The impact of COVID-19 on 2020 monthly incidence trends of primary brain and other CNS tumors

BACKGROUND

To mitigate disease spread, restrictions implemented in the United States surrounding the COVID-19 pandemic created an environment that led to delays in cancer diagnosis. The data needed to accurately analyze the impact of the pandemic on brain and CNS tumor incidence has not been available until now. Utilizing incidence data from the Central Brain Tumor Registry of the United States (CBTRUS) we analyzed the impact of the COVID-19 pandemic on primary brain and other CNS tumor incidence for the first year of the pandemic.

METHODS

Monthly age-adjusted incidence rates and incidence trends for 2019 and 2020 were determined for age at diagnosis, sex, race, ethnicity, diagnostic confirmation, behavior, tumor histopathology, and county-level urbanization. Monthly incidence rate ratios comparing 2020 and 2019 were evaluated for the same factors.

RESULTS

Overall, there was a notable decrease in incidence rates in March-May 2020 when compared to 2019. These decreases were driven by nonmalignant tumors, with a 50% incidence decrease between March 2020 and 2019. Individuals who were Black had a larger incidence decrease in early 2020 than individuals who were White. Radiographically confirmed tumors saw larger incidence decreases than histologically confirmed tumors. There were no changes in monthly incidence of glioblastoma in 2020 compared to 2019.

CONCLUSIONS

These data provide evidence that disruptions in medical care, such as governmental and health care mandates, in response to the COVID-19 pandemic resulted in an overall decreased incidence of primary brain tumors in early 2020.

Targeting Ion Channels: Blockers Suppress Calcium Signals and Induce Cytotoxicity Across Medulloblastoma Cell Models

Medulloblastoma (MB) groups 3 and 4 lack targeted therapies despite their dismal prognoses. Ion channels and pumps have been implicated in promoting MB metastasis and growth; however, their roles remain poorly understood. In this study, we repurposed FDA-approved channel blockers and modulators to investigate their potential anti-tumor effects in MB cell lines (DAOY and D283) and primary cell cultures derived from a patient with MB. For the first time, we report spontaneous calcium signaling in MB cells. Spontaneous calcium signals were significantly reduced by mibefradil (calcium channel blocker), paxilline (calcium-activated potassium channel blocker), and thioridazine (potassium channel blocker). These drugs induced dose-dependent cytotoxicity in both the DAOY and D283 cell lines, as well as in primary cell cultures of a patient with group 3 or 4 MB. In contrast, digoxin and ouabain, inhibitors of the Na/K pump, reduced the calcium signaling by over 90% in DAOY cells and induced approximately 90% cell death in DAOY cells and 80% cell death in D283 cells. However, these effects were significantly diminished in the cells derived from a patient with MB, highlighting the variability in drug sensitivity among MB models. These findings demonstrate that calcium signaling is critical for MB cell survival and that the targeted inhibition of calcium pathways suppresses tumor cell growth across multiple MB models.