gms | German Medical Science

Objective: Treatment strategies for cystic craniopharyngiomas are still under debate particularly for the young population. We here present for the first time tumor control and functional outcome data after stereotactic (STX) and conventional surgical treatment.

Methods: From our prospective database, we identified pediatric and adolescent craniopharyngioma patients consecutively treated between 1990 and 2019. Treatment decisions in favor of microsurgery (transcranial/transsphenoidal) or STX treatment were made interdisciplinary. STX included aspiration of the cystic formation and/or implantation of an internal shunt catheter for continuous up- (ventricular system) and downstream (basal cisterns) drainage. Study endpoints were progression free survival (PFS), time to radiation, and functional outcome. The crossover rate from STX to microsurgical treatment was additionally analyzed. Functional outcome included ophthalmological, endocrinological and body-mass index (BMI) data.

Results: 36 patients (median age 9.9 yrs) were analyzed including 33 (3) cystic (solid) tumors. STX was applied in 16, transsphenoidal (transcranial) microsurgery in 7 (13) tumors. Tumor volume reduction was achieved with either method (median 82 to 9cm³; p<0.001). Improvement of visual dysfunction was achieved in all patients independent of the applied treatment modality. Overall, 5-year PFS was 49% (median FU 81 months). 5-year PFS was 33%, 60%, and 67% after STX, transsphenoidal and transcranial resection, respectively (p=0.2). The 5-year crossover rate from STX to transcranial resection was 40% (median 106 months). The 5-year probability for external beam radiation was 5% (median 155 months) after initial treatment and not different among the applied treatment strategies. Endocrinological worsening/BMI increase) was most pronounced in patients undergoing external beam radiation (100%/8kg/m²), in-between after open tumor resection alone (63%/6kg/m²) and best in patients undergoing exclusively stereotactic treatments (22%/3kg/m²) (p=0.001). In multivariate analyses external beam radiation was associated with hypothalamic dysfunction (p=0.005).

Conclusion: STX represents a minimal invasive treatment option for cystic craniopharyngiomas and is associated with a favorable rate of functional deterioration. STX enlarges the therapeutic platform for predominantly cystic tumors. Personalized localized treatment options offer the chance to withhold radiation therapy in the vast majority of patients.