Arterial perfusion chemoembolization combined with iodine-125 seeds for stage IIB osteosarcoma: A case report

Abstract

Osteosarcoma is a highly malignant bone tumor that predominantly affects adolescents. Its aggressive nature, complex treatment options and poor prognosis render it a notable concern in oncology. With advancements in therapy for osteosarcoma, neoadjuvant chemotherapy in conjunction with limb-salvage surgery has emerged as the preferred surgical strategy. However, the physical and emotional trauma associated with surgery, along with the adverse side effects of chemotherapy, can be unacceptable to some patients. In recent years, alternative local treatment modalities such as transarterial chemoembolization (TACE) and iodine-125 seed implantation have garnered considerable attention. These techniques show potential in enhancing local tumor control while minimizing systemic toxicity. TACE involves obstructing the blood supply to the tumor while administering localized chemotherapy, resulting in tumor ischemia and necrosis, which is particularly effective for hypervascular tumors. Meanwhile, iodine-125 seeds act as low-energy radiation sources that can effectively target tumor cells while sparing the surrounding healthy tissue. The present study describes a case of osteosarcoma treated with a combination of TACE and iodine-125 seed implantation. The patient, diagnosed with osteosarcoma of the left knee joint, declined surgical intervention. Consequently, a treatment plan involving TACE paired with iodine-125 seed implantation was established. Post-treatment follow-up demonstrated marked pain relief, improved limb function and a notable reduction in tumor volume with decreased bone destruction visible on imaging. Over a follow-up period of 6 years, there were no signs of disease recurrence or distant metastasis, and no notable chemotherapy-related side effects were reported. The quality of life of the patient was markedly improved. The current case illustrates the antitumor efficacy and reduced toxicity of combining TACE with iodine-125 seed implantation in the management of osteosarcoma.

Keywords: TACE; case report; iodine-125 seeds; osteosarcoma.

Figure 1.

Dynamic changes in the degree of left knee swelling and enhanced CT findings before and after surgery. (A) Preoperatively, the left knee joint exhibited notable swelling and was in a passive flexed position. (B) A total of 6 months post-operation, a partial reduction in swelling of the left knee joint was observed, and (C) a total of 11 months post-operation, further subsidence of swelling in the left knee joint was noted. (D) Preoperative enhanced CT image displayed a large soft tissue mass in the left knee joint, measuring ~12.6 cm in maximum diameter and showing inhomogeneous enhancement. (E) A total of 6 months after the operation, enhanced CT imaging indicated that the mass had decreased, with most tumor tissue having been excised, and (F) a total of 11 months post-operation, enhanced CT imaging revealed a further reduction in mass size.

Figure 2.

Process of transcatheter arterial embolization of tumor vessels. (A) Digital subtraction angiography imaging revealed that the tumor located in the lower part of the left thigh was vascularized, showing multiple neovascularizations. (B) The abundant blood supply to the tumor was indicated with white arrows. (C) A microcatheter was strategically used to super-selectively cannulate the tumor blood vessels, with the abundant blood supply to the tumor indicated with white arrows. (D) Following the embolization of the tumor blood vessels with microspheres, the blood supply to the tumor was eliminated.

Figure 3.

After two TACE treatments, enhanced CT follow-up images and process of iodine-125 seed implantation. (A) A notable reduction in tumor blood supply was detected; the red arrow points to the area of bone destruction in the lower part of the left femur, surrounded by mostly necrotic tumor tissue. (B) The white arrow points to the non-enhanced necrotic tumor tissue around the middle part of the left femur, and a decrease in the maximum tumor diameter was detected. (C) Using an 18 G puncture needle, the tumor was penetrated horizontally through the middle sections of the left femur. (D) Using an 18 G puncture needle, the tumor was penetrated horizontally through the left lower femur at the level of the proximal articular surface. (E) Following the successful insertion of iodine-125 seeds, a real-time CT scan was conducted to confirm their optimal distribution within the tumor located in the middle sections of the left femur. (F) Following the successful insertion of iodine-125 seeds, a real-time CT scan was conducted to confirm their optimal distribution within the tumor located on the proximal articular surface of the left lower femoral segment.

Figure 4.

Trends in key indicators during follow-up. (A) MTD was progressively decreased, stabilizing over the course of treatment. (B) NRS pain score was reduced from a preoperative level of 8 to 2. (C) ALP levels were gradually decreased from a preoperative value of 1,752 U/l to the normal range. (D) LDH levels were also diminished from a preoperative level of 735 U/l to within normal limits. MTD, maximum tumor diameter; NRS, Numeric Rating Scale; ALP, alkaline phosphatase; LDH, lactate dehydrogenase.

Figure 5.

Post-treatment biopsy findings. The biopsy revealed extensive necrosis without any residual tumor cells as evidenced by H&E staining. (A) H&E staining showed a notable amount of coagulated necrotic tissue. (B) Most of the fibrotic tissue was identified as collagen degeneration and sclerosis (indicated by red arrows), with a small quantity of muscle tissue observed at the edge (indicated by black arrows). Magnification, ×100. H&E, hematoxylin and eosin.