Embolization of Musculoskeletal Tumors

Pre-Operative Embolisation of Musculoskeletal Tumours - A Single Centre Experience

Introduction

The management of musculoskeletal tumours is complex and requires a multi-disciplinary approach. Preoperative embolisation can be often employed to reduce intra-operative blood loss and complication rates from surgery. We report our experience with the safety, technical success and efficacy of pre-operative embolisation in musculoskeletal tumours.

Materials and Methods

Thirteen consecutive patients who underwent pre-operative embolisation of a musculoskeletal tumour followed by surgical intervention at our institution from May 2012 to January 2016 were enrolled into the study. Patient demographics, tumour characteristics, embolisation techniques and type of surgery were recorded. Technical success of embolisation, amount of blood loss during surgery and transfusion requirements were estimated.

Results

There were five female and eight male patients who underwent pre-operative embolisation during the study period. The age ranged between 16 to 68 years, and the median age was 54. Technical success was achieved in all patients. Mean intra-operative blood loss was 1403ml, with a range of 150ml to 6900ml. Eight patients (62%) required intra-operative blood products of packed red blood cells and fresh frozen plasma. No major complications occurred during embolisation.

Conclusion

Pre-operative trans-arterial embolisation is feasible and safe for a variety of large and hypervascular musculoskeletal tumours. Our small series suggests that preoperative embolisation could contribute to the reduction of the intra-operative and post-operative blood product transfusion. It should be considered as a pre-operative adjunct for major tumour resections with a high risk of bleeding. The use of the haemoglobin gap complemented the assessment of perioperative blood loss.

Third-Ray and Capitate Resection with Limited Midcarpal Fusion for Recurrent Giant Cell Tumor: A Case Report

CASE

We describe a 23-year-old man who had multiple recurrences of a giant cell tumor (GCT) of the third metacarpal. Initial treatments consisted of curettage without the use of an adjuvant and bone-grafting. At the time of the latest recurrence, the lesion had extended into the capitate and the trapezoid. Treatment included third-ray resection and limited midcarpal fusion. No local recurrence was identified at more than 1 year after surgery.

CONCLUSION

GCTs of the hand should be aggressively treated, but care should be taken to preserve function whenever possible.

The evolution of pre-operative spine tumour embolization

Pre-operative spine tumour embolization is a useful adjunct to minimize operative complications and blood loss during complex resections. While the efficacy of this procedure has been well studied, relatively little is documented regarding how to optimize technical parameters for tumour characteristics. This pictorial case series seeks to review our centre's experience over the last decade in using a range of embolization techniques. As experience with this procedure has matured, we propose an approach based on the patient's vascular anatomy and tumour angioarchitecture. This includes the use of coils as protective barriers rather than primary embolics; particle embolization to permeate fine capillary networks; consideration for liquid embolic agents in the presence of large caliber tumour vessels with associated arteriovenous shunting; and percutaneous intralesional embolization when endovascular access is insufficient to achieve the desired outcome. In many cases, a combination of these methods is needed, and close communication with the surgeon ensures the best outcome. Despite these advances, continued work is needed to determine how to optimize complete devascularization, and thus surgical benefit, while safely sparing critical neuroanatomical structures.

Advances in Biomaterials and Technologies for Vascular Embolization

Minimally invasive transcatheter embolization is a common nonsurgical procedure in interventional radiology used for the deliberate occlusion of blood vessels for the treatment of diseased or injured vasculature. A wide variety of embolic agents including metallic coils, calibrated microspheres, and liquids are available for clinical practice. Additionally, advances in biomaterials, such as shape-memory foams, biodegradable polymers, and in situ gelling solutions have led to the development of novel preclinical embolic agents. The aim here is to provide a comprehensive overview of current and emerging technologies in endovascular embolization with respect to devices, materials, mechanisms, and design guidelines. Limitations and challenges in embolic materials are also discussed to promote advancement in the field.

Embolization of hypervascular bone metastases reduces intraoperative blood loss: a case-control study

BACKGROUND

Small case series suggest that preoperative transcatheter arterial embolization minimizes bleeding and facilitates surgery for hypervascular metastatic bone tumors. However, control groups would make our confidence in clinical recommendations stronger, but small patient numbers make prospective trials difficult to conduct on this topic.

QUESTIONS/PURPOSES

In this case-control study, we asked whether (1) patients who undergo embolization have less estimated blood loss and/or shorter operative time than patients who do not have embolization; (2) larger tumor size, greater initial tumor vascularity, and longer interval from embolization to surgery are associated with greater estimated blood loss and packed red blood cell transfusion volume; and (3) embolization does not affect renal function in patients with normal preoperative renal function.

METHODS

We retrospectively reviewed records of patients with hypervascular bone metastases treated at our institution between 1998 and 2008. Twenty-seven patients with renal cell carcinoma and 12 with thyroid carcinoma who underwent embolization before 41 surgical procedures were matched to 41 patients who did not have embolization with respect to age, diagnosis, tumor size and potential vascularity, and procedure type; matching was performed without knowledge of outcomes. In univariate and multivariate analyses, age, tumor size, use of embolization, surgery type and risk, embolization-to-surgery interval, and degree of devascularization were evaluated for correlations with estimated blood loss, packed red blood cell transfusion volume, operative time, and postembolization renal function.

RESULTS

Overall, patients who had embolization had less mean estimated blood loss (0.90 versus 1.77 L; p = 0.002), packed red blood cell transfusion volume (2.15 versus 3.56 U; p = 0.020), and operative time (3.13 versus 3.91 hours; p < 0.001). Larger tumor size correlated with greater estimated blood loss (r = 0.451; p = 0.003), packed red blood cell transfusion volume (r = 0.50; p = 0.002), and operative time (r = 0.595; p < 0.001). Neither the interval for embolization to surgery nor the degree of devascularization correlated with estimated blood loss or transfusion volume. In open rodding with intralesional curettage, transcatheter arterial embolization was associated with reduced estimated blood loss, transfusion volume, and operative time. Packed red blood cell transfusion volume was not reduced by embolization in intramedullary nailing procedures with the patient numbers available. Among patients with normal preoperative renal function who had embolization, creatinine levels remained normal. Mild transient, reversible renal function change occurred in one patient with preoperatively abnormal renal function.

CONCLUSIONS

This study suggests that preoperative embolization probably reduces estimated blood loss, particularly for large tumors and during open femoral procedures.

Analysis of surgical site infection after musculoskeletal tumor surgery: risk assessment using a new scoring system

Surgical site infection (SSI) has not been extensively studied in musculoskeletal tumors (MST) owing to the rarity of the disease. We analyzed incidence and risk factors of SSI in MST. SSI incidence was evaluated in consecutive 457 MST cases (benign, 310 cases and malignant, 147 cases) treated at our institution. A detailed analysis of the clinical background of the patients, pre- and postoperative hematological data, and other factors that might be associated with SSI incidence was performed for malignant MST cases. SSI occurred in 0.32% and 12.2% of benign and malignant MST cases, respectively. The duration of the surgery (P = 0.0002) and intraoperative blood loss (P = 0.0005) was significantly more in the SSI group than in the non-SSI group. We established the musculoskeletal oncological surgery invasiveness (MOSI) index by combining 4 risk factors (blood loss, operation duration, preoperative chemotherapy, and the use of artificial materials). The MOSI index (0-4 points) score significantly correlated with the risk of SSI, as demonstrated by an SSI incidence of 38.5% in the group with a high score (3-4 points). The MOSI index score and laboratory data at 1 week after surgery could facilitate risk evaluation and prompt diagnosis of SSI.

A comparison of cyst wall curettage and en bloc excision in the treatment of aneurysmal bone cysts

BACKGROUND

The recurrence rate after aneurysmal bone cyst (ABC) treatment is quite high despite its benign nature. In ABC therapy, curettage is the treatment of choice; en bloc excision results in a lower recurrence rate, but more extensive reconstructive surgery is needed with associated morbidity. The aim of the present study was to compare the outcomes of the two treatment options.

METHODS

A retrospective analysis was performed on 26 patients treated for ABCs: 16 by curettage and 10 by en bloc excision. Each lesion was classified according to Enneking and patients were followed up for a mean time of 9.2 years. On follow-up, radiological examination and functional assessment (range of motion, muscle strength) were performed. Recurrence was defined as the presence of an osteolytic lesion, especially one with a tendency to grow.

RESULTS

On follow-up, the following symptoms were more prevalent in the en bloc excision group compared to the curettage group: pain (en bloc 20% versus curettage 6.25%), limb length differences (en bloc 20% versus curettage 12.5%), reduced range of motion (en bloc 20% versus curettage 6.25%) and muscle strength impairment (en bloc 50% versus curettage 31.2%); however, the differences were not statistically significant (P >0.05). In the curettage group, two cases of postoperative complications and two cases of recurrence were seen, while in the en bloc excision group one case of complications was noted.

CONCLUSIONS

Curettage is a standard procedure in ABC management. En bloc excision is another option, albeit more technically demanding, that may be considered in recurrent lesions with extensive bone destruction or for cysts in an expendable location.

Preoperative embolization of primary spinal aneurysmal bone cysts by direct percutaneous intralesional injection of n-butyl-2-cyanoacrylate

Aneurysmal bone cysts (ABCs) are highly vascular lesions often referred for preoperative transarterial embolization. However, accessible arterial pedicles do not always exist. Two cases are presented of pediatric patients with spinal ABCs in which preoperative embolization was performed by percutaneous injection of up to 31 mL of liquid embolic agent (1:7 ratio, n-butyl-2-cyanoacrylate [n-BCA] to ethiodized oil). Total estimated surgical blood loss was 1,000 mL in one case and 3,650 mL in the other case, which occurred during the extensive anterior and posterior approaches required to remove the massive ABCs. Direct percutaneous injection of n-BCA is a technically simple and efficient adjunct to surgical resection with the aim to reduce intraoperative blood loss.

Preoperative and therapeutic embolization of extremities of bone and soft tissue tumors

Embolization of bone and soft tissue tumors has a broad range of indications, from curative treatment to palliation. The main purpose of embolization is to occlude as much of the tumor blood supply as possible. The outcome ranges from complete tumor devascularization and necrosis to degrees of ischemia and hypovascularity. Thus, the tumor will shrink, bleeding will be reduced, borders between the tumor and surrounding tissue will become clear, and resection will be easier. The purpose of this study was to correlate the effectiveness of preoperative embolization with the blood loss and transfusion requirement during surgery for bone or soft tissue tumors.

The clinical evaluation of bone tumors

Bone tumors are uncommon clinical entities that are often a source of diagnostic and therapeutic uncertainty. Evaluating these lesions starts with a patient history and physical examination Imaging then begins with radiographs, followed by advanced imaging modalities, such as magnetic resonance imaging, computed tomography, or bone scan. Biopsy can be performed to establish histologic diagnosis by either closed or open means. Treatment options range from observation to wide resection with reconstruction or amputation. Surveillance schedules vary depending on the type of tumor that is being treated. An algorithm for the evaluation, work-up, and diagnosis of bone tumors is presented.

Selective arterial embolisation for bone tumours: experience of 454 cases

PURPOSE

The authors present the experience of a single institution with selective arterial embolisation for primary and metastatic bone tumours.

MATERIALS AND METHODS

A total of 365 patients were treated with 454 embolisation procedures from December 2002 to April 2010. Embolisation was the primary treatment for benign bone tumours, adjuvant treatment to surgery for benign and malignant bone tumours and palliative treatment for bone sarcomas and metastases. Indications for repeat embolisation included pain or imaging evidence of progressive disease: 105 patients had repeat embolisation at the same location at an interval of 1-3 months; 260 patients had one embolisation, 78 had two and 29 had three or more. In all patients, N-2-butyl cyanoacrylate (NBCA) in 33% lipiodol was the embolic agent used.

RESULTS

A total of 419 of the 454 embolisations (93%) were technically successful. In 35 cases, embolisation was not feasible because of poor lesion vascularisation (21 patients with bone metastases and two with aneurysmal bone cysts), origin of the Adamkiewicz artery in the embolisation field (four patients with bone metastases and one with aneurysmal bone cyst), atheromatosis and arteriosclerosis (five patients with bone metastases) and anatomical and technical problems such as small-calibre vessels, many branches and acute vessel angles (two patients with bone metastases). A clinical response was achieved in 406 of the 419 procedures (97%), and no response in 13 procedures in patients with pelvis and sacrum tumours. Complications included postembolisation syndrome in 81 patients (22%), transient paraesthesias in 41 (11%), skin breakdown and subcutaneous necrosis at the shoulder and pelvis in five (1.4%) and paresis of the sciatic nerve in one (0.3%).

CONCLUSIONS

We recommend embolisation as primary or palliative treatment or an adjunct to surgery for tumours of variable histology. Strict adherence to the principles of transcatheter embolisation is important. Arteries feeding the tumour and collaterals must be evaluated carefully and catheterised superselectively to protect the normal tissues. NBCA is considered the most appropriate embolic agent for small-vessel occlusion without major complications.

Does point of care prothrombin time measurement reduce the transfusion of fresh frozen plasma in patients undergoing major surgery? The POC-OP randomized-controlled trial

Background

Bleeding is a frequent complication during surgery. The intraoperative administration of blood products, including packed red blood cells, platelets and fresh frozen plasma (FFP), is often live saving. Complications of blood transfusions contribute considerably to perioperative costs and blood product resources are limited. Consequently, strategies to optimize the decision to transfuse are needed.

Bleeding during surgery is a dynamic process and may result in major blood loss and coagulopathy due to dilution and consumption. The indication for transfusion should be based on reliable coagulation studies. While hemoglobin levels and platelet counts are available within 15 minutes, standard coagulation studies require one hour. Therefore, the decision to administer FFP has to be made in the absence of any data. Point of care testing of prothrombin time ensures that one major parameter of coagulation is available in the operation theatre within minutes. It is fast, easy to perform, inexpensive and may enable physicians to rationally determine the need for FFP.

Methods/Design

The objective of the POC-OP trial is to determine the effectiveness of point of care prothrombin time testing to reduce the administration of FFP. It is a patient and assessor blind, single center randomized controlled parallel group trial in 220 patients aged between 18 and 90 years undergoing major surgery (any type, except cardiac surgery and liver transplantation) with an estimated blood loss during surgery exceeding 20% of the calculated total blood volume or a requirement of FFP according to the judgment of the physicians in charge. Patients are randomized to usual care plus point of care prothrombin time testing or usual care alone without point of care testing. The primary outcome is the relative risk to receive any FFP perioperatively. The inclusion of 110 patients per group will yield more than 80% power to detect a clinically relevant relative risk of 0.60 to receive FFP of the experimental as compared with the control group.

Discussion

Point of care prothrombin time testing in the operation theatre may reduce the administration of FFP considerably, which in turn may decrease costs and complications usually associated with the administration of blood products.

Trial registration

NCT00656396

Use of intra-arterial chemotherapy and embolization before limb salvage surgery for osteosarcoma of the lower extremity

We report our experience with the use of intra-arterial chemotherapy and embolization before limb salvage surgery in patients with osteosarcoma of the lower extremity. We evaluated the effect of this procedure on the degree of tumor necrosis and on the amount of blood loss during surgery. We reviewed the medical records of all patients who received intra-arterial chemotherapy and embolization before undergoing limb salvage surgery for osteosarcoma of the lower extremity at our institution between January 2003 and April 2008. Patient demographic, tumor characteristics, treatment details, postembolization complications, and surgical and pathological findings were recorded for each patient. We evaluated the operative time, estimated blood loss (EBL), and volume of blood transfusion during surgery and in the postoperative period in all patients in the study group. The same parameters were recorded for 65 other patients with lower extremity osteosarcoma who underwent limb salvage operation at our institution without undergoing preoperative intervention. The study included 47 patients (25 males and 22 females). Angiography showed that the tumors were hypervascular. Intra-arterial chemotherapy and embolization were performed successfully, resulting in a substantial reduction or complete disappearance of tumor stain in all patients. No major complications were encountered. At the time of surgery, performed 3-7 days after embolization, a fibrous edematous band around the tumor was observed in 43 of the 47 patients, facilitating surgery. The goal of limb salvage was achieved successfully in all cases. Percentage tumor necrosis induced by treatment ranged from 70.2% to 94.2% (average, 82.9%). EBL during surgery, EBL from drains in the postoperative period, total EBL, and transfusion volumes were significantly lower in the 47 study patients compared to the 65 patients who underwent surgery without preoperative treatment with intra-arterial chemotherapy and embolization. The mean operative time was also significantly less in the intervention group compared to the nonintervention group (73.2 vs. 88.5 min; p < 0.05). In conclusion, intra-arterial chemotherapy and embolization performed 3 to 7 days before limb salvage surgery in patients with lower extremity osteosarcomas can cause substantial tumor necrosis, reduce the EBL and transfusion requirements during surgery, and induce formation of a false capsule around the tumor, thus facilitating surgical excision of the tumors.