Imaging algorithm and multimodality evaluation of spinal osteoblastoma

Sacral Osteoblastoma in a Young Male Presenting as Radicular Pain: A Rare Case Report

Introduction

Osteoblastoma is an uncommon benign bone tumor characterized by the formation of osteoid tissue, occurring more frequently in men than in women. It is often associated with osteoid osteoma and can be found at various locations in the skeleton, although it is rare in the sacrum. Typically, these lesions involve the posterior elements of the spine, including the pedicle and the lamina. We would like to present a case of sacral osteoblastoma, clinically presenting as lumbar radiculopathy, which was treated at our institute.

Case Report

A 23-year-old male presented to us with left gluteal pain radiating to the left lower limb pain for 2 years. He had multiple consultations elsewhere and was being treated as a probable case of a lumbar disc lesion with left lower limb radiculopathy. X-rays appeared normal. Magnetic resonance imaging of the lumbar spine and pelvis revealed a T2 hyperintense lesion affecting the posterior elements of S3, compressing the nerve roots. Computed tomography (CT) was a better investigation modality for osteoblastoma. En bloc excision and curettage were performed, and the histopathological analysis confirmed the diagnosis of osteoblastoma. The patient had immediate relief of symptoms postoperatively with no complications. At 2-year follow-up, the patient had no evidence of recurrence on a follow-up CT scan.

Conclusion

Osteoblastomas predominantly occur in the spine, with rare instances in the sacrum. Treatment typically involves en bloc excision. Confusing clinical presentation may delay diagnosis, resulting in persistent morbidity.

The CT and MRI features of benign calvarium and skull base osteoblastoma

OBJECTIVE

We retrospectively reviewed the CT and MRI features of patients with benign osteoblastoma in the calvarium and skull base (CSBOB).

METHODS

Nine cases of pathologically confirmed benign CSBOB were analysed retrospectively. The patients had undergone CT and/or MRI. Tumour location, size, and imaging features were reviewed and recorded.

RESULTS

The patients included four males and five females with a mean age of 27.0 years (age 14-40 years). The tumours were located in the frontal bone in 3 patients, the occipital bone in 3 patients, and in the parietal bone, sphenoid bone, and skull base in 1 patient each. On CT, the tumours measured 5.1 ± 3.3 (1.8-8.4) cm. Seven tumours were shown to have caused expansile bony destruction with an eggshell appearance and varying degrees of calcification or matrix mineralization. Multiple septa were observed in 5 tumours. Intracranial growth was observed in 5 tumours. On MRI, 7 tumours showed heterogeneous hypo- to isointensity on T1WI. Heterogeneous high signal patterns with low signal rims and septa were observed in 6 tumours on T2WI, and 4 showed a fluid-fluid level. On contrast-enhanced imaging, 6 tumours showed peripheral and septal enhancement, and 2 showed the dural tail sign.

CONCLUSIONS

Benign CSBOB is a rare tumour characterized by expansile bony destruction, septa, a sclerotic rim and calcification or matrix mineralization on CT and MRI.

ADVANCES IN KNOWLEDGE

The findings from this study contribute to a better understanding of benign CSBOB and provide valuable imaging features that can aid in its diagnosis and differentiation from other tumours in the calvarium and skull base.

Beyond Anatomy: Fat-Suppressed MR and Molecular Imaging of Spinal Pain Generators

Spine pain is highly prevalent and costly, but evaluation with clinical features and anatomic imaging remain limited. Fat-suppressed MR imaging and molecular imaging (MI) may help identify inflammatory, lesional, and malignant causes. Numerous MI agents are available, each with advantages and disadvantages. Herein, FDG PET, prostate-specific membrane antigen (PSMA), bone radiotracers, and others are highlighted. No specific pain MI agents have been identified, but mechanisms of key agents are shown in video format, and the mechanism of PSMA as a theranostic agent is displayed. A multidisciplinary approach is needed to master this topic.

Primary Angiosarcoma of Lumbar Pedicle and Transverse Process Revealed by FDG PET/CT

ABSTRACT

The primary angiosarcoma of bone is rare. It typically occurs in tubular bones, pelvis, and trunk. However, its occurrence in the lumbar pedicle, and transverse process is infrequent. Thus, we present the imaging findings of FDG PET/CT in a rare case of primary angiosarcoma of lumbar pedicle and transverse process. It presented as solitary osteolytic bone destruction in the right pedicle and transverse process of L4 with intense FDG uptake. This case added knowledge of another rare occurrence site of primary angiosarcoma of bone, which should be considered as a differential diagnosis when we meet similar image appearance on FDG PET/CT.

Multimodal Imaging Evaluation and Clinical Progress of Spinal Osteoblastoma: A Comprehensive Review

Spinal osteoblastoma is rare clinically, with insidious onset, atypical symptoms, and various imaging manifestations, which can easily lead to misdiagnosis and delayed diagnosis. It can cause severe neurological dysfunction in patients with intermediate to advanced stages and may easily recur after surgery. Imaging examinations such as radiography, computed tomography, magnetic resonance imaging, and positron emission tomography have different value for the diagnosis of spinal osteoblastoma, but they lack specificity. The preferred treatment is surgical resection, which is technically difficult, and in some cases, osteoblastoma cannot be completely removed. New clinical approaches such as radiofrequency ablation, radiotherapy, targeted chemotherapy, and other comprehensive treatments have emerged and are progressing rapidly, but no unified norms have yet been developed. This manuscript provides a systematic review of the literature and provides an extensive and comprehensive review of this rare tumor in terms of multimodality imaging manifestations and clinical progress.

Osteoblastoma of the Rib Mimicking Lymphomatous Involvement on 18F-FDG PET/CT Imaging

ABSTRACT

We present a case of rib osteoblastoma in a patient with NK/T cell lymphoma. Osteoblastoma was incidentally found in a 63-year-old man in the axillary segment of the fifth rib and was misdiagnosed as lymphomatous involvement on staging 18F-FDG PET/CT. The radiological features in the CT component of PET/CT were atypical. After surgery, the diagnosis of osteoblastoma was confirmed by histopathologic findings.

Epithelioid osteoblastoma with secondary aneurysmal bone cyst and FOS gene rearrangement

Epithelioid osteoblastoma, sometimes equated with aggressive osteoblastoma, is a variant of osteoblastoma that typically demonstrates more worrisome imaging and pathological features compared to conventional osteoblastoma. These more aggressive features can overlap with those seen in osteosarcoma, creating a diagnostic challenge for radiologists and pathologists. Recent identification of FOS and FOSB gene rearrangements in osteoid osteoma and osteoblastoma has allowed for greater diagnostic confidence following biopsy, but careful radiological-pathological correlation remains a key component for guiding appropriate management. Although the imaging features of conventional osteoblastoma have been previously described, there are limited examples in the literature of the imaging appearance of epithelioid osteoblastoma, and none with secondary aneurysmal bone cyst. In this case report, we detail the clinical, imaging, and histological characteristics of a proximal femoral epithelioid osteoblastoma which was pathologically confirmed by FOS and FOSB genetic testing. The initial imaging impression favored a malignancy, but when the biopsy results were correlated in a multidisciplinary fashion with the imaging, epithelioid osteoblastoma became the leading diagnosis which was subsequently genetically confirmed. This case emphasizes the value of multidisciplinary radiology-pathology correlation in routine practice.

Benign Bone-Forming Tumors

Benign bone-forming tumors comprise osteomas, osteoid osteomas, and osteoblastomas. Osteomas affect a wide age range and are usually discovered incidentally. They occur predominantly in the craniofacial skeleton and are classically composed of compact bone. Osteoid osteomas and osteoblastomas are painful lesions occurring in young patients. They are morphologically similar and characterized by FOS gene rearrangement and c-FOS expression at a protein level. Osteoid osteomas are usually smaller than 2 cm in maximum dimension with limited growth potential; osteoblastomas are larger than 2 cm and may be locally aggressive. Histologically both are composed of anastomosing trabeculae of woven bone.