Abstract
Purpose
Video-assisted lateral neck dissection (VALND) for papillary thyroid carcinoma (PTC) with lateral neck lymph node metastases (LNM) has been described previously, however, the advantages and drawbacks of VALND have not been demonstrated in previous studies. The aim of this study was to compare the surgical outcomes of video-assisted and open lateral neck dissection for PTC with lateral neck LNM.
Materials and methods
Between May 2013 and November 2014, 92 consecutive patients with PTC and lateral neck lymph node metastases underwent total thyroidectomy with central compartment neck dissection and unilateral lateral neck dissection. These included 54 individuals who underwent video-assisted surgery, and 38 in whom an open approach was used. The two groups were retrospectively compared with respect to their clinicopathological characteristics, surgical outcomes and oncological completeness.
Results
The mean follow-up period was 18.6 months. The mean tumor size, tumor stage, mean numbers of retrieved lymph nodes, mean postoperative serum thyroglobulin levels, complication rates, and mean postoperative hospital stay were similar between the two groups. The mean operation time was longer (p = 0.0001) and mean age was lower (p = 0.0354) in the video-assisted group. The cosmetic results, evaluated by numerical scale and verbal response scale, were in favor of the video-assisted group (p = 0.0003 and p < 0.0001, respectively).
Conclusions
The safety and oncological completeness of VALND was similar to that of open procedures, but the VALND resulted in improved cosmetic results. VALND is an effective treatment for the selected cases of PTC with lateral neck LNM.
1
Introduction
Papillary thyroid carcinoma (PTC) is the most common type of thyroid malignancy and is the most likely to metastasize to the regional lymph nodes . Therapeutic lateral neck dissection (LND) is recommended in patients with clinical evidence of lymph node involvement of the lateral neck compartment . Although open LND is the standard approach, it inevitably yields poor cosmetic results, due to a long scar on the neck. To avoid producing a long anterior neck scar in PTC patients, several studies have used video-assisted LND (VALND), and the feasibility of VALND has been confirmed , but the advantages and drawbacks of VALND have not been demonstrated in previous studies. In this study, we compared the surgical outcomes between VALND and open LND for PTC with lateral neck lymph node metastases (LNM).
2
Materials and methods
2.1
Patients
We retrospectively assessed a cohort of consecutive patients with PTC and lateral neck LNM who underwent total thyroidectomy with central compartment neck dissection (CCND) and unilateral LND at the Head and Neck Surgery Department of SIR RUN RUN SHAW Hospital, Institute of Micro-Invasive Surgery of Zhejiang University from May 2013 to November 2014. Of those patients, 54 underwent a video-assisted (VA) approach and 38 underwent an open approach. Preoperative diagnoses and staging were revealed by ultrasonography (US), computed tomography (CT), and ultrasound-guided fine needle aspiration biopsy (FNAB) examination. The presence of lateral neck LNM was determined by ultrasound-guided FNAB and histology examinations preoperatively. Levels II, III, IV and Vb dissection were performed routinely in all cases. Before inclusion into the study, patients had to meet certain inclusion and exclusion criteria. The inclusion criteria were: (1) primary tumor size ≤4.0 cm, (2) largest diameter of the metastatic lymph node ≤2.5 cm, and (3) ≤2 levels LNM in the lateral neck compartment by US and CT examinations preoperatively. The exclusion criteria were: (1) a history of previous neck surgery; (2) metastatic lymph nodes at level I or Va; (3) ≥3 levels of LNM in the lateral neck compartment by US and CT examinations preoperatively; and (4) primary tumor or metastatic lymph node invasion into major vascular structures, the trachea, or the esophagus. The choice of VA or open approach was made on patients’ cosmetic demands and economic status. All patients signed a written informed consent form, and our institutional review board approved this study.
2.2
Surgical procedures
Under general endotracheal anesthesia, patients were placed in a supine position with the neck slightly extended by a roll placed beneath the shoulders and a small donut placed under the occiput to stabilize and support the head.
2.2.1
VALND procedure
A single 4-cm to 5-cm transverse incision was made in the central region of the neck about 1-finger breadth above the sternal notch, in the natural skin folds. After a total thyroidectomy and CCND were performed under a direct visual field approach, the patient’s head was turned to the opposite side from the lesion to expose the lateral neck compartment area, and LND was performed via the VA approach. The procedures used for VALND were similar to those reported by Lombardi et al. and Miccoli et al. , but with some modifications. The first is the working space creation technique. In China, a self-developed working space creator (Hangzhou Good Grams Photoelectric Instrument Co. Ltd., Hangzhou, China) has been invented and widely used for minimally invasive VA thyroidectomy (MIVAT) . Based on our experience with MIVAT, we have used this working space creator in the VALND procedure. Instead of having an assistant using manual retraction to create space, the working space creator can mechanically elevate the upper skin flap and keep the working space stable for a long time. The second technique used is a negative-pressure suction device that is attached to the long retractor (Hangzhou Good Grams Photoelectric Instrument Co. Ltd., Hangzhou, China), supplying continuous suction to remove the steam that was generated by the Harmonic scalpel (Ethicon Endo-Surgery, Cincinnati, OH, USA), to ensure clear visibility during surgery ( Fig. 1 A, B ). An upper flap was created and lifted using the self-developed working space creator consisting of a long retractor fitted with a suction apparatus. The tent-like working space created in this way provided a large, stable area for simultaneous insertion of a 10-mm, 30-degree endoscope and surgical instruments through the same skin incision. The steam generated by the Harmonic scalpel was cleared immediately using the continuous negative-pressure suction apparatus connected to the long retractor. Then, the medial border of the sternocleidomastoid muscle (SCM), with fascia, was dissected and retracted by one long retractor. Another long retractor could be repositioned as needed, depending on the dissection location ( Fig. 2 ). The carotid sheath was opened, and the internal jugular vein (IJV) and carotid artery were exposed between the carotid bifurcation (cranially) and the subclavian vessels (caudally). The IJV was retracted medially with a long retractor, the vagus nerve was exposed, and the lymph nodes and surrounding fibroadipose tissue were retracted and dissected downward. The spinal accessory nerve (SAN), cervical plexus, phrenic nerve, and brachial plexus were exposed and preserved, as was the transverse cervical artery. The thoracic duct on the left side or the right lymphatic duct could be identified and preserved in some cases due to the magnification provided by the endoscope; they were ligated safely when necessary. The lateral neck lymph nodes were resected en bloc ( Fig. 3 ).
2.2.2
Open LND procedure
A 9-cm to 12-cm extended collar incision was made along the natural skin fold about one finger breadth above the sternal notch. The skin flap was made to the hyoid bone superiorly, the superior edge of the clavicle inferiorly, and the anterior edge of the trapezius posteriorly. After a total thyroidectomy and CCND, the patient’s head was turned to the opposite side of the lesion to improve the exposure of the lateral neck compartment area. Then, the medial border of the SCM with fascia was dissected and retracted laterally. The carotid sheath was opened, and the IJV and carotid artery were exposed between the carotid bifurcation (cranially) and subclavian vessels (caudally). The SAN, cervical plexus, phrenic nerve, and brachial plexus were exposed and preserved, along with the transverse cervical artery. The lateral neck lymph nodes were resected en bloc.
2.3
Postoperative follow-up
All patients were treated with 100 mCi radioactive iodine (RAI) from 2 to 4 months postoperatively. All patients also received suppressive levothyroxine therapy. Direct or indirect laryngoscopy was performed preoperatively and postoperatively to assess vocal cord function. Serum thyroglobulin (sTg) and thyroglobulin antibody levels were measured every 6 months after surgery. Ultrasonography was performed to assess the thyroid bed and lateral neck compartment every 6 months after surgery. Cosmetic results were evaluated on a numerical scale and a verbal response scale . The numerical scale ranged from 0 to 10, with a higher score indicating a better cosmetic result. The verbal response scale included four options: 1 = poor; 2 = acceptable; 3 = good; and 4 = excellent. All patients were asked to grade the cosmetic appearance of their skin incision at 1 year after surgery.
2.4
Statistical analysis
Statistical analysis was conducted using Statistical Analysis System, version 9.0 (SAS Inc., Cary, NC, USA). The results were expressed as mean ± standard deviation (SD). Statistical significance was defined as p < 0.05.
2
Materials and methods
2.1
Patients
We retrospectively assessed a cohort of consecutive patients with PTC and lateral neck LNM who underwent total thyroidectomy with central compartment neck dissection (CCND) and unilateral LND at the Head and Neck Surgery Department of SIR RUN RUN SHAW Hospital, Institute of Micro-Invasive Surgery of Zhejiang University from May 2013 to November 2014. Of those patients, 54 underwent a video-assisted (VA) approach and 38 underwent an open approach. Preoperative diagnoses and staging were revealed by ultrasonography (US), computed tomography (CT), and ultrasound-guided fine needle aspiration biopsy (FNAB) examination. The presence of lateral neck LNM was determined by ultrasound-guided FNAB and histology examinations preoperatively. Levels II, III, IV and Vb dissection were performed routinely in all cases. Before inclusion into the study, patients had to meet certain inclusion and exclusion criteria. The inclusion criteria were: (1) primary tumor size ≤4.0 cm, (2) largest diameter of the metastatic lymph node ≤2.5 cm, and (3) ≤2 levels LNM in the lateral neck compartment by US and CT examinations preoperatively. The exclusion criteria were: (1) a history of previous neck surgery; (2) metastatic lymph nodes at level I or Va; (3) ≥3 levels of LNM in the lateral neck compartment by US and CT examinations preoperatively; and (4) primary tumor or metastatic lymph node invasion into major vascular structures, the trachea, or the esophagus. The choice of VA or open approach was made on patients’ cosmetic demands and economic status. All patients signed a written informed consent form, and our institutional review board approved this study.
2.2
Surgical procedures
Under general endotracheal anesthesia, patients were placed in a supine position with the neck slightly extended by a roll placed beneath the shoulders and a small donut placed under the occiput to stabilize and support the head.
2.2.1
VALND procedure
A single 4-cm to 5-cm transverse incision was made in the central region of the neck about 1-finger breadth above the sternal notch, in the natural skin folds. After a total thyroidectomy and CCND were performed under a direct visual field approach, the patient’s head was turned to the opposite side from the lesion to expose the lateral neck compartment area, and LND was performed via the VA approach. The procedures used for VALND were similar to those reported by Lombardi et al. and Miccoli et al. , but with some modifications. The first is the working space creation technique. In China, a self-developed working space creator (Hangzhou Good Grams Photoelectric Instrument Co. Ltd., Hangzhou, China) has been invented and widely used for minimally invasive VA thyroidectomy (MIVAT) . Based on our experience with MIVAT, we have used this working space creator in the VALND procedure. Instead of having an assistant using manual retraction to create space, the working space creator can mechanically elevate the upper skin flap and keep the working space stable for a long time. The second technique used is a negative-pressure suction device that is attached to the long retractor (Hangzhou Good Grams Photoelectric Instrument Co. Ltd., Hangzhou, China), supplying continuous suction to remove the steam that was generated by the Harmonic scalpel (Ethicon Endo-Surgery, Cincinnati, OH, USA), to ensure clear visibility during surgery ( Fig. 1 A, B ). An upper flap was created and lifted using the self-developed working space creator consisting of a long retractor fitted with a suction apparatus. The tent-like working space created in this way provided a large, stable area for simultaneous insertion of a 10-mm, 30-degree endoscope and surgical instruments through the same skin incision. The steam generated by the Harmonic scalpel was cleared immediately using the continuous negative-pressure suction apparatus connected to the long retractor. Then, the medial border of the sternocleidomastoid muscle (SCM), with fascia, was dissected and retracted by one long retractor. Another long retractor could be repositioned as needed, depending on the dissection location ( Fig. 2 ). The carotid sheath was opened, and the internal jugular vein (IJV) and carotid artery were exposed between the carotid bifurcation (cranially) and the subclavian vessels (caudally). The IJV was retracted medially with a long retractor, the vagus nerve was exposed, and the lymph nodes and surrounding fibroadipose tissue were retracted and dissected downward. The spinal accessory nerve (SAN), cervical plexus, phrenic nerve, and brachial plexus were exposed and preserved, as was the transverse cervical artery. The thoracic duct on the left side or the right lymphatic duct could be identified and preserved in some cases due to the magnification provided by the endoscope; they were ligated safely when necessary. The lateral neck lymph nodes were resected en bloc ( Fig. 3 ).
