Efficacy of simultaneous single-trajectory endoscopic tumor biopsy and endoscopic cerebrospinal fluid diversion procedures in intra- and paraventricular tumors.

OBJECT: Intraventricular and paraventricular tumors resulting in hydrocephalus commonly require a CSF diversion procedure. A tumor biopsy can often be performed concurrently. Although the tissue samples obtained during endoscopic biopsy procedures are small, a diagnosis can be made in most cases. In the present study the authors analyzed the efficacy of concurrent endoscopic biopsy and CSF diversion procedures using a single bur hole and trajectory.

METHODS: Eighty-seven patients with intraventricular and paraventricular tumors were treated with endoscopic biopsy and CSF diversion procedures using a rigid rod-lens endoscope or a rigid fiberscope during a 10-year period. All patients underwent a tumor biopsy and an endoscopic third ventriculostomy (ETV), aqueductal stenting (AS), or ventriculoperitoneal (VP) shunting, depending on the tumor location and site of obstruction. A single bur hole for both procedures was used in all patients.

RESULTS: Among the 87 patients, the biopsy was diagnostic in 72 (83%) and merely suggestive in 7 (8%); in 8 patients (9%) the sample was nondiagnostic. Among the 22 patients who underwent an initial endoscopic biopsy and subsequent procedures, the specimen obtained at the second surgery was concordant with the initial endoscopic biopsy sample in 13 patients; it was somewhat similar in 4 patients. In the other 5 patients, either a microsurgical or stereotactic approach was used to correctly diagnose the pathology. Fifty-five patients were considered for endoscopic CSF diversion procedures; an ETV was performed in 52 patients and AS in 2. An ETV could not be performed in 3 patients for technical reasons. A VP shunt was inserted in 32 patients, with 25 undergoing shunt placement at the same time as the ETV and 7 at a later date. Significant bleeding was encountered in 3 patients during the tumor biopsy and in 1 patient during the ETV. The ETV failed in 1 patient during the follow-up, and a repeat ETV was required.

CONCLUSIONS: Endoscopic biopsy sampling and a concurrent CSF diversion procedure through a single bur hole and trajectory can be considered for intraventricular tumors. The overall success rates of 83% for the biopsy procedure and 86% for the ETV indicate that the procedures are beneficial in the majority of cases. A concordance rate of 75% was found in patients who underwent an initial biopsy procedure and a subsequent microsurgical approach for tumor excision.