The repercussions of overturning Roe v. Wade — and the failure of the Supreme Court to provide any guidance on exceptions related to the life and health of the mother — are potentially catastrophic for a subset of women who face a life-threatening diagnosis of pregnancy associated cancers (PAC).

In their perspective article, publishing in JAMA Oncology on Aug. 11, 2022, Katherine Van Loon, MD, and Jordyn Silverstein, MD, from University of California, San Francisco discuss the unique challenges PAC poses for women and their care teams, who must balance both safety of the mother and that of the fetus or embryo.

Approximately 1 in 1,000 pregnancies are affected by a concurrent cancer diagnosis. The most common cancers include breast cancer, cervical cancer, lymphoma, ovarian cancer, leukemia, colorectal cancer and melanoma. Termination of the pregnancy occurs in 9% to 28% of cases, with many occurring in the first trimester.

For women with a cancer diagnosis during pregnancy, many factors influence the decision-making to terminate a pregnancy, including:

  1. The mother’s diagnosis, stage, and prognosis

Prognosis is closely tied to the cancer type, tumor biology, and stage at diagnosis. Some studies suggest that pregnancy itself is not associated with worse cancer survival compared with non-pregnant women. However, in some cancers, the hormones of pregnancy may accelerate disease progression.

  1. The gestational age of the embryo or fetus

The gestational age of the embryo or fetus is a critical factor in the context of evolving state laws governing access to pregnancy termination at different time points.

  1. The recommended therapeutic plan

Oncologists should discuss ideal treatment plans and how modifications for pregnancy are likely to influence prognosis for the mother and risks to the fetus. Limited safety data for most anticancer therapies on the fetus are based on case reports or other small studies.

  1. The mother’s personal values and beliefs

Complex medical decisions are often influenced by religious and/or cultural beliefs, as well as by individual, family, and community factors and by trust (or lack thereof) in the health care team.

“Restrictions on pregnancy termination will primarily impact cases in which oncologic therapy is urgently needed but contraindicated in pregnancy, and the fetus is not yet viable,” writes senior author Van Loon, UCSF associate professor of clinical medicine and director of the UCSF Global Cancer Program with the UCSF Helen Diller Family Comprehensive Cancer Center.

“Determinations of whether a termination can occur in a medical emergency, or with a life-threatening physical condition, will be determined by individual state laws. Oncologists who provide care in states with laws in place restricting abortion access will find themselves in precarious situations, in terms of navigating recommendations for termination based upon medical indication.”

In 2020, there were a total of 3.6 million births in the United States, and 1.5 million of them (41%) were in the 26 states that will likely ban abortions. The authors estimate that at least 1,500 women will be diagnosed with PAC in the next year in states that will impose restrictions on the right to terminate a pregnancy. Based upon the occurrence rate and estimated rates of termination, they project that between 135 and 420 women with PAC will face compromises in their cancer care and potential loss of life.

Because of the complexity and multidisciplinary nature of cancer treatment during pregnancy, the authors note that the Supreme Court decision will impact oncologists’ ability to deliver optimal care in these complex cases. Particularly in cases in which the fetus is considered viable but still pre-term and therapy for the mother cannot be safely administered during pregnancy, physicians will have to balance risks of pre-term delivery versus risks of delayed cancer treatment for the mother.

“If a woman needs oncologic therapy to save her own life, physicians should not be criminalized for a decision to provide her with the best possible care,” said Van Loon.

This article was originally published August 11, 2022, by the University of California, San Francisco News Center. It is republished with permission.