Late Local Recurrence of Bone Giant Cell Tumors Associated with an Increased Risk for Malignant Transformation

Current Concepts in the Treatment of Giant Cell Tumor of Bone: An Update

Curettage is recommended for the treatment of Campanacci stages 1-2 giant cell tumor of bone (GCTB) in the extremities, pelvis, sacrum, and spine, without preoperative denosumab treatment. In the distal femur, bone chips and plate fixation are utilized to reduce damage to the subchondral bone and prevent pathological fracture, respectively. For local recurrence, re-curettage may be utilized when feasible. En bloc resection is an option for very aggressive Campanacci stage 3 GCTB in the extremities, pelvis, sacrum, and spine, combined with 1-3 doses of preoperative denosumab treatment. Denosumab monotherapy once every 3 months is currently the standard strategy for inoperable patients and those with metastatic GCTB. However, in case of tumor growth, a possible malignant transformation should be considered. Zoledronic acid appears to be as effective as denosumab; nevertheless, it is a more cost-effective option. Therefore, zoledronic acid may be an alternative treatment option, particularly in developing countries. Surgery is the mainstay treatment for malignant GCTB.

Giant cell tumor of bone at distal radius suffered more soft tissue recurrence and ultrasonography is effective to detect the soft tissue recurrence

BACKGROUND

Soft tissue recurrence of giant cell tumor of bone (GCTB) is rare. This study aims to provide its prevalence, recurrent locations, risk factors, effective detection methods and a modified classification for this recurrence.

METHODS

Patients with soft tissue recurrence after primary surgery for GCTB were screened from January 2003 to December 2022. General data, recurrence frequency, types according to an original classification (type-I: peripheral ossification; type-II: central ossification; type-III: without ossification), a modified classification with more detailed subtypes (type I-1: ≤ 1/2 peripheral ossification; type I-2: ≥ 1/2 peripheral ossification; type II-1: ≤ 1/2 central ossification; type II-2: ≥ 1/2 central ossification; type III: without ossification), locations, detection methods such as ultrasonography, X-ray, CT or MRI, Musculoskeletal Tumor Society (MSTS) scores were recorded. Multivariate regression analysis was conducted to identify risk factors for recurrence frequency.

RESULTS

A total of 558 recurrent cases were identified from 2009 patients with GCTB. Among them, 32 were soft tissue recurrence. The total recurrence rate was 27.78% (558/2009). Soft tissue recurrence rate was 5.73% among 558 recurrent cases, and 1.59% among 2009 GCTB patients, respectively. After excluding one patient lost to follow-up, 10 males and 21 females with the mean age of 28.52 ± 9.93 (16-57) years were included. The definitive diagnosis of all recurrences was confirmed by postoperative pathology. The interval from primary surgery to the first recurrence was 23.23 ± 26.12 (2-27) months. Eight recurrences occurred from primary GCTB located at distal radius, followed by distal femur (6 cases). Recurrence occurred twice in 12 patients and 3 times in 7 patients. Twenty-seven recurrences were firstly detected by ultrasonography, followed by CT or X-ray (10 cases in each). Types at the first recurrence were 5 cases in type-I, 8 in type-II and 18 in type-III. According to the modified classification, 3 patients in type I-1, 2 in type I-2, 1 in type II-1, 7 in type II-2, and 18 in type III. The mean MSTS score was 26.62 ± 4.21 (14-30). Neither Campanacci grade nor recurrence type, modified classification and other characters, were identified as risk factors.

CONCLUSIONS

Soft tissue recurrence of GCTB may recur for more than once and distal radius was the most common location of primary GCTB that would suffer a soft tissue recurrence. Ultrasonography was a useful method to detect the recurrence. Since no risk factors were discovered, a careful follow-up with ultrasonography was recommended.

Progress on Denosumab Use in Giant Cell Tumor of Bone: Dose and Duration of Therapy

Giant cell tumor of bone (GCTB) is an aggressive non-cancerous bone tumor associated with risks of sarcoma and metastasis. Once malignancy occurs, the prognosis is generally poor. Surgery remains the main treatment for GCTB. Multidisciplinary management is a feasible option for patients wherein surgical resection is not an option or for those with serious surgery-related complications. Denosumab is an anti-nuclear factor kappa B ligand approved for the treatment of postmenopausal women with osteoporosis, bone metastases, and advanced or inoperable GCTB. However, the guidelines for treating GCTB are unclear; its short-term efficacy and safety in inoperable patients have been demonstrated. Lengthier therapies (high cumulative doses) or pre-operative adjuvant therapy may be associated with severe complications and high local recurrence rates. Short-term administration helps attain satisfactory local control and functionality. As a result, lately, the impact of different doses and lengths of treatment on the efficacy of denosumab in GCTB treatment, the incidence of complications, and recurrence rates have gained attention. The efficacy and safety of denosumab against GCTB, its impact on imaging assessment, related complications, and recurrence of GCTB were previously reviewed. For further research direction, this paper reviews the progress of studies evaluating the impact of the dose and duration of denosumab therapy for GCTB.

Outcome of Reoperation for Local Recurrence Following En Bloc Resection for Bone Giant Cell Tumor of the Extremity

En bloc resection is typically performed to treat giant cell tumors of bone (GCTB), particularly when curettage can be challenging owing to extensive bone cortex destruction with soft tissue extension. Few reports have addressed the clinical outcomes after reoperation for local recurrence in patients with GCTB who underwent en bloc resection. In this multicenter retrospective study, we investigated local recurrence, distant metastasis, malignant transformation, mortality, and limb function in patients treated for local recurrence following en bloc resection for GCTB. Among 205 patients who underwent en bloc resection for GCTB of the extremities between 1980 and 2021, we included 29 with local recurrence. En bloc resection was performed for large tumors with soft tissue extension, pathological fractures with joint invasion, complex fractures, and dispensable bones, such as the proximal fibula and distal ulna. Local re-recurrence, distant metastasis, malignant transformation, and mortality rates were 41.4% (12/29), 34.5% (10/29), 6.9% (2/29), and 6.9% (2/29), respectively. The median Musculoskeletal Tumor Society score was 26 (interquartile range, 23–28). The median follow-up period after surgery for local recurrence was 70.1 months (interquartile range, 40.5–123.8 months). Local recurrence following en bloc resection for GCTB could indicate an aggressive GCTB, necessitating careful follow-up.

Clinicopathological and histological analysis of secondary malignant giant cell tumors of bone without radiotherapy

Giant cell tumor of bone (GCTB) is an intermediate bone tumor that rarely undergoes malignant transformation. Secondary malignant GCTB (SMGCTB) is defined as a lesion in which high-grade sarcoma occurs at the site of previously treated GCTB. The present study retrospectively reviewed the medical records of patients with GCTB treated at Okayama University Hospital between April 1986 and April 2020. The clinicopathological and histological features of patients with SMGCTB without prior radiotherapy were investigated. A total of three patients (4%) with SMGCTB were detected, and the tumor sites were the distal ulna, distal femur and sacrum. Two of the patients had been treated with curettage and bone graft, and one had been treated with denosumab. In all cases, the lesions were made up of two components, the conventional GCTB component and the malignant component. The Ki67 labeling index was higher in the malignant components of SMGCTB and metastatic lesions compared with that in primary and recurrent conventional GCTB, or the conventional GCTB component of SMGCTB. Moreover, p53 expression was higher in these same components in patients who underwent curettage and bone grafting; however, there was no difference in the patient that received denosumab treatment. In this patient, clinical cancer genomic profiling revealed loss of CDKN2A, CDKN2B and MTAP expression. All three patients developed distant metastasis. The patients with SMGCTB in the ulna and femur died 13 and 54 months after detection of malignant transformation, respectively. The patient with SMGCTB in the sacrum received carbon-ion radiotherapy to the sacrum and pazopanib; the treatment was effective and the patient was alive at the last follow-up 3 years later. In conclusion, p53 may be associated with malignant transformation in GCTB. Future studies should investigate the association of between denosumab treatment and malignant transformation, as well as molecular targeted therapy to improve the clinical outcomes of SMGCTB.

A Multiparametric Method Based on Clinical and CT-Based Radiomics to Predict the Expression of p53 and VEGF in Patients With Spinal Giant Cell Tumor of Bone

Purpose

This project aimed to assess the significance of vascular endothelial growth factor (VEGF) and p53 for predicting progression-free survival (PFS) in patients with spinal giant cell tumor of bone (GCTB) and to construct models for predicting these two biomarkers based on clinical and computer tomography (CT) radiomics to identify high-risk patients for improving treatment.

Material and Methods

A retrospective study was performed from April 2009 to January 2019. A total of 80 patients with spinal GCTB who underwent surgery in our institution were identified. VEGF and p53 expression and clinical and general imaging information were collected. Multivariate Cox regression models were used to verify the prognostic factors. The radiomics features were extracted from the regions of interest (ROIs) in preoperative CT, and then important features were selected by the SVM to build classification models, evaluated by 10-fold crossvalidation. The clinical variables were processed using the same method to build a conventional model for comparison.

Results

The immunohistochemistry of 80 patients was obtained: 49 with high-VEGF and 31 with low-VEGF, 68 with wild-type p53, and 12 with mutant p53. p53 and VEGF were independent prognostic factors affecting PFS found in multivariate Cox regression analysis. For VEGF, the Spinal Instability Neoplastic Score (SINS) was greater in the high than low groups, p < 0.001. For p53, SINS (p = 0.030) and Enneking stage (p = 0.017) were higher in mutant than wild-type groups. The VEGF radiomics model built using 3 features achieved an area under the curve (AUC) of 0.88, and the p53 radiomics model built using 4 features had an AUC of 0.79. The conventional model built using SINS, and the Enneking stage had a slightly lower AUC of 0.81 for VEGF and 0.72 for p53.

Conclusion

p53 and VEGF are associated with prognosis in patients with spinal GCTB, and the radiomics analysis based on preoperative CT provides a feasible method for the evaluation of these two biomarkers, which may aid in choosing better management strategies.

State of the Art and New Concepts in Giant Cell Tumor of Bone: Imaging Features and Tumor Characteristics

Simple Summary

The 2020 World Health Organization classification of soft tissue and bone tumors classified the giant cell tumor of bone (GCTB) as an intermediate malignant tumor, with locally aggressive behavior and high recurrence rate. Imaging plays a pivotal role in the assessment of GCTB, and this review tries to summarize the main concepts about GCTB histopathogenesis and new biomarkers, describing those GCTB imaging findings which could possibly be explained by tumor molecular alterations. We have illustrated pre-operative imaging features related to prognosis and radiological findings for response evaluation after surgical treatment and denosumab administration. We have also reported the results described in literature regarding the role of radiomics in aiding GCTB diagnosis, predicting possible post-treatment recurrence and providing a quantitative assessment of the response to denosumab treatment.

Abstract

Giant cell tumor of bone (GCTB) is classified as an intermediate malignant tumor due to its locally aggressive behavior, burdened by high local recurrence rate. GCTB accounts for about 4–5% of all primary bone tumors and typically arises in the metaphysis and epiphyses of the long tubular bones. Mutation of gene H3F3A is at the basis of GCTB etiopathogenesis, and its immunohistochemical expression is a valuable method for practical diagnosis, even if new biomarkers have been identified for early diagnosis and for potential tumor recurrence prediction. In the era of computer-aided diagnosis, imaging plays a key role in the assessment of GCTB for surgical planning, patients’ prognosis prediction and post treatment evaluation. Cystic changes, penetrating irregular margins and adjacent soft tissue invasion on preoperative Magnetic Resonance Imaging (MRI) have been associated with a higher rate of local recurrence. Distance from the tumor edge to the articular surface and thickness of unaffected cortical bone around the tumor should be evaluated on Computed Tomography (CT) as related to local recurrence. Main features associated with local recurrence after curettage are bone resorption around the graft or cement, soft tissue mass formation and expansile destruction of bone. A denosumab positive response is represented by a peripherical well-defined osteosclerosis around the lesion and intralesional ossification. Radiomics has proved to offer a valuable contribution in aiding GCTB pre-operative diagnosis through clinical-radiomics models based on CT scans and multiparametric MR imaging, possibly guiding the choice of a patient-tailored treatment. Moreover, radiomics models based on texture analysis demonstrated to be a promising alternative solution for the assessment of GCTB response to denosumab both on conventional radiography and CT since the quantitative variation of some radiomics features after therapy has been correlated with tumor response, suggesting they might facilitate disease monitoring during post-denosumab surveillance.

Effect of Adjuvant Chemotherapy on Localized Malignant Giant Cell Tumor of Bone: A Systematic Review

Simple Summary

The effect of adjuvant chemotherapy on localized malignant giant cell tumors of the bone (GCTB) is unclear. We compared the mortality associated with wide resection compared to wide resection plus adjuvant chemotherapy for localized primary and secondary localized malignant GCTB. Among 745 relevant studies, 9 were included, with 39 and 73 primary and secondary malignant patients. In primary localized malignant GCTB, the mortality rates were 40% (6/15 patients) and 33% (8/24 patients) in the surgery plus adjuvant chemotherapy and surgery-only groups, respectively. The overall pooled odds ratio was 1.07 (p = 0.92). In secondary localized malignant GCTB, the mortality rates were 30.6% (11/36 patients) and 62.2% (23/37 patients) in the surgery plus adjuvant chemotherapy and surgery-only groups, respectively. The overall pooled odds ratio was 0.31 (p = 0.04). The effect of adjuvant chemotherapy remains unclear for primary localized malignant GCTB, but adjuvant chemotherapy improved the survival of patients with secondary localized malignant GCTB.

Abstract

A malignant giant cell tumor of the bone (GCTB) is a rare primary malignant tumor classified as primary or secondary. Wide resection of the primary tumor is recommended for localized malignant GCTB, but the effect of adjuvant chemotherapy is unclear. A systematic review was performed to compare the mortality associated with wide resection with that of wide resection plus adjuvant chemotherapy for primary and secondary localized malignant GCTB. Among the 745 studies identified, 9 were included. A total of 112 cases of localized malignant GCTB were included, with 39 and 73 cases being primary and secondary malignant GCTB. In primary localized malignant GCTB, the mortality rates were 40% (6/15 patients) and 33% (8/24 patients) in the surgery plus adjuvant chemotherapy and surgery-only groups, respectively. Overall pooled odds ratio was 1.07 (95% confidence interval, 0.26–4.37; p = 0.92). In secondary localized malignant GCTB, the mortality rates were 30.6% (11/36 patients) and 62.2% (23/37 patients) in the surgery plus adjuvant chemotherapy and surgery-only groups, respectively. The overall pooled odds ratio was 0.31 (95% confidence interval, 0.10–0.95; p = 0.04). The effect of adjuvant chemotherapy remains unclear for primary localized malignant GCTB, but adjuvant chemotherapy improved the survival of patients with secondary localized malignant GCTB.