Kyoji Tsuda

Decrease in the Apparent Diffusion Coefficient in Peritumoral Edema for the Assessment of Recurrent Glioblastoma Treated by Bevacizumab

PURPOSES Anti-edema effect of bevacizumab was evaluated using the apparent diffusion coefficient (ADC) of peritumoral edema associated with regional cerebral blood flow (rCBV) of the tumor. MATERIALS AND METHODS Nine patients with recurrent glioblastoma were treated using bevacizumab for 4 ∼ 36 months (average 12 months). MRI was performed every 2 months. For each MRI, ADC value, Gd-enhanced area on T1 imaging, area of peritumoral edema on T2 imaging, and rCBV on perfusion imaging were measured. ADC and rCBV values were determined by the use of regions of interest positioned in areas of high signal intensity, as seen on T2-weighted images and ADC maps. RESULTS After 2 months of bevacizumab treatment, ADC values and rCBV decreased 49 and 32 % respectively, associated with marked diminishment of the Gd-enhanced area compared with pretreatment. After 6 months, in 5 of the 9 cases, the Gd-enhanced area appeared again with no change in the ADC value and rCBV. In the other four cases, the Gd-enhanced area as well as the ADC value and rCBV returned to the initial status. CONCLUSION The anti-edema effect of bevacizumab for treatment of recurrent glioblastoma that was demonstrated by decreased ADC values and rCBV was dramatic and -prolonged at 6 months even with tumor progression.

Is Simpson Grade I Removal Necessary in All Cases of Spinal Meningioma? Assessment of Postoperative Recurrence during Long-Term Follow-up

It is generally accepted that the first choice of treatment for spinal meningiomas is “radical” surgical removal. However, Simpson grade I removal is sometimes difficult, especially in cases with ventral dural attachment, because of the risk of spinal cord damage or the difficulty of dural repair after radical resection. In addition, there is no consensus on a surgical strategy for radicality, whether or not Simpson grade I resection should be performed in all cases of spinal meningioma. In this study, we retrospectively analyzed clinical and radiological data of surgically treated 14 patients with spinal meningioma, to assess the influence of the Simpson grade to tumor recurrences during long-term follow-up (median 8.2 years, 1.3–27.9). The number of patients in Simpson grades I, II, III, and IV were 2, 8, 0, and 3, respectively; Simpson grading was not applicable to one patient with non-dura-based meningioma. No postoperative permanent neurological worsening was encountered. The recurrence rate was 21.4% (3 out of 14 cases). Of these 3 recurrent cases, 1 was a case of non-dura-based meningioma and another was a case of neurofibromatosis type 2 (NF2); both of them are known as risk factors for recurrence after surgical removal of spinal meningiomas. Considering this background of these two recurrences, the clinical results of the present study are consistent with previous results. Therefore, we propose that surgeons do not always have to achieve Simpson grade I removal if dural repair is complicated and postoperative cerebrospinal fluid (CSF) leakage or neurological worsening are estimated after resection of dural attachment and repair of dural defect.

Brain metastasis from papillary thyroid carcinomas

Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma and has a relatively favorable prognosis. PTC brain metastases are rare, occurring in 0.1–5% of cases in previous studies. In the present study, we treated 5 cases of PTC brain metastasis in our institute and retrospectively evaluated these patients. A retrospective database was generated from the patient medical records of our institution for the years between 1976 and 2011. The mean patient age at diagnosis was 64.6 years and the average duration from PTC resection to the detection of a brain metastasis using magnetic resonance imaging (MRI) or computed tomography (CT) was 91.7 months. The patients were treated with various combinations of surgery and radiation therapy. All 5 patients died and the mean overall survival following the diagnosis of a brain metastasis was 9.0 months. One patient succumbed to an intratumoral hemorrhage of the metastatic brain tumor. The remaining patients died following metastasis to other organs. Our findings suggest that PTC brain metastases may occur at the end-stage of patient treatment and result in an unfavorable prognosis. Patients with brain metastases also succumbed to the development of metastases to the fetal organs rather than brain.