Scientists at Johns Hopkins University in Baltimore have developed a blood test for cancer detection. The test detects as many as eight cancers: ovaries, stomach, pancreas, esophagus, lungs, colon, breast and liver. This could be a breakthrough in cancer treatment, as researchers hope the test will detect most cancers at an early stage – when the chances of a cure are greatest.
Cancer cells leave traces of mutant genetic material and protein molecules in the bloodstream. A test called CancerSEEK detects mutations in 16 genes that are common in cancer, and in eight proteins.
According to specialists, if in the future it is possible to create a universal test that detects more DNA and protein mutations, it will allow to detect the majority of cancers at an early stage, which may be crucial for survival. In addition, it would not be necessary to perform massively unpleasant for the patient and costly for the health care system diagnostic procedures, such as colonoscopy. The cost of the CancerSEEK test is approximately $ 500 (approximately PLN 1700) per patient. Existing single-tumor tests tend to be much more expensive.
The test was tested on 1005 patients with cancers of the ovary, liver, stomach, pancreas, esophagus, colon, lung, or breast (in total, they account for 60% of cancer deaths in the US). The tumors have not metastasized yet. The test was 70% positive. cases.
The five cancers detected by the test (ovarian, liver, stomach, pancreas and esophagus) are not screened. Meanwhile, in their case, the test showed a sensitivity of 69 to 98 percent. – the latter value was for ovarian cancer. However, for breast cancer – which can be diagnosed by screening – it was only 33 percent.
The specificity was 99%. (only 1% of healthy controls “detected” non-existent neoplasm). In 83 percent patients, on the basis of the examination results, it was even possible to locate the tumor anatomically quite accurately.
A blood test performed once a year – like other periodic tests – could change the situation. This is especially true for pancreatic cancer, which is very symptomatic and detected so late that four out of five patients die within a year of diagnosis.
Further work is required to evaluate the effectiveness of the test in detecting early stages of cancer. The five-year study with the participation of 10 people has already started. people who were not previously diagnosed with cancer.