Transoral Surgical Resection Followed by De-escalated Adjuvant IMRT in Resectable p16+ Locally Advanced Oropharynx Cancer

Time to recurrence, defined as local and/or regional progression (identification of disease growth that is present within the area in which it was first located) and/or distant metastasis (identification of disease growth that is present in area(s) distant to that previously located). Local progression is defined as progression at the primary tumor site. Regional progression is defined as progression in the draining lymphatics (typically the cervical, retropharyngeal/retrostyloid and supraclavicular lymph nodes). Distant progression is defined as tumor recurrence in one or more non-local and non-regional sites (e.g., bone, lung, liver, etc.). Recurrent malignancy will be determined based on clinical exam and imaging findings. Patients who are disease-free but who die from other causes will be censored.

Loco-regional control will be evaluated based on the percentage of patients without recurrence (identification of disease growth) in the primary site or regional lymphatics based on imaging and/or clinical exam.

Loco-regional control will be evaluated based on the percentage of patients without recurrence (identification of disease growth) in the primary site or regional lymphatics based on imaging and/or clinical exam.

Percentage of patients with distant metastasis (identification of disease growth that is present in area(s) distant to that previously located) evident on imaging and/or clinical exam. Distant metastasis is defined as tumor recurrence in one or more non-local (at the primary tumor) and non-regional (draining lymphatic) sites such as bone, lung, liver, etc.

Percentage of patients with distant metastasis (identification of disease growth that is present in area(s) distant to that previously located) evident on imaging and/or clinical exam. Distant metastasis is defined as tumor recurrence in one or more non-local (at the primary tumor) and non-regional (draining lymphatic) sites such as bone, lung, liver, etc.

Overall survival will be measured as the time from start of treatment to death from any cause.

Overall survival will be measured as the time from start of treatment to death from any cause.

The percentage of total patients enrolled in the study allocated to low (Arm S), intermediate (Arm RT) and high risk (Arm CRT) groups. Histologic risk features are defined as follows: Low risk (ARM S) - T1-T2 AND 0 or 1 metastatic lymph nodes AND <3 cm AND clear (≥3mm) margins AND no extracapsular extension (ECE) AND no perineural invasion AND no lymphovascular invasion; Intermediate risk (ARM RT) - Any of the following features: One or more close (<3mm) margins, OR "minimal" ≤1 mm ECE OR 1 or more metastatic lymph nodes >3 cm in diameter OR 2-4 lymph nodes positive (≤ 6 cm in diameter), OR perineural invasion OR lymphovascular invasion; High risk (ARM CRT) - Any of the following features: One or more positive margins OR >1 mm ECE OR ≥ 5 metastatic lymph nodes.

The percentage of patients that have a feeding tube, by Arm, for the low (Arm S), intermediate (Arm RT) and high risk (Arm CRT) groups following treatment with transoral resection and adjuvant therapy.

Number of patients experiencing toxicities related to study treatment per Common Terminology Criteria for Adverse Events (CTCAE v5.0) determined at each follow-up summarized by frequency and grade.

FACT-HN is a self-administered questionnaire. Item responses are on a Likert scale score ranging from 0 to 4. Individual responses are summed to compute subscale scores, and the subscales to compute overall total scores. FACT-HN includes 2 parts - FACT-G and FACT-HN. The basic FACT-G (general) is comprised of 27 items, with four subscales including Physical Well-Being (score = 0-28), Social/Family Well-Being (score= 0-28), Emotional Well-Being (score = 0-24), and Functional Well-Being, (score = 0-28), for a total score min/max = 0-108. The FACT-HN is comprised of 12 head and neck specific items (0-48). Thus, the overall total possible score range is 0-156. Analysis will include the FACT Head & Neck Trial Outcome Index, a composite score which includes only physical, functional, and FACT-HN, thus, scores range from 0-104. Higher scores indicate better Quality of Life.

Patient-reported swallowing perception and performance using MDASI-HN measures treatment related symptom burden in head and neck cancer patients. The 20-item MDASI measures both severity and burden of symptoms and their effect on patients' daily activities, using a numeric rating scale of 0-10. This instrument includes 13 core symptoms and 9 head and neck specific items. Higher scores indicate superior perception of function.

Three swallowing outcomes will be rated by the SLP conducting the MBS study and reported by research staff: 1) laryngeal penetration (yes, no); 2) aspiration (no, sensate, silent), and 3) pharyngeal residue (no, < 50%, > 50%). These have been selected as universal items generally reported by swallowing clinicians that have been shown to significantly predict pneumonia in patients with oropharyngeal cancers. Prevalence of these dysphagia endpoints will be estimated at each time point.

Patient-reported voice outcomes will be assessed using the Voice Handicap Index-10 (VHI-10) survey. The VHI-10 is a patient self-assessment instrument that quantifies patients' perception of their voice handicap. It evaluates patient's physical (P), emotional (E), and functional (F) perceptions of voice and has shown to be highly reliable for internal consistency and test-retest stability. The VHI-10 utilizes a 10-item questionnaire in which the patient circles the response that most accurately reflects his or her own experience on a linear scale (from "never" to "always"). "Always" response is scored 4 points, a "Never" response is scored 0. The remaining options are scored between 1 and 3 points. The tallied number of points for each of the subscales is computed to a total composite score. The patient's values are compared to published norms.

The Performance Status Scale (PSS-HN) is a clinician-rated instrument consisting of 3 questions: normalcy of diet, public eating/swallowing, and understandability of speech subscales in patients with head and neck cancer. Each subscale is rated from 0 to 100, with higher scores indicating better performance.

Patient-reported swallowing-related quality of life will be measured using the MD Anderson Dysphagia Inventory (MDADI). It evaluates the patient's physical (P), emotional (E) and functional (F) perceptions of swallowing dysfunction. The MDADI is a 20-item questionnaire in which the patient circles the response that best reflects their experience in the past week on a 5-point Likert Scale with answers ranging from "Strongly Agree" (scored as 1 point on all questions except E7 and F2, where it is scored as 5 points) to "Strongly Disagree" (scored as 5 points on all questions except E7 and F2, where it is scored as 1 point). Scores for individual questions are summed and averaged to obtain a composite score ranging from 20 (extremely low swallow functioning) to 100 (high swallow functioning).