Despite the extensive information regarding hemophilia’s hemorrhagic complications, the literature on cancer in hemophilia is scarce, especially in pediatric patients. Many uncertainties remain concerning diagnosis and workup. We report a rare case of two severe diseases (neuroblastoma and hemophilia A (HA)) concomitantly present in the same pediatric patient. We highlight that the diagnosis of severe HA did not have a negative impact on the patient’s oncologic course. This case also illustrates the significance of the cooperation among different specialties and hospitals when caring for the same patient.

Severe combined immunodeficiency disorders (SCID) are a genetically heterogeneous group of inherited defects characterized by severe abnormalities of immune system development and function that lead to a wide spectrum in clinical manifestations. A subgroup of patients presents a disabling and life-threatening clinical course. In these cases, allogeneic hematopoietic stem cell transplant provides a curative approach. The occurrence of SCID-associated lymphoproliferative disorders is rare and occur mostly in adenosine deaminase-deficient severe combined immunodeficiency disorders, after allogeneic hematopoietic stem cell transplant. Epstein Barr virus infection is present in the majority of individuals with primary immunodeficiency developing lymphoma, revealing compromised anti-tumour surveillance of virally transformed cells. Herein, we report a rare case of diffuse large B cell lymphoma occurring in an Epstein Barr virus negative, non-transplanted X-linked severe combined immunodeficiency 4-months-old infant, successfully treated with immunotherapy and allogeneic stem cell transplantation. This case suggests that Epstein Barr virus -independent mechanism of neoplastic transformation must take action in severe combined immunodeficiency associated lymphoma and unveils the curative potential of donor T cells after allogeneic transplantation.