A Randomized Phase II Study of Stereotactic Ablative Body Radiotherapy for Metastases to the Lung (TROG 13.01 SAFRON II)

Stereotactic Ablative Fractionated Radiotherapy Versus Radiosurgery for Oligometastatic Neoplasia to the Lung: A Randomised Phase II Trial

The main purpose of this study is to determine the safety (defined as number of participants experiencing ≥ 5% toxicity at 12 months post treatment) of stereotactic ablative fractionated radiotherapy versus radiosurgery for oligometastatic neoplasia to the lung.

Stereotactic Ablative Body Radiotherapy (SABR) is an exciting novel radiotherapy technique that is delivered over very few sessions. In the case of limited pulmonary 'oligometastases', SABR can result in long-term survival. It is non-invasive and associated with high rates of tumour control and relatively low toxicity. Additionally, the large doses of precision radiotherapy involved may evoke a strong immune response to recognise and attack any remaining tumour cells. In the future, SABR may be an attractive alternative to invasive surgery. There are two SABR techniques emerging in Australia; fractionated and single fraction treatments. We aim to conduct the first clinical trial of SABR in patients with limited pulmonary metastases testing fractionated versus single fraction treatments.

The primary aim of this study is to evaluate the toxicity, Quality of Life, clinical efficacy and cost effectiveness of single fraction SABR compared to multi-fraction SABR in patients with oligometastases to the lung.

The secondary aim of this study is to assess the immune response evoked by both fractionated and single fraction SABR and its prognostic implications for patient outcomes.

Inclusion Criteria:

1. A maximum of three metastases to the lung from any non-haematological malignancy
2. Tumour diameter ≤5cm
3. Targets are located away from central structures (defined as 2cm beyond bifurcation of lobar bronchi and central airways). Targets in proximity to chest wall and mediastinum that meet these inclusion criteria are eligible.
4. Patients must be medically inoperable, technically high risk or have declined surgery.

Exclusion Criteria:

1. Previous high-dose thoracic radiotherapy.
2. Cytotoxic chemotherapy within 3 weeks of commencement of treatment, or concurrently with treatment. Hormonal manipulation agents are not excluded (e.g. aromatase inhibitors, selective oestrogen receptor modulators, and gonadotrophin releasing hormone receptor modulators)
3. Targeted agents (such as sunitinib and tarceva) within 7 days of commencement of treatment, or concurrently with treatment.