Women who were diagnosed with endometrial cancer under the age of 50 had tumors with signs of Lynch syndrome in a significant number of cases. Lynch syndrome or hereditary non-polyposis colon cancer (HNPCC) greatly increases the lifetime risk of both colorectal and endometrial cancer.
Researchers in Australia studied tumors from 146 women who were diagnosed with endometrial cancer before the age of 51. They stained the tumor sections for proteins expression by mismatch repair genes, a genetic mutation that leads to Lynch syndrome cancers. They also tested tumor DNA for other changes that can identify or exclude Lynch syndrome, and reviewed family medical history where it was available.
They found 26 tumors that were presumed to be due to Lynch syndrome or 18 percent of all the early endometrial cancers. The tumors were more likely to be poorly differentiated, stage II, have rapidly dividing cells, and invade the wall of the uterus more deeply.
Patients with the presumptive Lynch syndrome tumors were also more likely to have a family history of cancer, Lynch associated cancer in a first-degree relative, or family colon cancer histories that met the Amsterdam criteria for Lynch syndrome.
The research team concluded that endometrial cancers diagnosed in women fifty or younger should be routinely tested by immunohistochemistry for proteins associated with Lynch syndrome.
Michael Walsh and his colleagues wrote,
Presumptive Lynch syndrome was identified in 18% of early-onset endometrial cancer. A risk of this magnitude would argue for routine immunohistochemical testing of tumors in patients diagnosed with EC at or before the age of 50 years.
SOURCE: Walsh et al., Clinical Cancer Research, March 15, 2008.