Autologous stem cell transplantation experience in an adult recurrent medulloblastoma patient: Case report

Abstract

Case report: Introduction: Medulloblastoma is the most common malignant primary embryonal brain tumor in children and occurs in the cerebellum. Approximately 70% of patients are diagnosed before the age of 20. The disease is rare after the 4th decade of life. It originates from the brainstem and metastasizes to other brain tissue, ventricles and medulla spinalis via CSF. Metastasis to bone, bone marrow, lung or lymph nodes outside the CNS is a very rare condition.Surgery, chemotherapy and radiotherapy are used in the treatment of medulloblastoma. In some patients (patients in the high-risk group, relapsed/refractory patients), autologous stem cell transplantation(ASCT) is performed following high-dose chemotherapy to increase survival rates.Here, we will present a case of medulloblastoma in which we performed autologous stem cell transplantation in our center.Key words: Medulloblastoma, autologous stem cell transplantation Case report: A 30-year-old male patient applied to the neurology clinic in May 2020 with complaints of headache, dizziness, nausea, vomiting and fainting. In the brain imaging, a 6 × 4 cm mass lesion was observed in the posterior fossa, located in the ventricle and causing compression symptoms (Cystic Astrocytoma? Medulloblastoma?). The patient underwent ventriculoperitoneal shunt and subtotal mass excision at the neurosurgery clinic. The biopsy pathology result was reported as medulloblastoma (classical type, p53 mutation positive). Chemotherapy was recommended by the oncology clinic, but the patient did not accept the treatment. In August 2020, the patient was given cranial RT and was subsequently followed without medication.in June 2023 due to complaints of pain and weakness in both lower extremities, there was an intradural mass lesion (25 × 19 mm) obliterating the spinal cord at the T11-T12 level and extending to the extraspinal area, and a diffuse mass lesion within the spinal cord at the T10 level with a craniocaudal length of 17 mm. Mass excision as a result of pathology; It was reported as classical medulloblastoma (non-WNT/non-SHH group (grade 4)).After the patient was given 2 courses of mini-ICE chemotherapy, a nearly complete response in the imaging. The patient was mobilized with G-CSF. In our center, the patient was performed autologous stem cell transplantation (6.55 × 106 /kg cells) with temozolamide (2 × 200mg/m2 on days -6,-5,-4), etoposide (100 mg/m2 on days -7,-6,-5,-4,-3,-2), thiotepa (300 mg/m2, on days -4,-3,-2) protocol in November 2023.The patient, who had neutrophil and platelet engraftment on the 10th day after transplantation, was discharged with outpatient clinic control. Discussion and conclusion: Although the prognosis has improved in children with medulloblastoma, an estimated 20-30% will relapse following initial treatment (1). Recurrences may be local or widespread (brain and vertebra) (2,3,4). In case of recurrent disease after initial treatment, the likelihood of long-term survival is significantly reduced. Autologous hematopoietic cell transplantation after high-dose chemotherapy has been evaluated in small series and resulted in prolonged disease-free survival in approximately 20-25% of patients (7,8). In the study conducted by Eduvian et al., they showed that autologous stem cell transplantation after chemotherapy has a definite, albeit limited, role for selected pediatric brain tumors with poor prognosis and complete/partial remission before transplantation(9).