The utility of Touch Imprint Cytology in Diagnosis of Oral Squamous Cell Carcinoma –University of Nairobi, School of Dental Sciences

Abstract

Oral squamous cell carcinoma (OSCC) is an aggressive neoplasm with limited therapeutic options and poor survival rates. Assessment of surgical margins in OSCC during intra-operative procedure is important and influences its local recurrence, patient’s survival rates, management and overall prognosis. Currently histopathology technique is being used as a gold standard; it is reliable but time consuming while touch imprint cytology is cheap and quick technique useful where rapid results are required. The objective of this study was to evaluate the utility of touch imprint cytology in assessing OSCC in comparison with histopathology. A descriptive cross-sectional study of 73 participants with suspected oral squamous cell carcinoma was conducted, whereby on analysis 69 of the samples were diagnostic. Touch imprints were done and results were compared with histopathology. Data was analyzed using SPSS version 17.0 and descriptive summary statistics done were presented as proportions and percentages in the form of tables and charts where relevant. The level of agreement between the diagnostic techniques was calculated using the chi-square test and kappa statistics. A p value less than 0.05 was considered statistically significant. The most participants were male (71%) and the highest age being 50-59 years. The most common site of lesion was tongue (43.5%) and cytomorphology pattern most demonstrated was a singly dispersed cell pattern. There were 53 true positives, 12 false negatives and 4 true negatives and no false positive. The sensitivity, specificity, positive predictive value, negative predictive value and the overall accuracy were 81.5%, 100%, 100% and 25% respectively with an overall accuracy of 90.75% and with a kappa level agreement of 53% between touch imprint cytology and histopathology and a p-value of 0.033 which is statistically significant. Touch imprint cytology is therefore a sensitive technique which can be useful in screening and reliable where rapid preliminary diagnosis is needed in the surgical management; it is also an affordable technique for developing countries with limited resource.. We recommend sampling from multiple sites should be applied while preparing touch imprints to increase harvesting of malignant cells from biopsies. Touch imprint cytology requires practice and experience and should be adopted in pathology routine work to enable technical staff develop and acquire expertise.