Background
Migration of Circulating Tumour Cells (CTC) into the bloodstream may be associated with early carcinogenesis, and can provide a biomarker for cancer progression and treatment effectiveness. An increase in CTCs in a patient’s bloodstream is associated with cancer progression, while a decrease in CTCs is associated with cancer containment or remission. Several technologies have been developed to identify CTC, including the isolation by filtration and analysis by microscopy using standard histo-pathological criteria.
Methods
The Isolation-by-Size-of-Epithelial-Tumour (ISET) technology (Rarecells, France) was established at NIIM to monitor treatment effectiveness in cancer patients and to screen for CTC in patients with a family history of cancer or clinical indication but no tumour mass. The ISET CTC has been validated in several studies and provides 100% specificity and 100% sensitivity.
Results
Between Sept-2014 and June-2015 we undertook 240 CTC tests, 93 (40%) were screening requests. CTC were detected in 43 (46%) of those patients screened, and follow-up tests including repeat CTC testing and scans were scheduled within 1-6 months of CTC results, in addition to lifestyle and nutritional advice provided. Repeat CTC testing of five patients revealed CTC reduction within an average of 5 months. In four patients with positive CTC counts and no detected tumour masses prior to CTC testing, follow-up scans revealed cancerous lesions in lung, breast (n=2), or prostate within 1, 2 or 6 months since CTC testing, respectively.
Conclusions
CTC screening provides a highly sensitive and specific tool for the early detection of patients at risk of developing cancer.