The primary enthusiasts were Professor of Oncology Håkan Olsson and Reader in Clinical Genetics Ulf Kristoffersson. At an anniversary symposium on the development of cancer genetics, Håkan Olsson talked about the situation in the past:
“A cancer patient’s family history was often not considered. If it was, they only looked at immediate relatives, and only at the same type of cancer.”
Today we know more: the entire family tree contains important information and different types of cancer can have the same hereditary foundation. There is a link between breast cancer and ovarian cancer, for example, and between female genital cancers and bowel cancer.
Lund was the second place in Sweden to have a clinical cancer genetics clinic. Around 300 families or individuals attend each year, both referrals and healthy individuals who suspect that cancer runs in their family. At the clinic, a family tree is drawn up with details of which relatives have had cancer, the risk is assessed and, if appropriate, a genetic test is performed.
If the investigation shows a genetic change with an increased risk of cancer, preventive measures may be carried out such as regular checks or an operation to remove breasts or ovaries. These ideas were very controversial 20 years ago.
“Many doctors thought we were exaggerating when we recommended that certain women went for more regular checks”, said Ulf Kristoffersson.
“Not to mention preventive operations... I was almost booed off stage once when I spoke about removing the ovaries of young women with a high hereditary risk of ovarian cancer. However, we now know that removing the organ where the cancer originates provides effective protection against hereditary cancer, even if a balance has to be struck against performing the operation too early.”
More than 100 mutated genes that can cause cancer have been identified so far. The most well-known are the two breast cancer genes that were found back in the 1990s, but there are also genes that can cause hereditary colorectal cancer, malignant melanoma and prostate cancer. There are also situations where multiple genes, which individually have little effect on the risk of developing cancer, combined increase (or reduce) the cancer risk.
From the field of cancer, genetic advice is spreading to other areas. The genetics clinic gives advice in collaboration with the cardiologists at Skåne University Hospital on the hereditary background to ‘sudden death’ from heart disease. Activities focusing on early dementia are also under discussion.
The symposium was about the historical situation, the current situation and future activities in the area. Should genetic tests be centralised to one central and efficient lab for the whole of Europe, or will the equipment become so cheap that every clinic can have it? Who will interpret the results of all these genetic tests – should GPs learn more about clinical genetics or should there also be genetics specialists at every clinic? There were more questions than answers, and the answers may not be found for another 20 years.
Ingela Björck
ABOUT CANCER GENETICS
More than one in three people in Sweden will be diagnosed with cancer during their lifetime. Known genetic changes cause 5–10 per cent of all cancer cases. Other, as yet unmapped genetic changes are believed to be responsible for a further quarter of all cancers.
