Superior mediastinal dissection for papillary thyroid carcinoma: approaches and outcomes

Clinical outcomes of combined cervical and transthoracic surgical approaches in patients with advanced thyroid cancer

BACKGROUND

Advanced thyroid disease involving the mediastinum may be managed surgically with a combined transcervical and transthoracic approach. Contemporary analysis of this infrequently encountered cohort will aid the multidisciplinary team in personalizing treatment approaches.

METHODS

Retrospective review of patients undergoing combined transcervical and transthoracic surgery for thyroid cancer at a single high-volume institution from 1994 to 2015.

RESULTS

Thirty-eight patients with median age 59 years (range 28-76) underwent surgery without perioperative mortality. Most patients had primary disease. A majority had distant metastases outside the mediastinum but had locoregionally curable disease. Common complications were temporary (39%) and permanent (18%) hypoparathyroidism, and wound infection (13%). One-year overall survival was 84%; 1-year locoregional disease-free survival was 64%. Median time to locoregional recurrence was 36 months. Only esophageal invasion was associated with worse oncologic outcomes.

CONCLUSIONS

Combined transcervical and transthoracic surgery for advanced thyroid cancer can be performed without mortality and with acceptable morbidity.

Surgical indications for upper mediastinal dissection by sternotomy in patients with papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is a relatively indolent disease, despite the high incidence of lymph node metastases. Although less frequent, some upper mediastinal metastases of PTC cannot be removed without sternal resection. In this study, we investigated the prognostic impact of upper mediastinal dissection (UMD) by sternotomy on patients with mediastinal metastases of PTC. Charts of patients with PTC who underwent surgical treatment at our institution between 2006 and 2018 were retrospectively reviewed. Fifty-eight patients with upper mediastinal metastases were enrolled. Kaplan-Meier survival curves were compared, and Cox hazard regression models were used for analyses. Of the 58 patients with mediastinal metastasis, 12 (20.7%) underwent dissection of the prevascular nodes, 51 (87.9%) underwent dissection of the upper paratracheal nodes, and 14 (24.1%) underwent dissection of the lower paratracheal node. The preferred site of mediastinal metastasis was the upper paratracheal nodes. The 5 and 10-year disease-specific survival rates for patients after UMD were 74.6% and 58.7%, respectively. Among 25 patients (43.1%) with locoregional recurrence, 12 (20.7%) had mediastinal recurrence and 7 were eligible for additional UMD. Although distant metastasis was the predominant poor prognostic factor, mediastinal recurrences were more frequently unresectable than cervical recurrences, suggesting that mediastinal recurrence is a poor prognostic factor. Mediastinal metastases larger than 30 mm or metastases to the lower paratracheal nodes are considered a risk factor for mediastinal recurrence. UMD by sternotomy for patient with upper mediastinal metastases which are difficult to resect via transcervical approach is an effective treatment option to improve patient prognosis.

Video-assisted superior mediastinal lymphadenectomy for papillary thyroid cancer: a case report

Superior mediastinal lymph node metastases in papillary thyroid cancer are uncommon. The clinical characteristics and surgical strategy of superior mediastinal lymph node metastases remain unclear. Superior mediastinal lymphadenectomy can be accomplished either by a transcervical or transsternal approach. Transsternal approach for superior mediastinal lymphadenectomy can cause great damage; transcervical approach sometimes results in inadequate exposure. Here we report our experience of a papillary thyroid cancer patient with superior mediastinal lymph node metastases who underwent video-assisted superior mediastinal lymphadenectomy. A 49-year-old woman diagnosed with papillary thyroid cancer in left thyroid underwent unilateral lobectomy and ipsilateral central and lateral node dissection in the local hospital 4 years ago. Currently lymph node metastases were found in mediastinum and the right neck, some of which were adjacent to the right innominate vein. Unilateral lobectomy, ipsilateral central and lateral node dissection, and video-assisted superior mediastinal lymphadenectomy were successfully performed by transcervical approach. Subsequently, the patient received thyroxine suppression therapy and adjuvant radioiodine treatment. Video-assisted superior mediastinal lymphadenectomy, providing adequate exposure for a complete superior mediastinal lymphadenectomy, is proved to be safe and feasible.

Mediastinal Lymph Node Metastases in Thyroid Cancer: Characteristics, Predictive Factors, and Prognosis

BACKGROUND

Mediastinal lymph node metastases (MLNM) have not been extensively studied. The aim of this study is to investigate the characteristics, predictive factors, and prognosis of MLNM in thyroid cancer.

METHODS

This is a retrospective study based on the thyroid cancer patients with MLNM at our institution from 2008 to 2015.

RESULTS

In total, 73 thyroid cancer patients with positive MLNM were included in this study. It contained sixty patients (82.2%) with papillary thyroid carcinoma (PTC), twelve (16.4%) with medullary thyroid carcinoma, and one (1.4%) with anaplastic thyroid carcinoma. Forty-eight patients had the surgery as initial treatment. Fifty-three (72.6%) patients remained disease-free, and fifteen (20.5%) developed a regional recurrence. Distant metastases occurred in four (5.5%) patients and five (6.8%) patients died. Five-year overall survival rate and disease-free survival (DFS) rate of the PTC patients for initial treatment are 95.4% and 77.2%, respectively. Extrathyroidal extension and multiple lymph nodes involved were associated with DFS in PTC patients.

CONCLUSIONS

Initial therapeutic control is very important for the thyroid cancer patients. Extrathyroidal extension and multiple mediastinal lymph nodes involved were the influence factors of prognosis in the thyroid cancer patients with MLNM.

Predictive Factors of Superior Mediastinal Nodal Metastasis from Papillary Thyroid Carcinoma--A Prospective Observational Study

OBJECTIVES

The purpose of this study was to demonstrate the incidence rates and predictive factors of superior mediastinal lymph node (SMLN) metastasis in PTC (papillary thyroid carcinoma) patients.

METHODS

A prospective observational study was performed between January 2009 and January 2011. PTC patients who had tumors with a maximal diameter greater than 1 cm and clinically negative SMLNs were included in this study. Finally, a total of 217 patients who underwent total thyroidectomy with central compartment neck dissection (CND) and elective superior mediastinal lymph node dissection (SMLND), with or without modified radical neck dissection (MRND) and revisional CND, were included.

RESULTS

Occult SMLN metastasis was present in 15.7% (34/217). Cytological classifications of tumor, BRAFV600E mutation, Tumor size, T-stage, perithyroidal extension, lymphovascular invasion, multifocality, and paratracheal pN(+) were not predictive of SMLN metastasis (P > .05), while revision surgery, pretracheal pN(+), and multiple lateral pN(+) were associated with SMLN metastasis. There were no major complications related to SMLND. Transient and permanent hypoparathyroidism was observed in 69 cases (31.8%) and 8 cases (3.6%), respectively.

CONCLUSIONS

Despite clinically negative SMLN in preoperative evaluation, SMLN metastasis can be predicted for patients with a PTC tumor size larger than 1 cm, pretracheal LN metastasis, multiple lateral metastasis, and revisional surgery.