Non-interventional Observational Study of Stereotactic Body Radiotherapy for Oligometastatic Non Small Cell Lung Carcinoma (NSCLC).

Background and objectives:

In a selected population of NSCLC patients, local treatment of oligometastases with radiotherapy has been proven feasible but has never been evaluated in a prospective way. The aim of this study is to assess the efficacy and toxicity of stereotactic body radiotherapy (i.e. the delivery of high dose radiotherapy in a few fractions) in the treatment of oligometastatic NSCLC patients. The primary objective is to evaluate the metabolic complete response rate by performing a PET-CT scan at baseline and 3 months after initiation of radiotherapy. Secondary objectives are progression-free survival, local control rate, overall survival, acute and late toxicity.

Inclusion criteria:

Cohort 1: patients with Stage IV NSCLC (with  5 metastases) not amenable for (further) systemic treatment
Cohort 2: patients with Stage IV NSCLC achieving best response (stable disease - partial response) after first line chemotherapy but still presenting active disease (with  5 metastases).

Study plan:

A PET-CT scan will be performed before start of treatment. The treatment is carried out with the VERO SBRT system or using rotational intensity-modulated radiotherapy (helical tomotherapy or VMAT), delivering a dose of 50 Gy in 10 fractions (5 fractions a week). Three months after the start of radiotherapy, the response will be evaluated by PET-CT.

Simon two-stage design for phase 2 studies ( =  = 0,10):
Cohort 1: acceptable and unacceptable complete metabolic response probability: 20% & 7%  sample size for first and second stage: 1/22 & 5/45 (accrual: 1)
Cohort 2: acceptable and unacceptable complete metabolic response probability: 15% & 30%  sample size for first and second stage: 3/23 & 11/55 (accrual: 2)