Watch: the CureRays® explainer series
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What is metastatic cancer?
Metastatic cancer is cancer that has spread from where it started (the primary tumor) to other parts of the body, such as the bone, liver, lung, or brain. For a long time, metastatic disease was treated only to control symptoms. That's changing. When the spread is limited to just a few spots — called oligometastatic disease (often 1 to 5 lesions) — treating each one with precise, high-dose radiation can extend survival and, in some cases, offer a chance at long-term control. CureRays focuses on this hopeful middle ground between early and widespread disease.
The main types
Doctors group metastatic cancer by where it starts and how it behaves:
| Type | What it means, simply |
|---|---|
| Oligometastatic | A limited number of metastases (often 1-5). The most promising group for aggressive, potentially curative local treatment. |
| Bone metastases | Spread to the bone; radiation relieves pain quickly and can also control the disease at that site. |
| Brain metastases | Spread to the brain; often treated with focused stereotactic radiosurgery, sometimes in a single session. |
| Widespread (polymetastatic) | Many sites of spread; treated mainly with whole-body (systemic) medicine, with radiation to ease specific symptoms. |
Staging, in plain terms
Metastatic cancer is classified as Stage IV, but the modern question is how MANY and how WIDESPREAD the metastases are. A few isolated spots (oligometastatic) are approached very differently — and more aggressively — than widespread disease, because limited spread may still be curable.
| Stage IV (extent of spread) | What it generally means |
|---|---|
| Oligometastatic | Only 1-5 metastases. Each can often be targeted with stereotactic radiation alongside systemic therapy, aiming for long-term control. |
| Oligoprogressive | Mostly controlled disease with one or a few spots starting to grow; radiation can treat those spots without changing the whole plan. |
| Symptomatic metastases | Spots causing pain or pressure; radiation provides fast, effective relief. |
| Widespread | Many sites of disease; systemic medicine leads, with radiation used to ease specific problem areas. |
The standard of care
Metastatic Cancer is almost always treated by a team that may include a surgeon, a medical oncologist, and a radiation oncologist, combining therapies for the best result. The usual building blocks are:
Systemic therapy
Whole-body treatment — chemotherapy, hormone therapy, targeted drugs, or immunotherapy — remains the foundation for metastatic cancer.
Stereotactic ablative radiation (SABR/SBRT)
For oligometastatic disease, high-dose precise radiation to each metastasis can extend survival when added to systemic therapy.
Palliative radiation
Short courses of radiation that quickly relieve pain, bleeding, or pressure from a metastasis — improving quality of life.
Stereotactic radiosurgery (SRS)
Pinpoint single-session radiation for brain metastases, sparing healthy brain tissue.
How radiation treatment works
Radiation uses focused, high-energy beams to damage the DNA of cancer cells so they can no longer divide. In metastatic disease it serves two roles. As stereotactic ablative radiation, it concentrates a very high dose on a small target to wipe out an individual metastasis while sparing healthy tissue — useful when only a few spots exist. As palliative radiation, a few gentle sessions quickly relieve pain or pressure caused by a tumor. Both are precise, painless, and increasingly used alongside modern systemic medicines to help people live longer and better.
The main ways radiation is delivered for metastatic cancer:
Stereotactic ablative radiotherapy (SABR)
Delivers very high, precisely targeted doses to a metastasis in just 1-5 sessions, destroying it while sparing surrounding tissue — the technique behind the SABR-COMET results.
Stereotactic radiosurgery (SRS)
Concentrates radiation on small brain metastases in a single accurate session, with no incision and rapid recovery.
Conventional palliative radiation
A few short treatments aimed at a painful or troublesome site for fast, durable symptom relief.
Latest studies shaping care
Care keeps improving — often toward getting the same excellent results with less burden on patients. A few developments:
SABR-COMET (long-term results): In this randomized trial, adding stereotactic radiation to all metastases in oligometastatic patients improved median overall survival by about 22 months versus standard care alone, and roughly doubled progression-free survival.[1]
SABR-COMET phase II, JCO long-term results
SABR-COMET-3 (ongoing): A larger phase III trial is now testing stereotactic radiation for patients with 1-3 metastases to confirm the survival benefit and define its role as standard care.[2]
SABR-COMET-3 randomized trial
Oligometastatic momentum: Growing evidence across cancer types supports treating limited metastases aggressively with focused radiation rather than systemic therapy alone, expanding the goal from control toward long-term remission.[3]
Oligometastatic literature reviews
Common questions
Does metastatic cancer mean it can't be cured? Not necessarily anymore. When spread is limited to a few spots (oligometastatic), focused radiation added to systemic therapy can sometimes achieve long-term control — a real shift from treating only symptoms.
Can radiation help with pain? Yes. Palliative radiation is very effective at relieving pain from bone and other metastases, often within days to weeks, using just a few short sessions.
How many radiation sessions are needed? Stereotactic treatments often take just 1-5 sessions; palliative courses may be a single treatment or a handful, depending on the goal and location.
References
Numbered sources for the studies cited above. Links open the primary publication on PubMed or the publisher’s site.
- SABR-COMET phase II, JCO long-term results (no indexed identifier — see your care team) ↩
- SABR-COMET-3 randomized trial (no indexed identifier — see your care team) ↩
- Oligometastatic literature reviews (no indexed identifier — see your care team) ↩