Oncocytic papillary cystadenoma of parotid gland: A diagnostic challenge on fine‐needle aspiration cytology

Abstract

Oncocytic papillary cystadenomas (OPC) of the head and neck are rare tumors. They have been reported in accessory tear glands, minor salivary glands of buccal mucosa, soft palate and lip, nasopharynx, larynx, and infrequently in parotid glands. [1][2][3][4][5][6][7][8] The lesion tends to occur more frequently in women; most patients are older then 50 years of age. 9 The usual presentation is an asymptomatic mass present for several years before diagnosis. 3 The biological behavior of this tumor is similar to that of Warthin's tumor. Recurrences are unusual and probably represent mutifocality. 10 The cytological features of this lesion have not been well documented in literature, and histopathology is mandatory to arrive at a final diagnosis. 1,7,[11][12][13][14][15][16] A 75-year-old male presented with a slightly painful swelling in right upper posterior cervical region, just below the angle of mandible, slowly increasing in size over a year. On examination, the swelling measured 2.5 cm in diameter, was firm, slightly tender, and mobile. The patient gave the history of root abscess in the 2nd right lower molar tooth and took antibiotics for it off and on. He was referred for fine-needle aspiration (FNA) with a clinical diagnosis of lymphadenitis. FNA was performed on two occasions at an interval of 1 week. Both times whitish turbid fluid was aspirated. The smears were air dried for Giemsa staining and wet fixed for Papanicolaou (Pap) staining. Smears from the first aspirate revealed a necrotic inflammatory background with presence of scattered atypical squamous cells including an occasional orangeophilic cell with pyknotic nucleus, tadpole and fibre cells on Pap stain (Fig. 1). The differential diagnoses considered were cystic squamous cell carcinoma, branchial cyst, infracted pleomorphic adenoma, and infracted Warthin's Tumor. As there was no obvious primary malignancy and the patient was clinically well preserved, a second FNA from a different site was advised after a course of antibiotics. This aspirate showed a different picture, comprising of many vacuolated cells, some containing pinkish mucinous material and some with a signet ring appearance (Fig. 2). In addition, there were a few atypical squamous cells and an occasional multinucleated giant cell with atypical hyperchromatic nuclei against a mucoid inflammatory background (Fig. 3). The differential diagnoses offered included mucoepidermoid tumor, Warthin's tumor, and cystic adenosquamous carcinoma. The CT scan of head and neck region performed at this time revealed a circumscribed swelling in the lower pole of parotid gland. The swelling was excised under local anaesthesia and on histopathology; a diagnosis of oncocytic papillary cystadenoma of parotid gland was returned (Fig. 4). There were no mucin-containing cells or features of squamous malignancy on histopathology sections. Because of these noncorrelating features on histology, the FNA smears were reviewed. No characteristic oncocytic cells or papillary structures were found in the smears even on ...

Papillary cystadenoma of the parotid gland: A case report

“…Our study of 700 patients with salivary gland tumors during 2010 to 2016 found only one patient (female) with PGPC, which accounted for about 0.14% of all study tumors and about 0.15% of benign study tumors. We listed the reported cases of PGPC with comparatively complete data between 2009 and 2018 in Table 1[3,14-17], while solely retrospective studies without detailed data were excluded. Because of the rarity of cystadenoma of the salivary glands, the gender ratio of patients remains unclear and the etiopathogenesis of this disease has not been well discussed in textbooks and other published articles.…”

Nodular oncocytic hyperplasia: Can cytomorphology allow for the preoperative diagnosis of a nonneoplastic salivary disease?

“…Only 2 FNA specimens in the current series of oncocytosis cases demonstrated moderate cellularity, with single cells found to be present in just 1 case. The cytologic features of papillary oncocytic cystadenoma have been described only rarely, but more complex papillary architecture and psammoma bodies have been noted than were observed in any oncocytosis FNA specimen, although both can have a cystic background. Of course, a suboptimal specimen from any of these lesions could produce a specimen similar to these oncocytosis cases, thereby limiting the ability to make a definitive diagnosis within this differential.…”

Oncocytic papillary cystadenoma of major salivary glands: Three rare cases with diverse cytologic features

“…Gupta et al . [9] described somewhat different cytologic findings from two FNAs taken from the same OPC, with either atypical squamous cells in a necrotic background, consistent with squamous cell carcinoma, or many vacuolated and signet ring cells in a mucoid background. No oncocytic cells or papillary features were seen in either aspirate.…”