Biological Image Guided Antalgic Stereotactic Body Radiotherapy of Bone Metastases

Biological Image Guided Antalgic Stereotactic Body Radiotherapy of Bone Metastases: a Randomized Phase II/III Trial

In various common cancers, the skeleton is a preferred site of metastasis. These bone metastases are the most common cause of cancer-related pain, which significantly impair quality of life. It is postulated that the clinical target volume (CTV) of painful bone metastases consists of cancer cells and tumor-associated host cells: the tumor-host ecosystem. Advances in biological imaging (positron emitting tomography PET) might allow us to selectively identify the tumor-host ecosystem within the anatomical boundaries of a bone metastasis. These findings suggest the potential of intentionally non-homogenous dose escalation (dose painting by numbers) to improve pain control. The hypothesis is that fluorodeoxyglucose positron emitting tomography (FDG-PET) can detect the intra-bone metastasis regions confined with tumor-associated host-cell compartments responsible for metastasis-related pain. The primary objective is to improve pain control with biological image-guided stereotactic body radiotherapy compared to conventional radiotherapy.

Biological image-guided radiotherapy on the positron emitting tomography (PET) positive lesion with conventional dose (8Gy/ 1 fraction) will be used.

Biological image-guided stereotactic body radiotherapy (SBRT) with dose-escalation on the PET positive lesion will be used.

Pain is measured with the visual analogue scale. Response is scored in accordance to the guidelines of the international consensus on palliative radiotherapy.

Quality of life 1 month after radiotherapy measured with the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Bone Metastases Module (QLQ-BM22).

Inclusion Criteria: Painful bone metastasis of solid tumors Pain score minimum of 2 on a scale of 10 A maximum number of painful bone metastases: 3 or more Life expectancy > 3 months Age minimum 18 years old Signed informed consent Exclusion Criteria: Tumor histology (renal cell and melanoma vs. other solid tumors) VAS pain score (<5 vs. 6-10). Bisphosphonate use (yes vs. no) Opioid analgesics (yes vs. no) Corticosteroid use (yes vs. no) Spine vs non-spine localisation