Association of Surgical Resection, Disability, and Survival in Patients with Glioblastoma.

OBJECTIVE: Extent of resection (EOR) and Karnofsky Performance Status (KPS) are at odds in glioblastoma (GBM) surgery, that is, the anticipated postoperative disability limits the EOR. This study analyzes the correlation of different surgical modalities with the resulting physical status and survival of patients with GBM. METHODS: A total of 565 patients with primary GBM were operated on in a single institution between 2006 and 2014. Possible surgical modalities comprised supratotal resection (SLR), gross total resection (GTR; ≥ 95% by volume), tumor debulking (TDB; ≤ 95% by volume), and stereotactic biopsy (SB). Pre- and postoperative KPS before and up to 4 weeks after surgery as well as overall survival (OS) rate were determined retrospectively. Hazard ratio (HR) and 95% confidence intervals were calculated using a Cox proportional hazards model. RESULTS: Median postoperative KPS was ≥ 70, irrespective of surgical modality. Mean OS was 12.5 months. Multivariate analysis revealed age ≥ 70 years (HR: 1.93), preoperative KPS < 70 (HR: 2.15), and unmethylation in MGMT promoter (HR: 1.27) as independent factors for worse OS. Regarding surgical modality, SB was associated with the worst survival (HR: 2.3) followed by TDB (HR: 1.36). SLR was inferior to GTR (HR: 1.27). CONCLUSION: Higher EOR in patients with GBM does not seem inevitably correlated with increasing functional impairment, but better survival, provided there is a balanced preoperative indication. Nevertheless, SLR does not seem to be superior to GTR. Whenever possible, maximal safe resection should be considered in patients with GBM, even if an EOR ≥ 95% is not possible.

Microneedle-assisted delivery of verapamil hydrochloride and amlodipine besylate.

The aim of this project was to study the effect of stainless steel solid microneedles and microneedle rollers on percutaneous penetration of verapamil hydrochloride and amlodipine besylate. Verapamil, 2-(3,4-dimethooxyphenyl)-5-[2-(3,4 dimethoxyphenyl)ethyl-methyl-amino]-2-propan-2-yl-pentanenitrile is a calcium channel blocker agent that regulates high blood pressure by decreasing myocardial contractilty, heart rate and impulse conduction. Amlodipine, (R, S)-2-[(2-aminoethoxy) methyl]-4-(2-chlorophenyl)-3-ethoxycarbonyl-5-methoxycarbonyl-6-methyl-1, 4-dihydropyridine, is a calcium channel blocker that is used for the management of hypertension and ischemic heart disease. Passive penetration of verapamil and amlodipine across the skin is low. In vitro studies were performed with microneedle-treated porcine ear skin using vertical static Franz diffusion cells (PermeGear, Hellertown, PA, USA). The receiver chamber contained 5ml of PBS (pH7.4) and was constantly maintained at 37°C temperature with a water circulation jacket. The diffusion area of the skin was 1.77cm(2). The donor compartment was loaded with 1ml of the solution containing 2.5mg/ml of amlodipine besylate. The donor chamber was covered with parafilm to avoid evaporation. Passive diffusion across untreated porcine skin served as control. Aliquots were taken every 2h for 12h and analyzed by liquid chromatography-mass spectrometry. Transcutaneous flux of verapamil increased significantly from 8.75µg/cm(2)/h to 49.96µg/cm(2)/h across microneedle-roller treated porcine skin. Percutaneous flux of amlodipine besylate following the use of stainless steel microneedles was 22.39µg/cm(2)/h. Passive flux for the drug was 1.57µg/cm(2)/h. This enhancement of amlodipine flux was statistically significant. Transdermal flux of amlodipine with microneedle roller was 1.05µg/cm(2)/h in comparison with passive diffusion flux of 0.19µg/cm(2)/h. The difference in flux values was also statistically significant. Stainless steel solid microneedles and microneedle rollers increased percutaneous penetration of verapamil hydrochloride and amlodipine besylate. It may be feasible to develop transdermal microneedle patches for these drugs.