Impact of Postoperative Radiotherapy Versus PD-1 Inhibitor Maintenance on Survival in Resectable Locally Advanced Oral and Oropharyngeal Squamous Cell Carcinoma

NCT07457099 | Not Yet Recruiting DMC

• 1 other identifier: 2025-KY-505
• Study Type: observational
• Target: 85
• Locations: 1 country
• Sites: 1

Brief Summary

Neoadjuvant immunochemotherapy (NAIC) has demonstrated promising pathological and survival outcomes in patients with resectable locally advanced oral and oropharyngeal squamous cell carcinoma (LA-OSCC/OPSCC). However, the optimal postoperative management strategy following NAIC and radical surgery remains undefined, particularly regarding the necessity of postoperative radiotherapy and the potential role of PD-1 inhibitor maintenance therapy. This single-center, ambispective cohort study aims to compare event-free survival, pathological response, survival outcomes, failure patterns, treatment-related toxicities, and functional outcomes among three postoperative strategies: postoperative radiotherapy, postoperative PD-1 inhibitor maintenance, and observation alone. The study seeks to provide real-world evidence to support risk-adapted, individualized postoperative decision-making after NAIC

Conditions

Locally Advanced Oral Squamous Cell Carcinoma; Locally Advanced Oropharyngeal Squamous Cell Carcinoma

Keywords

Neoadjuvant immunochemotherapy; oral cancer; oropharyngeal cancer; PD-1 inhibitor; postoperative radiotherapy; event-free survival; pathological response; real-world study

Outcome Measures

Primary Outcomes (2)

• 1-Year Event-Free Survival (EFS)

  Time from the date of radical surgery to the first occurrence of disease recurrence (local, regional, or distant), disease progression, death from any cause, or last follow-up, whichever occurs first.

  1-Year

• Pathological Complete Response (pCR) Rate

  Pathological complete response (pCR) is defined as the absence of residual viable tumor cells in both the primary tumor site and all resected lymph nodes, as assessed by postoperative histopathological examination.

  At the time of surgery

Secondary Outcomes (8)

• 1-Year Overall Survival (OS)

  1-Year

• Major Pathological Response (MPR) Rate

  At the time of surgery

• Failure Patterns

  1-Year

• Incidence of Grade ≥3 Radiotherapy-Related Toxicities (RTOG/EORTC)

  1-Year

• Incidence of Grade ≥3 Immunotherapy-Related Adverse Events (NCI-CTCAE v6.0)

  1-Year

Study Arms (3)

No Adjuvant Therapy Group

Patients received neoadjuvant immunochemotherapy followed by R0 radical surgery, with no postoperative adjuvant treatment and routine follow-up only.

Other: Observation

Postoperative Radiotherapy Group

Patients received neoadjuvant immunochemotherapy followed by R0 radical surgery and postoperative radiotherapy according to multidisciplinary team decision.

Radiation: Postoperative Radiotherapy

Postoperative Immunotherapy Maintenance Group

Patients received neoadjuvant immunochemotherapy followed by R0 radical surgery and postoperative PD-1 inhibitor maintenance therapy.

Drug: PD-1 Inhibitor Maintenance Therapy

Interventions

Observation OTHER

Participants received neoadjuvant immunochemotherapy followed by R0 radical surgical resection. No postoperative adjuvant therapy was administered. Patients were managed with routine clinical follow-up, including scheduled physical examinations, imaging assessments, and functional evaluations according to institutional practice.

Also known as: No postoperative adjuvant therapy, Active surveillance, Observation only

No Adjuvant Therapy Group

Postoperative Radiotherapy RADIATION

Participants received neoadjuvant immunochemotherapy followed by R0 radical surgical resection and postoperative radiotherapy. Radiotherapy was delivered to the primary tumor bed and regional lymphatic drainage areas according to multidisciplinary team recommendations and institutional guidelines.

Also known as: Adjuvant radiotherapy, Postoperative radiation therapy (PORT), Radiation therapy after surgery

Postoperative Radiotherapy Group

PD-1 Inhibitor Maintenance Therapy DRUG

Participants received neoadjuvant immunochemotherapy followed by R0 radical surgical resection and postoperative immunotherapy maintenance with a PD-1 inhibitor. Immunotherapy was administered at standard dosing intervals according to institutional protocols until disease progression, unacceptable toxicity, or completion of the planned treatment course.

Also known as: Programmed cell death protein 1 inhibitor, Immune checkpoint inhibitor maintenance, PD-1 antibody maintenance

Postoperative Immunotherapy Maintenance Group

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adult patients (18-80 years) with histologically confirmed, treatment-naïve, locally advanced oral or oropharyngeal squamous cell carcinoma who were surgically resectable and had ECOG performance status 0-1. All participants received two cycles of neoadjuvant immunochemotherapy (tislelizumab plus paclitaxel and platinum) followed by R0 radical surgery and were managed postoperatively with radiotherapy, PD-1 inhibitor maintenance, or observation. Patients with prior head and neck radiotherapy, active autoimmune disease, uncontrolled severe comorbidities, pregnancy/lactation, or incomplete data were excluded.

You may qualify if:

• Age 18-80 years, any gender.
• Expected survival ≥ 6 months.
• Adequate major organ function; ECOG performance status 0-1.
• Treatment-naïve patients diagnosed with locally advanced oral squamous cell carcinoma (LA-OSCC) or locally advanced oropharyngeal squamous cell carcinoma (LA-OPSCC), in accordance with the 8th edition of the American Joint Committee on Cancer (AJCC) staging system (2017) and the 2020 Chinese Stomatological Association (CSA) guidelines for pathological diagnosis of oral and oropharyngeal cancers, with clinical stages: cT3N0M0, cT1-3N1M0, cT4aN0-2M0, cT1-4aN3M0, or cT4bN0-3M0.
• No evidence of distant metastasis based on auxiliary examinations.
• No prior antitumor treatment, including surgery, radiotherapy, chemotherapy, immunotherapy, targeted therapy, or other antitumor therapies.
• Received 2 cycles of neoadjuvant chemoimmunotherapy (toripalimab + TP regimen) and underwent R0 resection.
• Women of childbearing potential must agree to use effective contraception during treatment and for 3 months after.
• Signed informed consent (if the participant lacks capacity, by a legally authorized representative), voluntarily participates in the study, and demonstrates good compliance.

You may not qualify if:

• History of radiotherapy to the head and neck region.
• Severe bone marrow suppression, hepatic or renal failure, or uncontrolled severe infections, cardiovascular diseases, or other conditions that may preclude tolerance of treatment.
• Active autoimmune diseases, history of organ transplantation requiring long-term immunosuppressive therapy, or severe immunodeficiency that may result in serious immune-related adverse events.
• Active infections requiring systemic therapy.
• Cardiovascular/cerebrovascular events within 6 months prior to study treatment, including myocardial infarction, severe/unstable angina, coronary or peripheral artery bypass surgery, symptomatic heart failure, cerebrovascular accident, transient ischemic attack, or symptomatic pulmonary embolism.
• Bleeding tendency/disorders: clinically significant bleeding or clear bleeding tendency within the past 28 days, including but not limited to gastrointestinal bleeding, epistaxis (excluding mild nosebleeds or blood-streaked sputum), or persistent bleeding/clotting disorders.
• History of substance abuse, alcoholism, or drug abuse.
• Pregnant or breastfeeding women.
• Participation in other interventional clinical trials simultaneously.

Sponsors & Collaborators

• Zhujiang Hospital: lead

Study Sites (1)

Department of Stomatology, Zhujiang Hospital, Southern Medical University, Haizhu District, Guangzhou, Guangzhou, Guangdong 510282

Guangzhou, China

Location

MeSH Terms

Conditions

Mouth Neoplasms; Oropharyngeal Neoplasms

Interventions

Observation; Watchful Waiting; Radiotherapy, Adjuvant; Immune Checkpoint Inhibitors

Condition Hierarchy (Ancestors)

Head and Neck Neoplasms; Neoplasms by Site; Neoplasms; Mouth Diseases; Stomatognathic Diseases; Pharyngeal Neoplasms; Otorhinolaryngologic Neoplasms; Pharyngeal Diseases; Otorhinolaryngologic Diseases

Intervention Hierarchy (Ancestors)

Methods; Investigative Techniques; Outcome Assessment, Health Care; Outcome and Process Assessment, Health Care; Quality of Health Care; Health Services Administration; Combined Modality Therapy; Therapeutics; Radiotherapy; Molecular Mechanisms of Pharmacological Action; Pharmacologic Actions; Chemical Actions and Uses; Antineoplastic Agents, Immunological; Antineoplastic Agents; Therapeutic Uses

Central Study Contacts

Xiaozhi LV

CONTACT

02062783160; lxzsurgeon@126.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: OTHER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 25, 2026
• First Posted: March 9, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): August 30, 2026
• Study Completion (Estimated): June 30, 2028
• Last Updated: March 9, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)