MATERIALS AND METHODS: This study included 50 cases of thyroid lesions (20 cases of colloid goitre, 15 of follicular adenoma, 5 of follicular carcinoma and 10 papillary carcinomas). Digital images of cytologic smears of these cases were captured using a dedicated photomicrography system and nuclear profiles traced manually. With self-designed image analysis software, nuclear morphometric measurements, including texture analysis, were performed. Discriminant analysis was performed including the morphometric parameters and percentage of correctly classified nuclei noted.
RESULTS: Nuclear morphometry parameters showed that papillary thyroid carcinoma had the highest perimeter, area, radius and elongation factor compared to other thyroid lesions. Discriminant analysis revealed that altogether 77.9% of cells could be correctly classified to their lesion category based on the nuclear morphometric and textural parameters. Of the neoplastic cases, 84.5% of cells of follicular neoplasms and 72.5% of papillary carcinoma were classified to the respective category.
CONCLUSION: Nuclear morphometry, including texture analysis, can assist in the cytologic diagnosis of thyroid lesions, considering the high degree of accuracy of classification. Further studies and methodological refinements can achieve higher accuracy.
MATERIALS AND METHODS: Immunohistochemical analysis of 60 thyroidectomy specimens (10 hyperplastic nodules, 14 follicular adenomas and 36 malignant thyroid neoplasms) was carried out. The extent and intensity of HBME-1, CK19, and S100 immunoreactivity was assessed in each case.
RESULTS: HBME-1 positivity was noted in 86.1% of malignant cases while the majority of the benign lesions were negative. Diffuse strong CK19 positivity was documented in 27/31 papillary carcinoma whereas all cases of follicular carcinoma and medullary carcinoma were negative. Most of the hyperplastic nodules and follicular adenomas were also CK19 negative, although focal weak staining was noted in a few cases. S100 was positive only in medullary carcinoma. HBME-1 was most sensitive (86.1%) and specific (87.5%) in distinguishing between benign and malignant thyroid lesions. The diagnostic accuracy was further increased when HBME-1 was used simultaneously with CK19/S100/CK19+S100. The sequential use of HBME-1 and CK19 also proved beneficial in discriminating between the various follicular-patterned thyroid lesions.
CONCLUSION: HBME-1 immunolabeling suggests malignancy, whereas strong diffuse CK19 positivity substantiates papillary differentiation. The utilization of these markers (alone or in combination) along with histomorphological evaluation is helpful in the differential diagnosis. S100 has minimal utility in this regard.