Preoperative transarterial embolization of vertebral metastases

Abstract

IntroductionSpinal neoplastic lesions of metastatic origin severely affect patient quality of life. Metastasizing tumors show spinal manifestation in 30-70% of cases [2]. Most common primary tumors of vertebral metastases are localized in the breast, lung, prostate and kidney. Surgical intervention with corporectomy, body replacement and stabilization, although controversial, is still the best treatment option for spinal instability, neurological complications and severe pain that cannot be managed conservatively or by local radiation [8,9]. However these extensive surgical procedures are often complicated by massive intraoperative blood loss. Compared with normal vertebrae, tumorous vertebrae show extensive vascularization. The most highly vascularized vertebrae are those with metastases originating from renal cell and thyroid carcinoma [7]. Life-threatening blood losses have been described in cases without preoperative embolization [3,6] Abstract The aim of this study was to evaluate the impact of preoperative devascularization of spinal metastases in relation to the preembolization tumor vascularization degree and in relation to the intraoperative blood loss. Twenty-four patients underwent preoperative transarterial embolization of hypervascular spinal metastases. Each tumor was assigned a vascularization grade (I-III) according to tumor blush after contrast agent injection in the main feeding artery. Embolization was performed with polyvinyl alcohol particles in all patients. Surgical reports were reviewed in terms of estimated blood loss. A mild hypervascularization was found in three patients (group I), medium in six patients (group II) and extensive in 15 patients (group III). In 22 out of 24 patients embolization could be performed with a complete devascularization. In two patients, only partial embolization could be performed, due to the main feeding artery arising from the artery of Adamkiewicz. In patients with complete devascularization the mean intraoperative blood loss was 1,900 ml, whereas in the two patients who were not embolized it was 5,500 ml. Intraoperative blood loss was not correlated to the vascularization grade. Angiography and embolization could be performed in all patients without causing permanent neurologic deficit, skin or muscle necrosis. The surgeons concluded that radical tumor resection after embolization was facilitated. Intraoperative blood loss is not correlated with the pre-interventional vascularization degree, if complete devascularization can be achieved with embolization. Preoperative embolization of vertebral hypervascular tumors is safe, effective and facilitates tumor resection.

Retrospective Analysis of Preoperative Embolization of Spinal Tumors

“…Our data indicate that primary tumors and non-RCC metastasis had mean blood losses similar to those of the literature benchmark of approximately 2 L. [3][4][5][11][12][13] RCCs demonstrated a statistically significantly greater blood loss with EBLs approaching 3 L (P ϭ .009). This value is higher than those reported by others; though after subdividing these cases into those undergoing complete or partial embolization, the mean EBL of completely embolized RCCs approximated a value just under 2 L, an amount comparable with that in these previous studies.…”

“…Multiple case series have demonstrated the effectiveness of preoperative embolization in reducing intraoperative blood loss. [3][4][5][6] While preoperative embolization of RCC has become a standard of care, evidence for embolizing other types of tumors is scarce. Also, technical differences in the embolization procedure, such as the type of embolic agent used, embolizing above and below the tumor, partial-versus-complete embolization, and the time from embolization to surgery, have not been well evaluated.…”

Preoperative spinal tumor embolization: An institutional experience with Onyx

“…[16,17] In a series of 20 vertebral tumors preoperatively embolized by Guzman et al [17], a trend toward decreased blood loss and intraoperative time was demonstrated. Kato et al [18], found the blood loss to be almost half (1128 ml to 520 ml) with the addition of preoperative embolization (with either coils, NBCA, or PVA) for thoracic metastatic epidural tumors in 20 patients.…”

Is it necessary to embolise all spinal metastases from primary renal tumours?

“…3 Current best practice guidelines on the management of metastatic renal carcinoma suggest that, prior to any operative intervention on the metastatic deposits, they should undergo pre-operative embolisation to reduce the risk of catastrophic blood loss at the time of surgery. A lot of the published data on this topic are from the 1970s and 1980s [4][5][6][7] ; in 1974, Benati et al concluded that multiple published case series' had successfully demonstrated the effectiveness of pre-operative embolisation. Success rates throughout the literature vary from 37 to 96%, 3,8 with complication rates varying from 1 to 32%.…”