Functional and radiographic evaluation of 214 aggressive benign bone lesions treated with curettage, cauterization, and cementation: 24 years of follow-up

Application of Machine Learning for Differentiating Bone Malignancy on Imaging: A Systematic Review

An accurate diagnosis of bone tumours on imaging is crucial for appropriate and successful treatment. The advent of Artificial intelligence (AI) and machine learning methods to characterize and assess bone tumours on various imaging modalities may assist in the diagnostic workflow. The purpose of this review article is to summarise the most recent evidence for AI techniques using imaging for differentiating benign from malignant lesions, the characterization of various malignant bone lesions, and their potential clinical application. A systematic search through electronic databases (PubMed, MEDLINE, Web of Science, and clinicaltrials.gov) was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 34 articles were retrieved from the databases and the key findings were compiled and summarised. A total of 34 articles reported the use of AI techniques to distinguish between benign vs. malignant bone lesions, of which 12 (35.3%) focused on radiographs, 12 (35.3%) on MRI, 5 (14.7%) on CT and 5 (14.7%) on PET/CT. The overall reported accuracy, sensitivity, and specificity of AI in distinguishing between benign vs. malignant bone lesions ranges from 0.44–0.99, 0.63–1.00, and 0.73–0.96, respectively, with AUCs of 0.73–0.96. In conclusion, the use of AI to discriminate bone lesions on imaging has achieved a relatively good performance in various imaging modalities, with high sensitivity, specificity, and accuracy for distinguishing between benign vs. malignant lesions in several cohort studies. However, further research is necessary to test the clinical performance of these algorithms before they can be facilitated and integrated into routine clinical practice.

Treatment alternatives and clinical outcomes of bone filling after benign tumour curettage. A systematic review

BACKGROUND

Benign and pseudo-neoplastic bone lesions are usually treated by curettage and filling of the cavity. This filling is usually achieved with the use of autologous bone grafts, bone cement, allografts, xenografts, or synthetic bone substitutes. Recently, some authors have suggested that these defects do not require filling for consolidation but the respective rate of complications of each method is not well defined. Therefore, we did a systematic review aiming to answer: (1) Not filling bone cavities after benign bone tumour curettage may increase the rate of fractures? (2) Can the volume of the bone defect in itself be a specific or reliable predictor of fracture? (3) Does the mean functional outcome, recurrence, non-weight bearing time, other postoperative complications or bone consolidation time vary between the methods of filling?

PATIENTS AND METHODS

The PubMed (2407 articles) and Latin American and Caribbean Health Sciences Literature (LILACS) (50 articles) databases were reviewed, without restriction considering publication date. After exclusion criteria, 62 articles were selected for data collection. Filling or not filling (UN), methods of filling, fracture rate, bone defect size, mean functional outcome, recurrence, non-weight bearing time, other postoperative complications, consolidation time were the data of interest.

RESULTS

The number of patients was 2555 distributed among the different filling methods. Unfilled cavities were associated with higher fracture rate [20/302 (6.62%)] versus 4/189 (2.12%) for allografts, 14/343 (4.08%) for cement filling, 4/247 for autograft (1.62%), and 12/580 (2.07%) for bone substitute. The volume of the bone defect alone is not a specific or reliable predictor of fracture. All filling methods were similar regarding the mean functional outcome, recurrence rate and consolidation time. The bone cement allowed early weight bearing time (mean of weeks): UN: 9.67; autologous bone grafts: 9.8; bone cement: 0.5; allografts: 9.0; synthetic bone substitutes: 9.96.

CONCLUSION

Not filling the bone cavity after benign bone tumour curettage is an alternative, but can increase fracture rate, even in small volume bone defects. The use of prophylactic fixation drastically reduces the fracture rate. Filling with cement reduces weight bearing time. There are little differences between the methods used to fill, even compared to not filling the cavity.

LEVEL OF EVIDENCE

III; systematic review.

Giant cell tumor of the femoral neck: case report

The authors present the case of a patient with a giant cell tumor of the left femoral neck, with adjacent progressive invasion of bone tissue. Initial treatment was done with local curettage and autologous bone graft from fibula, electrocauterization and filling with methyl methacrylate. A local tumoral relapse was present after one year; therefore a new surgical procedure was necessary, with proximal femoral wide resection and unconventional endoprosthesis fixation. The article discusses the clinical aspects and surgical treatment. This report aimed to demonstrate the necessity to perform wide resection for giant cell tumor of the femoral neck, prioritizing total resection of the tumor and its local extension, preserving limb integrity and demonstrating the complete failure of preserving surgery in cases of femoral neck involvement.

External fixation reconstruction of the residual problems of benign bone tumours

The mechanical features of and biologic response to using distraction osteogenesis with the circular external fixator are the unique aspects of Ilizarov’s contribution that allows deformity correction and reconstruction of bone defects. We present a retrospective study of 20 patients who suffered from a variety of benign tumours for which external fixators (EF) were used to treat deformity, bone loss, and limb-length discrepancy. A total of 26 bony segments in twenty patients (10 males, 10 females; mean age 17 years; range 7–58 years) were treated with EF for residual problems from the tumour itself (primary treatment) in 8 patients and for complications related to the primary surgery (secondary treatment) in 12 patients. Histological diagnoses were Ollier’s disease (n = 4), Fibrous Dysplasia (n = 5), Congenital multiple exostosis (n = 5), giant cell tumour (n = 2) and one case for chondromyxoid fibroma, desmoid fibroma, chondroma and unicameral bone cyst. Various types of external fixators used to treat these problems. These were Ilizarov, unilateral fixator, multiaxial correction frame (Biomet, Parsippany, NJ), Taylor spatial frame (Memphis, TN) and smart correction multiaxial frame. The mean follow-up time was 69.5 months (range 35–108 months). The mean external fixation time was 159.5 days (range 27–300 days). The mean external fixation index was 67.4 days/cm (12–610) in 26 limbs who underwent distraction osteogenesis. The mean length of distraction was 4.9 cm (range 0.2–14 cm). At final follow-up, all patients had returned to normal activities. Complications were in the form of knee arthrodesis in one patient, pin tract infection in six and residual shortening in eight patients. The use of EF and the principles of distraction osteogenesis, in the management of problems associated with benign bone tumours and related surgery yields successful results especially in young patients. With this approach, the risk for recurrence of shortening and deformity may be minimized with overcorrection or over-lengthening as dictated by preoperative planning.

GCT: What happened after 10 years of curettage and cement? Retrospective study of 46 cases

OBJECTIVE:

To compare the functional outcome of patients with and without arthrosis, and to determine whether the development of arthrosis is related to the distance of the tumor from the subchondral bone.

METHODS:

Forty six patients treated for Giant-cell tumor (GCT) between 1975 and 1999 met inclusion criteria. GCT was diagnosed by percutaneous biopsy and confirmed after resection, in all cases. Campanacci's and Kellgren's classification, the distance of the cement to the articular surface and MSTS score were obtained throughout the sample.

RESULTS:

The distance of the cement to the subchondral bone was associated with greater risk of developing arthrosis, but there was no difference in MSTS scores between patients with or without arthrosis.

CONCLUSION:

We found that the distance from the cement to the subchondral bone has a prognostic value regarding future arthrosis, but it does not impact on the functional outcome. Level of Evidence IV, Therapeutic Study

Accuracy and limitations of computer-guided curettage of benign bone tumors

Adequate curettage of benign bone tumors located close to articular joints or neurovascular tissue is difficult without damaging those tissues. The purpose of this study was to evaluate the adequacy of tumor removal in computer-assisted curettage of benign bone tumors. The study is a prospective case series involving eight patients with benign bone tumors located near an articular joint or major neurovascular tissue. Image-to-patient registration with the navigation system was performed using paired-points methods in conjunction with CT images. A cortical window was created to visualize the tumor cavity. After removal of the gross tumor with sharp curettes, a specially designed burr attached to a navigation probe was used to monitor the location of the burr tip in real time. The high-speed burr extended the bony margin a few millimeters over the cavity wall. The empty cavity was then filled with bone cement. We assessed the accuracy of curettage and articular involvement by comparing pre- and post-operative CT images. In all cases, deeply seated or multi-cystic tumors were sufficiently removed according to the pre- and post-operative fusion CT images. The subchondral bone was punctured when the initial thickness of the subchondral bone was less than 2.5 mm. However, use of the computer-guided burr was safe if the thickness of the subchondral bone was greater than 3 mm. Computer-assisted curettage is a safe and useful method for localizing deeply seated benign bone tumors. However, use of the burr should be avoided when the bone thickness is less than 3 mm to avoid major tissue damage.

A eletrocauterização isolada como adjuvante no tratamento dos tumores ósseos benignos

OBJETIVOS: Avaliar o papel da eletrocauterização como método adjuvante isolado na ressecção intralesional dos tumores ósseos benignos, levando em conta fatores associados à recorrência dessas lesões. MÉTODOS: Foram incluídos 47 pacientes com diagnóstico de tumores ósseos benignos que foram tratados com curetagem associada a eletrocauterização como método adjuvante. Os pacientes foram acompanhados por um tempo médio de 32,7± 19,4 meses e foi avaliada a taxa de recidiva em relação às seguintes variáveis: idade, sexo, localização do tumor, tipo histológico, estadiamento (B1, B2, B3), tamanho, tipo de material utilizado como preenchimento (PMMA ou enxerto ósseo). A taxa e o tipo de complicação pós-operatória também foram analisadas. RESULTADOS: A recidiva global foi de 19,1%, havendo correlação significante do grau do tumor em relação ao tempo de recidiva (p=0,028). Não foram observados outros fatores diretamente relacionados à recidiva local. CONCLUSÃO: A eletrocauterização mostrou-se um método simples, barato e eficaz no tratamento adjuvante dos tumores ósseos benignos. Nivel de Evidência IV, serie de casos.

Treatment of benign bone tumours using external fixation

We present a retrospective study of patients suffering from a variety of benign tumours in whom external fixators were used to treat deformity and limb-length discrepancy, and for the reconstruction of bone defects. A total of 43 limbs in 31 patients (12 male and 19 female) with a mean age of 14 years (2 to 54) were treated.

The diagnosis was Ollier’s disease in 12 limbs, fibrous dysplasia in 11, osteochondroma in eight, giant cell tumour in five, osteofibrous dysplasia in five and non-ossifying fibroma in two. The lesions were treated in the tibia in 19 limbs, in the femur in 16, and in the forearm in eight. The Ilizarov frame was used in 25 limbs, the Taylor Spatial Frame in seven, the Orthofix fixator in six, the Monotube in four and the Heidelberg fixator in one. The mean follow-up was 72 months (22 to 221).

The mean external fixation period was 168 days (71 to 352). The mean external fixation index was 42 days/cm (22.2 to 102.0) in the 22 patients who required limb lengthening. The mean correction angle for those with angular deformity was 23° (7° to 45°).

At final follow-up all patients had returned to normal activities. Four patients required a second operation for recurrent deformity of further limb lengthening. Local recurrence occurred in one patient, requiring further surgery.

Classical osteoblastoma, atypical osteoblastoma, and osteosarcoma: a comparative study based on clinical, histological, and biological parameters

OBJECTIVE

To investigate the biological behavior of classical and atypical osteoblastomas in comparison to osteosarcomas.

METHODS

Based on histological parameters, 30 osteoblastomas were subclassified as classical osteoblastomas (23/30) or atypical osteoblastoma (high cellularity, prominent blue osteoid, and epithelioid osteoblasts--7/30). Comparative immunohistochemical and clinical analysis was performed in 17 cases of patients with high-grade osteosarcoma. Formalin-fixed, paraffin-embedded archival tissue was immunostained for p53 and proliferation cell nuclear antigen. Tumors with positive p53 stain underwent molecular analyses for fragments of exon 10.

RESULTS

The mean proliferating cell nuclear antigen indexes for classical osteoblastoma, atypical osteoblastoma, and osteosarcoma were 33%, 61%, and 79%, respectively. The atypical subgroup showed similar results to those of the osteosarcoma group (P < 0.001). p53 protein was detected in 4 (13%) osteoblastomas (3 of these were atypical osteoblastoma), and 4 osteosarcomas (23%) also showed p53 positivity. DNA mutation performed in p53-positive cases was confirmed in exon 10 in 2 atypical osteoblastomas (2/3), 1 classical osteoblastoma (1/1), and 1 osteosarcoma (1/4). Disease recurrence was correlated with p53 expression (P = 0.009), atypical subtype (P = 0.031), spiculated blue bone on histology (P = 0.018), and proliferating-cell nuclear antigen labeling index > or =40 (P = 0.015).

CONCLUSION

These results validate atypical osteoblastoma as an entity, with p53 and proliferation cell nuclear antigen immuno-expression closer to that of osteosarcoma than of classical osteoblastoma. Proliferating cell nuclear antigen labeling index and p53 may be useful predictors of recurrence.

Synovial sarcoma of the extremities: prognostic factors for 20 nonmetastatic cases and a new histologic grading system with prognostic significance

PURPOSE

To evaluate 20 cases of nonmetastatic synovial sarcoma of the extremities regarding prognostic factors, and to propose a histologic grading system with prognostic significance.

METHODS

The cases of 20 patients (14 females and 6 males) with nonmetastatic synovial sarcomas of the extremities treated between 1985 and 1998, were retrospectively evaluated regarding prognostic factors. A histologic grading system with prognostic significance is proposed.

RESULTS

The mean follow-up period was 48.4 months (range, 16-116 months). There was local recurrence in 3 cases (15%), microscopic surgical margin being the only prognostic factor identified. Seven patients (35%) died of the disease in a mean postoperative period of 31.7 months (range, 16-53 months), all with pulmonary or brain metastasis. The survival rate was 65% in 48.4 months of follow-up.

CONCLUSION

The unfavorable prognostic factors identified regarding survival were high histologic grade, tumors proximal to the knee or elbow, and spontaneous tumor necrosis over 25%. Local recurrence did not have influence on survival in this study. The presence of mast cells appears to have a positive influence on survival, although statistical significance was not reached (P = 0.07). The oncologic and functional result was good in 6 cases (30%), regular in 7 (35%), and poor in 7 cases (35%).

Comparative analysis between osteosarcoma and Ewing's sarcoma: evaluation of the time from onset of signs and symptoms until diagnosis

OBJECTIVE

The purposes of this study were to describe the early signs and symptoms of osteosarcoma and Ewing's sarcoma, identify symptoms that could be used to help differentiate the two types of tumors, and determine the time elapsed between the onset of signs and symptoms and the definitive diagnosis in our service, providing information and imputus for earlier diagnosis of these tumors.

METHODS

A retrospective analysis of the medical dossiers of 365 patients under 30 years of age diagnosed with osteosarcoma or Ewing's sarcoma was performed, and the aspects of the clinical diagnosis were statistically analyzed and compared.

RESULTS

The time between the onset of signs and the symptoms was 5.25 months for osteosarcoma and 8.1 months for Ewing's sarcoma, and the most frequent (89.5%) early symptom of osteosarcoma and Ewing's sarcoma was local pain. Symptoms that might aid diagnosis included early local volume increase and the presence of fever.

CONCLUSION

The time until diagnosis of both neoplasias was higher than that reported for North America and Europe. Education of the lay public and medical professionals regarding suspicious early signs and symptoms might shorten the delay of diagnosis.

Oncologic progression of bone plasmacytomas to multiple myeloma

PURPOSE

To evaluate the clinical aspects, diagnoses, prognostic factors, and percent progression of plasmacytoma to multiple myeloma.

MATERIALS AND METHODS

103 medical records of patients suspected of plasmacytoma were surveyed covering the period between 1950 and 1998, and 30 were selected for analysis. Patients were classified into 2 groups: patients who did (n = 17) and did not (n = 13) progress to multiple myeloma. Comparative statistics regarding a variety of clinical aspects were developed.

RESULTS

Patients who progressed to multiple myeloma were younger than those who did not (52.3 +/- 2.6 vs 62.6 +/- 3.4 years; mean +/- SEM; P = 0.02). There were no significant differences in gender between groups. A higher incidence of multiple recurrence was observed in patients who progressed to multiple myeloma (75%, P = 0.049). Both groups showed a prevalence of vertebral column injuries. No significant differences were found between groups regarding the disease period (from the onset of symptoms until diagnosis) (P = 0.20) and survival (P = 0.34). The average time to progression from plasmacytoma to myeloma was 41 +/- 39 months (mean +/- SD), and the progression rate was 57%.

CONCLUSION

Patients who progressed to multiple myeloma were younger than those who did not. No significant differences were found between groups regarding sex, time from symptom onset to diagnosis, and survival time. In both groups, the most affected anatomic location was the vertebral column, and most affected sex was male. The average time to progression to multiple myeloma was 41 months. It was not possible to determine the factors that influenced the survival of patients with plasmacytoma or for those who progressed to multiple myeloma.