For stage I & II oropharyngeal carcinoma, available options are Radiotherapy and surgery. Radiotherapy is associated with significant morbidity which gets more worse with concomitant radiation or chemotherapy use.1 

Robotic surgery is a type of minimally invasive surgery. Minimally invasive means operating on patients through small incisions and use of miniaturised surgical instruments. This advanced technology is now being used in many transoral Head and Neck surgeries, urological, gynaecological, cardiothoracic and general surgical procedures. The patient experiences a number of benefits in surgery performed by Robotic surgery as compared to open surgery which includes minimal scarring, fast recovery time less trauma to the body and less deformities [2,3].

The potential benefits of Transoral Robotic surgery as compared to conventional surgical approaches in the management of head and neck cancers is due to the better visualisation and access to the surgical site [3,4].

Transoral Robotic Surgery (TORS) services commenced in 2016 in the Department of Otolaryngology and Head & Neck Surgery PGIMER, Chandigarh in 2016. The aim of this prospective study is to evaluate the mortality at one year follow-up of patients having early tumors of oropharynx undergoing Transoral Robotic Surgery.    

AIMS AND OBJECTIVES

To evaluate the mortality at one year follow-up of patients having early tumors of oropharynx undergoing Transoral Robotic Surgery.

This prospective study was conducted in patients of T1 & T2 tumours of the oropharynx who were treated by Transoral robotic Surgery between the period August 2016 to October 2018 at the Department of Otolaryngology and Head and Neck surgery, Post Graduate Institute of Medical Education and Research, Chandigarh. An ethical clearance was obtained from the institute Ethical committee. During this period 42 patients were operated by TORS. An informed written consent was obtained in all the cases.

Inclusion Criteria:

• Biopsy proven T1, T2 oropharyngeal squamous cell carcinoma 

• Patients with adequate exposure for TORS 

• No need for local reconstruction

• Age group between 18-75 years

• Patients of both gender

Exclusion Criteria:

• Patients with Trismus

• Previous surgical treatment for head and Neck cancer

• Tumors of advanced T stage

Patients with positive resection margins on post operative histopathological report, extranodal spread and lymph node involvement were referred to radiotherapy.

All patients were preoperatively worked up with detailed History, clinical examination of the Head and Neck, Computerised tomography scan with contrast from base of skull to 4th thoracic vertebra and MRI with Gadolinium to assess the extent of tumour, Fine needle aspiration cytology, X-ray chest PA view and blood routine tests were also performed. Biopsy of the lesion was done and patients with squamous cell carcinoma of oropharynx were recruited.  Pre anaesthetic checkup was done for all patients. The excised lesion was sent for histopathological examination with proper marking by sutures. The specimen was also subjected for Human Papilloma Virus (HPV) detection by PCR.

HPV detection: - Tissues was collected from patients who underwent TORS and was stored at 8◦c till further processing. DNA was isolated from a small piece of tumor tissue and HPV DNA was detected by using PCR-based method. This method employs PCR primers specific for HPV16 E7 (Jiang and Milner, 2002). Samples positive for HPV16 DNA was further checked for HPV16 RNA expression in tissues. For this total RNA was isolated using Trizol reagent from rest of the sample and cDNA was synthesized using commercially available kits. The cDNA was used for HPV16 E7 PCR using the above-mentioned primers to confirm HPV infection. The outcome of the treatment was studied in two ways:

Table 1: Showing Demographic Variables of Patients

• Treatment perspective

• Patients’ perspective

  • Treatment perspective: The primary outcome was to see successful excision of the tumor. The secondary outcome measures was to see   outcome in relation with status of resection margins, lymph node involvement, HPV positive and HPV negative, subsite of the lesion, Tumor stage and complications if any.

  • Patients  perspective: - one-year overall survival and disease-free survival, recurrence & mortality.

The patients were followed up in the Department of Otolaryngology Head and Neck Surgery PGIMER Chandigarh. The first follow up was around 2^nd week after surgery when the Histopathological report was assessed regarding type of Tumor and the surgical margins, lymph node positivity (in patients who underwent neck dissection). All the patients were asked to follow up once in 2 months up to a period of one year.

 Patients with positive surgical resection margins and lymph node involvement were advised for adjuvant treatment with radiation therapy.

The data was entered in a predesigned proforma. Descriptive statistics was used to describe different variables. These included measures of central tendency and dispersion for continuous variables and frequencies as well as proportions for categorical variables. All point estimates were supplemented with their corresponding 95% confidence interval. All the statistical tests were two-sided and were performed at a significance level of α=0.05. Analysis was conducted using IBM SPSS STATISTICS (version 22.0)

Transoral robotic surgery (TORS) is a new tool for the management of oropharyngeal   tumors.  Robotic surgery has facilitated improved visualisation of the tissues of the oropharynx without disfiguring incisions. It also has advantages in causing less speech and swallowing dysfunction.

In our study, a total of 42 patients were followed up for a mean duration of 12 months recruited from August 2016 onwards. The surgical outcome was evaluated on various variables during these follow up visits. 

In our study men outnumbered women which is in line with the study by Patel et al., [5]. Males are more than four times as likely as females to develop oropharyngeal squamous cell carcinoma.

Mortality was found in two patients at one year follow up in our study. We also found that mortality in patients with positive surgical margins on histopathological examination was significantly more than those with free surgical margins. The difference was statistically significant (p=0.037). Moreover, as regards the mortality in patients with involved deep resection margins, patients with involved deep margins had more mortality compared to those with uninvolved deep margins(p=0.018). Hence ensuring free surgical margin resection is of paramount importance in transoral robotic surgery.

TORS may also be used selectively for patients with recurrence after primary radiation therapy with or without chemotherapy. White et al., [6] compared TORS with standard open surgery in TNM stage matched patients undergoing salvage treatment. TORS patients has significantly low rates of tracheostomy and feeding tube use and shorter hospital stay. In our study salvage surgery was done in 9 (21.4%) patients and recurrence was noted in 3 patients (33.3%) as compared with upfront surgery 2 patients (6.06%) and there was no mortality in salvage group patients as compared with 2 patients (6.0%) in upfront group at 1 year follow up. Moreover, post operative surgical margins were positive in two patients who had recurrence in patients who underwent salvage surgery. Thus, salvage surgery is the best option in patients with recurrence or after chemoradiation.

Van Loon, et al. [7] conducted the study to show the role of TORS in resection of T1-2N0 Oro-pharyngeal cancers safely and effectively, and to determine the functional and oncologic outcomes in these patients. They concluded that patients who were given postoperative radiotherapy had a worse outcome and patients treated with transoral Robotic surgery did well during follow up. They have concluded   that TORS seems to be an oncologically safe and effective surgical treatment option for early stage T1-2, N0.

Out of 9 patients with post operative resection margins positive on histo-pathological examination, 5 patients showed involved margins at the deep resection planes. Poor outcome i.e. death of 2 patients had involvement of deep resection margins. This once again signifies the importance of getting resection margins free. Clearing the disease with the free resection margins is important/crucial as the glossopharyngeal nerve runs the risk of trauma. On analysis of mortality with respect to TNM stage, we observed that mortality was not related to advanced stage of the disease. In fact, the two patients who succumbed to their disease belongs to stage II. Both the patients had positive resection margins involved and thus were subjected to post operative radiotherapy.

Li and colleagues [8] at the Sydney Head and Neck Cancer Institute found that patients with HPV positive were less likely to experience recurrence and mortality. In our study HPV p16 E7 was detected in two patients (8.7%) by PCR out of 23. HPV testing could not be done in all the patients due to logistic reasons. Both the patients were comparatively younger with age <45 years and were nonsmokers. They presented initially in TNM stage IV and there was no recurrence or mortality at 1 year follow up. Post operative radiotherapy was given to these patients owing to involvement of resection margins and lymph node metastasis.

TORS affords potential advantages and benefits over current treatment modalities. Advantages include better visualization and better access to tumors via a minimally invasive, less morbid approach, resulting in better overall functional outcome. Based on our study and comparison with the earlier studies available TORS has better outcome in terms of low surgical margins positivity rate, low rate of feeding tube use and its duration, shorter duration of surgery, low tracheostomy rate, shorter hospital stay, high rate of disease-free survival and low mortality rate.

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2. Couch ME, Zanation A. Transoral robotic surgery: disruptive or sustaining innovation?. Archives of Surgery. 2010 Sep 1;145(9):907-8.

3. Weinstein GS, O’Malley BW, Snyder W, Sherman E, Quon H. Transoral robotic surgery: radical tonsillectomy. Archives of otolaryngology–head & neck surgery. 2007 Dec 1;133(12):1220-6.

4. Kwoh YS, Hou J, Jonckheere EA, Hayati S. A robot with improved absolute positioning accuracy for CT guided stereotactic brain surgery. IEEE transactions on biomedical engineering. 1988 Feb;35(2):153-60.

5. Patel MM, Pandya AN.  Relationship of oral cancers with age, sex and site distribution and habits. Indian J Pathol, Microbiol. 2004;47:195-197.

6. White H, Ford S, Bush B, Holsinger FC, Moore E, Ghanem T, Carroll W, Rosenthal E, Sweeny L, Magnuson JS. Salvage surgery for recurrent cancers of the oropharynx: comparing TORS with standard open surgical approaches. JAMA Otolaryngology–Head & Neck Surgery. 2013 Aug 1;139(8):773-7.

7. Van Loon JWL, Smeele LE, Hilgers FJM.   Outcome of transoral robotic surgery for stage I-II oropharyngeal cancer, Eur Arch Otolaryngol. 2014;10:2939.

8. Li W, Thompson CH, O'Brien CJ, McNeil EB, Scolyer RA, Cossart YE, Veness MJ, Walker DM, Morgan GJ, Rose BR. Human papillomavirus positivity predicts favourable outcome for squamous carcinoma of the tonsil. International journal of cancer. 2003 Sep 10;106(4):553-8.