How to Test for Cancer?
Your doctor is likely to request a few tests depending on whether cancer is being suspected. The nature of the test(s) can vary considerably depending on your symptoms although often a blood test would be performed in the first instance as a baseline. Sometimes, the blood test could be looking directly for cancer cells (e.g. PSA for prostate cancer, Ca125 for ovarian cancer – though neither of these tests are very sensitive for their respective cancers, etc.) or indirectly, as something likely to have been caused by the cancer (e.g. iron deficiency anaemia for possible bowel cancer, elevated liver function tests for possible liver metastases, etc.). No test is however 100% accurate, so even with a positive result, this does not give a definitive diagnosis of cancer and hence other tests including scans (e.g. chest X-ray, CT scan, MRI scan, PET-CT scan, etc) and subsequent biopsies are often needed.
Whilst not quite clinical grade yet, new blood / urine testing for different types of cancer through measuring specific cancer biomarkers, DNA/RNA profiling and other novel strategies are being developed and should soon make its way into standard clinical practice; this is in addition to the advances in better imaging modalities (i.e. scans). Already, we are finding genotyping plays a significant role in determining the type of treatment one might initiate for certain forms of cancer such as lung cancer. Furthermore, advances in scientific and medical research have progressed to the unchartered territories of genetic manipulation and therapy (e.g. the use of CRISPR technique and Base Editors in the lab), stem cell therapy with the ability to generate any type of cells and the role of the gut microbiome in relation to our immune system to name but a few. All of these medical and technological advances will likely play a significant role in contributing to the treatment of cancer and may one day help to cure cancer.