Robotic Thyroidectomy for Thyroid Cancer; Using A Gasless, Transaxillary Approach
Woong Youn Chung
INTRODUCTION
Over the last decade, improved socioeconomic status has increased interest in health and quality of life. This trend has greatly influenced the so-called doctor-patient relationship and treatment planning. Previously, patients’ attitudes to therapy were somewhat passive, and patients usually followed doctors’ recommendations. However, nowadays, patients study their diseases using the Internet or specialty publications and seek advice about their disease statuses and treatment options from various experts. Subsequently, they actively participate in therapeutic decision making with their doctors. Accordingly, many medical and surgical therapies had been modified based on quality of life associated factors, such as postoperative pain, morbidity, length of hospitalization, cosmesis, and return to full activity. In accord with these concepts, minimally invasive surgery has rapidly developed in various surgical fields.
Minimally invasive and endoscopic surgical techniques have only recently been used in the head and neck area, due to the spatial and anatomical limitations imposed by a lack of preexisting working space, the hypervascularities of target organs, and the fact that these organs are surrounded by critical nerves and major vessels.
After the first report was issued on endoscopic thyroidectomy by Hüscher et al. in 1997, various types of minimally invasive and endoscopic surgical techniques were introduced for the thyroid gland. However, endoscopic thyroidectomy had some limitations: (1) the operative view is unstable because surgeons tend to rely on assistants (rotating residents, interns) to hold scopes; (2) it is difficult to perform sharp dissection around the recurrent laryngeal nerve (RLN) or in the Berry’s ligament region with endoscopic instruments; and (3) the straight and relatively unsophisticated design of endoscopic instruments makes it difficult to perform meticulous lymph node dissection in deep, narrow areas or regions with an angled approach.
In the late 20th century, dexterous robotic technology with computer-enhanced, master-slave telemanipulator systems was introduced to the surgical field. The use of surgical robotic systems has enabled surgeons to overcome the above mentioned shortcomings of endoscopic thyroidectomy by providing three-dimensional images in magnified view and allowing greater dexterity and more accurate instrument movements, for example, by hand-tremor filtering, by motion scaling, and by enabling fine movements. Furthermore, the camera and instruments are completely controlled by the surgeon. These advantages are particularly useful when the operative field is deep and narrow and when sharp dissection is needed.
In 2007, the surgical safety and feasibility of robotic thyroid surgery using a gasless, transaxillary approach was first introduced by surgeons in Korea, and since then, many studies have been performed concerning the technical aspects and functional or surgical outcomes of robotic thyroid surgery. Currently, robotic thyroid surgery is viewed as a promising method in the minimally invasive surgical armamentarium for the thyroid gland.
In this chapter, the detailed method of robotic thyroidectomy for the management of well-differentiated thyroid cancer is described.
HISTORY
In 1909, Theodor Kocher won the Novel prize for performing the first successful total thyroidectomy using an aseptic technique, and for a century, conventional open thyroidectomy was considered the safest and most effective method and the standard operative approach to the thyroid gland. However, the conventional open method requires a long skin incision and a wide skin flap in the anterior neck area, which can lead to prominent hypertrophic scars or keloids and discomfort in the anterior neck due to fibrosis and adhesions.
The minimally invasive approach to thyroid surgery was introduced by Gagner et al. in 1996, who issued the first report on endoscopic subtotal parathyroidectomy for secondary hyperparathyroidism. Subsequently, Hüscher et al. reported the successful performance of endoscopic right thyroid lobectomy for a thyroid nodule, and in 1997, Yeung et al., described endoscopic thyroid and parathyroid surgery.
In 1998, Shimizu introduced video-assisted neck surgery using a gasless technique, and in 2000, Ikeda described an axillary approach and Ohgami using a breast approach. To improve cosmetic results, endoscopic thyroidectomies based on various approaching routes have been described, such as cervical (minimally invasive video-assisted thyroidectomy), anterior chest wall, breast, axillary, axillo-bilateral-breast, bilateral axillary, unilateral axillo-breast, and bilateral axillo-breast approach and postauricular and axillary approach. To create working space, continuous CO2 insufflation method and a gasless method using an external retractor have been applied. These various approach routes and methods for sustaining working space have their own advantages and pitfalls, and thus, currently no one technique can be described as better or optimal. Nevertheless, more comfortable, less demanding, and efficient methods are favored and widely used by beginner surgeons.
During the transaxillary approach, which was introduced by Ikeda, the surgeon approaches the lateral aspect of the thyroid, from which he can easily manipulate the superior and inferior poles of the thyroid and identify the parathyroid and RLN. Ikeda used continuous CO2 insufflation to create working space, but when this method is used, the field of view can easily be disturbed by smoke or fumes created during electrical cautery and or by a Harmonic scalpel. To solve these problems, I developed a gasless endoscopic operation method using an external retractor and a transaxillary approach in 2001. The gasless endoscopic method presents no risks of complications, such as hypercapnia, respiratory acidosis, tachycardia, subcutaneous emphysema, or air embolism, and is based on the use of an external retractor which I designed which can be connected to a continuous suction line by a channel in the midline of the retractor blade.
Our operative technique takes advantage of the gasless method and the transaxillary approach. The most remarkable benefits of this method were realized while performing central compartment neck dissection (CCND) on malignant tumors from the carotid artery to substernal notch and prelaryngeal area, including paraesophageal lymph nodes. Other additional benefits of this lateral approach are that the anterior surfaces of the sternoclei-domastoid (SCM) (sternal head) and strap muscle are not dissected, which enables the surgeon to preserve the sensory nerves around the anterior neck area, and thus, to avoid any postoperative hyperesthesia in its region.
Nevertheless, endoscopic surgery has its limitations due to the technical complexities associated with managing nonflexible endoscopic instruments given a two-dimensional (2D), flat operative view. However, the da Vinci surgical robotic system (Intuitive, Inc., Sunnyvale, CA) substantially overcomes the haptic (non-tactile sense), optic (2D representation), and instrumental limitations of conventional endoscopic procedures and facilitates minimally invasive surgery. In 2007, we used the dexterity of this robotic system (the da Vinci S system) to perform the first successful robotic thyroidectomy using a gasless, transaxillary approach in patients with cancer of the thyroid, and since, the technical safety, feasibility, functional benefits, and surgical outcomes of this approach have been serially described.
PHYSICAL EXAMINATION
A complete examination of the head and neck must be performed. The size and mobility of the primary tumor are important. It is also critical to note fixation to the skin or underlying structures since this may be a contrain-dication to this procedure. The identification of the enlarged lymph nodes in the central neck as well as the lateral neck greatly influences the decision making with regard to the extent and type of surgery to be performed.
INDICATIONS
I had performed 650 gasless endoscopic thyroidectomies using a transaxillary approach from 2001 before performing the first robotic thyroidectomy. Based on the feasibility and safety of endoscopic thyroidectomy for papillary thyroid microcarcinoma, initial cases treated by robotic thyroidectomy were limited to well-differentiated thyroid carcinoma (WDTC) with a tumor size of ≤2 cm without definite extrathyroidal tumor invasion (T1 lesion) or to follicular neoplasm with a tumor size of ≤5 cm. Lesions located in the thyroid dorsal area, especially adjacent to the tracheoesophageal groove, were considered ineligible due to the possibility of injuring the trachea, esophagus, or RLN during robotic thyroidectomy. However, as robotic experience accumulated, I was able to manage unexpectedly encountered advanced cases, such as cases with definite
adjacent muscle invasion or multiple nodal metastasis, successfully without open conversion. Currently, the indications for robotic thyroidectomy have been expanded to include patients with T3 or larger size lesions.
adjacent muscle invasion or multiple nodal metastasis, successfully without open conversion. Currently, the indications for robotic thyroidectomy have been expanded to include patients with T3 or larger size lesions.
All patients are preoperatively diagnosed and histologically confirmed by ultrasonography-guided fine-needle aspiration biopsy. Staging neck ultrasonography and neck CT scan can be used to evaluate preoperative clinical stages. The eligibility criteria for robotic thyroidectomy are as follows: (1) WDTC, (2) a primary tumor size of ≤4 cm, and (3) minimal invasion by primary tumor into the anterior thyroid capsule and strap muscle.
CONTRAINDICATIONS
The exclusion criteria that should be applied are (1) definite tumor invasion of an adjacent organ such as the RLN, esophagus, major vessels, or trachea; (2) metastasis to multiple lymph nodes in multilevels of the lateral neck; or (3) perinodal infiltration at a metastatic lymph node.
