Harvey Cushing's craniopharyngioma treatment: Part 2. Surgical strategies and results of his pioneering series

OBJECTIVE Harvey Cushing (1869-1939) developed pioneering surgical techniques for craniopharyngioma (CP) removal. This study exhaustively analyzes the pathological variables and surgical strategies that influenced Cushing's results in his entire series of CP patients. METHODS The CP records from Cushing's Brain Tumor Registry were carefully reviewed, as were his CP cases published in medical monographs and scientific reports. RESULTS One hundred twenty-four tumors with characteristics typical of CP comprise Cushing's entire series (CP124). Cushing performed 198 surgical procedures in the patients in whom these tumors were treated, with a 23% mortality rate within the first 2 months after surgery. Three periods in Cushing's CP surgical career can be differentiated: an early period (1901-1917, 39 patients) characterized by his use of the transsphenoidal approach and limited cyst drainage procedures, an intermediate period (1919-1925, 42 patients) in which the subfrontal approach was the standard procedure and maximal removal was attempted, and a late period (1926-1932, 43 patients) characterized by the use of air ventriculography for topographical diagnosis and limited resections via a transventricular approach. Among Cushing's CP series were 92 cases that were pathologically verified (CP92). In this subcohort, the unilateral subfrontal approach was predominantly used (72% of cases), followed by the transsphenoidal (15%) and frontal transcortical-transventricular (8%) approaches. Drainage of the CP cystic component or partial excision of the solid component was achieved in 61% of the cases, subtotal removal in 23%, and macroscopic total removal in 10%. Satisfactory outcomes were obtained in 55% of the patients in CP 92 , whereas poor outcomes and/or death related to hypothalamic injury was observed in 28%. Postoperative symptoms related to hypothalamic dysfunction occurred 53% of the time. The subfrontal approach yielded the highest rates of radical removal (p < 0.001) and good outcomes (p = 0.01). Partial removals were associated with the highest rates of poor outcomes, including death (p = 0.009). Cushing's removal of CPs with a primary infundibulo-tuberal topography or showing third ventricle invasion was associated with the highest rates of hypothalamic injury (p < 0.001) and the worst outcomes (p = 0.009). CONCLUSIONS Harvey Cushing's techniques and surgical philosophy varied substantially throughout his career. The experience he gained with this large CP series made him aware of the importance of limiting the extent of tumor removal and leaving untouched the tumor portion strongly adhered to the hypothalamus.