open access: Risk of breast cancer in Lynch syndrome: a systematic review

open access

Conclusion
 It is premature to provide a definitive answer to whether breast cancer is a Lynch syndrome ancer because of the following limitations. There is only one prospective study demonstrating an elevated risk of breast cancer in Lynch syndrome and further independent evidence is required to confirm the findings. Given the previous epidemiological studies used
different selection methods, subjects and statistical methods, a meta-analysis is not appropriate to generate a pooled estimate for breast cancer risk. Current evidence of the breast cancer risk is mainly from Caucasian populations and therefore may not be applicable
to the other ethnicities or populations, particularly given previous studies have demonstrated that risk of Lynch syndrome cancers vary across populations [77]. Given these limitations
and given breast cancer is relatively common disease in the general population, we recommend that studies to provide more precise estimate of risk will need to utilize large prospective cohort studies with a long follow-up. While current data is inconclusive at a population level, individual tumor testing results suggest that MMR deficiency is involved
with breast cancers in some individuals with Lynch syndrome.