In JAMA this week, researchers from the US and Canada present findings from a study of the effects of screening for ovarian cancer on mortality rates for the disease. The team conducted a randomized control trial of 78,216 women who were assigned to undergo either annual screening for ovarian cancer or usual medical care. The intervention group was offered annual screening with cancer antigen-125 for six years and transvaginal ultrasound for four years. Ovarian cancer was diagnosed in 212 women in the intervention group and in 176 women in the control group, and there were 118 deaths caused by ovarian cancer in the intervention group and 100 in the control group. "Among women in the general US population, simultaneous screening with CA-125 and transvaginal ultrasound compared with usual care did not reduce ovarian cancer mortality," the authors write. "Diagnostic evaluation following a false-positive screening test result was associated with complications."
Also in JAMA this week, researchers in the UK explore the long-term risks of subsequent primary neoplasms — abnormal proliferations of cells that might be indicative of cancer — in childhood cancer survivors. The authors studied a cohort of 17,981 five-year survivors who had been diagnosed with cancer when they were younger than 15 years, and ascertained 1,354 subsequent primary neoplasms in a median follow-up time of 24.3 years. The most frequent were central nervous system, non-melanoma skin cancer, digestive, genitourinary, breast, and bone neoplasms, the authors report.
And finally in JAMA, researchers in France present a study on secondary cancer risks associated with germline mutations of the MLH1, MSH2, and MSH6 genes in people with Lynch syndrome, a form of colorectal cancer. The researchers analyzed families with Lynch syndrome and found significant differences in estimated cumulative cancer risk between the three mutated genes. For the MLH1 mutation, the team estimated a patient's cumulative risk of secondary colorectal cancer by age 70 to be 41 percent, 48 percent for the MSH2 mutation, and 12 percent for the MSH6 mutation. For endometrial cancer, the risks were 54 percent, 21 percent and 16 percent, respectively, and for ovarian cancer, the risks were estimated at 20 percent, 24 percent, and 1 percent. "MSH6 mutations are associated with markedly lower cancer risks than MLH1 or MSH2 mutations. Lifetime ovarian and endometrial cancer risks associated with MLH1 or MSH2 mutations were high but do not increase appreciably until after the age of 40 years," the authors write.