Diagnostic Accuracy, Sensitivity, Specificity and Positive Predictive Value of Fine Needle Aspiration Cytology (FNAC) in Intra Oral Tumors

Abstract


Objective: The objective of this study was to establish the diagnostic accuracy, specificity and sensitivity of fineneedle aspiration cytology(FNAC) for intra-oral tumors, comparing with histopathology as the gold standard.Materials and methods: Forty cases of FNA cytology from intraoral tumors was performed in AFID along withthe demographic data and clinical information and then diagnosed at AFIP, Rawalpindi. Then the cytologyresults obtained per FNAC were compared with the histopathological biopsy results of the same lesions. Thefollowing variables were recorded for each patient: Age, gender, site of biopsy, diagnosis. The data were enteredand analyzed using Open-epi version 2.0. Diagnostic accuracy, sensitivity, specificity, positive predictive value andnegative predictive value were calculated. Cohen Kappa was further applied to compare the agreement betweenthe biopsy and FNAC diagnoses. A p-value of < 0.05 was considered as statistically significant.
Results: Among thetotal patients included in the study there were 24 males and 16 females, with a ratio of 1.5:1. Age of the patientsranged from 24 to 80 years with a mean of 52 years. A total of six sites were aspirated from the oral cavity withmaximum (11) aspirates taken from alveolar ridge. The results of FNAC revealed that there were 32 malignantand 8 benign aspirates. Confirmation through histopathological analysis came for 31/32 malignant cases whileone was falsely given positive for malignancy on FNAC. Among a total of 40 cases, 31(77%) cases diagnosed werefound to be malignant and remaining 9(23%) were benign. The FNAC results revealed 32 malignant and 8 benignlesions. Histopathology of the subsequent surgically excised specimen showed malignant lesions in 31(77%) andbenign in 9(23%) patients. As a whole, it was found that the absolute sensitivity for introral FNAC was 100%and specificity 89% with positive predictive value of 97% and negative predictive value of 100%.
Conclusion:Cytological diagnosis was almost corroborative with final histopathological diagnosis in all cases, with very fewexceptions, exhibiting high diagnostic accuracy.

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