Surgical Treatment of Localized-Type Tenosynovial Giant Cell Tumors of Large Joints: A Study Based on a Multicenter-Pooled Database of 31 International Sarcoma Centers.

BACKGROUND: Localized-type tenosynovial giant cell tumor (TGCT) is a rare, neoplastic disease with only limited data supporting treatment protocols. We describe treatment protocols and evaluate their oncological outcome, complications, and functional results in a large multicenter cohort of patients. A secondary study aim was to identify factors associated with local recurrence after surgical treatment. METHODS: Patients with histologically proven localized TGCT of a large joint were included if they had been treated between 1990 and 2017 in 1 of 31 tertiary sarcoma centers. Of 941 patients with localized TGCT, 62% were female. The median age at initial treatment was 39 years, and the median duration of follow-up was 34 months. Sixty-seven percent of the tumors affected the knee, and the primary treatment at the tertiary center was 1-stage open resection in 73% of the patients. Proposed factors for predicting a first local recurrence after treatment in the tertiary center were tested in a univariate analysis, and those that demonstrated significance were subsequently included in a multivariate analysis. RESULTS: The localized TGCT recurred in 12% of all cases, with local-recurrence-free rates at 3, 5, and 10 years of 88%, 83%, and 79%, respectively. The strongest factor for predicting recurrent disease was a prior recurrence (p < 0.001). Surgical treatment decreased pain and swelling in 71% and 85% of the patients, respectively, and such treatment was associated with complications in 4% of the patients. Univariate and multivariate analyses of the patients who had not undergone therapy previously yielded positive associations between local recurrence and a tumor size of ≥5 cm versus <5 cm (hazard ratio [HR] = 2.50; 95% confidence interval [CI] = 1.32 to 4.74; p = 0.005). Arthroscopy (versus open surgery) was significantly associated with tumor recurrence in the univariate analysis (p = 0.04) but not in the multivariate analysis (p = 0.056). CONCLUSIONS: Factors associated with recurrence after resection of localized-type TGCT were larger tumor size and initial treatment with arthroscopy. Relatively low complication rates and good functional outcomes warrant an open approach with complete resection when possible to reduce recurrence rates in high-risk patients. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Imaging patterns in elastofibroma dorsi.

INTRODUCTION: Elastofibroma dorsi is a rare pseudotumor of the soft tissues. Its clinico-radiologic characteristics lead to a correct diagnosis. MATERIAL AND METHODS: We followed 43 patients with elastofibroma dorsi with a confirmed histological diagnosis or on the basis of typical imaging pattern (ultrasound, CT, MR) confirmed by evolution. RESULTS: Elastofibroma is prevalent in females, its onset occurs around 60 years of age and is most frequently localized in the deep subscapular region (93%), bilateral in 54% of cases. In 7% it was found in an atypical isolated suprascapular region, in 7% it was synchronous to that in the subscapular region. Four ultrasound patterns were detected: Type I (54%) inhomogeneous fasciculated, Type II (22%) inhomogeneous aspecific, Type III (15%) hyperechogeneous, Type IV (9%) hypoechogeneous. Three patterns were detected at CT and MR: Type A (84%) inhomogeneous fasciculated corresponding to Types I and III and partially to Type II ultrasound pattern, Type B (8%) inhomogeneous aspecific corresponding to Type II ultrasound pattern; Type C (8%) homogeneous isodense or isointense to the muscle corresponding to Type IV ultrasound pattern. CONCLUSION: A solid, slow-growing lesion, in the deep periscapular region in females aged between 50 and 60 years, with a typical fasciculated pattern is pathognomonic of elastofibroma dorsi and bilateral location convalidates diagnosis. Ultrasound is sufficient to orientate diagnosis. CT and/or MR are reserved only for non-fasciculated ultrasound patterns, when site is atypical or in candidates for surgery. Biopsy is reserved only in cases where integrated imaging shows a non-fasciculated pattern to differentiate it from other malignant lesions.

Osteoarticular allograft reconstruction of the distal radius after bone tumour resection.

Resection of the distal end of the radius is indicated in the treatment of locally aggressive primary benign and malignant bone tumours. The aim of this study was to evaluate the technique of osteoarticular allograft reconstruction of this bone defect. We analysed 12 patients retrospectively with a minimum follow-up of 2 years (range 26-145 months, median 52 months). Three patients had a malignant tumour and nine had a giant cell tumour. The patients ages ranged from 13 to 65 years. The mean resected length of the radius was 6.6 (range 4-14)cm. Non-union of the osteotomy line was diagnosed 6 months after surgery in one case and needed bone grafting. Distal radio-ulnar joint instability was observed in eight cases. Subchondral bone alterations and joint narrowing were present in all cases but were painful in only one patient. The mean range of motion was 51 degrees of flexion and 37 degrees of extension.

Malignancy in giant cell tumor.

Malignant giant cell tumor is a confusing term that in the past has been used to describe different types of giant cell-rich tumors. We try to clarify this term in this report. We consider two types of malignancy in giant cell tumor of bone: "primary" when it arises in juxtaposition to a benign giant cell tumor and 'secondary' when it arises at the site of a previously treated giant cell tumor. Here we present a case of primary malignancy in giant cell tumor that was initially not recognized as a malignancy. On radiography and histology of frozen sections the lesion had the appearance of a conventional giant cell tumor of bone. After curettage, the permanent histology slides showed areas of highly malignant osteosarcoma juxtaposed to areas of benign giant cell tumor. The patient was treated with chemotherapy and wide resection of the tumor.