D Deplano

Larger tumor size predicts nodal involvement in patients with follicular thyroid carcinoma.

AIMS AND BACKGROUND Lymph node metastases are rare in patients with follicular thyroid carcinoma, with an average incidence of 5.5% of all cases reported in the literature. In the present study we focused on the search for risk factors predictive of lymph node involvement in patients with follicular thyroid carcinoma to plan the most appropriate management and follow-up. METHODS AND STUDY DESIGN We carried out a cross-sectional study among patients with follicular thyroid carcinoma and lymph node metastasis at diagnosis and patients without lymph node involvement. From January 1998 to April 2008, 930 patients underwent thyroidectomy in our surgical department for a variety of thyroid disorders, 420 (45.2%) of them for a differentiated thyroid carcinoma. The medical records of 55 patients with histological diagnosis of follicular thyroid carcinoma were analyzed. RESULTS Four patients (7.3%) had lymph node metastasis from follicular thyroid carcinoma at presentation in both the lateral and central neck compartments. Mean tumor size was significantly greater for follicular thyroid carcinomas with nodal metastasis (5.1 ± 1.4 cm) than for those without nodal involvement (3.0 ± 1.2 cm, P <0.010). Among factors supposed to influence the presence of nodal metastasis at diagnosis (age, gender, tumor size, multifocality, tumor poorly differentiated, tumor widely invasive, vascular invasion, thyroid capsular invasion, and extra thyroid invasion), tumor size larger than 4.0 cm was the only factor retained in the multivariate statistical model. CONCLUSIONS Lymph node dissection must be planned only in the case of large follicular thyroid carcinomas. Since follicular carcinoma is usually diagnosed postoperatively, more attention should be paid to nodal involvement in the tumor re-staging during follow-up of those patients with tumors larger than 4.0 cm in diameter.

Encapsulated papillary thyroid carcinoma: Is it a distinctive clinical entity with low-grade malignancy?

Background: Encapsulated papillary thyroid carcinoma (EPTC) is commonly retained as a tumor with indolent clinical courses. Herein we focused on the search for factors predicting biological behavior and influencing prognosis of EPTC in comparison with the non-encapsulated counterpart of papillary thyroid carcinoma (NEPTC). Methods: From January 1998 to May 2009, 348 patients underwent thyroidec-tomy in our surgical department because of papillary thyroid carcinoma (PTC). A cross-sectional study of 52 patients with EPTC and 296 patients with NEPTC was carried out: demographic data, tumor characteristics, diagnostic results, patient management, post-operative and follow-up results were evaluated. Results: EPTC patients were significantly younger than patients with NEPTC (44.5 vs 48.8 yr, p<0.04). Mean tumor size was significantly greater for EPTC than for NEPTC (2.36 vs 1.41 cm, p<0.001). Tumor multifocality, thyroid capsular invasion, and lymph node involvement at diagnosis were significantly associated with NEPTC (p=0.0001, p<0.0001, and p=0.027, respectively). Multivariate analyses showed that NEPTC classical variant were at risk for both thyroid capsular invasion and nodal involvement (odds ratio 6.870 and 9.514, respectively) while EPTC were not. Nodal metastasis at diagnosis was the only factor influencing recurrence. Conclusions: The majority of EPTC had risk-free clinical courses as a result of their low risk of locoregional spread. However, definitive recommendations need a longer follow-up and a comparison with a lesser treated group of patients belonging to the same category of risk at diagnosis.