Diagnostic dilemma of parotid lipomas: imaging versus fine needle aspiration cytology

Abstract

Lipomas are common soft tissue neoplasms; however, they are found rarely in the parotid gland region. The purpose of this study was to analyze the diagnostic challenges of this rare condition. We performed a retrospective analysis of 11 patients with parotid lipomas, treated from November 2009 to February 2014. The mean age at diagnosis was 46.6 ± 2.9 years, and the study population included 8 males and 3 females. Computed tomography (CT) and/or magnetic resonance imaging (MRI) were performed in radiological diagnosis. Fine needle aspiration (FNA) was performed in all cases (including two times in five patients, for a total of 16 biopsies) and results were diagnostic in four instances. Specificities of the CT, MRI, and FNA cytology tests were 100%, 100%, and 25% respectively. CT and/or MRI scans were more reliable than FNA cytologies for accurate diagnosis of parotid lipomas.

The risk of malignancy according to Milan reporting system of salivary gland fine‐needle aspiration with Becton Dickinson SurePath liquid‐based processing

“…They consisted of 44,4% of the cases in the ND category diagnosed by histological examination. Arslan et al analyzed 11 patients with parotid lipomas and found high ND cytology rates for lipomas. The high ND ratio in all salivary gland FNAs in the current study may be related to sampling error, or the nature of the lesion (eg, cystic and lipoma).…”

Intraluminal tracheal lipoma as a rare cause of dyspnoea in a dog

“…However, cytology did not provide accurate diagnosis of tumour type, possibly because the capsule surrounding the lipoma was not penetrated during sampling. Similarly, Arslan et al [ 30 ] has reported that FNA was diagnostic in only four of 11 people with parotid lipoma. The major advantage of forceps biopsies is that the specimens are suitable for histological examination.…”

“…However, it has been shown that CT is more sensitive in detecting pulmonary metastasis than radiography and in our case a CT examination would have provided valuable information on possible lymph node or lung metastasis, enabled sampling of these lesions and would have displayed the extent of the tumour outside endoscopically visible trachea [ 26 – 28 ]. Additionally, in this case CT examination could have raised a suspicion of lipoma by demonstrating tissue density typical for fat [ 29 , 30 ]. CT was not performed in our patient because of financial constraints.…”

Differential Diagnosis of Parotid Lipoma in a Breast Ca Patient

“…It can also be performed for identification of free nodal lesions, localization of the masses within salivary glands, and differentiation of congenital vascular lesions from the lymph nodal chain [ 1 , 7 ]. Contrast-enhanced high resolution CT is another useful radiological technique in differential diagnosis [ 10 ]. While a positive density is observed in normal parotid tissue, a well-demarcated hypodense density (−50 to −150 Hounsfield units) can be identified in lipomatous tissue in contrast-enhanced images [ 1 , 10 ].…”

“…Contrast-enhanced high resolution CT is another useful radiological technique in differential diagnosis [ 10 ]. While a positive density is observed in normal parotid tissue, a well-demarcated hypodense density (−50 to −150 Hounsfield units) can be identified in lipomatous tissue in contrast-enhanced images [ 1 , 10 ]. In MRI examinations, lipomas show a similar signal intensity with subcutaneous fat, characterized by a high T1 and low T2 signal intensity [ 10 ].…”