December 21, 2012 | 2 minute read

In a finding that underscores the importance of making lifestyle choices that can reduce cancer risk, a large new study now suggests that even when parents are diagnosed with a cancer at an older age the child is still at increased risk of that cancer.

The paper is published online today at BMJ.

We focus on preventing cancer here but there are factors that increase our risk of cancer none of us can avoid, such as our age and our genes. For many cancers, having a parent diagnosed with that cancer increases the cancer risk for the child.

For this study, the researchers pulled information from a Swedish database that includes over 8 million Swedes born after 1931 and their parents. They looked at cancer diagnosis of parents and their children, from newborns to ages 76, and from the years 1961 to 2008.

There was no limit to the parents’ age. The highest risk for the children was seen in cases whose parents were diagnosed at earlier ages. Yet even when a parent was age 80 and older when diagnosed with cancer, the risk of the child getting that same cancer was higher compared to a parent without cancer. The majority of parents were diagnosed when they were ages 69 or older.

BMJ 2012;345:e8076

Compared to the parent without cancer, a child whose parent was diagnosed with cancer had a 6 percent increased risk for colorectal cancer; 9 percent increased risk for breast cancer, and 30 percent increased risk for prostate cancer.

When a parent was diagnosed at ages 90 and older, the risk of his/her child getting that same cancer was still increased for skin squamous cell carcinoma, colorectal, breast, and prostate cancer.

The authors took into account several known risk factors, including age, sex, and alcohol consumption. Family members might benefit from knowing this risk by avoiding known modifiable risks factor for that particular cancer and considering other preventive measures, the authors concluded.

Not smoking is one of the best steps you can take to reduce the risk of cancer but AICR’s reports have found that our weight, diet, and activity also play a role in cancer risk. You can look at the risk factors linked to each cancer site here.