The Importance of Preoperative Endovascular Embolization in Assisting Giant Musculoskeletal Tumor Surgery: A Case Series of A Tertiary Center in Indonesia

Introduction

Musculoskeletal malignancy is a global health burden with a significant reduction in quality of life, independence, and functional status. Traditional treatments for musculoskeletal malignancies involve medical management, surgery, and radiotherapy. However, it is often limited by poor functional status and resectability.¹

Arterial embolization is a minimally invasive treatment that occludes blood vessels supplying pathological tissue, offering minimally invasive therapeutic options such as preoperative treatment, palliative therapy, or even standalone therapy for some tumors.² As the conventional therapy for bone and soft-tissue tumors requires resection with significant blood loss, endovascular embolization is an emerging therapy with promising outcomes and limited complications.¹ Previous study by Kedra et al. (2023) showed that selective transarterial embolization of the tumor beds performed using liquid embolic agents, ethylene vinyl alcohol copolymer, gelatin sponge (Gelfoam^® or Embocube^®), and/or coils reduces intraoperative blood loss and improves functional outcomes.³

Although it is a promising approach to treat giant musculoskeletal tumors, there are limited studies on its treatment, especially in Southeast Asian countries such as Indonesia. This case report details the importance of endovascular embolization prior to a musculoskeletal tumor with an increased risk of perioperative bleeding. This case is reported according to the CARE (case report guidelines) 2017 criteria.⁴

Case report

First case

A 22-year-old man was referred to the Interventional Radiology department for preoperative endovascular embolization a day prior to resection of a giant cell tumor with an aneurysmal bone cyst in the proximal right humerus. The tumor was initially as small as a tennis ball but eventually grew larger until it became as large as the whole upper shoulder. Based on physical examination, a 17 × 16 × 9 cm mass was measured on the upper right humerus. Preoperative magnetic resonance imaging (MRI) with gadolinium contrast revealed heterogeneous lytic lesions in the epimetaphysis until the mid-diaphysis right humerus, lobulated, septate with malignant characteristic expanded, and pushing the muscle component around the lesion in all directions. Because the surgery was thought to have massive bleeding, preoperative embolization was performed. During the procedure, hypervascularity was found to be supplied by the branches of the axillary, brachial, and deep brachial arteries. Embolization was performed with a Vertebral 5F catheter, super selectively with Progreat 2.7 microcatheter, and Gelfoam^®, following which the hypervascularity was no longer found. Tumor resection following the procedure was successfully performed, with 1,500 mL of blood loss. The patient was discharged seven days after surgery. Six months after the surgery, the patient had already visited for a follow-up examination, with no recurrence noted (Figure 1).

Figure 1. A 22-year-old man with giant cell tumor and aneurysmal bone cyst in the proximal right humerus

(A) preoperative right shoulder X-ray AP position (B) preoperative T1-weighted MRI with Gadolinium contrast administration (C) angiography following procedure (D) angiography post embolization procedure.

Second case

A 53-year-old man was referred to the Interventional Radiology department for preoperative endovascular embolization a day before resection of a giant right femoral mass. The mass measured 30 × 17 cm and was located along the right femur. Preoperative MRI examination revealed a 30x17 cm soft-tissue mass with a fat component located intramuscularly in the vastus medialis right femur, encasing the great saphenous vein, with no infiltration to the bone. During the procedure, a hypervascular tumor stain with a feeding artery from the superficial femoral artery was observed. Hypervascularity was absent following embolization with vertebral catheters, Progreat^®, and Gelfoam^®. Tumor resection was performed a day after the procedure, with only 100 mL of bleeding. The patient was then discharged seven days following after surgery. Histopathological examination revealed an atypical lipomatous tumor. Six months afterward, no recurrence was observed (Figure 2).

Figure 2. A 53-year-old man with right femoral atypical lipomatosis tumor

(A) preoperative right femur X-ray AP Position (B) preoperative T1- weighted Fat Suppressed MRI with Gadolinium contrast administration coronal view (C) Intraoperative picture (D) angiography before procedure (E) angiography after embolization procedure.

Third case

A 41-year-old man was referred for preoperative endovascular embolization a day prior to resection of a right femoral liposarcoma. Prior to the surgery, he had already undergone contrast MRI examination, which revealed a mixed heterogeneous mass with fat and soft tissue components involving all posterior and middle compartment femur muscle groups through almost all anterior muscle groups with no infiltration to the femur bone. Angiography revealed a hypervascular tumor stain with a feeding artery originating from the deep circumflex iliac artery. Following embolization with vertebral catheters, Progreat^®, Gelfoam^®, and bearing nsPVA^® particles 355-500 μm, no hypervascularity was observed. Subsequently, the tumor was excised and 700 mL of blood was lost. The patient was then discharged on postoperative day 10. No recurrence was noted during the six months postoperative follow-up visit (Figure 3).

Figure 3. A 41-year-old man with right femoral liposarcoma

(A) preoperative right femur X-ray AP position (B) preoperative T1-weighted fat suppressed with mixed Gadolinium contrast enhancement (C) intraoperative picture (D) angiography before procedure (E) angiography evaluation after embolization procedure.

Discussion

As a growing technique in Interventional Radiology, endovascular embolization involves selective endovascular occlusion of blood vessels supplying areas of pathological tissue with mechanical devices or embolic agents, even using chemotherapeutic drugs. This treatment shall then be used to alleviate pain, reduce tumor size, and reduce preoperative bleeding.² Previous systematic review by Papalexis et al. (2024) showed that embolization is gaining recognition as a routine treatment for various oncologic musculoskeletal cases, as most of the tumors have high vascularity due to abnormal development of blood vessels, especially in metastatic cases.²

A review by Greates et al. (2020) showed that successful embolization was defined as more than 70% of obliteration of vascularity, which was achieved in about 36-75% of the cases.⁵ Following successful embolization, reduced intraoperative blood loss and blood transfusion were shown, reducing the intraoperative and postoperative complications, especially in long bones such as the femur and humerus, which are expected to have more substantial bleeding.⁵ In our cases, all of the patients had primary tumor in the long bone; thus, preoperative endovascular embolization was chosen.

Post-embolization syndrome, which is defined as fever, nausea, vomiting, and increased ischemic pain, is one of the most common side effects with an incidence of approximately 20% and is thought to be self-limiting.² In our cases, there were no similar symptoms noted following the procedure. This indicates that the procedure is safe and may be an alternative to conventional surgery.

Currently, there are limited reports on endovascular embolization as a preoperative adjunct for giant musculoskeletal tumors in Southeast Asia. Wong et al. (2020) showed that endovascular embolization was use preoperatively in order to reduce blood loss in musculoskeletal tumors cases in Singapore.⁶ Rizqi et al. (2022) also showed in her case report that the treatment has been used in Indonesia for metastatic bone disease of renal cell carcinoma case.⁷ However, there are currently no larger study about the procedure for musculoskeletal tumors adjunct in Indonesia.

Conclusions

Preoperative embolization may significantly reduce intraoperative blood loss in patients with large musculoskeletal tumors, represented by the absence of hypervascularity following endovascular embolization. Due to reduced vascularization, safer dissection, fewer transfusions, and fewer complications may be obtained.

Consent

Written informed consent for the publication of the data was obtained from the patients.