Is Limb Salvage With Microwave-induced Hyperthermia Better Than Amputation for Osteosarcoma of the Distal Tibia?

Abstract

BackgroundAmputation has been the standard surgical treatment for distal tibia osteosarcoma owing to its unique anatomic features. Preliminary research suggested that microwave-induced hyperthermia may have a role in treating osteosarcoma in some locations of the body (such as the pelvis), but to our knowledge, no comparative study has evaluated its efficacy in a difficult-to-treat location like the distal tibia.QuestionsDoes microwave-induced hyperthermia result in (1) improved survival, (2) decreased local recurrence, (3) improved Musculoskeletal Tumor Society (MSTS) scores, or (4) fewer complications than amputation in patients with a distal tibial osteosarcoma?MethodsBetween 2000 and 2015, we treated 79 patients for a distal tibia osteosarcoma without metastases. Of those, 52 were treated with microwave-induced hyperthermia, and 27 with amputation. Patients were considered eligible for microwave-induced hyperthermia if they had an at least 20-mm available distance from the tumor edge to the articular surface, good clinical and imaging response to neoadjuvant chemotherapy, and no pathologic fracture. Patients not meeting these indications were treated with amputation. In addition, if neither the posterior tibial artery nor the dorsalis pedis artery was salvageable, the patients were treated with amputation and were not included in any group in this study. A total of 13 other patients were treated with conventional limb-salvage resections and reconstructions (at the request of the patient, based on patient preference) and were not included in this study. All 79 patients in this retrospective study were available for followup at a minimum of 12 months (mean followup in the hyperthermia group, 79 months, range 12–158 months; mean followup in the amputation group, 95 months, range, 15–142 months). With the numbers available, the groups were no different in terms of sex, age, tumor grade, tumor stage, or tumor size. All statistical tests were two-sided, and a probability less than 0.05 was considered statistically significant. Survival to death was evaluated using Kaplan-Meier analysis. Complications were recorded from the patients’ files and graded using the classification of surgical complications described by Dindo et al.ResultsIn the limb-salvage group, Kaplan Meier survival at 6 years was 80% (95% CI, 63%–90%), and this was not different with the numbers available from survivorship in the amputation group at 6 years (70%; 95% CI, 37%–90%; p = 0.301).With the numbers available, we found no difference in local recurrence (six versus 0; p = 0.066). However mean ± SD MSTS functional scores were higher in patients who had microwave-induced hyperthermia compared with those who had amputations (85% ± 6% versus 66% ± 5%; p = 0.008).With the numbers available, we found no difference in the proportion of patients experiencing complications between the two groups (six of 52 [12%] versus three of 27 [11%]; p = 0.954).ConclusionsWe were encouraged to find no early differences in survival, local recurrence, or serious compl...

Limb saving surgery for Ewing’s sarcoma of the distal tibia: a case report

“…Use of allografts in Japan is difficult, because a bone bank system has not yet been established. Treated-bone autografts have been associated with good prognosis and postoperative function [ 3 ], but bone strength is necessary. Vascularized fibula grafts are likely to result in bone fusion at an early stage.…”

“…Furthermore, the presence of nerves and blood vessels at this site makes securing safe surgical margins difficult. Thus, amputation or radiotherapy may be the only curative treatment for patients with tumors of the distal tibia [ 3 , 4 ].…”

Clinical Guideline for Microwave Ablation of Bone Tumors in Extremities

“…Recommendation 10: For Large-Sized Bone Tumors in Extremities, Multiple-Antenna Microwave Ablation May Be Useful O wing to high frequency, short wavelength, and shallow penetration depth, medical microwave is generally about 3 cm. To achieve complete ablation of large tumors, multiple-antenna microwave ablation is a safe and effective choice 16,39,41,[54][55][56] . Using microwave antenna arrays is regarded as a safe and effective approach to treating malignant or invasive bone tumors in the limb 54 .…”

“…A common and simple approach to isolating tumor and the surrounding soft tissue is to use a gauze soaked in cooling saline after tumor separation. Continuous use of hypothermic saline can also protect the surrounding soft tissue during ablation 16,42,55,62 . When the tumor is adjacent to the articular surface, circulating cooling saline can be used to cool the articular cavity during microwave ablation to avoid thermal injury of the articular surface cartilage 16,18,56 .…”

“…From the initial stage of treating primary malignant bone tumors, the treatment has also been used to treat metastatic bone tumors, malignant soft tissue tumors, and benign bone tumors; moreover, the operation and operating technology have become increasingly standardized. Microwave ablation can be used as an independent percutaneous minimally invasive treatment for some benign bone tumors and bone metastases 13,14 , or as an auxiliary treatment for hemostasis, tumor inactivation or improving the safety of tumor resection boundary [15][16][17][18][19] .…”