Smith et al.: Transoral Robotic Total Laryngectomy

Transcription

1 The Laryngoscope VC 2013 The American Laryngological, Rhinological and Otological Society, Inc. Transoral Robotic Total Laryngectomy Richard V. Smith, MD; Bradley A. Schiff, MD; Catherine Sarta, RN; Stephane Hans, MD, PhD; Daniel Brasnu, MD Objectives/Hypothesis: Minimally invasive surgery has become the standard of care in many organ systems. Head and neck surgery has incorporated transoral surgery, either laser microsurgery or robotic resection, in the management of pharyngeal and laryngeal cancers. To date, the laryngeal procedures have taken the form of partial laryngectomy, as transoral approaches have not allowed reconstruction following total laryngectomy. We present the first series of transoral total laryngectomies. Study Design: Multinational, multi-institutional prospective consecutive case series. Methods: Case series of completed and attempted transoral robotic surgery (TORS) total laryngectomy performed under an institutional review board protocol. The procedure was developed in the cadaver laboratory and applied to selected individuals requiring total laryngectomy for recurrent laryngeal cancer or post-therapeutic organ dysfunction. Results: TORS total laryngectomy was successfully performed in five patients and was unsuccessful in two others. Two of the patients had postoperative fistulae, and all seven are without evidence of recurrent cancer and are swallowing orally without gastrostomy supplementation. Conclusions: TORS total laryngectomy is feasible and can be taught to other surgeons. Potential benefits of this approach are present for patients undergoing salvage laryngectomy and include improved wound healing and functional results. This procedure further extends the applications of robotic head and neck surgery. Key Words: Total laryngectomy, endoscopic, surgery, transoral robotic surgery. Level of Evidence: 4. Laryngoscope, 123: , 2013 INTRODUCTION The treatment of advanced larynx cancer has undergone a considerable evolution over the past 20 years. This change, however, has been primarily in the nonsurgical realm, as total laryngectomy has remained unchanged for more than 100 years. Before 1991, patients with advanced larynx cancer were usually treated with total laryngectomy and adjuvant radiation therapy as dictated by the stage and pathologic findings. The Veterans Administration (VA) laryngeal cancer study, published in 1991, 1 compared patients treated with induction chemotherapy and radiation therapy with patients treated with total laryngectomy and adjuvant therapy. Patients in the nonsurgical arm showed no decrease in survival and increased laryngeal preservation, leading to the adoption of nonsurgical therapy of patients requiring primary total laryngectomy. The From the Department of Otorhinolaryngology Head and Neck Surgery (R.V.S., B.A.S., C.S.), Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, U.S.A; and Hopital Europeen Georges Pompidou (S.H., D.B.), AP-HP, University Paris Descartes, Paris, France. Editor s Note: This Manuscript was accepted for publication October 1, Additional Supporting Information may be found in the online version of this article. The authors have no funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Richard V. Smith, MD, FACS, Professor and Vice-hair, Department of Otorhinolaryngology Head and Neck Surgery, Montefiore Medical Center, 3400 Bainbridge Avenue, Bronx, NY rsmith@montefiore.org DOI: /lary RTOG study, 2 the follow-up to the VA study, was a three-arm randomized trial comparing radiotherapy alone versus sequential chemotherapy and radiotherapy versus concurrent chemotherapy, completely eliminating primary total laryngectomy for the treatment of advanced laryngeal cancer. This study has supported the routine use of concurrent chemotherapy and radiation therapy as a first line treatment for many advanced laryngeal cancers 3 and has led many to abandon primary total laryngectomy. The increased use of chemotherapy and radiation therapy for the primary treatment of advanced larynx cancer has led to salvage surgery performed in a hostile tissue field exposed to the effects of chemotherapy and high-dose radiation therapy. Patients undergoing primary chemotherapy and radiation therapy will, nearly always, require total laryngectomy for salvage 4 and be subjected to increased postoperative complications. 5 A study by Ganly et al. showed a statistically significant increase in pharyngocutaneous fistula when comparing salvage laryngectomy in patients who had received chemotherapy and radiation therapy (32%) to those receiving primary laryngectomy (12%). 6 This finding has led to the recommendation of flap coverage of total laryngectomy repairs in patients undergoing salvage surgery following chemotherapy and/or radiotherapy. 7,8 Therefore, salvage laryngectomy is a more complex procedure than primary laryngectomy and often requires significantly more resources. Coincident with the shift toward nonsurgical treatment of patients with advanced larynx cancer are the considerable advances in surgical options for early, and

2 select advanced, laryngeal cancers. Transoral laser microsurgery (TLM) of early larynx cancer, as pioneered by Strong and Jako in America 9 and popularized in Europe, showed outstanding results and offered decreased morbidity when compared to open procedures. Although laryngeal cancer surgery was at the forefront of TLM for head and neck cancer, transoral surgery has become more frequently employed in other head and neck sites, such as the oropharynx. Transoral robotic surgery (TORS), utilizing the DaVinci robotic surgery system (Intuitive, Sunnyvale, CA) has begun to play a larger role in the surgery of the upper aerodigestive tract. TORS has proven to be safe, feasible, and minimally invasive 10,11 within the oropharynx and has also proven feasible for sites outside of the oropharynx, including the supraglottic larynx and base of skull The use of TORS can extend the indications of transoral surgery through improved visualization and intrapharyngeal suturing, among other advantages. This has allowed the development of complex transoral procedures, and we present the first series of transoral robotic total laryngectomy. The goals of this study were to assess the safety and efficacy of this technique, as well as to verify that the technique was not operator specific. MATERIALS AND METHODS The procedure was developed in a cadaver model, using the DaVinci Surgical System (Intuitive Surgical Inc., Sunnyvale, CA). TORS is being evaluated on an institutional review board approved protocol assessing safety, efficacy, and quality of life in patients with select pharyngeal and laryngeal cancers. The first total laryngectomy was performed at the Montefiore Medical Center in July of The technique was then taught to collaborators in Paris, who have also performed the procedure. Six of the seven patients selected for this procedure had received prior chemotherapy and/or radiation therapy and required a total laryngectomy to manage their recurrence or treatment sequelae. The other patient required a total laryngectomy to manage organ dysfunction and chronic aspiration following long-term intubation and multiple surgical failures. Technique The procedure begins with a transcutaneous approach to the trachea to secure the airway. After the patient is given intravenous sedation, the stomal incision is outlined between the cricoid cartilage and suprasternal notch, and the subcutaneous and paratracheal tissues are infiltrated with 1% lidocaine/ 1:100,000 epinephrine local anesthetic. The skin of the stomal site is excised, and dissection of the pretracheal tissue is completed with division of the thyroid isthmus. The anterior trachea is exposed from the cricoid to the fourth tracheal ring, and the trachea is entered between the second and third rings. An anode endotracheal tube is placed and general endotracheal anesthesia initiated, after which paratracheal dissection, either uni- or bilateral, is completed through the stomal opening as indicated. Hemi- or total thyroidectomy may also be performed through this incision if required. The posterior wall of the trachea is then incised and the posterior tissues are mobilized superiorly, separating the remaining superior trachea from the esophagus. The anterior half of the trachea is then matured to the inferior stomal incision, and the remainder of the procedure, with the exception of closing the superior half of the stoma and insertion of a closed suction drain, is completed transorally. Fig. 1. Lateral view of the robot docked with the arms positioned in the oral cavity and the Feyh-Kastenbauer retractor in place. The bed is appropriately positioned with the foot of the bed toward the anesthesia cart. The Feyh-Kastenbauer retractor system (Gyrus Medical Inc., Maple Grove, MN) or Crowe- Davis mouth gag is used to expose the pharyngolaryngeal structures and then suspended from the side of the bed with a selfretaining Martin s arm retractor (LTL Medical, Simi Valley, CA). The DaVinci Surgical Robot (Intuitive Surgical Systems) is brought into the field and docked at 30 degrees off the patient s shoulder. The 30-degree telescope is placed into the central arm, and the 5-mm Schertel or Maryland forceps is placed through the left robotic arm and the spatula monopolar cautery into the right. Both arms are advanced into the oral cavity obliquely, with positioning confirmed by the camera. Once all instrumentation is appropriately positioned (Fig. 1), the assistant is positioned at the patient s head to facilitate suctioning, suction cautery, clip application for hemostasis, and transoral retraction, as is standard for all transoral robotic procedures. The resection begins by incising the lateral pharyngoepiglottic fold and anterior vallecula in the standard fashion used for endoscopic supraglottic laryngectomy. This is accomplished bilaterally with hemostatic clip application to the superior laryngeal vascular pedicles. The hyoid bone is dissected free from the pre-epiglottic tissues, maintaining the integrity of the fascial compartment containing the pre-epiglottic fat, and this plane of dissection is continued inferiorly to expose the superior border of the thyroid cartilage. Once identified, the thyroid ala is mobilized posteriorly, leaving the outer thyroid perichondrium intact. The anterior pyriform sinus mucosa is incised, and the lateral pyriform mucosa is mobilized. Transection of the superior laryngeal suspensory ligament facilitates access to the constrictors, which are then dissected. The muscles are then sharply divided, along with the remaining fascia separating the intraoral dissection from the stomal dissection. At this point, the only area preventing removal of the larynx is the postcricoid area. The postcricoid mucosal cut is made under direct transoral visualization, providing appropriate margins for the tumor, and the remainder of the specimen is dissected. The larynx is then fully mobilized and removed transorally (Fig. 2). Closure of the wound is then performed. All surfaces are irrigated and hemostasis is assured, after which the mucosal incision is then closed with several running 3-0 Vicryl sutures. The pharynx is closed primarily with a single horizontal suture line. However, because the integrity of the strap muscles is maintained, if the mucosa was not sufficient to close to itself primarily, the inferior and lateral mucosal surfaces could be closed to the strap muscles in a U-shaped configuration, allowing the central component to heal by secondary intention, as is 679

3 conversion to an open approach. These procedures were both converted after significant cephalad dissection of the larynx, mobilizing the tissue from the hyoid and preepiglottic space down to, and anterior to, the thyroid ala. The dissection field then could not be adequately exposed owing to a narrow pharynx in the lateral dimension and an inability to further deliver the larynx superiorly within the operative field. Two additional patients gave consent for the procedure, but robotic access was limited by three issues: anterior positioning of the larynx with an inability to adequately visualize the vallecula, a narrow mandibular arch preventing placement of the endoscope and robot arms, and poor visualization due to limited retractor options. Fig. 2. Transoral removal of the larynx with the robot moved out of position and the mouth retractor in place. currently the standard for endoscopic resections. The area is again irrigated and inspected from the stoma to confirm a watertight closure. A suction drain is placed through a separate stab incision into the external compartment, and the stomal suturing is completed to finish the procedure. RESULTS The clinical features of the patients are presented in Table I. Each patient presented with a unique set of circumstances and comorbidities. All but one, patient 3, had been treated for cancer before the surgery. Four patients had received chemotherapy and radiotherapy to manage their primary disease, and two had received radiation therapy alone. Five of seven patients (71%) had recurrent cancer, and two had nonfunctional larynges. Patient 3 had a nonfunctional larynx following intubation-related stenosis and chronic aspiration, and patient 6 had severe radionecrosis. Two of these patients had approximately half of the procedure performed robotically, with the inferior portion unable to be completed transorally, requiring DISCUSSION The treatment of larynx cancer has changed greatly in the last 20 years and continues to evolve. The goal of many of the changes has been to decrease morbidity and increase function without decreasing survival. One of the consequences of the use of chemotherapy and radiation as first-line therapy is that salvage surgeries are performed in tissues exposed to the effects of high-dose radiation and chemotherapy. This has been shown to compromise wound healing, leading to an increased incidence of fistula and wound-healing complications, requiring additional surgery, such as flap placement, to minimize fistula development. In addition, the need for routine neck dissection in these patients is not clear, so surgery directed only to the area of primary recurrence, in the absence of clinical or radiographic nodal disease, is a reasonable option. 15 TLM resection techniques have been applied to pharyngeal and laryngeal tumors and have demonstrated comparable rates of tumor control to open and nonsurgical treatments. These procedures have the advantage of being minimally invasive approaches with improved functional outcomes when compared to standard open TABLE I. Patient Demographics and Results. Patient Age, yr Sex Comorbidities Prior Therapy Clinical Stage Pathologic Stage Procedure Institution Complications 1 63 M Liver transplant, cirrhosis 2 38 F HIV, hepatitis C Chemo/RT rt4an0m0 rt4an1m0 TL, level VI, hemithyroid RT rt2n0m0 rt2n0m0 TL, level VI MMC None MMC Fistula failed to close with 2 subsequent open free flaps 3 65 F N/A None N/A N/A TL HEGP Fistula healed in 3 wk 4 67 M N/A Chemo/RT rt3n0m0 rt3n0m0 TL HEGP None 5 79 M N/A RT rt2n0m0 rt3n0m0 TL, level VI MMC Inadequate exposure 6 58 M ORN larynx Chemo/RT N/A N/A TL MMC Inadequate exposure 7 63 M N/A Chemo/RT rt3n0m0 rt4an0m0 TL MMC None All patients were alive and without evidence of disease at the end of the study. Chemo/RT ¼ chemotherapy and radiotherapy; F ¼ female; HEGP ¼ Hopital Europeen Georges Pompidou; HIV¼ human immunodeficiency virus; level VI ¼ central compartment neck dissection; M ¼ male; MMC ¼ Montefiore Medical Center; N/A ¼ not applicable; ORN ¼ osteoradionecrosis; RT ¼ radiotherapy; TL ¼ total laryngectomy. 680

4 surgery. TLM has limitations in its application to advanced laryngeal tumors, owing to access issues (from line of site surgery) and the inability to suture tissues closed. In addition, surgical manipulation of the tissues is limited, as one hand is used for retraction and the other for manipulation of the laser. Despite these limitations, the techniques have proven successful, particularly for laryngeal cancer. Peretti et al. reported their TLM experience in 595 patients with Tis to T3 glottic carcinoma and had a 5-year disease-specific survival of 100% with a laryngeal preservation rate of 72.7% in their T3 patients. 16 An important component of surgery is the complete resection of the cancer and the achievement of negative margins. This has been shown for many years in open procedures and has been demonstrated by Karatzanis et al. in TLM approaches to laryngeal cancer as well; they report a significant decline in survival, just under 50%, if negative margins are not obtained. 17 Therefore, techniques to enhance exposure and provide adequate margins would be expected to result in improved survival. The application of robotic surgery to head and neck tumors has extended the indications of transoral surgery. TORS has improved visualization and access compared with TLM procedures. The binocular distal telescopic vision, both 0 and 30 degrees, greatly enhances visualization of all structures within the pharynx and larynx, providing a magnified HD (high-definition) three-dimensional picture of the structures. In addition, when compared to TLM, the instrumentation articulates at the distal end of the robotic arm, providing complete freedom of motion with scissors, clamps, and cautery. These characteristics allow a greater degree of tissue manipulation and dissection at perpendicular planes, as opposed to line of site. An additional benefit is obtained with the presence of an assistant at the head of the patient who can simultaneously manipulate the tissues, facilitate hemostasis, and provide suction, among other functions. In effect, the assistant provides an additional pair of hands to perform the procedure. Although it has not been reported, such improved visualization and tissue control may result in improved marginal control. Several authors have demonstrated the safety and efficacy of TORS. Although the patient data are limited for TORS, the principle of transoral resection has been validated using TLM techniques in large series, particularly for larynx cancer. The majority of the series have reported on TORS to manage oropharyngeal primaries, although some have reported supraglottic laryngectomy and hypopharyngectomy. 10,18 21 All have reported excellent rates of margin control, excellent functional recovery, and very low complication rates. These series serve to validate the TORS approach, although the oncologic results are preliminary. Unlike the TORS studies cited, the current series of total laryngectomy patients is using TORS in a salvage setting. Open total laryngectomy in this setting has a high incidence of perioperative complications, including fistula formation. We demonstrate the feasibility of this technique and, in this very limited experience, standard oncologic results. As has been the case with the shift to minimally invasive surgery, TORS total laryngectomy may provide improved healing with a decreased need for routine flap use in salvage laryngectomy patients, although a larger series would be needed to confirm this hypothesis. Although two of our patients had fistulas, one healed rapidly with wound care and the other had severely compromised wound healing, requiring two separate free-tissue transfers (each of which broke down), which likely would have led to pharyngocutaneous fistula formation following an open total laryngectomy as well. The fistulas that occurred in two patients were early in our experience and were, in part, related to technical issues of the dissection. Strict adherence to patient selection, including issues such as anatomy, medical condition, and adjuvant surgical procedures (i.e., low tracheotomy placement), has facilitated the success of the procedure. Particular note should be made of the low tracheotomy, as two of the patients (2 and 7) had unrecognized low tracheotomies placed by other surgeons before referral. Because the tracheotomy site must be removed with the specimen for oncologic reasons, this must be recognized. Significant distal access is very difficult transorally owing to limitations of the robotic arms, both with respect to length and arm conflict outside the mouth. The functional results in these patients were excellent, despite significant resection, without the need for flap reconstruction, with no incidence of pharyngeal or stomal stenosis. All patients were swallowing orally and remained without evidence of disease. The exact indications and limitations of this procedure are not yet defined. As can be seen by the limitation in performing this procedure in two of the seven patients, transoral access remains a limitation. Patients with a narrow mandibular arch, anteriorly displaced larynges, or intact dentition will be poor candidates for TORS total laryngectomy using the current instrumentation and mouth retractors. The two patients who could not receive TORS total laryngectomy had the superior portion of the procedure completed, but we were unable to expose the distal aspect of the larynx owing to anterior positioning of the larynx and a narrow pharynx precluding adequate visualization inferiorly and laterally. This type of access limitation cannot always be determined preoperatively, unlike the narrow mandibular arch and complete dentition, which can predict an inability to expose the patient for robot docking. The characteristics of the oral cavity and mandible, as well as the spatial relationships of the pharynx and larynx, should be carefully assessed at the time of the diagnostic tumor endoscopy. Also, consent for open conversion of the procedure must be obtained before starting a transoral resection. The technical considerations of this procedure are critical to its successful outcome. There are several points at which the procedure may be compromised. Adequate visualization of the vallecula and aryepiglottic folds must be present at the onset of the procedure to allow the anterior and lateral exposure required for successful progression of the surgery. Without adequate visualization, the distal lateral cuts will not be possible. If the perihyoid tissues have not been involved with the 681

5 cancer, either in the primary or the recurrence, the hyoid bone should be left in place, dissecting the preepiglottic space in its entirely and keeping the enveloping fascia intact. This will enhance the diameter of the pharyngeal field during dissection, functionally stenting it open during the procedure. Once the dissection proceeds into the pyriform sinus, the suspensory attachments at the superior cornu of the thyroid ala must be transected to allow rotation and delivery of the larynx. This step is critical and is undertaken in conjunction with the division of the middle and inferior constrictors from the thyroid ala. Once this step had been performed, the strap muscles must be carefully dissected from the oblique line of the thyroid cartilage to stay in the appropriate plane and complete the anterior inferior dissection. Such maneuvers may be technically difficult, and this procedure, at this time, is best suited for those with significant transoral resection experience, either with or without the robot. At this time, given the limited experience with the procedure, we feel it is best used in the salvage setting when there is no need to perform concomitant neck dissections, such as with glottic recurrences. The benefit of TORS total laryngectomy, at this time, is in the minimally invasive approach, and the need for an extensive lateral neck dissection may obviate that benefit and complicate the healing. By using this technique, a tailored resection of appropriate mucosa and underlying structures is performed, while maximizing the preservation of vascular and neurologic supply to the pharynx and surrounding musculature. This should translate to improved pharyngeal function when compared to standard total laryngectomy with flap reconstruction. However, that is a theoretical advantage warranting further study. In addition, because the enveloping fascia of the strap muscles remains intact, one could close the mucosa to the strap muscles and allow the remainder to heal with secondary intention, as is the case in TLM and TORS used for pharyngectomy and supraglottic laryngectomy. Should the strap muscles be invaded with tumor, this type of secondary intention healing would not be possible. However, free-flap placement may be achieved through TORS as well 22 and could manage a more significant open wound. Adjuvant procedures, such as thyroidectomy and paratracheal dissection, can easily be performed through the stomal incision at the onset of the procedure, allowing appropriate oncologic management of the central compartment. CONCLUSION TORS total laryngectomy is feasible and reproducible across centers and surgeons. It is clear that this evolution in total laryngectomy remains in its infancy, and the exact indications and patient selection remain unclear. We believe this is an excellent procedure for salvage total laryngectomy in patients with limited glottic disease, respecting the confines of the thyroid cartilage, or those requiring laryngectomy for functional compromise without recurrence. As experience grows, this technique may be appropriate for primary surgery as 682 well, although that would certainly only be the case for a very select group of tumors confined to the larynx. Acknowledgment We acknowledge the assistance of the following individuals: Richard V. Smith for research design, procedure design, and manuscript preparation and editing; Bradley A. 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