[Uterine and ovarian relapse of acute lymphoblastic leukemia after transplantation: A case report]

Acute lymphoblastic leukemia (ALL) is a common type of acute leukemia and is essentially a malignant clonal proliferative disorder of hematopoietic stem cells. Currently, the widespread application of high-dose chemotherapy combined with allogeneic hematopoietic stem cell transplantation (allo-HSCT) has significantly improved patient survival and has become the most effective therapeutic strategy for ALL. However, relapse remains a major challenge after transplantation. Most relapses occur in the bone marrow, whereas extramedullary relapse is relatively uncommon, and relapse involving the female reproductive system is extremely rare. Herein, we report a case of ALL with uterine and ovarian relapse after allo-HSCT. Extramedullary relapse was confirmed by pelvic mass biopsy. The patient subsequently received combined treatment with chemotherapy, radiotherapy, and chimeric antigen receptor T‑cell (CAR‑T) immunotherapy, resulting in complete regression of the uterine and ovarian lesions and achieving clinical remission. It should be noted that relapse of acute leukemia in the reproductive system after transplantation can be easily misdiagnosed as a primary malignancy of the reproductive system. Therefore, accurate differentiation between primary and secondary tumors and early initiation of effective treatment are essential. In clinical practice, diagnostic accuracy should be improved by integrating the patient's clinical history with magnetic resonance imaging (MRI) findings, thereby avoiding unnecessary surgical trauma and improving long‑term prognosis.