Sonographic and Clinical Features of Papillary Thyroid Microcarcinoma Less than or Equal to Five Millimeters: A Retrospective Study

Abstract

ObjectiveTo retrospectively compare the sonographic and clinical features of papillary thyroid microcarcinoma (PTMC) ≤5 mm and PTMC >5 mm to improve the diagnostic value of ultrasonography.MethodsA total of 367 cases of PTMC between January 2013 and December 2014 was included in this study. The patients were classified into group A (≤5 mm, n = 181) or group B (>5 mm, n = 186), and the sonographic and clinical features were reviewed and compared between the two groups.ResultsThere was no significant difference in the shape, ratio of length/width, boundary, peripheral halo ring, echogenicity, cystic change and accompanying Hashimoto's thyroiditis between these two groups. However, the calcification (61.3% vs. 72.6%) and hypervascularity (13.8% vs. 24.7%) were more frequent in group B (p = 0.026 and 0.008, respectively). The patients were younger, and more patients were aged less than 45 years (41.4% vs. 57.0%) in group B. Capsular invasion (7.2% vs. 34.4%), multifocality (21.5% vs. 48.9%), bilaterality (17.1% vs. 39.8%), central lymph node metastasis (13.8% vs. 38.2%) and lateral lymph node metastasis (1.1% vs. 5.4%) were more frequent in group B. No clinical or sonographic feature was related to cervical lymph node metastasis in group A, while less than 45 years in age (p = 0.010), male gender (p = 0.040), capsular invasion (p<0.001), multifocality (p = 0.016) and calcification (p = 0.042) were related to cervical lymph node metastasis in group B.ConclusionsThe sonographic features of PTMC ≤5 mm were similar to those of PTMC >5 mm, including an irregular shape, a length/width ratio of ≥1, an unclear boundary, no peripheral halo ring, hypoechogenicity, no cystic change, calcification, no hypervascularity and no accompanying Hashimoto's thyroiditis. The clinical features of PTMC ≤5 mm were less aggressive than those of PTMC >5 mm.

Association of sonographic features and clinicopathologic factors of papillary thyroid microcarcinoma for prevalence of lymph node metastasis: a retrospective analysis

“…T hyroid carcinoma measuring 1 cm or less in its greatest dimension is considered as thyroid microcarcinoma (1). Papillary thyroid microcarcinoma is the most common form of thyroid microcarcinoma (2). It is associated with the risk of lymph node metastasis (1,3) and exhibits aggressive behavior (2).…”

“…Papillary thyroid microcarcinoma is the most common form of thyroid microcarcinoma (2). It is associated with the risk of lymph node metastasis (1,3) and exhibits aggressive behavior (2). However, low-risk papillary microcarcinomas have excellent oncological outcomes of active surveillance (4).…”

“…A retrospectively studies reported that lymph node metastasis frequency is higher in multifocal papillary thyroid microcarcinoma with higher sized nodules (1,5,10). The other retrospective study reported that clinicopathologic factors of papillary thyroid microcarcinoma of 5 or less mm diameter (Ø) nodules were less aggressive than more than 5 mm Ø nodules (2). A retrospectively studies reported that preoperative more than 65 pg/mL serum levels of calcitonin, subcapsular locations and the size of nodules are associated with lymph node metastasis (6,10).…”

The thyroid cancer policy model: A mathematical simulation model of papillary thyroid carcinoma in The U.S. population

“…For a person to be detected, there must exist a nodule greater than 3 mm, which represents a conservative limit of sonographic technology [19–21]. The model input parameters (prior to calibration) are shown in Table 1.…”

Indolent thyroid cancer: knowns and unknowns

“… Additional factors were not predictive. Lai et al [ 55 ] 2016 367 PTC ≤1.0 cm ETE LN mets Size, shape, length/width ratio, border, peripheral halo, echogenicity, cystic change, calcification (any), vascularity, presence of Hashimoto’s thyroiditis Size associated with LN mets and ETE. Calcification (any), multifocality associated with LN mets only for microcarcinoma > 5 mm.…”