Nuclear Morphometry as an Adjunct to Cytomorphology in the Diagnosis of Thyroid Lesions

Abstract

Introduction: Fine Needle Aspiration Cytology (FNAC) is a reliable and reproducible diagnostic technique for thyroid lesions. Recently, it has been suggested that evaluation of nuclear features may enhance the diagnostic utility of FNAC. However, the evaluation of nuclear morphometry is not well established in thyroid cytology. Aim: To evaluate the role of nuclear morphometry in cytological evaluation of thyroid lesions. Materials and Methods: This was a cross-sectional study conducted over a period from March 2019-February 2020 at Hamdard Institute of Medical Sciences and Research, New Delhi, India. Morphometry was done on 40 cases of thyroid aspirates which had histopathological concordance. Computerised nuclear morphometry was done by using photographs captured under Motic photomicrography system. Six parameters were measured- nuclear area, nuclear perimeter, minimal nuclear diameter, maximal nuclear diameter, nuclear compactness and LS ratio (Largest to Smallest dimension ratio). Data were entered in spreadsheet and then analysed using Statistical Package for Social Sciences (SPSS) version 20.0. Results: Out of total 40 thyroid aspirates studied, included non neoplastic (19 cases), benign (12 cases) and malignant lesions (9 cases). All nuclear morphometry parameters comprising of nuclear area, nuclear perimeter, minimal nuclear diameter, maximal nuclear diameter showed an increasing trend from non neoplastic to benign to malignant with a statistically significant difference between benign and malignant groups (p-values <0.05) except for LS ratio and nuclear compactness. Conclusion: Nuclear morphometry can aid in cytological diagnosis of thyroid lesions. If used judiciously, quantitative estimation of cytological nuclear features can be helpful in assessing thyroid lesions preoperatively thus complementing its cytomorphological features.