What Are the Results of Limb Salvage Surgery for Primary Malignant Bone Tumor in the Forearm?

Background The forearm primary malignant bone tumor is rare and limb salvage is difficult. The purpose of this study was to analyze epidemiological characteristics of forearm primary malignant bone tumors and to explore oncological and functional results of limb salvage surgery in forearm.Methods 369 patients with primary forearm malignant bone tumors were retrospectively analyzed from 2000 to 2017. There were 266 patients with radius tumor and 46 (17.3%) of them were malignancy, while 103 patients with ulna lesion and 22 (21.4%) of them were malignant tumor. The oncological results, prognostic factors and functional results after limb salvage surgery of forearm malignancy were analyzed.Results A total of 60 patients received limb salvage surgery. Fifty-six patients followed more than 12 months or progressions within 12 months were included in final evaluation. Radius resection was performed in 38 patients and distal radius (25 patients) was most frequent. Ulna resection was performed in 18 patients and proximal ulna (13 patients) was most frequent. The surgical margin contained intracapsular resection in 3 patients, marginal resection in 8 patients and wide resection in 45 patients. The follow-up averaged 72.1 (7-192, median 62.5) months. Local recurrence occurred in 11 patients (19.6%) and distant metastasis occurred in 14 patients (25%). The 5-year recurrence free survival rates was 79.8%. Univariate analysis showed history of unplanned resection, tumor located in ulna, tumor located in proximal forearm and inadequate surgical margin were associated with recurrence. The overall 5-year and 10-year survival rates were 83.5% and 71.7%, respectively. Univariate analysis showed inadequate surgical margin, local recurrence and distant metastasis were associated with death. Forty-two patients were evaluated by MSTS score with an average of (93.0 ± 5.1) %.Conclusions The incidence of radius malignant tumor is higher than that of ulna. The distal radius and proximal ulna are most frequency involved sites. Unplanned resection, tumor located in ulna, tumor located in proximal forearm and inadequate surgical margin are risk factors for local recurrence; local recurrence and distant metastasis are independent prognostic factors of death. The oncology control and function result of limb salvage surgery was satisfactory.