A study examines whether computer-assisted detection on mammography provides sufficient benefit for the cost. Plus: Do first-time pregnancy cesarean deliveries increase the preterm birth in subsequent pregnancies. And, is conventional wisdom surrounding pregnancy and cancer accurate?
According to a study in JAMA Internal Medicine, interpretation of mammograms with computer-aided detection (CAD) may be no better than without use of the technology. CAD is used for most screening mammograms in the United States at a cost of $400 million a year.
Researchers compared the accuracy of digital screening mammography that was interpreted with (n =495,818) versus without (n = 129,807) CAD from 2003 to 2009 among 323,973 women. The mammograms were interpreted by 271 radiologists across 66 facilities in the Breast Cancer Surveillance Consortium. Linking with tumor registries identified 3159 breast cancers in the women within 1 year of the screening.
Computer-aided detection did not improve screening performance by any assessed metric. Mammography sensitivity was 85.3% (95% CI, 83.6%-86.9%) with and 87.3% (95% CI, 84.5%-89.7%) without CAD. Specificity was 91.6% (95% CI, 91.0%-92.2%) with and 91.4% (95% CI, 90.6%-92.0%) without CAD. No difference was seen in the cancer detection rate (4.1 in 1000 women screened with and without CAD). Intraradiologist performance was not improved with CAD. Overall sensitivity was significantly decreased for mammograms interpreted with versus without CAD in the subset of radiologists who interpreted mammograms both with and without CAD (odds ratio, 0.53; 95% CI, 0.29-0.97).
The investigators concluded that CAD showed no improved diagnostic accuracy versus the traditional mammogram, suggesting that insurers are paying more for CAD, even though CAD provides no established benefit.
First-pregnancy cesarean ups risk for preterm birth later
A new study supported by the National Institutes of Health points to an increased risk of preterm delivery in subsequent pregnancies in women who deliver their first pregnancy via cesarean section. The findings, from a case-report analysis, were published in BJOG.
Researchers from the University of Utah and Intermountain Health Care compared women who had delivered their first pregnancy at term and their second preterm (≥2000/7 to <370/7 weeks) with women who had term births in their first two pregnancies. The final cohort comprised 35,983 women, of whom 1353 (3.8%) had a term delivery followed by a preterm delivery. Cases and controls were similar with regard to race/ethnicity and maternal age at the time of first and second deliveries.
The main outcome measure for the study was risk factors for the term-preterm sequence. The authors looked at social factors that had the potential to change between a woman’s first and second pregnancies and compared intrapartum labor characteristics in the first pregnancy in the cases and the controls.
Women with term births followed by preterm births delivered their second pregnancy approximately 3 weeks earlier (35.7 versus 39.1, P<0.001). Multivariable models that accounted for known risk factors for preterm birth showed that women who delivered their first pregnancy by cesarean (adjusted odds ratio [aOR]=2.20; 95% confidence interval [CI] 1.57-3.08), had new tobacco use (aOR=2.33; 95% CI 1.61-3.38), and an interpregnancy interval <18 months (aOR=1.37; 95% CI 1.21-1.55) were at increased risk of having a term pregnancy followed by a preterm delivery.
The authors concluded that cesarean delivery of a first pregnancy is a significant risk factor for preterm birth following a term delivery and that women should receive postpartum counselling about an appropriate interpregnancy interval and cessation of use of tobacco.
Challenging beliefs about cancer in pregnancy
The traditional belief that maternal cancer treatment during gestation leads to impairment in offspring may not be entirely accurate. According to a multicenter case-control study in New England Journal of Medicine, second-trimester or later exposure to chemotherapy or radiation may increase risk of prematurity but it is not necessarily a reason to terminate pregnancy.
The study was a collaboration between centers in Belgium, the Netherlands, Italy, and the Czech Republic with case children born to mothers who were diagnosed with cancer during pregnancy and control children born to healthy mothers with uncomplicated pregnancies and deliveries. Obstetric, perinatal, and oncologic data wereas collected for each mother-child pair. Fetal radiation doses were calculated using the dose program Peridose. From 2005 to 2011 the case and control pairs were invited to follow up at 18 months and from 2012 to 2015 the children from both groups were invited to follow up at 18 and 36 months. For children who had follow-up at both 18 and 36 months, only one result was included in the analysis.
In the case group, there were 129 children (median age 22 months; range 12 to 42 months). During pregnancy, 96 of the children (74.4%) were exposed to chemotherapy alone or in combination with other treatments; 11 (8.5%), to radiotherapy either alone or in combination; 13 (10.1%), to surgery alone; 2 (1.6%), to other forms of drug treatment; and 14 (10.9%) were exposed to no treatment.
Birth weight below the 10th percentile was seen in 22% of the children who were prenatally exposed to cancer treatments versus 15.2% in the control group (P = 0.16). No significant different was seen between the groups regarding cognitive development using the Bayley score (P = 0.08) or in subgroup analyses. Cardiologic evaluation among 47 children at 36 months showed normal cardiac findings.
The investigators concluded that prenatal exposure to cancer either with or without treatment was not found to impair cognitive, cardiac, or general development of children in early childhood. Premature birth was associated with worse cognitive outcome, but this was independent of cancer treatment.