Prophylactic Radiotherapy of MInimally Symptomatic Spinal Disease

Prophylactic Radiotherapy of MInimally Symptomatic Spinal Disease (PROMISSeD Trial)

Early palliative care has been shown to improve the quality of life and even survival for patients with metastatic cancer. More and more supportive oncology teams in cancer centers now advocate for early integration of radiation therapy (RT) in a patient's palliative management course. While multiple randomized studies have evaluated the efficacy of different RT regimens in the treatment of symptomatic bone lesions, few studies have examined the impact of early, upfront RT for asymptomatic or minimally symptomatic (non- opioid dependent) spine metastases and its efficacy in preventing skeletal-related events (SREs). Since the pathophysiology of spinal metastatic disease is distinct from other bony metastatic disease, the proposed trial seeks to understand whether it is beneficial to patients with minimally symptomatic disease to undergo upfront RT to reduce the risks of SREs and their sequelae, including hospitalizations.

Inclusion Criteria:

1. Histologically-confirmed solid tumor malignancy with greater than 5 sites of metastatic disease detected on cross-sectional imaging.

2. Has high-risk bone metastases that are asymptomatic or minimally symptomatic (not requiring opioids). High risk metastases are defined as:

   1. Bulkiest sites of spinal osseous disease ≥ 2cm,
   2. Disease at junctional levels, including the thoracic apex (Occiput to C2, C7-T1, T12-L2, and L5- S1)
   3. Disease with posterior element involvement, including interspinous, unilateral, or bilateral facet joints.
   4. Vertebral body compression deformity > 50%.

3. Eastern Cooperative Oncology Group (ECOG) performance status 0 - 2.

4. Age ≥ 18 years.

5. Able to provide informed consent.

6. Patients at reproductive potential must agree to practice an effective contraceptive method. Women of childbearing potential must not be pregnant or lactating.

Exclusion Criteria:

1. Previous RT to the intended treatment site that precludes developing a treatment plan that respects normal tissue tolerances.
2. Serious medical co-morbidities precluding RT.
3. Pregnant or lactating women.
4. Target lesion(s) is/are complicated bone metastases that include clinical or radiological evidence of spinal cord compression or impending pathological fracture.
5. Leptomeningeal disease.
6. Patients whose entry to the trial will cause unacceptable clinical delays in their planned management.