This prospective observational cohort study will evaluate different radiotherapy target volume delineation patterns in patients with locally advanced esophageal squamous cell carcinoma receiving radiotherapy combined with immunotherapy.
In routine clinical practice, physicians may use different margins around the primary tumor and different approaches to regional lymph node irradiation. The study will not assign participants to a specific radiotherapy strategy. Instead, participants will receive treatment according to routine clinical practice, and the actual radiotherapy plans will be recorded and analyzed.
The study will compare locoregional tumor control, recurrence patterns, survival, treatment-related toxicity, lymphocyte reduction, and completion of immunotherapy among patients receiving different target volume strategies. The main objective is to evaluate 2-year locoregional recurrence-free survival and to identify radiotherapy approaches that may achieve effective tumor control while reducing unnecessary radiation exposure and treatment-related toxicity.
Age 18 to 80 years, regardless of sex.
Histologically confirmed esophageal squamous cell carcinoma.
Clinical stage cT2-4aN0-3M0, or considered by a multidisciplinary team to be suitable for definitive immunotherapy combined with radiotherapy or preoperative immunotherapy combined with radiotherapy.
Planned to receive one of the following modern precision radiotherapy techniques: IMRT, VMAT, TOMO, proton therapy, or heavy-ion radiotherapy.
Presence of distant metastasis or malignant pleural or peritoneal effusion.
Previous thoracic radiotherapy that may affect the current target volume design or dose constraints.
Pre-existing esophagotracheal fistula, esophagoaortic fistula, or a high risk of perforation considered unsuitable for radiotherapy.
Active interstitial lung disease, severe infection, or uncontrolled autoimmune disease considered unsuitable for immunotherapy.
Patients with locally advanced esophageal squamous cell carcinoma who are treated at the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College and are considered suitable for definitive or preoperative radiotherapy combined with immunotherapy will be prospectively and consecutively enrolled. Treatment decisions will be made according to routine clinical practice. Participants will be followed to evaluate the association between actual radiotherapy target volume delineation patterns and locoregional control, recurrence, survival, toxicity, lymphocyte reduction, and immunotherapy completion.
Cohort
Prospective
GTV-CTV Longitudinal Margin
RadiationThe longitudinal margin from the gross tumor volume (GTV) to the clinical target volume (CTV) actually used in routine clinical practice will be recorded and analyzed. The study protocol does not assign a specific margin.
Regional Lymph Node Irradiation Strategy
RadiationThe extent of regional lymph node irradiation actually used in routine clinical practice, including involved-field irradiation and approaches incorporating partial elective nodal irradiation, will be recorded and analyzed. The study protocol does not assign a specific nodal irradiation strategy.
2-Year Locoregional Recurrence-Free Survival
Locoregional recurrence-free survival (LRFS) is defined as the time from the start of radiotherapy to locoregional tumor recurrence, death from any cause, loss to follow-up, or the last follow-up, according to the study protocol. The 2-year LRFS rate will be compared among patients receiving different radiotherapy target volume delineation strategies.
2-Year Overall Survival
Overall survival (OS) is defined as the time from the start of radiotherapy to death from any cause, loss to follow-up, or the last follow-up. The 2-year overall survival rate will be evaluated among participants receiving different radiotherapy target volume strategies.
Marginal and Regional Recurrence Rate
The proportion of participants who develop marginal recurrence or regional lymph node recurrence during follow-up. Recurrence will be determined by pathological or cytological confirmation when available, or by serial imaging showing a new or progressively enlarging lesion consistent with recurrence.
Incidence of Grade 3 or Higher Treatment-Related Toxicity
The incidence of grade 3 or higher treatment-related adverse events will be assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 5.0. Toxicities of interest include radiotherapy-related and systemic treatment-related adverse events.
Click on the lead sponsor to view all of their trials.
