Fourth Ventricular Lesions in Metastatic Gliomas: A Rare Predilection?

Clinical characteristics and prognosis of Glioblastoma patients with infratentorial recurrence

BACKGROUND

Glioblastoma (GBM) infrequently recurs in the infratentorial region. Such Infratentorial recurrence (ITR) has some clinically unique characteristics, such as presenting unspecific symptoms and providing patients a chance to receive additional radiotherapy. However, the clinical significances of ITR are not well studied.

METHODS

We reviewed newly diagnosed isocitrate dehydrogenase (IDH)-wildtype GBM patients treated at our institution between October 2008 and December 2018. ITR was defined as any type of recurrence in GBM, including dissemination or distant recurrence, which primarily developed in the supratentorial region and recurred in the infratentorial region.

RESULTS

Of 134 patients with newly diagnosed IDH-wildtype GBM, six (4.5%) were classified as having ITR. There was no significant difference in median duration from the first surgery to ITR development between patients with and without ITR (12.2 vs. 10.2 months, P = 0.65). The primary symptoms of ITR were gait disturbance (100%, n = 6), dizziness (50.0%, n = 3), nausea (33.3%, n = 2), and cerebellar mutism (16.7%, n = 1). In four cases (66.7%), symptoms were presented before ITR development. All patients received additional treatments for ITR. The median post-recurrence survival (PRS) of ITR patients was significantly shorter than that of general GBM patients (5.5 vs. 9.1 months, P = 0.023). However, chemoradiotherapy contributed to palliating symptoms such as nausea.

CONCLUSIONS

ITR is a severe recurrence type in GBM patients. Its symptoms are neurologically unspecific and can be overlooked or misdiagnosed as side effects of treatments. Carefully checking the infratentorial region, especially around the fourth ventricle, is essential during the GBM patient follow-up.

T2/FLAIR Abnormity Could be the Sign of Glioblastoma Dissemination

Purpose

Newly emerged or constantly enlarged contrast-enhancing (CE) lesions were the necessary signs for the diagnosis of glioblastoma (GBM) progression. This study aimed to investigate whether the T2-weighted-Fluid-Attenuated Inversion Recovery (T2/FLAIR) abnormal transformation could predict and assess progression for GBMs, especially for tumor dissemination.

Methods

A consecutive cohort of 246 GBM patients with regular follow-up and sufficient radiological data was included in this study. The series of T2/FLAIR and T1CE images were retrospectively reviewed. The patients were separated into T2/FLAIR and T1CE discordant and accordant subgroups based on the initial progression images.

Results

A total of 170 qualified patients were finally analyzed. The incidence of discordant T2/FLAIR and T1CE images was 25.9% (44/170). The median time-span of T2/FLAIR indicated tumor progression was 119.5 days (ranging from 57 days-unreached) prior to T1CE. Nearly half of patients (20/44, 45.5%) in the discordant subgroup suffered from tumor dissemination, substantially higher than accordant patients (23/126, 20.6%, p < 0.001). The median time to progression (TTP), post-progression survival (PPS), and overall survival (OS) were not statistically different (all p > 0.05) between discordant and accordant patients.

Conclusions

T2/FLAIR abnormity could be the sign of GBM progression, especially for newly emerged lesions disseminating from the primary cavity. Physicians should cast more attention on the dynamic change of T2/FLAIR images, which might be of great significance for progression assessment and subsequent clinical decision-making.

Supratentorial high-grade astrocytoma with leptomeningeal spread to the fourth ventricle: a lethal dissemination with dismal prognosis

PURPOSE

Leptomeningeal spread to the fourth ventricle (LSFV) from supratentorial high-grade astrocytoma (HGA) is rarely investigated. The incidence and prognostic merit of LSFV were analyzed in this study.

METHODS

A consecutive cohort of 175 patients with pathologically diagnosed HGA according to the 2016 WHO classification of brain tumors was enrolled. LSFV was defined as radiological occupation in the fourth ventricle at the moment of initial progression. Clinical, radiological, and pathological data were analyzed to explore the difference between HGA patients with and without LSFV.

RESULTS

There were 18 of 175 (10.3%) HGAs confirmed with LSFV. The difference of survival rate between patients with LSFV or not was significant in both overall survival (OS) (14.5 vs. 24 months, P =  0.0007) and post progression survival (PPS) (6.0 vs. 11.5 months, P = 0.0004), while no significant difference was observed in time to progression (TTP) (8.5 months vs. 9.5 months P = 0.6795). In the Cox multivariate analysis, LSFV was confirmed as an independent prognostic risk factor for OS (HR 2.06, P = 0.010). LSFV was correlated with younger age (P = 0.044), ventricle infringement of primary tumor (P < 0.001) and higher Ki-67 index (P = 0.013) in further analysis, and the latter two have been validated in the Logistic regression analysis (OR 18.16, P = 0.006; OR 4.04, P = 0.012, respectively).

CONCLUSION

LSFV was indicative of end-stage for supratentorial HGA patients, which shortened patients' PPS and OS instead of TTP. It's never too cautious to alert this lethal event when tumor harbored ventricle infringement and higher Ki-67 index in routine clinical course.