Vinblastine monotherapy induction prior to radiotherapy for patients with intracranial germinoma during the COVID-19 pandemic

Abstract

Background: Patients with localized intracranial germinoma have excellent survival. Reducing treatment burden and long-term sequelae is a priority. Intensive inpatient chemotherapy (e.g., carboPEI = carboplatin/etoposide/ifosfamide) has been effectively employed to reduce radiotherapy treatment volume/dose. Outpatient-based carboplatin monotherapy is associated with excellent outcomes in metastatic testicular seminoma (an identical pathology), and successful vinblastine monotherapy induction (with 77% tumor volume reduction after just two weekly vinblastine doses) has recently been reported in an intracranial germinoma patient.

Methods: Adapted UK guidelines for germ cell tumor management were distributed during the COVID-19 pandemic, including nonstandard treatment options to reduce hospital visits and/or admissions. This included vinblastine monotherapy for intracranial germinoma (6 mg/m² intravenously, or 4 mg/m² for moderate count suppression, delivered weekly). We describe two such patients treated using this approach.

Results: A 30-year-old male with a localized pineal tumor received 12-week vinblastine induction, with >60% volume reduction, prior to definitive radiotherapy. A 12-year-old female with a metastatic suprasellar tumor and progression at all sites of disease whilst awaiting proton radiotherapy received two vinblastine doses with good early response, including 36% primary tumor volume reduction. The patients tolerated vinblastine well.

Conclusion: Patients with intracranial germinoma have excellent outcomes, and reduction of late effects remains a priority. The description of vinblastine monotherapy in these intracranial germinoma patients warrants further exploration.

Keywords: carboPEI; carboplatin; germinoma; intracranial; monotherapy; vinblastine.

FIGURE 1

Representative sagittal T1‐weighted MRI head images with contrast for Case 1 (localized pineal germinoma) showing response to treatment. (A) At diagnosis, revealing a large, predominantly solid pineal lesion (arrow). (B) After 6 weeks of induction vinblastine monotherapy showing reduction in size of the pineal lesion (arrow). (C) After 12 weeks of vinblastine revealing further modest response to treatment (arrow). (D) Six months after the end of treatment with definitive radiotherapy, showing a small ill‐defined focus of minimally enhancing T1 hyperintensity centered on the site of previous resection (arrow), consistent with further subtle regression of presumed postsurgical changes

FIGURE 2

Representative sagittal T1‐weighted MRI head images with contrast for Case 2 (metastatic suprasellar germinoma) showing response to treatment. (A) At initial progression following diagnosis, whilst awaiting proton craniospinal irradiation. Top arrow highlights representative disease of the cavum septum pellucidum and the lower arrow the primary suprasellar lesion. (B) After two doses of vinblastine, revealing a response at both the primary and metastatic sites (arrows). (C) After completion of proton radiotherapy, showing continued response (arrows). (D) Five months after the end of treatment showing stable residual (arrows)