Characteristics of Benign and Malignant Bone Tumors Registered in the Hiroshima Tumor Tissue Registry, 1973-2012

Artificial intelligence and machine learning applications for the imaging of bone and soft tissue tumors

Recent advancements in artificial intelligence (AI) and machine learning offer numerous opportunities in musculoskeletal radiology to potentially bolster diagnostic accuracy, workflow efficiency, and predictive modeling. AI tools have the capability to assist radiologists in many tasks ranging from image segmentation, lesion detection, and more. In bone and soft tissue tumor imaging, radiomics and deep learning show promise for malignancy stratification, grading, prognostication, and treatment planning. However, challenges such as standardization, data integration, and ethical concerns regarding patient data need to be addressed ahead of clinical translation. In the realm of musculoskeletal oncology, AI also faces obstacles in robust algorithm development due to limited disease incidence. While many initiatives aim to develop multitasking AI systems, multidisciplinary collaboration is crucial for successful AI integration into clinical practice. Robust approaches addressing challenges and embodying ethical practices are warranted to fully realize AI's potential for enhancing diagnostic accuracy and advancing patient care.

Vertebral Primary Bone Lesions: Review of Management Options

The assessment and treatment of vertebral primary bone lesions continue to pose a unique yet significant challenge. Indeed, there exists little in the literature in the way of compiling and overviewing the various types of vertebral lesions, which can often have complicated intervention strategies. Given the severe consequences of mismanaged vertebral bone tumors-including the extreme loss of motor function-it is clear that such an overview of spinal lesion care is needed. Thus, in the following paper, we aim to address the assessment of various vertebral primary bone lesions, outlining the relevant nonsurgical and surgical interventional methods. We describe examples of primary benign and malignant tumors, comparing and contrasting their differences. We also highlight emerging treatments and approaches for these tumors, like cryoablation and stereotactic body radiation therapy. Ultimately, we aim to emphasize the need for further guidelines in regard to correlating lesion type with proper therapy, underscoring the innate diversity of vertebral primary bone lesions in the literature.

Clinical Outcome of Patients with Pelvic and Retroperitoneal Bone and Soft Tissue Sarcoma: A Retrospective Multicenter Study in Japan

Simple Summary

We aimed to clarify the clinical outcomes of patients with pelvic and retroperitoneal bone and soft tissue sarcoma. The 3-year overall survival (OS), local control (LC) rate, and progression-free survival (PFS) were 71.7%, 79.1%, and 48.6%, respectively. The most influential poor prognostic factor for OS was distant metastasis, and for PFS, this was higher age (≥60 years). Larger primary tumor size (≥10 cm) was the only poor prognostic factor for LC. In the histological analysis, osteosarcoma showed significantly worse OS and PFS than other sarcomas in the pelvis and retroperitoneum.

Abstract

This study aimed to retrospectively analyze the clinical outcomes of patients with pelvic and retroperitoneal bone and soft tissue sarcoma (BSTS). Overall, 187 patients with BSTS in the pelvis and retroperitoneal region treated at 19 specialized sarcoma centers in Japan were included. The prognostic factors related to overall survival (OS), local control (LC), and progression-free survival (PFS) were evaluated. The 3-year OS and LC rates in the 187 patients were 71.7% and 79.1%, respectively. The 3-year PFS in 166 patients without any distant metastases at the time of primary tumor diagnosis was 48.6%. Osteosarcoma showed significantly worse OS and PFS than other sarcomas of the pelvis and retroperitoneum. In the univariate analyses, larger primary tumor size, soft tissue tumor, distant metastasis at the time of primary tumor diagnosis, P2 location, chemotherapy, and osteosarcoma were poor prognostic factors correlated with OS. Larger primary tumor size, higher age, soft tissue tumor, chemotherapy, and osteosarcoma were poor prognostic factors correlated with PFS in patients without any metastasis at the initial presentation. Larger primary tumor size was the only poor prognostic factor correlation with LC. This study has clarified the epidemiology and prognosis of patients with pelvic and retroperitoneal BSTS in Japan.

Fifth lumbar vertebrae solitary osteochondroma arising from the neural arch, a case report

Background

Osteochondromas are a benign outgrowth of bone and cartilage and one of the most common bone tumors that usually occur in long bones, with only 1–4% being located in the spine, more frequently in the cervical and upper dorsal region, and rarely the lumbar spine. Here, we report a case of lumbar spine (L5) osteochondroma arising from the neural arch.

Case presentation

A 30-year-old man presenting with a solid painless mass at the lower lumbar region. No neurological symptoms. Radiological examinations revealed an exophytic lesion in the fifth lumbar articular process, and the spinous process appears to be a solitary osteochondroma. Lumbar spine magnetic resonance imaging showed a bony lesion covered by a 2-mm-thick cartilaginous cap. Surgical en bloc resection of the mass was performed, and the histopathological examination confirmed the diagnosis of osteochondroma. No evidence of recurrence at the end of 4-year follow-up.

Conclusion

Osteochondromas are benign tumors rarely present in the spine; diagnosis can be made by the typical appearance of the cartilaginous cap over the mass in the magnetic resonance imaging. Surgical excision is the best management option.

Interventional Techniques for Bone and Musculoskeletal Soft Tissue Tumors: Current Practices and Future Directions - Part I. Ablation

Musculoskeletal (MSK) image-guided oncologic intervention is an established field within radiology. Numerous studies have described its clinical benefits, safety, cost effectiveness, patient satisfaction, and improved quality of life, thereby establishing image-guided oncologic intervention as a preferred pathway in treating patients presenting with specific benign MSK tumors. But there is a paradigm shift on the horizon because these techniques may also support established pillars (surgery, systemic treatment, radiotherapy) in the treatment of malignant MSK tumors. Unlike benign tumors, where they are used as primary therapy lines with curative intent, such interventions can be selected for malignant tumors as adjuvant treatment in painful or unstable bone or soft tissue lesions or as more palliative therapy strategies. Using examples from our clinical practices, we elaborate on the benefits of applying a multidisciplinary approach (traditionally involving MSK radiologists, oncologists, orthopaedic surgeons, microbiologists, pathologists, physiotherapists, and pain management experts), ideally within a sarcoma treatment center to deliver a patient-specific therapy plan and illustrate methods to assess the benefits of this model of care.In this article, we review the current repertoire of ablation techniques, demonstrate why such procedures offer value-based alternatives to conventional treatments of specific tumors, and reflect on future directions. Additionally, we review the advantages and limitations of each technique and offer guidance to improve outcomes.

Post-operative fracture risk assessment following tumor curettage in the distal femur: a hybrid in vitro and in silico biomechanical approach

The distal femur is the predominant site for benign bone tumours and a common site for fracture following tumour removal or cementation. However, the lack of conclusive assessment criterion for post-operative fracture risk and appropriate devices for cement augmentation are serious concerns. Hence, a validated biomechanical tool was developed to assess bone strength, depending on the size and location of artificially created tumorous defects in the distal femora. The mechanics of the bone–cement interface was investigated to determine the main causes of reconstruction failure. Based on quantitative-CT images, non-linear and heterogeneous finite element (FE) models of human cadaveric distal femora with simulated tumourous defects were created and validated using in vitro mechanical tests from 14 cadaveric samples. Statistical analyses demonstrated a strong linear relationship (R² = 0.95, slope = 1.12) with no significant difference between bone strengths predicted by in silico analyses and in vitro tests (P = 0.174). FE analyses showed little reduction in bone strength until the defect was 35% or more of epiphyseal volume, and reduction in bone strength was less pronounced for laterally located defects than medial side defects. Moreover, the proximal end of the cortical window and the most interior wall of the bone–cement interface were the most vulnerable sites for reconstruction failure.

Analyses of cancer incidence and other morbidities in gamma irradiated B6CF1 mice

With increasing medical radiation exposures, it is important to understand how different modes of delivery of ionizing radiation as well as total doses of exposure impact health outcomes. Our lab studied the risks associated with ionizing radiation by analyzing the Northwestern University Radiation Archive for animals (NURA). NURA contains detailed data from a series of 10 individual neutron and gamma irradiation experiments conducted on over 50,000 mice. Rigorous statistical testing on control mice from all Janus experiments enabled us to select studies that could be compared to one another and uncover unexpected differences among the controls as well as experimental animals. For controls, mice sham irradiated with 300 fractions died significantly earlier than those with fewer sham fractions and were excluded from the pooled dataset. Using the integrated dataset of gamma irradiated and control mice, we found that fractionation significantly decreased the death hazard for animals dying of lymphomas, tumors, non-tumors, and unknown causes. Gender differences in frequencies of causes of death were identified irrespective of irradiation and dose fractionation, with female mice being at a greater risk for all causes of death, except for lung tumors. Irradiated and control male mice were at a significantly greater risk for lung tumors, the opposite from observations noted in humans. Additionally, we discovered that lymphoma deaths can occur quickly after exposures to high doses of gamma rays. This study systematically cross-compared outcomes of different modes of fractionation evaluated across different Janus experiments and across a wide span of total doses. It demonstrates that protraction modulated survival and disease status differently based on the total dose, cause of death, and sex of an animal. This novel method for analyzing the Janus datasets will lead to insightful new mechanistic hypotheses and research in the fields of radiation biology and protection.

Musculoskeletal Tumors

Pediatric musculoskeletal tumors can arise in both bone and soft tissues. The overwhelming majority of these are benign; however, rarely, malignant neoplasms do occur. These are collectively termed sarcomas, indicating their mesenchymal origin. Sarcoma management requires careful adherence to the well-described tenets of tumor management. This article summarizes the basic principles and recent advances in the management of soft tissue and bone tumors.

Intracanalicular Osteochondroma in the Lumbar Spine

Osteochondroma is a common benign bone tumor that is relatively rare in the spine. Here, we report two cases of symptomatic solitary osteochondroma of the lumbar spine. The first case was a 61-year-old man who presented with a 2-year history of right leg numbness. Imaging findings showed that the cause of the radiculopathy was osteochondroma of the right inferior articular process at L4. The tumor was removed en bloc, and the numbness resolved. The second case was a 62-year-old man with osteochondroma of the right superior articular process at L5 that caused pain and numbness in the right leg. En bloc resection of the osteochondroma with the ligamentum flavum relieved the symptoms. Spinal osteochondroma occurs relatively frequently in elderly individuals compared with peripheral lesions and mimics a degenerative spinal disorder. Careful physical examination and imaging evaluation can reveal this tumor and surgery is effective for relieving the symptoms.

Histological, epidemiological and anatomical analysis of 193 bone tumours of the scapula

Backround

This study aimed to determine the frequency and distribution of bone tumours of the scapula as well as the histological and anatomical characteristics of these rare lesions in a large case series.

Methods

The records of all lesions of the scapula collected from 1975 to 2018 in our bone tumour registry and institute of pathology were evaluated. During these 43 years, 223 cases were identified. Analysis included assessment of age, gender, side, imaging findings, tumour location, and histological evaluation with the assignment of each lesion to one of the bone tumours according to the World Health Organization (WHO) classification of bone tumours.

Results

Bone tumours of the scapula were found in 193 cases. Mean patient age was 38.4 years (2.6–82.4). Most of the lesions were of cartilage origin (47%). 59 bone tumours were benign (30.6%), 29 were intermediate (15.0%), and 105 were malignant (54.4%). The most commonly found bone tumour was Osteochondroma (23.3%), followed by Chondrosarcoma (17.6%), Bone metastases (16.6%), Ewing sarcoma (8.8%), and Osteosarcoma (7.8%). The percentage of malignant bone tumours increased with increasing age. In patients >50 years of age, 91% had a malignant lesion of the scapula.

Conclusions

Evaluation of 193 bone tumours of the scapula revealed a high incidence of malignancy in this series, while increased patient age was identified as a potential risk factor for the development of a malignant lesion of the scapula. These findings highlight the importance of early diagnosis and treatment of suspicious lesions of the scapula to improve patient outcome.

Characteristics of 5015 Salivary Gland Neoplasms Registered in the Hiroshima Tumor Tissue Registry over a Period of 39 Years

Salivary gland neoplasms are uncommon, and their epidemiology in Japan has not been well described. We conducted a retrospective review of salivary gland tumors registered in the Hiroshima Tumor Tissue Registry over a period of 39 years. The subjects were 5015 cases ranging in age from 6 to 97 (mean, 54.3) years old. The incidence of both benign tumors and malignant tumors increased with age until 60-69 years and then declined. Among the 5015 salivary gland neoplasms, 3998 (80%) were benign and 1017 (20%) were malignant. Pleomorphic adenoma (PA) was the most frequent benign tumor (68%), followed by Warthin tumor (26%). Adenoid cystic carcinoma (ACC) (27%) and mucoepidermoid carcinoma (MEC) (26%) were the two most frequent malignant tumors. Characteristically, there was a very low incidence of polymorphous adenocarcinoma in Japan. The average annual age-adjusted incidence rate per 100,000 population was 3.3 for benign tumors and 0.8 for malignant tumors. This is the large-scale multi-institutional analysis to describe the characteristics of salivary gland neoplasms, based on the pathological tissue registry data. We hope that the present data can contribute to early diagnosis and effective treatment of salivary gland tumors and to cancer prevention.

Bone tumours of the clavicle: Histopathological, anatomical and epidemiological analysis of 113 cases

Backround

This retrospective study aimed to determine the frequency of bone tumours of the clavicle and their histopathological, anatomical and epidemiological characteristics in a large case series.

Methods

The records of 327 lesions of the clavicle collected from 1976 to 2018 in our bone tumour registry and institute of pathology were reviewed. Following data were evaluated: age, gender, side, radiological assessment, tumour location within the clavicle, and histopathological findings.

Results

Bone tumours were detected in 113 patients with a mean age of 40 years. The lateral third of the clavicle was most frequently involved. Analysis revealed 22 benign, 31 intermediate, and 60 malignant tumours. Eosinophilic granuloma was the most commonly found neoplasm (18.6%), followed by bone metastases (15.0%), Plasma cell myeloma (8.8%), Ewing sarcoma (8.8%), and Osteosarcoma (8.0%). 53% of the tumours were malignant. Mean age was 51 years in the malignant tumour group and 28 years in patients with a benign/intermediate lesion (p < 0.001).

Conclusions

The high incidence of malignant bone tumours of the clavicle found in this study highlight the importance of biopsy to prevent delay in diagnosis and treatment of these lesions, especially in patients with increased age. We believe that the results of this study are of clinical importance and may aid the physician in the management of these rare lesions.