Hello Health Rounds readers! Today we feature an analysis that suggests a test used to assess the need for chemotherapy for a type of breast cancer may be ruling out young Black women who could have benefited from the treatment. Another study found how fasting helps reduce inflammation in the body that can be associated with serious health conditions. We also highlight a study that may advance understanding of a life-threatening complication of pregnancy.
Philips‘ U.S. sales of sleep apnea devices face years-long halt after FDA deal.
A newly published analysis upends traditional theories of why the placenta sometimes does not separate from the uterus at birth, in a life-threatening complication known as placenta acreta. Scroll down to read about the new findings. REUTERS/Regis Duvignau
Test may underestimate chemotherapy benefit for Black women
A common test may advise against use of breast cancer chemotherapy in young Black women who would have benefited from the treatment, according to findings from a large study.
The “21-gene breast recurrence score” is used to identify early-stage estrogen receptor-positive breast cancers that are likely to be aggressive and thus should be treated with chemotherapy.
Researchers analyzed treatment and outcomes in more than 70,000 U.S. women with such cancers.
Overall, the study validated the tool for identifying non-Hispanic Black, Hispanic, and non-Hispanic white women with ER-positive breast cancer and negative lymph nodes for whom chemotherapy would be appropriate, researchers reported in the Journal of the National Comprehensive Cancer Network.
They did not find the tool to be accurate in Asian/Pacific Islander women.
In a subsequent analysis that was not planned in advance – and which therefore needs to be repeated in future studies – the researchers found the test may underestimate the benefit of chemotherapy for young non-Hispanic Black women.
Almost all patients with this type of cancer receive estrogen-blocking pills, whether or not they get chemotherapy.
But Black women’s tumors are less likely to respond to estrogen-blocking pills than those in other women, and tumors in young women are likely to be more aggressive. So it might be that chemotherapy makes more of a difference for young Black women, according to the report.
The threshold for recommending chemotherapy may therefore need to be lower in these women, the researchers said.
“It may be inappropriate for doctors to use exact cutoffs and tests regardless of race or ethnicity because there are underlying differences in biology,” study leader Dr. Kent Hoskins of the University of Illinois Cancer Center said in a statement.
Skipping meals may help fight chronic inflammation
Fasting helps reduce chronic inflammation in the body, and UK researchers say they may have discovered how that happens.
Going without food for an extended period raises blood levels of a lipid known as arachidonic acid that inhibits inflammation, they found.
The researchers analyzed blood samples from 21 volunteers who fasted for 24 hours. Restricting calorie intake resulted in increased levels of arachidonic acid, according to a paper published in Cell Reports.
When the researchers studied arachidonic acid’s effect in immune cells cultured in the lab, they found it reduces the activity of a component of the inflammatory process known as the NLRP3 inflammasome, which is known to be a factor in diseases such as obesity, atherosclerosis, Alzheimer’s and Parkinson’s disease.
Inflammasomes are multiprotein complexes that form in response to injury or infection or exposure to toxins. They act like alarms inside of cells, triggering the release of inflammatory proteins called cytokines, the researchers explained.
“It’s too early to say whether fasting protects against diseases like Alzheimer’s and Parkinson’s disease as the effects of arachidonic acid are only short-lived, but our work adds to a growing amount of scientific literature that points to the health benefits of calorie restriction,” study leader Clare Bryant from the University of Cambridge said in a statement.
“It suggests that regular fasting over a long period could help reduce the chronic inflammation we associate with these conditions.”
Clues help explain life-threatening pregnancy complication
A new analysis upends traditional theories of why the placenta sometimes does not separate from the uterus at birth, a life-threatening complication that affects four million deliveries each year in the United States alone.
Typically, the placenta detaches from the uterine wall after childbirth and is delivered shortly after the baby emerges. In placenta accreta, the placenta grows too deeply into the wall of the uterus and part or all of it remains attached, resulting in hemorrhage and often in emergency hysterectomy.
It was previously thought that in cases of placenta accreta, placental cells called trophoblasts invade the uterus and keep the connection intact. The new study revealed important genetic and cellular changes inside the decidua – the layer of the uterine lining that forms during pregnancy to embrace and protect the embyro.
In cases of placenta accreta, normal boundary limits between the cells of the uterine lining and the growing placental blood vessels are lost, and the placenta ends up being attached too tightly, the researchers said.
For the new study, published on Monday in the American Journal of Obstetrics & Gynecology, researchers analyzed more than 31,000 individual cells obtained from 12 placentas – six with placenta accreta and six without. They also measured and mapped gene activity in tissue samples from the placentas.
“Our goal was to characterize the intimate relationship between the maternal and fetal tissue at the site of accreta or malfunction,” study leader Dr. Yalda Afshar of the David Geffen School of Medicine at UCLA said in a statement.
“The genes and signaling pathways we identified go beyond providing a better understanding of the mechanism of the disease; they may be used as targets to help us refine diagnostic tests, track disease progression over time, and discover new, more effective therapies.”