Comparison of Preoperative Fine-needle Aspiration Cytology Diagnosis and Histopathological Diagnosis of Salivary Gland Tumors

Abstract

We investigated 115 patients with salivary gland epithelial tumors who had undergone preoperative fine needle aspiration cytology (FNAC) of salivary glands and had been diagnosed by postoperative histopathological examination. We compared the findings of preoperative FNAC with their histopathological types in salivary gland tumors, and discuss the results and problems. The diagnostic accuracy, sensitivity, and specificity of preoperative FNAC of salivary glands were 98.2%, 88.2%, and 100%, respectively. The percentage of inadequate specimens was 6.1%. The rates of agreement in the diagnosis of pleomorphic adenoma, Warthin tumor, and basal cell adenoma were 96%, 92.9%, and 55.5%, respectively. The rate of agreement of histopathological types in the malignant tumors was 30%. We realized again not only that the diagnostic accuracy of preoperative FNAC for salivary gland tumors was high, but also that it was a safe, easy-to-perform, clinically very useful diagnostic procedure. However, this study exposed several problems which are the inadequate sampling rate and the difficulty in diagnosing malignant tumors. We have been making efforts to take appropriate specimens by writing comments on the cytological report indicating a re-examination, or by the presence of the clinical laboratory technician at the FNAC procedure. We consider it necessary to adequately re-aspirate the solid portion after cyst fluid aspiration, or to re-perform FNAC at a later date, and to improve the diagnostic accuracy by further experience with more patients.

Accuracy of Fine Needle Aspiration Cytology of Salivary Gland Lesions: Routine Diagnostic Experience in Bangkok, Thailand

“…Sampling error is the major factor that led to false-negative result in this case. We agree with prior studies that the sufficient specimen can improve the diagnostic accuracy (Jayaram et al, 2004;Mihashi et al, 2006). Recently study concluded that there were four reasons for incorrect interpretation in cytological diagnosis of salivary gland including inadequate sampling or insufficient specimens, marked cellular degeneration, error of labeling specimens and cytologist unfamiliar with the morphology of rare salivary gland lesion (Jan et al, 2008).…”

“…In our study, the diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of preoperative FNA cytology of salivary gland lesions were 97%, 81.3 %, 99.1%, 92.9%, and 97.5% respectively, indicating good results compared with those previously reported from other institutions (O'Dwyer et al, 1986;Frable & Frable, 1991;Chan et al, 1992;Zurrida et al, 1993;Al-Khafaji et al, 1998;Boccato et al, 1998;Mihashi et al, 2006;Tan & Koo, 2006). Nevertheless, other studies have reported wide variation in sensitivity and specificity of FNA cytology of salivary gland in detecting malignant tumors, ranging from 29% to 97% and 84% to 100%, respectively (reviewed in Cohen et al, 2004).…”

“…Previous study reported that using FNA as an initial diagnostic tool have been able to reduce the number of operative procedures on salivary gland lesions approximately 30% (Qizilbash et al, 1985) and some patients do not receive invasive treatment (Mavec et al, 1964). The unsatisfactory specimens in this study was 5.2% which was relatively low as had been reported in the literatures (Cadillo, 1990;Layfield & Glasgow, 1991;Jayaram et al, 1994;Boccato et al, 1998;Tan & Koo, 2006;Mihashi et al, 2006, Jan et al, 2008, vary from 3% to 12%. The difference range may occur from sampling method, experience of clinician who perform adequate specimen, without the aid of cytopathologist (Boccato et al, 1998).…”

“…In our institution, FNA is routinely used as a practical method et al, 1997; Cristallini et al, 1997;Frable & Frable, 1991;Chan et al, 1992;Das et al, 2004, Mihashi et al, 2006.…”

“…Previous studies reported the diagnostic performance of FNA in salivary gland lesions; the sensitivity was in the range of 62-100%; specificity of 86-100% and accuracy of 77-98.2% respectively (O'Dwyer et al, 1986;Frable & Frable, 1991;Chan et al, 1992;Zurrida et al, 1993;Al-Khafaji et al, 1998;Boccato et al, 1998;Mihashi et a., 2006;Tan & Koo, 2006). It is widely used in America, Europe and Asia (Layfield et al, 1987;Frable and Frable, 1991;Chan et al, 1992;Zurrida et al, 1993;Stanley et al, 1995;Al-Khafaji et al, 1998;Mihashi et al, 2006;Tan & Koo, 2006). Nevertheless, this procedure has been questioned for the diagnostic value in management of salivary gland tumors and may not cost-effective in routine cytology work for every patient (Batsakis et al, 1992;Tan & Koo, 2006).…”