Evaluating the benefits of surveillance for cancer prevention in healthy patients with Lynch syndrome

The present study evaluated the benefits of surveillance in preventing colorectal cancer (CRC) and endometrial cancer (EC) in healthy individuals with Lynch syndrome. 

Lynch syndrome is an inherited condition that predisposes patients to cancer of the large intestine (CRC). Lynch syndrome can also cause cancers of the uterine muscle (endometrial cancer), ovaries, stomach and other organs. The disease is caused by a defective gene (mutation) that can be inherited in an autosomal dominant pattern. This means that if one patient carries the mutation, there is a 50% chance that mutation will be passed on to each child. However, relatives of Lynch syndrome patients have the possibility to be tested for these mutations, thus preventing some of the cancers by regular check-ups. For the affected individuals surveillance can be done by colonoscopy (a procedure doctors use to look inside the large intestine using a thin flexible tube with a camera called a colonoscope) for CRC and ultrasonography for the uterus and ovaries. 

The study included 57 families of Lynch syndrome affected individuals and 629 healthy members of these families were tested for the disease. Mutations were found in 246 relatives (mutation-positive), whereas in 383 the test was negative (mutation-negative). The mutation-positive participants underwent periodical colonoscopies (at maximum 3 years interval) and women also had ultrasonography of the uterus and a sample of uterine muscle tissue (biopsy). 

In conclusion, in this study, despite the highly increased risk of getting cancer for patients who tested positive for Lynch syndrome mutations, there was no reduced survival rate compared to mutation-negative patients.

This study is proof that surveillance is critical for preventing cancers in Lynch syndrome mutation carriers. When found early cancer is easy to treat, thus increasing the chance for long-term survival. Still, more frequent colonoscopies (at maximum 2 to 3-year interval) are recommended in order to detect CRC in earlier stages.