RecruitingPhase 3NCT07008716

Omitting CTV for Primary Tumor in LS-SCLC

Omission of Clinical Target Volume (CTV) for Primary Tumors in Limited-Stage Small Cell Lung Cancer: A Prospective Multicenter Randomized Controlled Trial

Sponsor

Sun Yat-sen University

Enrollment

852 participants

Start Date

Jun 3, 2025

Study Type

INTERVENTIONAL

Conditions

Radiotherapy Side Effect Progression SCLC, Limited Stage Radiation Exposure

Summary

This randomized controlled non-inferior trial prospectively enrolled patients with limited-stage small cell lung cancer (LS-SCLC). Patients in the experimental group would receive radiotherapy with omission of the clinical target volume (CTV) for the primary tumor, while those in the control group would receive radiotherapy including CTV. The efficacy and toxicity of the two groups are compared to provide evidence for the radiotherapy of LS-SCLC. The target volume of LS-SCLC may be reduced by omitting CTV without increasing local recurrence but potentially reducing the dose to organs at risk and the side effects.

Eligibility

Min Age: 18 YearsMax Age: 75 Years

Inclusion Criteria9

Small cell lung cancer confirmed by histology or cytology; TNM stage IA-IIIC (AJCC 8th edition, 2017; limited-stage) without intrapulmonary metastasis;
Aged 18-75 years, KPS score ≥ 80, ≤ 10% weight loss within the past 6 months;
Have measurable lesions per RECIST 1.1 criteria;
Have no disease progression after 2-4 cycles of etoposide/carboplatin or etoposide/cisplatin;
Lung function test: FEV1 ≥ 1 L (Optional);
Complete blood count: neutrophil count ≥ 1.5 x 10\^9/L, hemoglobin ≥ 100 g/L, platelet count ≥ 100 x 10\^9/L;
Renal function: serum creatinine ≤ 1.5 x upper limit of normal (ULN);
Liver function: AST and ALT ≤ 2.5 x ULN, bilirubin ≤ 1.5 x ULN;
Fully understand the study, able to complete treatment and follow-up, and voluntarily sign the informed consent.

Exclusion Criteria8

Other malignant tumors (prior or concurrent), except those that have been curatively treated with disease-free survival ≥ 5 years, such as non-melanoma skin cancer, cervical carcinoma in situ, or early-stage papillary thyroid cancer;
Uncontrolled heart disease or myocardial infarction within the past 6 months;
Patients with a history of mental illness;
Pregnant and lactating patients;
Poorly controlled diabetes and hypertension;
Interstitial pneumonia or active pulmonary fibrosis;
Active infection;
Other conditions unsuitable for enrollment (per investigator judgment).

Interventions

RADIATIONRadiation Therapy

Twice-daily (45 Gy/30 fractions) or once-daily (45 Gy/15 fractions) thoracic radiotherapy after 2-4 cycles of chemotherapy

DRUGEtoposide + carboplatin; Etoposide + cisplatin

Carboplatin IV (AUC=5) on day 1 combined with etoposide IV (100mg/m2) on days 1-3, or cisplatin IV (25mg/m2) on days 1-3 combined with etoposide IV (100mg/m2) on days 1-3. Treatment is repeated every 21 days for 4-6 cycles.

RADIATIONCreating CTV for primary tumor

A margin of 0.8 cm beyond the gross target volume of primary tumor.

RADIATIONprophylactic cranial irradiation (PCI)

Beginning 4-6 weeks after chemoradiotherapy completion, patients in both arms who achieve a complete or partial response without brain metastasis receive PCI at 25 Gy/10 fractions or 26 Gy/13 fractions, delivered once daily (5 days per week).