Distant recurrence in the cerebellar dentate nucleus through the dentato-rubro-thalamo-cortical pathway in supratentorial glioma cases

BACKGROUND

Distant recurrence can occur by infiltration along white matter tracts or dissemination through the cerebrospinal fluid (CSF). This study aimed to clarify the clinical features and mechanisms of recurrence in the dentate nucleus (DN) in patients with supratentorial gliomas. Based on the review of our patients, we verified the hypothesis that distant DN recurrence from a supratentorial lesion occurs through the dentato-rubro-thalamo-cortical (DRTC) pathway.

METHODS

A total of 380 patients with supratentorial astrocytoma, isocitrate dehydrogenase (IDH)-mutant (astrocytoma), oligodendroglioma, IDH mutant and 1p/19q-codeleted (oligodendroglioma), glioblastoma, IDH-wild type (GB), and thalamic diffuse midline glioma, H3 K27-altered (DMG), who underwent tumor resection at our department from 2009 to 2022 were included in this study. Recurrence patterns were reviewed. Additionally, clinical features and magnetic resonance imaging findings before treatment, at the appearance of an abnormal signal, and at further progression due to delayed diagnosis or after salvage treatment of cases with recurrence in the DN were reviewed.

RESULTS

Of the 380 patients, 8 (2.1%) had first recurrence in the DN, 3 were asymptomatic when abnormal signals appeared, and 5 were diagnosed within one month after the onset of symptoms. Recurrence in the DN developed in 8 (7.4%) of 108 cases of astrocytoma, GB, or DMG at the frontal lobe or thalamus, whereas no other histological types or sites showed recurrence in the DN. At the time of the appearance of abnormal signals, a diffuse lesion developed at the hilus of the DN. The patterns of further progression showed that the lesions extended to the superior cerebellar peduncle, tectum, tegmentum, red nucleus, thalamus, and internal capsule along the DRTC pathway.

CONCLUSION

Distant recurrence along the DRTC pathway is not rare in astrocytomas, GB, or DMG at the frontal lobe or thalamus. Recurrence in the DN developed as a result of the infiltration of tumor cells through the DRTC pathway, not dissemination through the CSF.

Posterior fossa recurrence of WHO grade II and III supratentorial gliomas

OBJECTIVE/BACKGROUND

Posterior fossa (PF) recurrences of supratentorial (ST) World Health Organization (WHO) grade II and III gliomas are thought to be rare and to have grim prognoses.

METHODS

This study entailed searching through our database and reviewing the records of patients with grade II and III ST gliomas who developed PF recurrence with no overt secondary gliomatosis or leptomeningeal spread.

RESULTS

Of 2266 grade II and III gliomas, 14 fulfilled the inclusion criteria: 5 oligodendrogliomas (O; 1 OII, 4 OIII); 7 astrocytomas (A; 4 AII, 3 AIII); and 2 oligoastrocytomas (OA; both OAIII). The male/female gender ratio was 10/4, and median age at recurrence was 43 years. Two groups were identified. In one group (n=8; 1 AII, 3 AIII, 2 OAIII, 2 OIII), a rapidly growing contrast-enhancing PF mass (6/8) was associated with ST progression, and median survival time after detection was only 6.5 months despite radiotherapy and/or chemotherapy. In the second group (n=6; 3 AII, 1 OII, and 2 OIII), a non-contrast-enhancing (5/6), asymptomatic (5/6), slow-growing PF mass remained isolated, and treatment with radio- or chemotherapy produced objective responses in three patients and durable stabilization in the remaining three. After a median follow-up of 63months, only one patient died due to delayed recurrence of the ST lesion, while the remaining five patients are still alive.

CONCLUSION

Non-contiguous PF relapses of ST grade II and III gliomas are rare. A high-grade ST tumor that is concomitantly progressing appears to be a predictor of poor survival. Conversely, the tumor course may be indolent if the ST lesion is low-grade and non-progressive at the time of PF involvement. The possible mechanism(s) behind this tropism are also discussed.