Clinical Behavior and Outcome of Papillary Thyroid Cancers Smaller than 1.5 cm in Diameter: Study of 299 Cases

Abstract

To investigate predictors of relapse in small (<or=1.5 cm) papillary thyroid cancers, we performed a retrospective chart review study of patients treated and followed up in our institution according a standard prospective protocol. Between 1975 and 2001, 299 patients were operated for a differentiated papillary thyroid cancer no larger than 1.5 cm in size. Near-total or total thyroidectomy was performed in 292 patients, and lobectomy in seven patients.Persistent/recurrent disease was observed in 77 patients; in 37 of these patients, the only sign was increased TSH-stimulated serum thyroglobulin (Tg). Ten patients developed distant metastases, and 68 locoregional metastases. At multivariate analysis, persistent/recurrent disease was associated with: 1) nonincidental thyroid cancer; 2) lymph node metastases at presentation; and 3) bilateral tumor. Development of distant metastases was associated with the sclerosant variant and the presence of lymph node metastases at presentation. Tumor size (<or=1.0 cm vs. 1.1-1.5 cm) was not predictive of relapse. No patient died because of the disease, but 14.4% had evidence of disease at their last follow-up visit. Serum Tg level below 1.0 ng/ml at the first postsurgical evaluation during l-T(4) withdrawal was an accurate predictor of no relapse. In conclusion, approximately one of four patients with a papillary thyroid cancer no more than 1.5 cm in size develops relapsing/persisting disease after surgery. Baseline histopathological characteristics and serum Tg levels off l-T(4) at first postsurgical evaluation can accurately predict the risk of relapse.

T1a Versus T1b Differentiated Thyroid Cancers: Do We Need to Make the Distinction?

“…The datasets used in the present study lack information regarding recurrence. However, other longitudinal institutional studies have shown no difference in recurrence rates between T1a and T1b tumors at five years (10,11), and up to 15 years following the time of diagnosis (16)(17)(18).…”

S100A4 expression is associated with lymph node metastasis in papillary microcarcinoma of the thyroid

“…Moreover, some authors have insisted that there was no statistically significant difference between papillary microcarcinomas and papillary thyroid carcinomas at clinical follow-up. 11,24 Thus, establishing the predictive factors that differentiate between silent and potentially aggressive papillary microcarcinomas would be of great value. S100A4 is a member of the S100 family of calcium-binding proteins, also known as metastasin, fibroblast-specific protein, pEL-98, 18A2, CAPL or calvasculin.…”

“…8 Although its clinical significance in papillary microcarcinomas is somewhat controversial, several authors have reported that lymph node metastasis at presentation is correlated with loco-regional recurrence in papillary microcarcinomas. 5,[9][10][11] Moreover, lymph node metastasis is reported to be associated with distant metastasis of papillary microcarcinomas. [9][10][11] In the new TNM (tumor, node, metastases) staging system, lymph node metastasis is a more important factor than tumor size in overall staging.…”

“…5,[9][10][11] Moreover, lymph node metastasis is reported to be associated with distant metastasis of papillary microcarcinomas. [9][10][11] In the new TNM (tumor, node, metastases) staging system, lymph node metastasis is a more important factor than tumor size in overall staging. 12 Overexpression of cyclin D1, 13 S100A4 14 and MUC1, 15 loss of p27 13,16 and presence of the BRAF mutation 17,18 have been suggested as important predictive factors for relapse or nodal metastasis of papillary thyroid carcinoma.…”

Recommendations of the Latin American Thyroid Society on diagnosis and management of differentiated thyroid cancer

“…Others, however, have concluded that, in low-risk patients, the incremental benefit of remnant ablation is unclear (22). Patients with papillary microcarcinoma receive ablation, especially when multicentricity, lymph node metastases and vascular or capsular invasion are encountered (23).…”