SAN ANTONIO — New research provides some reassuring news for young women hoping to become pregnant after a diagnosis of BRCA-mutated breast cancer.
said Jame Abraham, MD, chair of Hematology & Medical Oncology at the Cleveland Clinic, who was not involved in the research.
The analysis, presented at the San Antonio Breast Cancer Symposium, revealed no issue with women becoming pregnant and carrying a healthy baby to term and reported no sign of worse disease outcomes among BRCA carriers following diagnosis and treatment.
“The final and most important conclusion from our study is that conceiving after proper breast cancer treatment and follow-up should not be contraindicated anymore in young BRCA carriers,” a message of particular importance for oncofertility counseling, lead investigator Matteo Lambertini, MD, a breast cancer oncologist at the University of Genova, Italy, said during his SABCS presentation.
The study was published December 7 in JAMA to coincide with his presentation.
Although pregnancy after breast cancer is generally considered safe, limited data exist for BRCA carriers in particular, Dr. Lambertini said.
The current analysis represents the largest look into the matter to date. The study included 4732 young women from across the globe who had been diagnosed with stage I-III invasive breast cancer. These women, all BRCA carriers, were 40 years or younger (median age at diagnosis, 35 years).
The team compared outcomes between 659 patients who had at least one pregnancy over a median follow-up of almost 8 years with 4073 women who did not become pregnant.
Dr. Lambertini and colleagues reported a median time of 3.5 years from breast cancer diagnosis to conception. Overall, about 1 in 5 young BRCA carriers (22%) conceived within 10 years after their breast cancer diagnosis. Of the 80% of patients with a completed pregnancy, 91% delivered at term and only 4 infants (0.9%) had documented congenital anomalies.
In short, “the rate of pregnancy, fetal, and obstetric complications was low and in line with the expectations in a population of women with similar age and no history of breast cancer,” Dr. Lambertini said. The team cautioned, however, that the data was extracted from oncology medical records, which might have underreported maternal and fetal outcomes.
Disease-free survival was similar among women who became pregnant and those who did not after breast cancer (adjusted HR, 0.99; 95% CI, 0.81-1.20).
When looking at the specific BRCA gene, differences did emerge. BRCA1 carriers had better disease-free survival after pregnancy (aHR, 0.80), while BRCA2 carriers appeared to have worse disease-free survival after pregnancy (aHR, 1.55).
For reasons that remain unclear, the researchers also found that BRCA1 carriers who got pregnant had significantly better breast cancer-specific survival (aHR, 0.59; P < .01) and overall survival (aHR, 0.58; P < .01). These women tended to have HR-negative breast cancer, which the authors also found was associated with improved survival after pregnancy (aHR, 0.76).
It’s possible, the team posited, that hormone receptor status played a role in the observed survival benefit. It’s also possible that these women were healthier overall.
The overall survival advantage, however, did not extend to BRCA2 carriers, who tended to have hormone receptor-positive disease. Hormone receptor-positive status did not appear to have a significant impact on survival (aHR, 1.30; 95% CI, 0.95-1.76).
“While the results appear reassuring for BRCA1 carriers, more caution is needed to counsel BRCA2 carriers, “ the investigators wrote.
The study was funded by the Italian Association for Cancer Research, Gilead, and others. Investigators had numerous ties to industry, including Dr. Lambertini, who is an adviser and speaker for Roche, Pfizer, Novartis, and others. The full list of disclosures can be found with the original article.
A version of this article appeared on Medscape.com.