Circumscribed low-grade astrocytoma with a synchronous occipital lesion of uncertain pathology in an adolescent with T-cell lymphoblastic lymphoma.

Circumscribed astrocytic glioma, defined by the 2021 WHO Central Nervous System tumour classification, exhibits expansive growth patterns. Despite increasing molecular and histological data, their applicability to adolescents and young adults remains uncertain. Also, the coexistence of T-cell lymphoblastic lymphoma (T-LBL) and circumscribed astrocytic glioma is rare, and no established treatment protocols currently exist.A male in his late teens presented with T-LBL and concurrent intracranial masses in the left paracentral lobule and occipital lobe. Despite achieving a complete response for T-LBL with standard chemotherapy and transplantation, the intracranial lesion (paracentral lobule) progressed. Resection of the paracentral lesion revealed a circumscribed low-grade astrocytoma, not otherwise specified. At 1-year follow-up, without adjuvant therapy, no recurrence was observed and the residual occipital lesion decreased in size.Through interdepartmental collaboration, we achieved a favourable outcome, though the impact of T-LBL treatment on glioma remains unclear. Further studies are needed to establish optimal management for complex cases.