To evaluate the feasibility of retroperitoneoscopic heminephroureterectomy for children with duplex anomaly.Retroperitoneoscopic heminephroureterectomy was performed in five children (four girls and one boy) with complete duplication of the ureter, of whom four (age range 1-5 years; mean age 3.3 years) had upper pole ectopic megaureters and one (3 years old) had an upper pole megaureter with ureterocele. In the patient with ureterocele, distal ureterectomy and ureterocelectomy were performed by Pfannenstiel incision.The mean operation time was 346 min (range 270-450 min) in the four patients with ectopic megaureter and 420 min (330 min for heminephroureterectomy) in the patient with ureterocele. The mean estimated blood loss was 43 mL (range 5-100 mL) in the four patients with ectopic megaureter and 40 mL in the patient with ureterocele. No postoperative complications were observed. Postoperative intravenous pyelography showed normal pyelogram and renal function of the preserved lower pole in all cases.Retroperitoneoscopic heminephroureterectomy for children is feasible, safe and has good postoperative results, including cosmetic results. However, the operation time needs to be reduced.
The development of high-throughput anticancer drug screening methods using patient-derived cancer cell (PDC) lines that maintain their original characteristics in an in vitro three-dimensional (3D) culture system poses a significant challenge to achieving personalized cancer medicine. Because stromal tissue plays a critical role in the composition and maintenance of the cancer microenvironment, in vitro 3D-culture using reconstructed stromal tissues has attracted considerable attention. Here, a simple and unique in vitro 3D-culture method using heparin and collagen together with fibroblasts and endothelial cells to fabricate vascularized 3D-stromal tissues for in vitro culture of PDCs is reported. Whereas co-treatment with bevacizumab, a monoclonal antibody against vascular endothelial growth factor, and 5-fluorouracil significantly reduced the survival rate of 3D-cultured PDCs to 30%, separate addition of each drug did not induce comparable strong cytotoxicity, suggesting the possibility of evaluating the combined effect of anticancer drugs and angiogenesis inhibitors. Surprisingly, drug evaluation using eight PDC lines with the 3D-culture method resulted in a drug efficacy concordance rate of 75% with clinical outcomes. The model is expected to be applicable to in vitro throughput drug screening for the development of personalized cancer medicine. To replicate the tumor microenvironment in vitro, we constructed a cancer-stromal tissue model in which cancer cells are placed above and inside stromal tissue with vascular network structures derived from vascular endothelial cells in fibroblast tissue using CAViTs method. Using this method, we were able to reproduce the invasion and metastasis processes of cancer cells observed in vivo. Using patient-derived cancer cells, we assessed the possibility of evaluating the combined effect with an angiogenesis inhibitor. Further, primary culture was possible, suggesting that the model may be useful for new in vitro drug screening and personalized cancer medicine.
e15090 Background: We developed a new shape memory alloy (SMA) probe for percutaneous treatment of renal cell carcinoma (RCC) by electro-vaporization, and investigated its efficacy and safety in experimental models. Methods:The SMA electrode can be manipulated to any shape at room temperature and regains its original shape at ≥ 65 °C. By adding a high-frequency electric current to the probe, the electrodes quickly regain their original shape and vaporize tissues into a spherical defect. The performance of this probe was tested using agar, dog kidney and rat RCC models. The treatment effect was evaluated by magnetic resonance imaging (MRI) and histological examination. Results: The vaporizing electrode produces heat due to its own resistance to the high frequency electric current, and vaporizes surrounding agar. In the agar model, the electro-vaporization inside the spherical electrode was successfully achieved in several seconds. The area of ≥ 60 °C extended about 5 mm beyond the periphery of the vaporized part, and corresponded with the histological findings on the dog kidney that an irreversible heat denaturation occurred to the same extent. A tumor model made by transplanting RCC cell line in the subcutaneous tissue of nude rats. After applying the electorical current, the electrode part completely recovered to a full sphere shape. The study on the RCC model also confirmed that about 5 mm extent of heat denaturation was seen in the muscular tissue adjacent to the tumor. In the study using the RCC model, some remaining tissues close to the tumor were observed after vaporization. However, dynamic MRI demonstrated no enhancement in this area and no viable tumor cells were documented by histological examination. Conclusions: This novel tissue ablation system has potential as a viable option for percutaneous treatment of renal tumors.
