Tumor size measured by preoperative ultrasonography and postoperative pathologic examination in papillary thyroid carcinoma: relative differences according to size, calcification and coexisting thyroiditis

Abstract

Ultrasonography (US) is a useful diagnostic modality for evaluation of the size and features of thyroid nodules. Tumor size is a key indicator of the surgical extent of thyroid cancer. We evaluated the difference in tumor sizes measured by preoperative US and postoperative pathologic examination in papillary thyroid carcinoma (PTC). We reviewed the medical records of 172 consecutive patients, who underwent thyroidectomy for PTC treatment. We compared tumor size, as measured by preoperative US, with that in postoperative specimens. And we analyzed a number of factors potentially influencing the size measurement, including cancer size, calcification and coexisting thyroiditis. The mean size of the tumor measured by preoperative US was 11.4, and 10.2 mm by postoperative pathologic examination. The mean percentage difference (US-pathology/US) of tumor sizes measured by preoperative US and postoperative pathologic examination was 9.9 ± 19.3%, which was statistically significant (p < 0.001). When the effect of tumor size (≤10.0 vs. 10.1-20.0 vs. >20.0 mm) and the presence of calcification or coexisting thyroiditis on the tumor size discrepancy between the two measurements was analyzed, the mean percentage differences according to tumor size (9.1 vs. 11.2% vs. 9.8%, p = 0.842), calcification (9.2 vs. 10.2%, p = 0.756) and coexisting thyroiditis (17.6 vs. 9.5%, p = 0.223) did not show statistical significance. Tumor sizes measured in postoperative pathology were ~90% of those measured by preoperative US in PTC; this was not affected by tumor size, the presence of calcification or coexisting thyroiditis. When the surgical extent of PTC treatment according to tumor size measured by US is determined, the relative difference between tumor sizes measured by preoperative US and postoperative pathologic examination should be considered.

Diagnostic Accuracy of Preoperative Radiologic Findings in Papillary Thyroid Microcarcinoma: Discrepancies with the Postoperative Pathologic Diagnosis and Implications for Clinical Outcomes

“…A subgroup analysis of 34 PTMCs revealed no significant differences; however, 18.8% of nodules that measured larger than 1 cm on USG were found to be smaller than 1 cm on pathology [ 18 ]. Yoon et al [ 19 ] included 172 PTCs (100 PTMCs) in their study and found that the pathologic tumor size was 10% smaller than the sonographic size. Hahn et al [ 15 ] studied 490 PTCs (272 PTMCs) and observed that preoperative USG tended to overestimate the size of tumors, especially those smaller than 1.0 cm.…”

Discrepancies between the ultrasonographic and gross pathological size of papillary thyroid carcinomas

“…In their study, however, both benign and malignant thyroid nodules with diverse histologic diagnoses were included in the study population. Yoon et al [ 10 ] reported that papillary carcinoma sizes measured postoperatively were consistently significantly smaller than the US-estimated sizes, with a mean percentage difference of 9.9%. However, although they evaluated differences in the size of the individual tumors measured by preoperative US and postoperative pathology, they did not assess the significance of agreement between the measurement methods.…”

Re: Tumor size measured by preoperative ultrasonography and postoperative pathologic examination in papillary thyroid carcinoma: relative differences according to size, calcification and coexisting thyroiditis

“…We recently read with interest an article ''Tumor size measured by preoperative ultrasonography and postoperative pathologic examination in papillary thyroid carcinoma: relative differences according to size, calcification and coexisting thyroiditis'' [1], published in European Archives of Oto-Rhino-Laryngology. To begin with, we appreciate the authors' efforts paid in this original article.…”