Our 10-year experience with embolized Wilms' tumor

Successful transcatheter arterial embolization to control intratumoral hemorrhage in clear cell sarcoma of the kidney

Clear cell sarcoma of the kidney (CCSK) is a rare aggressive pediatric renal tumor. Intratumoral hemorrhage and tumor rupture are considered as oncologic emergencies, requiring a quick and appropriate response. Herein, we report the case of an 11-year-old boy, who visited our hospital with abdominal distension that started a month earlier. Computed tomography (CT) revealed a tumor in the left kidney (size: 200 mm), and a diagnosis of CCSK was established with a biopsy. Chemotherapy was initiated to shrink the large and densely vascularized tumor before surgical removal. Two days after initiating chemotherapy, the patient developed abdominal and back pain, anemia, and hypotension. The CT scan showed intratumoral bleeding. Emergency transcatheter arterial embolization (TAE) was performed to control the bleeding. Three tumor feeding vessels were identified: an ascending branch from the celiac artery, an intermediate branch from the left renal artery, and a descending branch from the inferior mesenteric artery, of which the intermediate and descending branches were large and bleeding profusely; therefore, the intermediate branch was injected with ethanol and the descending branch was subjected to gel-foam embolization. Chemotherapy was resumed, and the patient's condition stabilized gradually. The tumor began to shrink, and subsequent chemotherapy progressed well. In week 12 of chemotherapy, the patient underwent tumor resection and left nephrectomy. Postoperative chemotherapy was completed without complications, and there was no recurrence during a 6-year follow-up. Therefore, TAE can effectively control intratumoral bleeding in pediatric solid tumors and consequently prevent an unnecessary high-risk open surgical procedure.

Neoadjuvant transcatheter arterial chemoembolization and systemic chemotherapy for treatment of clear cell sarcoma of the kidney in children

BACKGROUND

Clear cell sarcoma of the kidney (CCSK) is a rare and aggressive malignant renal tumor. We describe our experience with neoadjuvant transcatheter arterial chemoembolization (TACE) and systematic chemotherapy for the treatment of advanced CCSK in children.

METHODS

Between January 2010 and December 2016, seven patients (3 boys and 4 girls; median 2.2 years) with advanced CCSK received preoperative TACE of renal artery and systemic chemotherapy. The chemoembolic emulsion for TACE consisted of cisplatin, pirarubicin, vindesine, and iodized oil. Preoperative systemic chemotherapy with vindesine, ifosfamide, and etoposide was administered three weeks after TACE. Nephrectomy was performed three weeks after systemic chemotherapy. After surgery, patients received radiotherapy and postoperative chemotherapy.

RESULTS

No cardiotoxicity, renal insufficiency, or hepatic dysfunction was found in any patients. Grade II-III marrow suppression developed in four patients. One patient with tumor progress during neoadjuvant therapy failed to successfully undergo surgery and died. Six patients underwent nephrectomy after neoadjuvant therapy. Median follow-up period was 49.5 months (range, 11-83 months). Five patients have recurrence-free survival. One patient is still in postoperative chemotherapy after nephrectomy, radiotherapy and thoracoscopic resection of lung metastases.

CONCLUSIONS

Neoadjuvant TACE and systemic chemotherapy appeared to be feasible in the treatment of advanced CCSK in this pilot study.

THE TYPE OF STUDY

A case series with no comparison group.

LEVEL OF EVIDENCE

Level IV.

A report of renal artery embolization for hematuria facilitating neoadjuvant chemotherapy in an unresectable malignant renal rhabdoid tumor

Malignant rhabdoid tumor (MRT) of the kidney is a rare pediatric tumor characterized by its aggressive nature and chemoresistance. Our patient had MRT of the right kidney with tumor thrombus in the renal vein, inferior vena cava, and right atrium. He developed transfusion-resistant hematuria. This was successfully controlled with right renal artery embolization allowing completion of his neoadjuvant chemotherapy. He then underwent complete resection of the tumor and thrombus avoiding cardiopulmonary bypass.

A gel-forming poly-L: -guluronic acid produced from no guluronate-rich marine algae using new hydrolysis method: test for endovascular embolization

To prepare a gel-forming poly-L-guluronic acid (Poly-G) from no guluronate-rich Laminaria japonica, a new hydrolysis method was employed with a lower HCl concentration (0.025-0.15 M) and a shorter treatment time (5 min). The Poly-Gs were set to measure purity, presence of poly-L-guluronic block, molecular weight distribution, polymer yield, viscosity, and compressive gel strength. Finally, the Poly-G was tested to embolize the renal vascular system by using a rabbit model and angiography. Optimized Poly-G could be selected with respect to wt% concentration, polymer yield, gel-forming stability, viscosity, and gel strength as an endovascular embolizing agent. Overall, 0.4-0.6% of 0.03 M-Poly-G obtained from acid treatment with 0.03 M of HCl had molecular weights greater than 80 kDa, and the best gelling capacity with an injectable viscosity (30-120 cP). It was successfully delivered into the vascular bed of a rabbit kidney and was shown angiographically to embolize the renal vascular system.

Chitosan-coated alginate microspheres for embolization and/or chemoembolization:In vivostudies

In this study, chitosan-coated alginate microspheres were prepared by the ionic complexation of alginate and chitosan biopolymers to use in embolization and/or chemoembolization studies. Biopolymeric microspheres were prepared by the ionic gelation technique of alginate with a suitable divalent cation (i.e. CaCl2) in a suspension medium composed of mineral oil and petroleum ether including emulsifier (i.e. Tween-80) and then obtained microspheres were coated with chitosan in an aqueous chitosan solution while the medium was magnetically stirred. The obtained microspheres are in the size range of 100-400 microm and they can be prepared as required by changing the preparation conditions (i.e. stirring rate, concentration of biopolymers, molecular weight and concentration of chitosan, etc.). In the in vivo studies, New Zealand rabbits were used as the test animals. Both complete and partial embolization of the kidney were achieved by using the microspheres. The renal angiograms obtained before/after embolization and the histopathological observations showed the feasibility of the chitosan-coated alginate microspheres as an alternative embolization and/or chemoembolization agent.

Preparation and characterization of Mitomycin-C loaded chitosan-coated alginate microspheres for chemoembolization

Mitomycin-C loaded and chitosan-coated alginate microspheres were prepared for use in chemoembolization studies. In this respect, first alginate microspheres were prepared by using a spraying method using an extrusion device with a small orifice and following suspension cross-linking in an oil phase. Chitosan-coating onto the alginate microspheres was achieved by polyionic complex formation between alginate and chitosan. CaCl(2) was used as a cross-linker for alginate microspheres. The obtained chitosan-coated alginate microspheres were spherical shaped and approximately 100-400 microm average size. The microspheres were evaluated based on their swellability and the swelling ratio was changed between 50-280%. CaCl(2) concentration, stirring rate, chitosan molecular weight, chitosan concentration and time for coating with chitosan were selected as the effective parameters on microsphere size and swelling ratio. Equilibrium swellings were achieved in approximately 30 min. On the other hand, chitosan molecular weight, chitosan concentration and time for coating with chitosan were found as the most effective parameters on both drug loading ratio and release studies. Maximum drug loading ratio of 65% was achieved with high molecular weight (HMW) chitosan, highest chitosan concentration (i.e. 1.0% v/v) and shortest time for coating with chitosan (i.e. 1 h) values.

Emergent embolisation to control severe haematuria in Wilms' tumour

Wilms' tumour commonly presents with an abdominal mass and gross haematuria. Here, we present the novel application of paediatric renal arterial embolisation to control life-threatening haematuria in Wilms' tumour.

Studies on alginate-chitosan microcapsules and renal arterial embolization in rabbits

Spherical and well-dispersed alginate-chitosan microcapsules, with a mean diameter of 77.28+/-0.93 microm (n=3), were prepared by the emulsification-gelation method. Adriamycin hydrochloride (ADM) was used as a model drug to investigate the drug loading capacity and release characteristics of the microcapsules. The drug/carrier ratio and chitosan concentration influenced the encapsulation efficiency of adriamycin. The adriamycin release from microcapsules was obviously different in 0.1 mol/l HCl from that in phosphate-buffered saline (PBS, pH 7.4). The drug was completely and rapidly released in 0.1 mol/l HCl, while it showed a sustained release after a burst release in PBS. The increase in chitosan concentration had no effect on adriamycin release in PBS. Using sulforhodamin B (SRB)-staining survival assay, the inhibition of adriamycin alginate-chitosan microcapsules (ADM-ACM) to different cancer cell lines (human BGC-823 cells, Bel-7402 cells and Hela cells) in vitro was determined. The inhibitory rate of ADM-ACM suspension to the three cell lines significantly outran that of ADM solution, no matter at high or low concentration. The effects of blank alginate-chitosan microcapsules (BACM) on renal arterial embolization were examined with transcatheter arterial embolization in rabbits. The angiogram and histopathological results indicated the blank microcapsules had excellent short- and long-term effects on renal arterial embolization.