Abstract
The aim of this study was to evaluate the technical feasibility and safety of robot-assisted modified radical neck dissection (MRND) for head and neck cancer patients with a clinically node-positive neck. The cases of 10 head and neck cancer patients who underwent unilateral therapeutic robot-assisted MRND by post-auricular facelift approach were analyzed. The robot-assisted MRND was completed successfully in all patients without any conversion to conventional neck dissection. The mean number of lymph nodes removed was 36.7 ± 8.6. The mean duration of surgery for robot-assisted MRND was 274 ± 65 min (range 175–395 min). Transient marginal nerve palsy occurred in two patients and partial necrosis of the skin flap occurred in one patient. In terms of cosmetic satisfaction, 70% of patients were very satisfied or satisfied with postoperative cosmesis. In conclusion, robot-assisted MRND by post-auricular facelift approach is technically feasible and safe in selected patients with head and neck cancer, and yields excellent postoperative cosmesis.
Cervical lymph node metastasis is the single most adverse prognostic factor in head and neck cancer apart from distant metastasis. Neck dissection is the standard procedure for surgical treatment of clinical or occult cervical lymph node metastasis in head and neck cancer. Neck dissection has evolved from radical neck dissection (RND), to modified radical neck dissection (MRND), selective neck dissection (SND), and super-selective neck dissection, thereby minimizing surgical morbidity while obtaining comparable oncological outcomes.
Recently neck dissection using an endoscope or surgical robot via a remote site has been developed to hide visible neck scars for better cosmesis. Endoscopic and robotic neck dissection via a minimally invasive, video-assisted, transaxillary or breast approach was originally tried for thyroid cancer; following this, robotic neck dissection was also developed for head and neck cancer using a modified or post-auricular facelift approach.
At the authors’ institution, robotic lateral neck dissection for differentiated thyroid cancer has been performed via a gasless unilateral axillo-breast (GUAB) or axillary (GUA) approach, as well as robotic SND including levels I–III or II–V via a post-auricular facelift approach for head and neck cancer patients with a clinically negative neck, and their technical feasibility and safety have been reported. After gaining more experience and becoming familiar with the procedure, the robotic post-auricular facelift approach has since been expanded to MRND for head and neck cancer patients with a clinically node-positive neck.
The aim of this study was to evaluate the technical feasibility and safety of robot-assisted MRND in head and neck cancer patients with a clinically positive neck.
Materials and methods
Patients
The data of 10 head and neck cancer patients who underwent therapeutic unilateral MRND for a clinically node-positive neck by robot-assisted post-auricular facelift approach using the da Vinci Surgical System (Intuitive Surgical Inc., Sunnyvale, CA, USA), between October 2012 and January 2014, were analyzed.
The potential indication for robot-assisted MRND in the study institution is head and neck cancer with a clinically node-positive neck, for which transoral resection of the primary tumour using the da Vinci robot, a CO 2 laser, endoscopy, or conventional methods is to be performed. The contraindications are distant metastasis, massive invasion to adjacent structures from large conglomerate metastatic lymph nodes, and prior neck surgery or irradiation.
Positive cervical lymph node metastasis was found in all patients by physical examination or imaging studies such as ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT). Ultrasound-guided fine-needle aspiration cytology (FNAC) was performed in most of the patients with positive imaging findings to confirm lymph node metastasis before surgery.
All robot-assisted procedures were performed by the same surgeon (KT). The patients were informed about the robot-assisted operative procedure and the possibility of conversion to conventional open surgery, and written informed consent was obtained from all patients. The study was approved by the institutional review board.
Surgical procedure of robot-assisted modified radical neck dissection
Elevation of the skin flap and dissection of levels II, III, and VA
Levels II, III, and VA were dissected with conventional instruments under direct vision. With the patient in the supine position, the neck was extended slightly without shoulder roll and the head was turned to the side opposite the lesion. A post-auricular facelift incision was designed in the post-auricular sulcus and along the occipital hairline without extension to the pre-auricular area ( Fig. 1 ). The skin flap was elevated in the subcutaneous plane in the post-auricular area and continued anteriorly in the plane of the subplatysma level over the sternocleidomastoid (SCM) muscle after identification of the lateral margin of the platysma muscle under direct vision. The extent of skin flap elevation was anteriorly to the midline of the neck, inferiorly to the clavicle, superiorly to the lower border of the mandible, and posteriorly to the anterior border of the trapezius muscle ( Fig. 2 ). Good visualization with illumination is essential for elevating the skin flap, and an illuminated long-blade retractor such as a retractor used for breast surgery is useful for good visualization and access to the deep portion of the skin flap.
