Kypho-IORT - a novel approach of intraoperative radiotherapy during kyphoplasty for vertebral metastases

Abstract

BackgroundInstable and painful vertebral metastases in patients with progressive visceral metastases present a common therapeutic dilemma. We developed a novel approach to deliver intraoperative radiotherapy (IORT) during kyphoplasty and report the first treated case.Methods/Results60 year old patient with metastasizing breast cancer under chemotherapy presented with a newly diagnosed painful metastasis in the 12th thoracic vertebra. Under general anaesthesia, a bipedicular approach into the vertebra was chosen with insertion of specially designed metallic sleeves to guide the electron drift tube of the miniature X-ray generator (INTRABEAM, Carl Zeiss Surgical, Oberkochen, Germany). This was inserted with a novel sheet designed for this approach protecting the drift tube. A radiation dose of 8 Gy in 5 mm distance (50 kV X-rays) was delivered. The kyphoplasty balloons (KyphX, Kyphon Inc, Sunnyvale) were inflated after IORT and polymethylmethacrylate cement was injected. The whole procedure lasted less than 90 minutes.ConclusionIn conclusion, this novel, minimally invasive procedure can be performed in standard operating rooms and may become a valuable option for patients with vertebral metastases providing immediate stability and local control. A phase I/II study is under way to establish the optimal dose prescription.

Use of parallel‐plate ionization chambers in reference dosimetry of NOVAC and LIAC® mobile electron linear accelerators for intraoperative radiotherapy: a multi‐center survey

“…IORT is evidence‐based for pelvic and abdominal malignancies where normal bowel limits the dose that can be delivered with EBRT . Recently, this technique has also been deployed in connection with breast cancer as a replacement for whole breast EBRT in selected women suitable for breast‐conserving therapy as well as other malignancies …”

“…5 Recently, this technique has also been deployed in connection with breast cancer as a replacement for whole breast EBRT in selected women suitable for breast-conserving therapy [6][7][8] as well as other malignancies. 5,9,10 Currently, IORT treatments are being performed using both conventional linear accelerators (linacs) 11 and dedicated equipment. The latter include mobile electron linacs 12 and miniaturized low-energy X-ray machines.…”

Operative Therapie von Wirbelsäulenmetastasen urologischer Tumoren

“…Die Kombination von Ballonkyphoplastie mit einer intraoperativen Radiotherapie (IORT) stellt eine neue Therapieform dar [38,39]. Hierbei wird eine mobile Strahlungsquelle in den befallenen Wirbelkörper eingebracht und dadurch eine intravertebrale Bestrahlung über 2-4 min durchgeführt.…”

“…Es kann somit eine fokale Herddosis appliziert werden, die bei perkutaner Bestrahlung typischerweise nicht erreicht wird. Nach Entfernung der Strahlungsquelle wird anschließend der Kyphoplastieballon eingeführt und die Kyphoplastie mit Auffüllung des Wirbelkör-pers mittels PMMA-Zement abgeschlossen [38]. In einer Pilotstudie zeigte sich für dieses Verfahren eine schnelle Linderung ossärer Schmerzen bei einer extrem niedrigen Rate an Lokalrezidiven; allerdings war die Nachbeobachtungszeit mit 6 Wochen limitiert [40].…”

Electronic brachytherapy—current status and future directions

“…11 Solid spherical applicators were developed to deliver intraoperative radiotherapy (IORT) to the tumour bed for breast cancer, as described below. Further applicators have been designed for gynaecological, skin and kyphoplasty treatments, 12,19,20 but only a few clinical results have been reported. 21,22 The Xoft® Axxent® system (iCAD Inc., Nashua, NH) is a miniature X-ray tube integrated with a cooling sheath into a multilumen catheter, first released in 2006 (Figure 1b).…”