continuous pain. Sialolithiasis is most common in the submaxillary glands, with the parotid less commonly involved.'" 3 Fine-needle aspirations (FNA) from stone-bearing salivary gland are rarely reported. 4 Chronic salivary gland duct obstruction (of which sialolithiasis is one cause) leads to parenchymal atrophy,

Selected Problems in Fine Needle Aspiration of Head and Neck Masses

“…A particular case of the more generally described duct-obstructive lesion is sialolithiasis (23). The typical patient is female and has a submandibular gland swelling.…”

Fine Needle Aspiration Biopsy of Salivary Gland Lesions

“…40 In these cases the smears can demonstrate immature squamous metaplastic elements that strongly resemble the "intermediate" cells of low grade mucoepidermoid carcinoma. 41 Therefore, it is suggested that when FNAB findings consistent with a low grade mucoepidermoid carcinoma are encountered, the possibility of sialolithiasis should be considered. Not all cases will show stones in cytologic material or radiographs, and further clinical investigation may be warranted before the institution of surgical therapy.…”

Fine-needle aspiration cytology of mucous retention cyst of the tongue: Distinction from other cystic lesions of the tongue

“…Sparse cellularity seen in cases of low-grade MEC has been reported. 19,20 In contrast, aspirates from high-grade MEC generally show marked cytologic atypia, at times precluding the correct characterization of the tumor. 4 -6,9 Occasionally, other malignant neoplasms that typically affect major salivary glands may arise in the minor salivary glands of the floor of the mouth and tongue and may be cystic.…”