Stereotactic Body Radiotherapy for Oligometastatic Cancers

Stereotactic body radiotherapy (SBRT) delivers very high doses of radiation with sub-millimetre precision to extracranial metastatic lesions, typically in one to five fractions. In the oligometastatic setting—defined by the presence of a limited number of metastatic deposits—SBRT aims to achieve durable local control, delay systemic progression and, in selected patients, offer long-term survival benefit. Technical advances in image guidance, motion management and treatment planning have reduced toxicity to surrounding normal tissues and expanded indications to multiple organ sites, including lung, liver, adrenal gland and bone. Patient selection has evolved from purely anatomical criteria to incorporate molecular and liquid-biopsy biomarkers, enabling identification of micrometastatic disease and stratification of risk. Randomised trials have established improvements in progression-free survival and overall survival with consolidative SBRT, while large registries and pooled analyses continue to refine dose–response relationships and prognostic factors. Globally, SBRT is now integrated within multidisciplinary pathways alongside surgery, systemic therapy and immunotherapy, emphasising its role as a safe, effective and reproducible metastasis-directed modality.

Research from Nature Portfolio

Projections based on population registries have forecast a gradual shift towards more indolent forms of metastatic cancer by 2040, with a corresponding increase in five-year survivorship. This epidemiological trend underscores the growing clinical relevance of local ablative strategies for patients with limited metastatic burden and supports resource allocation for SBRT programmes.

An integrative molecular study of colorectal liver metastases has defined subtypes characterised by differential immune activation, angiogenic signatures and oncogenic mutations. Patients whose metastases exhibit pronounced immune infiltration and absence of aggressive genetic drivers achieve ten-year overall survival rates approaching those observed after curative resection. These findings provide a molecular framework for selecting patients most likely to benefit from focal therapies such as SBRT and validate the biological basis of a curable oligometastatic state.

Stereotactic Body Radiotherapy for Oligometastatic Cancers publication trend

The graph below shows the total number of articles in stereotactic body radiotherapy for oligometastatic cancers across all publications each year (not limited to Nature Index journals).

Technical terms

Stereotactic Body Radiotherapy (SBRT): A form of high-precision radiotherapy delivering ablative doses to extracranial lesions in a few fractions while sparing adjacent normal tissues.

Oligometastasis: A clinical state with a limited number (typically up to five) of metastatic lesions, amenable to curative-intent local therapies.

Circulating Tumour DNA (ctDNA): Fragments of tumour-derived DNA detectable in plasma, used as a non-invasive biomarker for minimal residual disease and treatment response.

Restricted Mean Survival Time (RMST): The average event-free or overall survival time up to a specified follow-up horizon, offering a robust and interpretable summary of treatment effect.

Biologically Effective Dose (BED): A calculated radiobiological parameter that accounts for total dose and fractionation, used to compare different radiotherapy regimens.

References

1. Future trends in incidence and long-term survival of metastatic cancer in the United States. Communications Medicine (2023).
2. Integrated molecular subtyping defines a curable oligometastatic state in colorectal liver metastasis. Nature Communications (2018).
3. Assessing the effect of metastasis-directed therapy in oligometastatic disease using the restricted mean survival time. British Journal of Cancer (2024).
4. Pre-radiotherapy ctDNA liquid biopsy for risk stratification of oligometastatic non-small cell lung cancer. npj Precision Oncology (2023).
5. Stereotactic Body Radiotherapy (SBRT) for liver metastasis – clinical outcomes from the international multi-institutional RSSearch® Patient Registry. Radiation Oncology (2018).