Source: www.cancernetwork.com
Author: Amy Y. Chen, MD, MPH, FACS

This paper by Drs. Bhayani, Holsinger, and Lai describes a new approach to an old problem. Advances in the management of head and neck cancer over the past few decades have been made predominantly in the area of non-surgical therapy. Starting with the Veterans Affairs Cooperative Trial for laryngeal cancer in the early 1990’s,[1] advances in the administration of chemotherapy and radiation therapy have enabled patients to forego traditional extensive resections that compromised speech and swallowing function.[2] The advances in combined chemoradiation for advanced head and neck cancer have come with a detriment to some patients in survival and quality of life.[3] Effective treatment, but with decreased morbidity was needed.

Robotic surgery is one treatment that, in combination with chemotherapy and radiation, as needed, is yielding comparable oncologic outcomes while preserving speech and swallowing function. The authors detail the history of robotic surgery well.

In short, the current daVinci system functions as a master-slave robot, with the surgeon manipulating instruments connected by a cable network to the robotic cart. Three arms exist (one for the camera and two accommodate 8mm and 5mm instruments).

The camera enables not only magnification but also three dimensional viewing of the surgical field. The advantage of using robotic arms is the ability to reach locations that were previously not reachable without a mandibulotomy and/ or pharyngotomy.

Stage III and IV cancers of the head and neck consist of primary tumors of all sizes. The major determinant of advanced stage disease, particularly in oropharynx cancers, is the presence of nodal disease. Small primary tumors of the base of tongue and tonsil with the presence of nodal disease (no matter how extensive or numerous) are classified as at least Stage III, and the papers describing non-surgical therapy for oropharyngeal cancers recommend combined chemotherapy and radiation therapy for these patients. Alternatively, one can resect the primary and the neck disease and then radiate at a lower dose, often 10% lower than definitive treatment dose, 60-63 Gy versus 70 Gy.[4]

Advantages of Robotic Surgery
The main advantages of using trans oral robotic surgery (TORS), particularly for oropharynx cancers, is the ability to preserve swallowing and speech function without compromising oncologic outcomes. Before TORS, the approach to the oropharynx would often require a mandibulotomy and/ or pharyngotomy. The postoperative course of such surgery would require several days hospitalization in addition to a reliance on tube feedings while the oral and oropharyngeal mucosa healed to prevent fistula. Tumors of the larynx can also be resected with TORS, especially since better visualization of the anterior commissure and ventricle can be achieved with TORS. TORS enables excellent visualization and the ability to manipulate and resect tumors because of the six degrees of freedom offered by the robotic arms and by the camera. After achieving resection with negative margins, any adjuvant treatment (most commonly, radiation) can be administered at a lower dose.[4] In addition, most patients do not need a tracheotomy or an extended hospitalization. The second advantage is that of preserving speech and swallowing.[5, 6] Even if the patient is to require adjuvant therapy, the toxicity from the lower dose of radiation and oftentimes without concurrent chemoradiation is significantly less and results in better functional outcomes.

Disadvantages of Robotic Surgery
The authors describe the costs of acquiring the daVinci robot as well as the increased in required set-up time The costs are certainly one concern and a potential disadvantage. The cost of one daVinci robot is in excess of several hundred thousand dollars; however, as the author notes, if multiple specialties utilize the instrument, the acquisition costs can be better justified. The increased set-up time was documented to decrease once the surgical staff became more facile with the equipment and set-up.

Another potential disadvantage is that the allure of this new approach to head and neck cancer may attract surgeons who do not have specialty training in head and neck oncologic surgery. Robotic prostatectomy has certainly grown mostly due to market driven forces.[7] The pitfall of such market-driven health care is the potential for adverse outcomes to decrease the positive results of the surgery when less-experienced surgeons perform oncologic resections simply because TORS is a new and marketable procedure. Thus, a thoughtful and careful process for disseminating training and credentialing of individuals will be imperative.

Summary
Achieving optimal oncologic outcomes is always the priority for care of our head and neck cancer patients. Preserving functional status is equally important. Traditional surgical approaches to the oropharynx were extensive and unappealing to patients. This led to a surge in the use of chemoradiation for these patients[8,9]. However, these nonsurgical treatments often left the patients with long-term gastrostomy tubes and tracheotomies, and thus they did not achieve the goal of preserving functional status. TORS is a new approach to tried and true oncologic resections and has demonstrated comparable to improved oncologic and functional outcomes. Adding TORS to the multidisciplinary care of head and neck cancer patients, particularly those with oropharynx and larynx primaries, may allow our patients to achieve a cancer-free and highly functional life.

Author’s affiliation:
Associate Professor, Department of Otolaryngology-Head and Neck Surgery, Emory University School of Medicine

References:
1. Department of Veterans Affairs Laryngeal Cancer Study Group. Induction chemotherapy plus radiation compared with surgery plus radiation in patients with advanced laryngeal cancer: the Department of Veterans Affairs Laryngeal Cancer Study Group. New England J of Med 1991; 324(4):1685-90.
2. Machtay M, Moughan J, Trotti A, et al. Factors associated with severe late toxicity after concurrent chemoradiation for locally advanced head and neck cancer: an RTOG analysis. J Clin Oncol 2008; 26(21):3582-9.
3. Chen AY, Halpern M. Factors predictive of survival in advanced laryngeal cancer. Archives of Otolaryngology-Head Neck Surg 2007; 133(12):1270-1276.
4. Weinstein GS, Quon H, O’Malley BW Jr, et al. Selective neck dissection and deintensified postoperative radiation and chemotherapy for oropharyngeal cancer: a subset analysis of the University of Pennsylvania transoral robotic surgery trial. Laryngoscope 2010 Sep; 120(9):1749-55.
5. Genden EM, Desai S, Sung CK. Transoral robotic surgery for the management of head and neck cancer; a preliminary experience. Head Neck 2009; 31(3): 283-9.
6. Iseli TA, Kulbersh BD, Iseli CE, Carroll WR et al. Functional outcomes after transoral robotic surgery for head and neck cancer. Otolaryngol Head Neck Surg 2009; 141(2):166-71.
7. Nickel JC. Seduced by a Robot. Can Urol Assoc J 2009;3(5);359-61.
8. Chen AY, Schrag NM, Hao Y, et al. Changes in treatment of advanced laryngeal cancer 1985-2001. Otolaryngology- Head and Neck Surgery 2006; 135:831-837
9. Chen AY, Schrag NM, Hao Y, et al. Changes in treatment of advanced oropharyngeal cancer 1985-2001. Laryngoscope 2007; 117:16-21