Oligometastatic cancer refers to a type of cancer that has disseminated from its original (primary) location – whether it be lung, breast, or colon cancer – to a limited number of secondary sites. This condition is often categorised based on the number of metastases present, which may include a solitary isolated metastasis, three or fewer metastases, or five or fewer metastases. Some definitions extend to include cancers with up to ten metastases.

However, the most widely accepted definition of oligometastatic cancer currently applies to patients with metastatic disease who have five or fewer sites of cancer in other organs. These sites can include bone, liver, or brain metastases. The objective is to differentiate this group of patients with a small number of metastatic sites from those with widespread metastatic disease affecting multiple locations. This distinction is crucial because, despite both groups being classified as stage 4 cancer, the treatment approaches for these two scenarios differ significantly.

It remains unclear why some patients develop cancer that disseminates to only one or two sites, while others experience widespread cancer.

Extensive research is currently being conducted to elucidate why tumours exhibit disparate behaviour, despite appearing virtually identical under microscopic examination. Specifically, researchers are investigating why, in one patient, tumours may spread to only one or two sites, whereas in another patient, they may disseminate to multiple locations (exceeding five or even ten sites).

Considerable attention has been focused on this aspect of oligometastatic cancer, as it is believed that, despite patients having advanced cancer (stage 4 with five or fewer sites of metastatic disease), overall survival can be prolonged, and in a small proportion of cases, potentially even cured. However, achieving this outcome would require treatment combining chemotherapy with local therapies – such as surgery, radiation, or radiofrequency ablation – applied directly to the various metastatic sites to control the cancer.

Cancer is deemed cured when it is entirely eradicated and does not recur, a state also referred to as complete remission. Your doctor may declare that your cancer is cured if you remain disease-free for more than ten years following treatment.

In certain instances, oligometastatic cancer can be cured. However, more extensive and long-term clinical trials are required to determine how many individuals with oligometastatic cancer remain disease-free for ten years post-treatment.

A phase two clinical trial known as SABR-COMET revealed that over four in ten participants survived for at least five years after undergoing radiotherapy in conjunction with standard treatment, including those with oligometastatic cancer affecting the breast, prostate, oesophagus, skin, and colon.

Further research is required to fully comprehend survival rates for oligometastatic disease. It is probable that these rates will vary depending on the nature of disease progression – whether it is de novo, metachronous, or induced – and the location of the metastases. Additionally, survival rates may be influenced by the type of primary cancer, although not all studies have confirmed this correlation.

Your doctor is the most suitable person to provide guidance on survival rates specific to your cancer. They will be able to take into account all the unique factors that may impact your prognosis.

It is essential to acknowledge that while side effects can arise with SABR, they are generally mild and transient, causing minimal disruption to most patients’ daily routines. The frequency and severity of side effects can fluctuate based on factors such as the size and location of the tumour, the dose of radiation administered, and your individual health concerns. Common mild to moderate side effects, such as fatigue, are typically well-tolerated and manageable with supportive care measures. Before commencing treatment, I will provide you with a contact number that offers access to support and care around the clock, should you have any concerns about your symptoms.

Your doctor is the most suitable person to provide guidance on survival rates specific to your cancer. They will be able to take into account all the unique factors that may impact your prognosis.