Fluorescein sodium-guided biopsy or resection in primary central nervous system lymphomas with contrast-enhancing lesion in MRI.

Background: Surgical procedures are critical in making a conclusive histopathological diagnosis of primary central nervous system lymphoma (PCNSL), which typically presents contrast-enhancing lesions in magnetic resonance imaging (MRI). The fluorescein sodium-guided technique could enhance tumor visibility. We reported a series of patients with PCNSL underwent fluorescein sodium-guided surgical procedures.
Patients and Methods: 12 patients clinically considered brain tumors underwent fluorescein sodium-guided surgery in Sun Yat-sen University Cancer Center from March 2016 to July 2017. The age of 4 female and 8 male patients ranges from 39 to 62 years. In 4 patients, corticosteroid had been prescribed before surgery due to intracranial hypertension. After injection of low dose of sodium fluorescein (3-5 mg/kg), the lesions with strong fluorescence staining were identified as the target area for biopsy or resection.
Results: Based on the targeted tissues with bright and homogenous fluorescence staining, all 12 patients were conclusively diagnosed as B cell non-Hodgkin's lymphoma (diffuse large cell). The specificity of the specimens sent for frozen section was 86.4% (19/22). No fluorescein sodium associated side effects were observed.
Conclusion: Fluorescein sodium guided surgery is an effective and safe tool in biopsy or tumor resection in patients suspicious for PCNSL with preoperative MRI presented contrast-enhanced homogenous lesions. Such technique might still be considered in those patients who have been pretreated with corticosteroid.