Comparison of TORS with Conventional Surgery for Oropharyngeal Carcinomas in T1-T4 Lesions.

OBJECTIVES: Transoral Robotic Simulation (TORS) is an innovative surgical technique indicated for resection of selected head-and-neck cancers. The authors conducted a systematic review discussing the indications, advantages, and disadvantages of this technique. DATA SOURCES: The search included MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, COCHRANE, and bibliographies of relevant studies through January 2006.
MATERIALS AND METHODS: Studies included patients treated for T1-T4 stage oropharynx cancer with TORS. Study retrieval and data extraction were conducted in duplicate and resolved by consensus. Treatment specific details, as well as recurrence, survival, and adverse events, were collected. Methodological quality for each study was appraised.
RESULTS: Nine studies were included which met the inclusion criteria. Patients receiving TORS required adjuvant radiotherapy (26%) or chemoradiotherapy (41%). Two-year overall survival estimates ranged from 82% to 94% for TORS.
CONCLUSION: The minimally invasive transoral robotic simulation (TORS) for the treatment of oropharyngeal cancers is proved to be less time-consuming, compliant to the patients, and having less complications as compared to the more invasive techniques involving conventional surgery although the quality of this evidence is limited. Copyright:

INTRODUCTION

Advances in the basic scientific research within the field of computer-assisted oral and maxillofacial surgery have enabled the doctors to introduce features of these techniques into routine clinical practice.

Head-and-neck cancers are emerging as a major public health problem in India with over 200,000 new cases every year,[1] reported to have the highest incidence of oropharyngeal cancer worldwide.[2] Carcinomas of the oropharyngeal region show the worst prognosis among all patients with head-and-neck cancer.

The main methods to treat neoplasms of the oropharyngeal region are surgery, radiotherapy, and chemotherapy. Radiotherapy has multiple side effects such as xerostomia and dysphagia and can induce complications, namely trismus and osteoradionecrosis. Hence, the interest in transoral surgical techniques is arising so as to reduce operation-related morbidity and improve the patient's quality of life (QOL).

The idea of “telepresence” or “robotic” surgery was proposed by NASA in 1972 to provide remote surgical treatment to the orbiting astronauts.[34]

The first preclinical tests with robots in the head-and-neck surgery were performed by Kavanagh with the use of “Robodoc” system in 1994.[5]

In head-and-neck surgery, minimally invasive procedures are usually avoided because of concerns about visualization, possible damage to vital structures, and the limited availability of effective instrumentation,[6] but all efforts to decrease the trauma of such operations have recently led to the introduction of robotic surgery.

Recently, transoral robotic surgery (TORS) using the da Vinci robotic system (Intuitive Surgical Inc., Sunnyvale, CA, USA) has been introduced to overcome these limitations of conventional minimally invasive surgical procedures.

Robotics may provide advantages in surgery, including precision, articulation beyond the manipulation achieved by human hand, and three-dimensional (3D) magnification. Robotic surgery has emerged beneficial in terms of reduced blood loss and fewer complications compared to conventional surgery.[78]

More than twenty studies on TORS in animals, cadavers, human subjects, and various head-and-neck cancer sites have been published since 2005.[91011]

Many studies have proved the efficacy, safety, and reduced morbidity of TORS for the removal of T1–T3 or T4 squamous cell carcinomas of the oral cavity, oropharynx, larynx, and hypopharynx.[12131415]

The TORS in all of the studies was carried out with the da Vinci robot. Whereas, the conventional surgical interventions included conventional transoral oropharyngectomy, transmandibular buccopharyngectomy, partial pharyngolaryngectomy, or supraglottic laryngectomy by cervicotomy.

However, no such studies, so far, are found on the comparison of robotic surgery with the conventional minimally invasive surgery for oropharyngeal carcinoma T1–T4 lesions based on the oncological and functional outcomes. Hence, the objective of this systematic review is to compare the effectiveness of TORS with conventional surgical procedures.

MATERIALS AND METHODS

Focused question

What is the efficacy of transoral robotic surgery (TORS) as compared to conventional surgical procedure for the surgery of oropharyngeal carcinoma in T1–T4 lesions?

Eligibility criteria

The inclusion criteria were all articles in English or those having detailed summary in English. Studies published between January 1, 2006 and November 31, 2016. Randomized controlled trials, clinical papers, and series with essential data on TORS for oropharyngeal cancer were included. Studies on patients of known diagnosis of oropharyngeal squamous cell carcinomas of T1–T4 lesions by biopsy and indicated for surgical treatment and patients of at least 18 years of age at the time of diagnosis were selected.

The exclusion criteria were contraindications for general anesthesia or surgery because of a medical condition, cases in which a tumor fixed to lateral oropharyngeal wall, unresectable nodal disease such as carotid artery invasion, and reviews, abstracts, editorials, letters, and historical reviews and in vitro studies.

Search strategy

Two Internet sources of evidence were used in the search of appropriate papers satisfying the study purpose: the National Library of Medicine (MEDLINE and PubMed) and the Cochrane Central Register of Controlled Trials, Google Scholar and manual search using Dr. D.Y. Patil University College library resources. All cross-reference lists of the selected studies were screened for additional papers that could meet the eligibility criteria of the study. The databases were searched up to and including December 2016 using the search strategy [Figure 1].

Figure 1

PRISMA flowchart

RESULTS

Nine studies were included which met the inclusion criteria. Patients receiving TORS required adjuvant radiotherapy (26%) or chemoradiotherapy (41%). Two-year overall survival estimates ranged from 82% to 94% for TORS. Adverse events after Conventional Surgery included esophageal stenosis (4.8%), osteoradionecrosis (2.6%), and gastrostomy tubes (43%) and adverse events for TORS included hemorrhage (2.4%), fistula (2.5%), and gastrostomy tubes at the time of surgery (1.4%) or during adjuvant treatment (30%). Tracheostomy tubes were needed in 12% of patients at the time of surgery, but most were decannulated prior to discharge [Table 1].

Table 1

Data extraction

Study ID	Author & year of publication	Location	Study design	No. of patients	Primary site/diagnosis	Intervention	Advantages	Complication	Conclusion
1	Bert W.O’Malley et al. 2006	Philadelphia , USA	Case series	3	2 patients with T2 and 1 patient with T1 squamous cell carcinoma	TORS		No significant complications	TORS demonstrate technical feasibility of accessing and performing tongue base resections without requiring transcervical or transmandibular approaches.
2	Weinstein G et al. 2010	Philadelphia, USA	prospective cohort study	47	13 patients with T1, 23 patients with T2, 9 patients with T3 and 2 patients with T4 SCC	TORS		2 PEG related complications, 1 pneumonia, 2 alcohol withdrawals and 1 seizure.	TORS offers disease control, survival and safety commensurate with standard treatments and beneficial outcome of gastrostomy dependency rates.
3	Hans S et al., 2007	Paris, France	prospective non-randomised study	23	10 patients with T1, 11 patients with T2 and 2 patients with T3 SCC	TORS	TORS decreases tracheostomy rate, allows faster oral swallowing recovery and shorter hospital stay.	1 intraoperative complication of sudden bleeding occurred.	TORS proves beneficial for early tumors and selected advanced tumors (T3, T4a) of oropharynx, larynx and hypopharynx.
4	K. Aubry et al. 2011	Limoges, France	Case series	17	5 patients with T1 , 9 patients with T2 and 3 patient with T3 SCC	TORS	Low morbidity and improved functional recovery	1 intraoperative complication of pharyngocervical communication.	TORS is a useful surgical alternative to conventional open surgery in selected indications.
5	Leonhardt FD et al., 2011	Pennsylvania, USA	Case series	38	12 patients with T1, 21 patients with T2, 3 patients with T3 and 2 patients with T4	TORS	excellent 3-dimensional visualisation and magnification, tremor filtration, motion scaling that facilitate delicate dissection		Use of TORS alone had minimal and temporary effects on speech and TORS plus radiation has significantly fewer detrimental effects on QOL than when combination chemoradiation was used.
6	Lallemant B et al., 2013	France	retrospective study	23	16 patients with T1 and 7 patients with T2	TORS		2 cases if postop comolications, one developed cervical surgical emphysema and pneumothorax and other bled from right superior laryngeal artery.	For some pts who are impossible to treat using a conventional CO2 laser approach, laryngeal TORS may enable transoral surgical tumor resection
7	Lee SY et al. , 2013	Korea	prospective non-randomised study	57	16 patients with T1, 32 patients with T2 and 9 patients with T3.	TORS and Conventional surgery (Transoral and Mandibulotomy approach)	TORS group had a shorter operation time, more rapid recovery of swallowing and shorter hospital stay than Conventional group	In mandibulotomy group, flap failure occurred in 1 patient, Malunion and osteoradionecrosis occurred in 2 patients resp.	TORS seems to have distinct advantages over conventional transoral surgery but further studies are needed.
8	Hammoudi K et al., 2014	France	Retrospective study	26	3 patients with T1, 19 patients with T2 and 4 paients with T3 tumors	TORS AND Conventional surgery (transoral oropharyngectomy, TMBP, Oropharyngectomy by cercicotomy and supraglotic pharyngotectomy by cervicotomy)	TORS group had a shorter duration of primary tumor resection and neck dissection, shorter hospital stay and shorter duration of NG tube feeding	Not significant	TORS might result in lower morbidity and treatment costs for selected head and neck squamous cell carcinomas.
9	Wang C et al., 2015	Taiwan	Retrospective study	10	5 patients with T1 and 5 patients with T2	0	Patients receiving TORS had no recurrence, shorter tube feeding and almost no need of tracheostomy	None	TORS is a feasible transoral appraoch for selected patients with early T classification hypopharyngeal cancer.
10	Lorincz B et al., 2015	Germany	Case series	50	24 patients with T1, 23 patients with T2, 2 patients with T3 and 1 patient with T4.	TORS	Reduced surgical morbidity and good margin control		TORS shows a shortened treatment course, decreased costs, faster revocery and preserved chemo- and radio-therapy options for potential recurrences or second primary tumors in future
11	Dabas S et al., 2015	New Delhi, India	Case series	60	17 patients with T1, 19 patients with T2, 4 patients with T3.	TORS	no long term PEG tube dependency in pts undergoing TORS	postop bleeding in 5 patients of which 3 required operative intervention. 1 died due to secondary hemorrhage.	TORS represents a new innovative minimally invasive approach in the treatment of oropharyngeal cancers which is safe, feasible and effective alternative to open surgical treatments

DISCUSSION

The primary goal of head-and-neck cancer treatment is local control and organ preservation. Historically, surgical excision followed by adjuvant therapy in the form of Chemotherapy Radiotherapy (CTRT) was the treatment of choice for most oropharyngeal cancers. Hence, in the recent past, transoral robotic simulation (TORS) has gained tremendous popularity proving to be more efficient for treating oropharyngeal carcinomas.

The implementation of new surgical technology requires rigorous study of the comparative effectiveness with the existing treatment modalities. Although several randomized trials are done till date, there have been no studies measuring the comparative effectiveness of TORS with conventional surgery for oropharyngeal carcinomas. In the present study, we systematically reviewed the literature for case series that reported outcomes pertaining to advantages and limitations of the same. Due to the heterogeneity of existing studies and lack of comparator arms, meta-analysis could not be performed.

In a study conducted by O’Malley et al.[16] in 2006, they used TORS on three human subjects with base of tongue neoplasms with the objective of developing a minimally invasive surgical technique for treating such lesions. Using the da Vinci surgical robot, a total of ten base of tongue resections were performed on edentulous and dentate cadavers as well as live mongrel dogs. They concluded that TORS provided excellent 3D visualization and instrument access that allowed successful surgical resections from cadaver models to human patients. TORS demonstrated the technical feasibility of accessing and performing tongue base resections without requiring transcervical or transmandibular approaches.

Weinstein et al.[15] in 2010 conducted a prospective cohort study on 47 adult patients with newly diagnosed and previously untreated oropharyngeal carcinoma with an objective to determine the oncologic and functional outcomes in patients undergoing TORS, followed by adjuvant therapy with a follow-up period of 18 months. The group of patients was divided into T1, T2, T3, and T4. The complications included were two percutaneous endoscopic gastrostomy (PEG)-related complications, one pneumonia, two alcohol withdrawals, and one seizure. They came to a conclusion that TORS offers disease control, survival and safety commensurate with standard treatments, and beneficial outcome of gastrostomy dependency rates.

A prospective study was conducted by Hans et al.[17] in 2011 in Paris, France, on 23 patients with T1, T2, and T3 lesions. They evaluated the feasibility of TORS, robotic setup time, transoral robotic surgery time, blood loss, surgical margins, tracheotomy, feeding tube, time to oral feeding, and surgery-related complications. They concluded that TORS decreases the tracheostomy rate and allows faster oral swallowing recovery and shorter hospital stay. One intraoperative complication of sudden bleeding occurred. They concluded that TORS proves beneficial for early tumors and selected advanced tumors (T3 and T4a) of the oropharynx, larynx, and hypopharynx.

Aubry et al.[18] conducted a case series report on 17 patients with T1, T2, and T3 lesions, in which they discussed the indications, advantages, and disadvantages of TORS for head-and-neck cancer. The advantages of TORS include low morbidity and improved functional recovery. They reported one intraoperative complication of pharyngocervical communication. They concluded that TORS is a useful surgical alternative to conventional open surgery in selected indications. They further stated that studies on QOL, speech rehab, swallowing, and long-term oncological results will be essential in order to objectively compare TORS with other surgical and nonsurgical treatments.

Leonhardt et al.[19] in 2011 conducted a study on 38 patients with T1, T2, T3, and T4 lesions. The aim of this study was to assess the QOL and function of patients with squamous cell carcinoma of the oropharynx after 1 year of TORS. According to their experience, TORS provided advantages of excellent 3D visualization and magnification, tremor filtration, and motion scaling which facilitate delicate dissection. They concluded that the use of TORS alone had minimal and temporary effects on speech and TORS plus radiation has significantly fewer detrimental effects on QOL than when combination chemoradiation was used.

A retrospective study on 23 patients with T1 or T2 laryngeal squamous cell carcinoma was conducted by Lallemant et al.[20] in 2013 in France with the objective of determining the feasibility and preliminary oncological results of TORS for the treatment of early-stage laryngeal tumors. Two cases developed postoperative complications: one developed cervical surgical emphysema and pneumothorax and other bled from the right superior laryngeal artery. Their study demonstrated that laryngeal TORS is feasible. For some patients who are impossible to treat using a conventional CO2 laser approach, laryngeal TORS may enable transoral surgical tumor resection.

Lee et al.[21] conducted a prospective study on 57 patients with tonsillar cancer, in which 27 patients underwent TORS and 30 patients were operated by conventional surgery through a transoral approach or mandibulotomy approach. The outcomes they measured were to assess voice status at postoperative 12 months and swallowing function at postoperative 12 months. They found that the TORS group had a shorter operation time, more rapid recovery of swallowing, and shorter hospital stay than the conventional group. The TORS group showed no significant complications, whereas in the mandibulotomy group, flap failure occurred in one patient and malunion and osteoradionecrosis occurred in two patients. Hence, they concluded that TORS seems to have distinct advantages over conventional transoral surgery, but further studies are needed.

A retrospective study was conducted by Hammoudi et al.[22] in 2014 in France on 26 patients with squamous cell carcinoma of the upper aerodigestive tract to compare the functional and oncological results and treatment costs of TORS and conventional surgery for squamous cell carcinoma in the matched group of patients. The conventional surgical interventions used included transoral oropharyngectomy, transmandibular buccopharyngectomy, partial pharyngolaryngectomy, or supraglottic laryngectomy by cervicotomy. They studied the postoperative parameters of duration of tracheotomy, feeding by nasogastric tube, hospitalization in days, and complications. They concluded that robotic technique results in lower morbidity and treatment costs for selected head-and-neck squamous cell carcinomas, with no increase in complication rate and equivalent oncologic control.

Dabas et al.[23] from New Delhi in 2015 conducted a case series on sixty patients with oropharyngeal carcinomas operated by TORS to assess the advantages of the same. They noticed no long-term PEG tube dependency in patients undergoing TORS. The complications included postoperative bleeding in five patients, of which three required operative intervention. One died due to secondary hemorrhage. They concluded that TORS represents a new innovative minimally invasive approach in the treatment of oropharyngeal cancers which is a safe, feasible, and effective alternative to open surgical treatments.

Limitations

The limitations or shortcomings in our systematic review are due to insufficient data, limited access to the full articles, and lack of expert guidance.

CONCLUSION

The minimally invasive transoral robotic simulation (TORS) for the treatment of oropharyngeal cancers is recently becoming popular due to being less time-consuming, compliant to the patients, and having less complications as compared to the more invasive techniques involving conventional surgery although the quality of this evidence is limited. Hence, we would recommend that more randomised controlled trials in this field should be carried out, so that the implementation of TORS techniques for oropharyngeal carcinomas in the near future is carried out.

Future implications

As very few randomized control trials are performed on this study, we would seek studies with high-quality evidence-based randomized control trials with conclusive objective results in the future.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.