Title: Statistical Measures of Performance of Positivity of Single and Multiple Grey Scale Ultrasound Features Favouring Malignancy, in Sonologically Confirmed Solitary Nodules of The Thyroid
Authors: S. Mangalanandan, N.J. John, K.K. Raishad Khan, S. Beenamol
DOI: https://dx.doi.org/10.18535/jmscr/v5i12.162
Abstract
Introduction: Incidence of malignancy is higher among solitary nodules of thyroid than multinodular disease. There are not many studies quantifying the statistical measures of performance of test criteria of presence of individual gray scale features favouring malignancy in solitary nodules. This study attempts to quantify them and to derive policies to recruit solitary nodules for FNAC.
Aim of the work: (1) To estimate the statistical measures of the performance of each of gray scale ultrasound features as a test criterion to identify malignancy in solitary thyroid nodules. (2) To see if a combination of ultrasound features which when present simultaneously will be more ‘positively predictive’/ ‘specific’ than individual features.
Patients and Methods: 40 cases of sonologically confirmed solitary nodules were selected from cases referred as ‘solitary nodule’ after palpation. The statistical measures of the performance of each of gray scale ultrasound features namely hypoechogenicity of a non-cystic nodule, microcalcifications, irregular margin and anteroposterior diameter equal to or more than transverse diameter, as a test criterion to identify malignancy in solitary nodules were calculated.
Results: When considered in isolation, each of the gray scale ultrasound features suggestive of malignancy has relatively low sensitivity in the setting of sonologically confirmed solitary nodules, though each of them has high specificity. The test criterion of presence of any one of the gray scale ultrasound features has a sensitivity of 100%.
Conclusions: All the solitary nodules with any one positive gray scale ultrasound feature should undergo FNAC. Simultaneous presence of any two or moresonologic features gives high levels of specificity and PPV; nodules should be considered highly suspicious.
Keywords: Solitary thyroid nodule, recruitment for FNAC, A/T ratio
References
- Kim DI ,Lee JT et al. New sonographic criteria for recommending fine-needle aspiration biopsy of nonpalpable solid nodules of the thyroid. AJR Am J Roentgenol. 2002; 178:687-691.
- Khoo ML, Asa SL, Witterick IJ, Freeman JL. Thyroid calcification and its association with thyroid carcinoma. Head Neck. 2002; 24:651-655.
- Papini E, Guglielmi R, Bianchini A. Risk of malignancy in nonpalpable thyroid nodules: predictive value of ultrasound and color Doppler features. J Clin Endocrinol Metab 2002; 87:1941-1946.
- Peccin S, de Castro JA, Furlanetto TW, Furtado AP, Brasil BA, Czepielewski MA et al. Ultrasonography: is it useful in the diagnosis of cancer in thyroid nodules? J Endocrinol Invest 2002; 25:39-43
- Frates MC, Benson CB, Charboneau JW, Cibas, Clark OH , Coleman BG et al. Likelihood of thyroid cancer based on sonographic assessment of nodule size and composition [abstr]. In: Radiological Society of North America Scientific Assembly and Annual Meeting Program. Oak Brook, In: Radiological Society of North America, 2004; 395
- Frates MC, Benson CB, Doubilet PM, Cibas ES, Marqusee E.Can Doppler sonography aid in the prediction of malignancy of thyroid nodules? J Ultrasound Med.2003;22:127-131
- Koike E, Noguchi S, Yamashita H. Ultrasonographic characteristics of thyroid nodules: Prediction of malignancy. Arch Surg. 2001; 136:334-337.
- Cappelli C, Pirola I, Cumetti D, Micheletti L, Tironi A, Gandossi E. et al. Is the anteroposterior and transverse diameter ratio of nonpalpable thyroid nodules a sonographic criteria for recommending fine-needle aspiration cytology? ClinEndocrinol (Oxf). 2005 ; 63:686-93.