Postoperative Radiotherapy for Oral Squamous Cell Carcinoma After Neoadjuvant Therapy and Surgery

Study Overview
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Brief Summary
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The treatment guideline for locally advanced resectable oral squamous cell carcinoma (LAROSCC) is surgery + postoperative radiotherapy/chemoradiotherapy. Though the treatment is intensive with serious harm to quality of life, the survival of patients is poor. Neoadjuvant therapy has been evaluated in a number of clinical trials for LAROSCC, but failed to directly improve the overall survival. On the other hand, de-escalation of treatment followed by neoadjuvant is also been explored with some promising results. This study is to retrospectively include patients with LAROSCC who received neoadjuvant therapy and surgery. Survival between patients in two cohorts (cohort 1: received postoperative radiotherapy, cohort 2: received no postoperative radiotherapy) are to be compared.

Official Title
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Can Postoperative Radiotherapy be Omitted for Oral Squamous Cell Carcinoma Patients Underwent Neoadjuvant Therapy and Surgery? - A Retrospective Cohort Study

Conditions
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Radiotherapy, Neoadjuvant Therapy, Oral Squamous Cell Carcinoma, Surgery

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients receiving neoadjuvant therapy and surgery for oral squamous cell carcinoma from January 2008 to December 2021 Oral squamous cell carcinoma histology (including tongue, gingiva, cheek, floor of mouth, hard palate and posterior molar area) Clinical stage III/IVA (T1-2/N1-2/M0 or T3-4/cN0-2/M0, AJCC 2018) for the primary lesion Surgical resection samples that can be evaluated for pathological remission rate Exclusion Criteria: Severe/active systemic disease Previously radiotherapy or neck lymph node dissection for the head and neck region Evidence of tumor recurrence or metastasis in physical examination or imaging (ultrasound, CT, MRI) before initiation adjuvant radiotherapy Evidence of severe/unrelieved side effects of neoadjuvant therapy or severe postoperative complications before initiation adjuvant radiotherapy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Group1:PORT<br>Oral squamous cell carcinoma (OSCC) patients received neoadjuvant therapy, surgery, and postoperative radiotherapy. | |
| Group2:non-PORT<br>Oral squamous cell carcinoma (OSCC) patients received neoadjuvant therapy and surgery, without postoperative radiotherapy | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| OS | Overall survival | 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| LRFS | Local recurrence-free rate | 24 months | 
| QOL | Quality of life (QOL), according to the QLQ-C30 scoring manual, the final QOL scores of each field are transformed into standardized scores within 0-100 through linear transformation | 24 months | 
| OS-MPR | Overall survival for patients obtained major pathological response (MPR) from neoadjuvant therapy | 24 months |