RESUMEN
Background: Children with craniopharyngiomas (CPs) typically suffer from a life-long chronic disease. The younger the child, the more vulnerable the maturing brain is to invasive therapies such as surgery or radiotherapy. Therefore, treatment modalities facilitating avoidance or delay of invasive therapies are beneficial for these patients. In the last decade, intracystic injection of interferon alfa-2a or alfa-2b evolved as a treatment of choice based on efficacy and minor toxicity. However, the drug is no longer available internationally. After an extensive pharmacological review, peginterferon alfa-2a was identified as the agent with closest similarity. Methods: A retrospective case series is described, including five patients treated with intracystic peginterferon alfa-2a for cystic CP according to an innovative care protocol. After initial CP cyst aspiration, peginterferon alfa-2a was injected once per week via an Ommaya reservoir for 6 weeks followed by response assessment with MRI. Results: Patients' age ranged from 4 to 54 years (four patients <12 years, one adult patient). Intracystic therapy with peginterferon alfa-2a was tolerated well by all five individuals without any major toxicities and resulted in cyst shrinkage in all of the five patients. The importance of a permeability study prior to commencing intracystic therapy became apparent in one patient who suffered from cyst leakage. Conclusions: Intracystic treatment with peginterferon alfa-2a was found to be a tolerable and efficacious treatment modality in patients with cystic CP. This experience warrants further research with a larger number of patients with measurement of long-term efficacy and safety outcomes.
RESUMEN
PURPOSE: Various surgical nuances of the telovelar approach have been suggested. The necessity of removing the posterior arch of C1 to accomplish optimal tumor exposure is still debated. Therefore, we report on our experience and technical details of the fourth ventricular tumor resection in a modified prone position without systematic removal of the posterior arch of C1. METHODS: A retrospective analysis of all pediatric patients, who underwent a fourth ventricular tumor resection in the modified prone position between 2012 and 2021, was performed. RESULTS: We identified 40 patients with a median age of 6 years and a M:F ratio of 25:15. A telovelar approach was performed in all cases. In 39/40 patients, the posterior arch of C1 was not removed. In the remaining patient, the reason for removing C1 was tumor extension below the level of C2 with ventral extension. Gross or near total resection could be achieved in 34/39 patients, and subtotal resection in 5/39 patients. In none of the patients, a limited exposure, sight of view, or range of motion caused by the posterior arch of C1 was encountered, necessitating an unplanned removal of the posterior arch of C1. Importantly, in none of the cases, the surgeon had the impression of a limited sight of view to the most rostral parts of the fourth ventricle, which necessitated a vermian incision. CONCLUSION: A telovelar approach without the removal of the posterior arch of C1 allows for an optimal exposure of the fourth ventricle provided that critical nuances in patient positioning are considered.