Histologic and fine-needle aspiration cytologic features of polycystic disease of the parotid glands: case report and review of the literature

Polycystic disease of the parotid glands is a rare disorder, with only eight examples to our knowledge being reported in the literature. The disease presents as a painless enlargement of one or both parotid glands and does not appear to be associated with other disease processes within the head and neck, or with polycystic disease of the kidney, pancreas, or congenital fibrosis of the liver. The histology has been well described. The overall glandular architecture is preserved but the lobules are markedly distended by cysts whose lining appears to be intercalated duct in differentiation. Characteristic eosinophilic laminated spheroliths lie in many of the cystic spaces. Aspirate smears are characterized by a relatively clean background in which are distributed histiocytes, red blood cells, and small clusters of ductal epithelial cells. Polycystic disease of the parotid glands must be differentiated cytologically from mucous retention reaction, mucoceles, benign lymphoepithelial cysts, and cystic neoplasms, including Warthin's tumor, low-grade mucoepidermoid carcinoma, cystadenoma, and papillary cystadenocarcinoma.     

Cystic lesions of the salivary glands: cytologic features in fine-needle aspiration biopsies

A variety of neoplastic and nonneoplastic lesions of the salivary glands have a predominantly cystic architecture. Fine-needle aspirates of these lesions yield watery or mucoid material, frequently of low cellularity. Such aspirates may be obtained from mucus retention cysts, lymphoepithelial cysts, cystadenomas, Warthin's tumors, cystic pleomorphic adenomas, low-grade mucoepidermoid carcinomas, cystadenocarcinomas, and examples of polycystic disease of the parotid gland. The cellular component within the fluid obtained from these lesions may be exceedingly scant or absent, making cytologic diagnosis difficult and, at times, impossible. We studied a series of 56 cystic lesions of the salivary glands, including 38 Warthin's tumors, 6 benign cysts, 2 lymphoepithelial cysts, 5 low-grade mucoepidermoid carcinomas, 1 cystic pleomorphic adenoma, 2 cystadenomas, and 2 cystadenocarcinomas. Careful attention to the cellular elements present often allowed definitive cytologic diagnosis, with an overall accuracy rate of 84%. The presence of atypical squamous metaplasia in oncocytic lesions was a significant cause of false-positive diagnoses of carcinoma (4 cases, 7%). Aspirates of low-grade mucoepidermoid carcinoma may contain no epithelial cells and result in false-negative diagnoses (1 case, 2%).     

Cellular adequacy for thyroid aspirates prepared by ThinPrep: How many cells are needed?

Although it is well established that ThinPrep introduces artifacts to thyroid aspirates, no criteria have been established for adequacy of such specimens. This study evaluates the adequate number of cells needed to establish the correct diagnosis based on ThinPrep alone. A total of 218 thyroid aspirates prepared by TP with surgical pathology follow-up were reviewed. The cellularity was calculated as follows: Count the total number of clusters, randomly select 10 clusters and count each, calculate the average number per cluster and multiply by the total number of clusters. A minimum number of 6 clusters with 10 cells each was arbitrary established to assume adequacy for a definitive diagnosis. Cytologic diagnoses were classified as: Nondiagnostic (ND), cystic contents, thyroiditis, nodular hyperplasia (NH), follicular/Hurthle (F/H) cell lesion, F/H cell neoplasm, and carcinoma: qualify. Histologic diagnoses were classified as: Cyst (colloid or otherwise), thyroiditis, NH, F/H adenoma, F/H carcinoma, carcinoma: qualify. Appropriate treatment triage was considered to be clinical for the former 4 cytologic categories and surgical for the latter 3 with ND warranting repeat aspiration. The results were subjected to logistic regressions analysis and contingency tables correlating the number of cells with the cytologic and histologic diagnosis as well as with treatment triage. Cellularity of sample was ranked in 10 deciles according to the number of cells and in 4 quartiles according to the number of clusters. The agreement percentage, for both diagnostic and treatment, was computed for each decile and quartile. 146 (67%) cases had cells and received a diagnosis while 72 (33%) were acellular. Of the 146 cases, 21 contained histiocytes or colloid only. 91/146 (62.3%) were correctly diagnosed and 123/146 (84.3%) would have been correctly triaged for treatment based upon the cytologic diagnosis. Samples with 180 cells or fewer had an agreement rate below 50%. Agreement rate increases to 80% when cellularity is 180-320. Above 320 agreement rate remains high but not uniformly. Total number of clusters did not play an independent role and only the number of cells per cluster had a significant correlation with diagnostic agreement. A 25-cell increase in average cells per cluster increases the odds of agreement between diagnoses by 65%.     

Is core needle biopsy superior to fine‐needle aspiration biopsy in the diagnosis of papillary breast lesions?

Since the 1980s core needle biopsy (CNB) has gained remarkable popularity and in many institutions it has replaced fine-needle aspiration biopsy (FNAB). However, similar to FNAB, limitation remains in the ability of this procedure to reliably diagnose a small, but prognostically significant, number of breast lesions. These include entities such as atypical ductal hyperplasia, fibro-epithelial tumors, radial scar, papillary lesions, and lobular neoplasia. To assess the diagnostic accuracy of CNB vs. FNAB in the same breast lesions, we reviewed our cases of papillary lesions of the breast. In a retrospective study, we identified 36 cases of FNAB and 11 cases of CNB diagnosed as papillary lesions and compared the results with their corresponding surgical specimen. Interpretation ranged from papillary vs. atypical papillary lesions favoring benign vs. malignant tumors, respectively. Occasionally, definitive diagnosis of papillary carcinoma was entertained. Immunohistochemical staining with smooth muscle actin was used to evaluate the presence or absence of a myoepithelial cell layer. FNAB had benign findings in 21 lesions, atypical in 10, and malignant in five. Of the five lesions yielding malignant features, four had invasive carcinoma and one had micropapillary ductal carcinoma in situ (DCIS). Surgery revealed invasive carcinoma in three of the cases interpreted as atypical papillary lesions and invasive cancer and micropapillary DCIS in three of the cases diagnosed as benign lesions. Similar results were obtained with CNB. DCIS was found in one out of six of the cases diagnosed as papilloma. Out of the four cases that were interpreted as atypical papillary lesion, surgery revealed invasive carcinoma in one case and one case had micropapillary DCIS. Diagnosis of malignancy was confirmed by histology in one case interpreted as papillary carcinoma by CNB. This study suggested that both FNAB and CNB share similar diagnostic challenges and a follow-up surgical excision is indicated when diagnosis of a papillary lesion is entertained by both procedures.     

Cytomorphology of cystic parathyroid lesions: Report of four cases evaluated preoperatively by fine-needle aspiration

Cystic parathyroid lesions (CPL) account for 1–5% of neck cysts. They are seldom palpable; however, they may present as neck swellings that are mistaken both clinically and cytologically for thyroid nodules and subsequently referred for evaluation by fine-needle aspiration. We present 4 cases of histologically confirmed CPL (one simple cyst, one hyperplasia, and two adenomas), 2 of which were misdiagnosed as adenomatoid thyroid nodules by fine-needle aspiration. Aspirated fluid from one patient was clear and colorless, a classic finding for parathyroid cysts, and contained high levels of C-terminal/midmolecule parathyroid hormone (CMPH). Fluids obtained from the remaining 3 patients were bloody to brown, resembling thyroid cyst fluid. In only 1 of the 3 patients, the fluid was analyzed and contained high levels of CMPH. Though cytologic features of parathyroid epithelium overlap with those of thyroid epithelium, distinguishing features such as unusual cytoplasmic vacuolization and granularity, and the absence of colloid, should raise suspicions of a parathyroid lesion. Fluid from CPL may not possess the classic appearance; however, identification of the subtler cytologic features with knowledge of relevant clinical data should prompt analysis of cyst fluid for CMPH, thus confirming the diagnosis and avoiding inappropriate therapy. Diagn Cytopathol 1996;15:306–311. © 1996 Wiley-Liss, Inc.