Study Assessing The "Best of" Radiotherapy vs the "Best of" Surgery in Patients With Oropharyngeal Carcinoma

Oropharyngeal Squamous Cell Carcinoma (OPSCC) arises in the soft palate, tonsils, base of tongue, pharyngeal wall, and the vallecula. Most of the patients with early stage OPSCC are usually cured. Treatment of early stage OPSCC can be successfully achieved with primary surgery including neck dissection, as indicated, or with definitive radiotherapy. The current standard treatment for OPSCC is therefore based on either surgery and/or radiotherapy, both associated with comparable, high tumor control rates but with different side effects profiles and technical constraints. In order to decrease the potential morbidity of surgery, transoral approaches have been developed within the last decades, including transoral robotic surgery (TORS), transoral laser microsurgery (TLM) or conventional transoral techniques. On the other hand, patients with head and neck cancer treated with IMRT experienced significant improvements in cause specific survival (CSS) compared with patients treated with non-IMRT techniques thus suggesting that IMRT may be beneficial in terms of patient's outcomes and toxicity profile. It is as yet unclear however, which one of the new techniques is superior to the other in terms of function preservation. Given that the functional outcome of most importance is swallowing function, the preservation of swallowing is thus of major importance. The main objective of the study is to assess and compare the patient-reported swallowing function over the first year after randomization to either IMRT or TOS among patients with early stage OPSCC, SGSCC, and HPSCC.

Eligible patients will be randomized 1 to 1 to surgery (Arm 1) or radiotherapy (Arm 2). ARM 1: Surgery Trans-oral surgery (any trans-oral approach such as trans-oral laser microsurgery conventional trans-oral surgery or trans-oral robotic surgery) will be applied to all patients in this arm. A surgical margin is defined to be clear (R0), if found to be \>/=3mm in the final specimen (except deep margin for tonsillar resection, that is either R1 or R0), is defined to be close, if 1-\<3mm, and considered to be involved (R1), if \<1mm in the final specimen. Clearly defined marginal biopsies are required for each TOS-technique. Trans-oral re-resections are required in case of R1 or close-margin to convert the patient to an R0-status.Postoperative RT or chemo-RT will be given within 5-6 weeks of surgery in case of positive. ARM 2: Radiotherapy Intensity modulated radiation therapy (IMRT) with Simultaneous integrated boost (SIB) will be applied to all patients in this arm. PTV prescription to tumor and high risk areas will be delivered daily for 5 days per week to a total dose of 66-70Gy in 2 Gy/fraction over 6 weeks, elective/prophylactic mucosal and nodal areas will receive a total dose of 54.25- 54.45 Gy in 33-35 fractions of 1.55-1.65 Gy over 6 weeks.