Unlocking the Treatment Challenges of Diffuse Large B-Cell Lymphoma in the Third Trimester of Pregnancy: A Case Report

Superando los desafíos del tratamiento del linfoma difuso de células B grandes en el tercer trimestre del embarazo: Informe de un caso

Abstract

A 24-year-old woman in her third trimester of pregnancy presented with a progressively enlarging mass in the posterior thigh. Histopathological examination from incisional biopsy, followed by immunohistochemistry demonstrated diffuse large B-cell lymphoma, germinal center B-cell subtype. Staging MRI at 30 weeks’ gestation revealed extensive disease involving the popliteal fossa, inguinal nodes, parailiacal nodes, and bone marrow replacement of the femur, consistent with stage IIB disease. Following multidisciplinary discussion, chemotherapy with R-CHOP was initiated at 30 weeks and was well tolerated. At 36–37 weeks, she developed premature rupture of membranes and delivered a healthy late-preterm infant vaginally. Chemotherapy was resumed postpartum with continuation of R-CHOP until the 6^th cycle. This case highlights the challenges of diagnosing lymphoma during pregnancy, as symptoms may mimic physiological changes, and the therapeutic dilemmas of balancing maternal disease control with fetal safety. MRI provided safe and effective disease staging, while timely biopsy and immunophenotyping were crucial for accurate diagnosis. Administration of chemotherapy during the third trimester was feasible and allowed maternal treatment without compromising neonatal outcome. This report underscores the importance of multidisciplinary coordination, supportive care, and reproductive counseling in the management of aggressive lymphoma during pregnancy.