Pregnancy Does Not Trigger Relapse in Hodgkin Lymphoma Survivors

“Caroline

Caroline Weibull, MSc

The incidence of Hodgkin lymphoma (HL) in women typically precedes and covers prime childbearing years, but a new study has found that pregnancy does not increase the risk of relapse among women in remission.

Researchers reviewed healthcare registries and medical records from Swedish Cancer Register to evaluate 449 women diagnosed with HL between 1992 and 2009. The women were between ages 18 and 40 at diagnosis.

Follow-up began 6 months after diagnosis, when the disease was assumed to be in remission.

Of the 449 women, 144 (32%) became pregnant during the follow-up period, but only one experienced a pregnancy-associated relapse, which researchers defined as a relapse during pregnancy or within 5 years after delivery.

Among the women who did not become pregnant during the follow-up period, 46 had a relapse.

“Based on these findings, we see no evidence that Hodgkin lymphoma survivors who become pregnant are at higher risk for relapse,” lead author Caroline Weibull, MSc, a biostatistician and doctoral student, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet in Stockholm, Sweden, said in a statement.

The population-based study, published in the Journal of Clinical Oncology, is the first large study to specifically examine whether pregnancy is a potential trigger for relapse of HL, according to the authors. The findings are consistent with previous, smaller studies.

The study also found that most of the relapses occurred shortly after diagnosis, while most pregnancies occurred later.

One possible theory to explain the lack of relapses in pregnant women in remission is the “healthy-mother effect,” meaning that women with less severe disease are more likely to become pregnant after diagnosis because they are at lower risk of relapse.

However, the authors noted that they found no evidence of the “healthy-mother effect” in their study.

“After accounting for difference in age and disease severity, we found that the probability of becoming pregnant did not differ markedly between patients with advance and early-stage disease or between patients who had different types of chemotherapy,” Weibull said.

Studies have shown that cancer survivors fear that pregnancy could promote a relapse, and because HL is the most common cancer in adolescents and young adults, many female survivors are of childbearing age.

“We conducted this study because Hodgkin lymphoma survivors, as well as clinicians, have expressed worries that pregnancy may increase the risk of relapse, despite a lack of empirical evidence to support such concerns,” co-author Ingrid Glimelius, MD, PhD, oncologist, Akademiska Hospital in Uppsala, Sweden and researcher affiliated with Uppsala University’s Department of Immunology, said in a statement.

“This rigorous study should help put those fears to rest.”

The authors conclude, however, that risk of relapse is highest in the first 2 to 3 years after diagnosis and, if possible, women should wait 2 years after finishing treatment before becoming pregnant.

Weibull CE, Eloranta S, Smedby KE, et al. Pregnancy and the risk of relapse in patients diagnosed with Hodgkin lymphoma [published online ahead of print December 14, 2015]. J Clin Oncol. doi: 10.1200/JCO.2015.63.3446