Hemophagocytic syndrome caused by Epstein–Barr virus and cytomegalovirus infection during neoadjuvant chemoradiotherapy for rectal cancer: a case report

Background: Immune dysregulation and excessive inflammatory responses can lead to hemophagocytic syndrome (HPS) involving autologous blood cell phagocytosis, with fatal outcomes occurring in some cases. This case report describes an 80-year-old man who was simultaneously diagnosed with diffuse large B-cell lymphoma (DLBCL) and rectal cancer and developed HPS during neoadjuvant chemotherapy for the latter. Case description: Treatment for DLBCL was initiated first, and six courses of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy were administered, which led to a clinical complete response of the lymphoma lesions. Following the completion of DLBCL treatment, preoperative chemoradiotherapy with tegafur-uracil/leucovorin (UFT/UZEL) was initiated for rectal cancer. On Day 18, a fever of 38.3 °C developed. Blood tests conducted on Day 24 revealed Grade 4 neutropenia and Grade 4 thrombocytopenia. Granulocyte colony-stimulating factor (G-CSF) preparation, antibiotic therapy, and recombinant human soluble thrombomodulin (rTM) were initiated as disseminated intravascular coagulopathy (DIC) therapy. A poor therapeutic response was achieved, and acute respiratory distress syndrome (ARDS) developed on Day 34. Imaging of the biopsied bone marrow confirmed that hemophagocytosis by macrophages was occurring. The patient was ultimately diagnosed with HPS. Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infections were identified, and treatment to combat the infections was initiated; however, the patient passed away on Day 37. Conclusion: It is important to consider the possibility of HPS, and diagnosis and treatment initiation should occur in a timely manner when fever of an unknown origin and decreased blood cell counts are observed during malignant disease treatment.