While radiotherapy is a highly effective cancer treatment — useful for about 60 per cent of all cancers — it may lead to residual cancer that has the potential to hide behind clear scans and lead to worse outcomes, according to a study.
Residual cancer is microscopic levels of cancer cells that are left behind after cancer treatments. These are often not visible on scan images, which can be misleading, argued researchers from the University of Chicago Medical Center in the US.
In an editorial, published in the journal Oncotarget, they said that this “residual disease” is more common than expected and is linked to worse long-term outcomes.
Residual cancer is identified on histology in 40 per cent of the lung, 57-69 per cent of renal cell, 7.7-47.6 per cent of prostate, and 0-86.7 per cent of hepatocellular carcinoma,” Dr. Muzamil Arshad from the varsity.
The expert called “for a rethinking of how treatment success is judged and how cancer is followed up after therapy”. Radiotherapy — especially a form known as stereotactic ablative radiotherapy (SABR) — is widely used to treat cancers in the lung, liver, prostate, and other organs.