Successful pregnancy and fetal outcome following previous treatment with pembrolizumab for relapsed Hodgkin's lymphoma

BACKGROUND: Classical Hodgkin lymphoma (cHL) is one of the most frequently diagnosed neoplasms in young adults and is curable even in the relapse setting. Many patients seek advice regarding pregnancy once they have a sustained complete remission (CR). PD1 inhibitors are effective in inducing CRs in relapsed cHL, but little is known about their effects on pregnancy, fetal outcomes, or risk of relapse. The PD1/PDL1 axis is vital in the maintenance of pregnancy, allowing for fetal tolerance. This axis is also a key pathway by which Hodgkin Reed Sternberg cells escape immune surveillance. Thus, exposure to PD1 inhibitors in the context of a pregnant cHL survivor could potentially lead to maternal and fetal complications as well as increase the risk of relapse. Pregnancy and fetal outcomes following PD1 inhibitors have been reported in women with melanoma, but not cHL. Such data may help physicians counsel their patients on this topic. CASE: This case describes a 25‐year‐old woman who was diagnosed with advanced stage cHL that was treated with multiple courses of chemotherapy and autologous stem cell transplant (ASCT) for primary refractory disease. She experienced a relapse eight months following ASCT and was treated with the PD1 inhibitor pembrolizumab. She completed a total of 21 cycles, achieving a CR after cycle five. After 2 years of sustained CR off pembrolizumab, she had an unassisted and uneventful pregnancy. She delivered a healthy baby boy with no significant complications. He reached his normal milestones in his first year. She remains in CR four years following her last dose of pembrolizumab, evoking the possibility of her being cured of cHL. CONCLUSION: Successful pregnancies and fetal outcomes, while maintaining clinical remissions, are possible in women with relapsed cHL treated with pembrolizumab.