Fan Zhang1, Yan X Russell2, Helena A Guber3. 1. Division of Endocrinology, Diabetes & Metabolism, Veterans Affairs New York Harbor Healthcare System, Brooklyn Campus, 800 Poly Place, Brooklyn, New York; Division of Endocrinology, Diabetes & Metabolism, State University of New York, Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, New York; Division of Endocrinology, Diabetes & Metabolism, Brookdale University Hospital Medical Center, 1 Brookdale Plaza, Brooklyn, New York. Electronic address: fzhang8886@gmail.com. 2. Division of Endocrinology, Diabetes & Metabolism, Veterans Affairs New York Harbor Healthcare System, Brooklyn Campus, 800 Poly Place, Brooklyn, New York; Division of Endocrinology, Diabetes & Metabolism, State University of New York, Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, New York. 3. Division of Endocrinology, Diabetes & Metabolism, Veterans Affairs New York Harbor Healthcare System, Brooklyn Campus, 800 Poly Place, Brooklyn, New York.
Abstract
BACKGROUND: The high prevalence of thyroid nodules demands accurate assessment tools to avoid unnecessary biopsies. Prior studies demonstrated a correlation between the longitudinal location of thyroid nodules and the likelihood of malignancy. No study has evaluated the predictive value of transverse location on ultrasonography with malignancy. METHODS: We retrospectively reviewed the records of thyroid nodules that underwent fine-needle aspiration over 13 years, including demographics, risk factors, nodule sonographic features, location, and surgical pathology. Univariate and multivariable logistic regression models were used to evaluate the risk of malignancy. RESULTS: Of the 668 thyroid nodules, 604 were analyzed with a definitive diagnosis. Thirty-seven nodules were malignant, representing a prevalence of 6.1%. In the longitudinal plane, the upper pole nodules carried the highest incidence of malignancy (14.9%). In the transverse plane, the highest incidence of malignancy occurred in nodules located laterally (12.5%) and anterior-laterally (11.8%). Compared with the upper pole, the odds of malignancy were significantly lower for lower pole (odds ratio [OR] = 0.26, 95% confidence interval [CI]: 0.09-0.70) and midlobe nodules (OR = 0.31, 95% CI: 0.12-0.83). In the transverse plane, posteriorly situated nodules carried a significantly lower risk of malignancy (OR = 0.07, 95% CI: 0.01-0.69). Multiple logistic regression confirmed these associations after adjusting for age, sex, family history, radiation exposure, nodule size, and sonographic characteristics. CONCLUSION: Both the transverse and longitudinal planes were independent predictors of cancer in thyroid nodules. Lateral, anterior-lateral, and upper pole nodules carried the highest risk and posterior nodules had the lowest risk of malignancy.
BACKGROUND: The high prevalence of thyroid nodules demands accurate assessment tools to avoid unnecessary biopsies. Prior studies demonstrated a correlation between the longitudinal location of thyroid nodules and the likelihood of malignancy. No study has evaluated the predictive value of transverse location on ultrasonography with malignancy. METHODS: We retrospectively reviewed the records of thyroid nodules that underwent fine-needle aspiration over 13 years, including demographics, risk factors, nodule sonographic features, location, and surgical pathology. Univariate and multivariable logistic regression models were used to evaluate the risk of malignancy. RESULTS: Of the 668 thyroid nodules, 604 were analyzed with a definitive diagnosis. Thirty-seven nodules were malignant, representing a prevalence of 6.1%. In the longitudinal plane, the upper pole nodules carried the highest incidence of malignancy (14.9%). In the transverse plane, the highest incidence of malignancy occurred in nodules located laterally (12.5%) and anterior-laterally (11.8%). Compared with the upper pole, the odds of malignancy were significantly lower for lower pole (odds ratio [OR] = 0.26, 95% confidence interval [CI]: 0.09-0.70) and midlobe nodules (OR = 0.31, 95% CI: 0.12-0.83). In the transverse plane, posteriorly situated nodules carried a significantly lower risk of malignancy (OR = 0.07, 95% CI: 0.01-0.69). Multiple logistic regression confirmed these associations after adjusting for age, sex, family history, radiation exposure, nodule size, and sonographic characteristics. CONCLUSION: Both the transverse and longitudinal planes were independent predictors of cancer in thyroid nodules. Lateral, anterior-lateral, and upper pole nodules carried the highest risk and posterior nodules had the lowest risk of malignancy.