廣瀬 雄一

Karnofsky Performance Status (KPS) is a widely used scale to assess performance status. KPS ≥ 50% implies that patients can live at home. Therefore, maintaining KPS ≥ 50% is important to improve the quality of life of patients with glioblastoma, whose median survival is less than 2 years. This study aimed to identify the factors associated with survival time with maintenance of KPS ≥ 50% (survival with KPS ≥ 50%) in patients with glioblastoma, IDH-wildtype. Ninety-eight patients with glioblastomas, IDH-wildtype, who were treated with concomitant radiotherapy (RT) and temozolomide (TMZ) followed by maintenance TMZ therapy, and whose KPS at the start of RT was ≥ 50%, were included. The median survival with KPS ≥ 50% was 13.3 months. In univariate analysis, preoperative KPS (≥ 80%), KPS at the start of RT (≥ 80%), residual tumor size (< 2 cm3), methylated MGMT promotor, and implantation of BCNU wafer were associated with survival with KPS ≥ 50%. In multivariate analysis, KPS at the start of RT (≥ 80%), methylated MGMT promotor, and residual tumor size (< 2 cm3) were significantly associated with increased survival with KPS ≥ 50%. A strategy of maximum possible tumor resection without compromising KPS is desirable to prolong the survival time with KPS ≥ 50%.

BACKGROUND AND IMPORTANCE: The usefulness of intraoperative real-time fluorescence navigation using indocyanine green (ICG) for metastatic brain tumors, schwannomas, and meningiomas is well established. However, its application in cases of radiation-induced brain necrosis remains unexplored. Surgical intervention is performed in symptomatic and medically refractory cases; however, radiation-necrotic lesions often exhibit a diffuse pattern with unclear surgical boundaries, making it challenging for surgeons to identify the lesion during the surgery. METHODS: Four patients with intracranial necrotic tissues received 1.5 mg/kg ICG 1 hour before observation during the surgery. We used near-infrared fluorescence to identify the necrotic location. CLINICAL PRESENTATION: Case 1: A 61-year-old man with lung cancer and metastatic brain tumor history exhibited left-sided weakness a year after craniotomy and radiotherapy. A new lesion required surgery, where ICG fluorescence imaging highlighted a significant contrast in the resection cavity, aiding in successful lesion removal without complications. Case 2: A 51-year-old man with resected glioblastoma developed paralysis. ICG fluorescence during surgery confirmed necrosis and enabled the lesion's removal despite potential inaccuracies due to brain shift, without ICG-related complications. Near-infrared fluorescence could visualize necrotic tissues in all 4 cases. The mean signal-to-background ratio of the necrotic tissues in delayed window ICG was 3.5 ± 0.7. The ratio of the gadolinium-enhanced T1 tumor signal to the brain (T1-weighted background ratio) was 2.3 ± 0.4. CONCLUSION: This report is the first to demonstrate the efficacy of ICG intraoperative fluorescence imaging in identifying radiation-induced necrotic brain tissues.

BACKGROUND: To improve the outcome in newly diagnosed glioblastoma patients with maximal resection, we aimed to evaluate the efficacy and safety of implantation of carmustine wafers (CWs), radiation concomitant with temozolomide and bevacizumab, and maintenance chemotherapy with six cycles of temozolomide and bevacizumab. METHOD: This prospective phase II study enrolled glioblastoma patients considered candidates for complete resection (> 90%) of a contrast-enhanced lesion. The CWs were intraoperatively implanted into the resection cavity after achieving maximal resection. Patients without a measurable contrast-enhanced lesion on magnetic resonance imaging within 48 h after resection received concomitant radiotherapy and chemotherapy with temozolomide and bevacizumab, followed by maintenance treatment with up to six cycles of temozolomide and bevacizumab. The primary endpoint was the 2-year overall survival rate in glioblastoma patients with protocol treatment. RESULTS: From October 2015 to April 2018, we obtained consent for the first registration from 70 patients across 17 institutions in Japan, and 49 patients were treated according to the protocol. We evaluated the safety in 49 patients who were part of the second registration and the efficacy in 45 glioblastoma patients treated according to the protocol. The profile of hematological and most of the non-hematological adverse effects was similar to that in previous studies, but stroke occurred in 12% of cases (6/49 patients). The estimated 2-year overall survival rate was 51.3%. CONCLUSION: Implantation of CWs, followed by concomitant radiation, temozolomide, and bevacizumab, and six cycles of temozolomide and bevacizumab may offer some benefit to survival in Japanese glioblastoma patients with maximal resection. TRIAL ID: jRCTs021180007.

BACKGROUND AND OBJECTIVES: To the best of our knowledge, this is the first reported cadaveric feasibility study of leader-follower type robotic-assisted middle cerebral artery (MCA)-radial artery-internal carotid artery anastomosis in the neurovascular surgery field using the da Vinci Xi system (da Vinci Surgical System; Intuitive Surgical, Inc.). Vascular suturing is a necessary skill in neurosurgery; however, the learning curve for deep and high-flow bypasses is severely low. Thus, robot-assisted surgery has been introduced. Here, we describe the surgical workflow adaptations of vascular anastomosis using the da Vinci system to assess the feasibility of robot-assisted anastomoses of the radial and middle cerebral arteries. METHODS: Two fresh cadaver heads were studied using the da Vinci Xi Surgical System with 0° and 30° stereoscopic endoscopes to visualize the neuroanatomy. RESULTS: The da Vinci Xi Surgical System was used throughout the anastomosis of the MCA and intracarotid artery. The optic nerve, optic chiasm, carotid artery, and oculomotor nerve were visualized using standard microdissection techniques. The Sylvian fissure was exposed from the proximal Sylvian membrane to the distal MCA. Using black diamond microforceps and Potts scissors, suturing was achieved on the radial artery-middle cerebral artery using 8-0 Prolene and on the radial artery-internal carotid artery using 7-0 Prolene. CONCLUSION: A bypass of the MCA-radial artery-internal carotid artery can be achieved using the da Vinci Xi Surgical System in cadaver models. This system provides experts and less experienced neurosurgeons with stable bypass techniques for both superficial and deep-seated arteries. However, further studies are needed to evaluate the safety and benefits of the da Vinci Xi Surgical System for bypass procedures.