About 1 in every 7 men will be diagnosed with prostate cancer during his lifetime. Prostate cancer is more common in older men than younger men. The median age at diagnosis being 66. Men with a family history of prostate cancer are more likely to be diagnosed with the disease.
ANGLE is currently working with researchers to prove that characterization of rare cells can be more predictive than Gleeson score.
ANGLE’s work with Barts Cancer Institute
Using the Parsortix system, Barts Cancer Institute (BCI) researchers were able to successfully harvest CTCs from 100% of the patients in a 52 patient pilot study. The Parsortix system harvested a range of different circulating cells comprising not only CK+ cells (epithelial cells), which can be captured using traditional antibody-based capture systems, but also CKVimentin+ cells (mesenchymal cells).
Barts patient data suggests that the Parsortix system may be used both to detect prostate cancer and to assess its aggressiveness, all through a simple blood test. This is crucial because it means that men with low level disease could avoid unnecessary and potentially harmful solid biopsy and surgical
intervention instead having “active surveillance”, whereas men with an aggressive form of disease could be fast-tracked for further investigation and treatment. The current gold standard for detection is the prostate-specific antigen (PSA) blood test, which is known to have low sensitivity and low specificity (i.e. high levels of false positives) and the digital rectal exam (DRE – which is less effective than the PSA test). Where the PSA level is high or the DRE indicates an enlarged prostate, a solid prostate biopsy will be undertaken to detect cancer and assess the aggressiveness of the disease. This process results in many men having invasive biopsies unnecessarily.
Key conclusions from the later BCI work include the following:
- The Parsortix system detected CTCs in 100% of the metastatic prostate cancer patients
- The patients with localised disease included patients with early stage disease (determined by clinical investigation including the Gleason score of solid tissues taken through invasive procedures), where the decision had been taken that “active surveillance” was appropriate rather than medical intervention. Even for these earliest stage, indolent cancer patients, the Parsortix system harvested CTCs that could be detected in 75% of these patients
- The Gleason score is currently the best parameter for assessing aggressiveness of prostate cancer involving pathologist assessment of the morphology of the cells obtained from the solid biopsy. The number of mesenchymal CTCs harvested by the Parsortix system was compared to the Gleason score for each of the patients and there was found to be a good correlation suggesting that Parsortix liquid biopsy may be able to provide the same or similar information as the invasive solid biopsy in assessing the aggressiveness of the cancer
- The status of the patient – metastatic or localised – was analysed against the number of mesenchymal CTCs harvested by the Parsortix system. Separately the status of the patient – metastatic or localised – was analysed against the patient’s Gleason score. Comparison of the results suggests that the Parsortix system may be able to indicate the metastatic or localised status of the patient with a higher level of accuracy than the Gleason score