For smaller groups of patients, healthcare can already offer treatment that is directly targeted at molecular changes that drive the growth of cancer cells. This is called precision medicine. However, broader and more comprehensive molecular diagnostics need to be developed and implemented. This will enable more cancer patients to benefit from the progress that has been made in cancer research in the last decade.
Our diagnostic challenge
Each year over 60,000 new cases of cancer are diagnosed in Sweden. Cancer is the most common cause of death in Sweden amongst those under the age of 80, resulting in 20,000 deaths each year. Solid tumours constitute over 90 percent of all cancers, while other cancers occur in the blood forming organs (see more under hematology). Cancer is a disease group with a large degree of variation. The basic disease mechanisms are different for different organs, for example for breast cancer compared to lung cancer. Since a cancer also develops from the body’s own cells, each patient has a unique “fingerprint” which requires unique treatment that is adjusted to the individual. The fingerprint is the specific set of hundreds of gene changes (mutations) that have occurred in the cancer cell’s genetic material (DNA) while the cancer has developed. This may have been going on for 20 years before a tumour is discovered.
The current situation
Genetic testing is currently performed for a handful of genetic mutations which indicate that the tumour may respond to a targeted treatment for these mutations. This type of testing is primarily conducted within lung cancer, colorectal cancer and skin cancer (malignant melanoma) where precision drugs, targeted treatments that are active against specific molecular changes, are standard therapy in healthcare. The analyses take place at the molecular-pathological laboratories in Sweden and are performed on tissue samples (biopsies) that are sent for cancer diagnostics to a pathology department. Today’s genetic testing manages to detect changes in 1-50 cancer genes through “targeted” sequencing. However, we can see that there is an increased need to analyse mutations in approximately 500 cancer genes in order to cover all relevant gene changes in all the different forms of cancer.
Goals for development:
- Develop, and implement in clinical routine, targeted diagnostics for mutations in approximately 500 genes that are relevant to the development of cancer and choice of treatment.
- Develop, and implement in clinical routine, equivalent diagnostics for blood samples. Since cancer cells are continually replaced, cancer-cell DNA leaks out into the blood. Sampling can be made easier with a blood sample instead of a tissue sample in order to find a mutation.
- Pilot project for global diagnostics of whole genome (DNA) and gene expression (RNA) in cancer cells – in other words mapping mutations in all 20,000 genes in a patient’s genetic material.
- Establish national standardised tools for analysis, communication channels and clinical practice, together with physicians, for standardised diagnostics and treatment in Sweden.
National collaboration in Genomic Medicine Sweden will be intensified in the development, validation and implementation of new analyses and within ongoing diagnostics. In parallel with this, work in regional GMCs is being developed, where molecular pathology units work side by side with all of the specialties that are needed to treat patients with cancer.