Usefulness and pitfalls of neuroendoscopic tumor biopsy for intracranial malignant lymphoma

Neuroendoscopic biopsy has various advantages, such as being able to collect larger tissue samples and achieving more efficient hemostasis compared to needle biopsy. The purpose of this study is to review the surgical techniques, accuracy of pathological diagnosis, and perioperative complications of patients with intracerebral malignant lymphoma who were diagnosed mainly by neuroendoscopic biopsy.

A total of 65 patients diagnosed as having malignant lymphoma, via mainly neuroendoscopic biopsy, were analyzed retrospectively. A flexible neuroendoscope was used for ventricular and paraventricular lesions, which was inserted via the lateral ventricle. For intraparenchymal lesions, rigid scopes with navigation systems were used.

The main location of the tumors was in the intraventricular/paraventricular regions in 22 patients, in the deep white matter in 22 patients, in the basal ganglia in 14 patients, and in the cerebellum in 5 patients. Two patients had a lymphomatosis cerebri-like lesion. Lymphoma was diagnosed in 58 of the 65 patients, with most patients diagnosed as having diffuse large B-cell lymphoma. Incorrect diagnoses were owing to inappropriate samples, sentinel lesions, or preoperative treatments, such as with steroids. Complications included small cerebral hematoma in 5 patients, severe cerebral edema in 3 patients (2 fatal), and brain abscess and arterial bleeding leading to infarction in 1 case each.

Neuroendoscopic biopsy is a reliable diagnostic approach for intracranial malignant lymphomas, particularly those in deep or intraventricular/paraventricular locations. However, caution is particularly required for patients with severe cerebral swelling, which may cause death, and those with prior sentinel lesions.