Update in Imaging Evaluation of Bone and Soft Tissue Sarcomas / Atualização na avaliação por imagens dos sarcomas ósseos e das partes moles

Abstract The evolution in imaging evaluation of musculoskeletal sarcomas contributed to a significant improvement in the prognosis and survival of patients with these neoplasms. The precise characterization of these lesions, using the most appropriate imaging modalities to each clinical condition presented, is of paramount importance in the design of the therapeutic approach to be instituted, with a direct impact on clinical outcomes. The present article seeks to update the reader regarding imaging methodologies in the context of local and systemic evaluation of bone sarcomas and soft tissues.

Resumo A evolução na avaliação por imagens dos sarcomas musculoesqueléticos contribuiu para melhora significativa no prognóstico e na sobrevida dos portadores destas neoplasias. A caracterização precisa destas lesões, mediante utilização das modalidades de imagem mais adequadas a cada condição clínica apresentada, é de suma importância no delineamento da abordagem terapêutica a ser instituída, com impacto direto sobre os desfechos clínicos. O presente artigo busca atualizar o leitor a propósito das metodologias de imagem no contexto da avaliação local e sistêmica dos sarcomas ósseos e das partes moles.

Osteoblastoma in the Distal Humerus of a Cat.

A 7-year-old neutered male domestic shorthair cat was presented with chronic lameness in the right forelimb. A cystic bony lesion was identified in the distal right humerus and amputation was performed. The epiphyseal trabecular bones of the capitulum and trochlea was replaced by a tan to pink, expansile mass that was surrounded by a thin rim of cortical bone. Microscopically, the tumour was composed of a bland, osteoid producing spindle cell population within a well-vascularized fibrous stroma. Radiographical and histological features were consistent with osteoblastoma. Osteoblastoma and the related osteoid osteoma are uncommon, benign osteoblastic tumours that are reported rarely in animals. These tumours should be considered as differential diagnoses for slow growing, cystic bony lesions in cats.

Occult phosphaturic mesenchymal tumour of femur cortex causing oncogenic osteomalacia - diagnostic challenges and clinical outcomes.

BACKGROUND: Tumor induced osteomalacia (TIO) are extremely rare paraneoplastic syndrome with less than 300 reported cases. This report highlights the pitfalls and challenges in diagnosing and localizing TIO in patients with refractory and resistant osteomalacia. PATIENT AND METHODS: 41- year gentleman with 4-year history of musculoskeletal weakness and pathologic fractures presented in wheelchair bound incapacitated state of 1-year duration. Investigations were significant for severe hypophosphatemia, severe phosphaturia, normal serum calcium, reduced 1,25-dihydroxy vitamin-D, elevated ALP, elevated intact parathyroid hormone (iPTH), and pseudo-fractures involving pelvis and bilateral femur. Whole body MRI and 99mTc methylene diphosphonate bone-scan were also normal. Whole body FDG-PET scan involving all 4 limbs revealed a small FDG avid lesion at lateral border of lower end of left femur (SUV max 3.9), which was well characterized on 3-dimensional CT reconstruction. Plasma C-terminal fibroblast growth factor (FGF)-23 was 698 RU/ mL (normal < 150 RU/ml). Wide surgical excision of the tumor was done. Histopathology confirmed mesenchymal tumor of mixed connective tissue variant. Serum phosphorous normalized post-surgery day-1. High dose oral calcium and vitamin-D was continued. FGF-23 normalized post surgery (73RU/ml). Physical strength improved significantly and now he is able to walk independently. CONCLUSION: TIO is frequently confused with normocalcemic hyperparathyroidism and vitamin-D resistant rickets/osteomalacia, which increases patient morbidity. Imaging for tumor localization should involve whole body from head to tip of digits, cause these tumors are notoriously small and frequently involve digits of hands and legs. Complete surgical removal of the localized tumor is key to good clinical outcomes.

Osteopoikilosis found incidentally in a 17-year-old adolescent with femoral shaft fracture: A case report.

RATIONALE: Osteopoikilosis is a rare and asymptomatic disease of the bone, which is often discovered occasionally on radiography for irrelevant complaints. Characterized by multiple, small, circular, or oval-shaped radiodense lesions, it may be confused with bony metastatic tumors. PATIENT CONCERNS: The present study describes a case of a 17-year-old adolescent who suffered from pain and movement limitation of his left thigh following a fall from standing height. DIAGNOSES: Plain radiographs showed spiral fracture in left femoral shaft; besides, multiple scattered sclerotic lesions of variable size were also observed over the bilateral proximal femurs, left distal femur, proximal tibia, and distal tibia and fibula through X-rays, computed tomography, and magnetic resonance imaging. The patient was finally diagnosed with left femoral shaft fracture and osteopoikilosis. INTERVENTIONS: The patient underwent reduction and internal fixation with intramedullary nail a week after injury. OUTCOMES: The patient was discharged without any complications 12 days after the surgery. At the 3-month follow-up, the patient recovered well and remained symptom-free with no changes to his sclerotic lesions. LESSONS: Although this case is not so complicated, we have to be cautious when differentiating osteopoikilosis and bony metastases in clinical practice in future, which should avoid causing undue distress to both the patients and doctors.

Benign bone tumors.

Benign bone lesions are a broad category that demonstrates a spectrum of activities from latent to aggressive. Differentiating the various tumors is important in order to properly determine necessary intervention. This chapter focuses on the presentation, imaging, diagnostic features, and treatment of the most common benign bone tumors in order to help guide diagnosis and management.

Primary osseous tumors of the spine.

Primary osseous spinal tumors are relatively rare in comparison with metastatic disease, myeloma, and lymphoma. Despite their rarity, the interpreting radiologist must be aware of the typical imaging features to provide appropriate diagnosis for guidance of clinical management. The age of occurrence, distribution longitudinally in the spine, and distribution axially within the vertebra combined with typical imaging appearances can help indicate the correct diagnosis. This article reviews the diagnostic features of benign and malignant primary bone spinal tumors.

Associations of single nucleotide polymorphisms with malignant and borderline bone tumors.

Bone neoplasms - are a rare group of diseases, which ethiology and pathogenesis are not fully understood. We have studied 6 single nucleotide polymorphisms rs792/(GHI), rs7956547(IGFI), rs3761243(GNRH2), rs11737764(FGF2), rs6599400(FGFR3), and rs1690916(MDM2) associations with bone tumors. In our work we've detected significant associations with some single nucleotide polymorphisms: IGFl.rs7956547, GNRH2.rs3761243 and FGFR3.rs6599400 in patients with malignant and borderline bone tumors.

Ossifying fibromyxoid tumour: a rare soft tissue tumour of intermediate malignancy.

Ossifying fibromyxoid tumours (OFTs) are uncommon soft tissue tumours. A 73-year-old male presented with a painless exophytic mass located in the left scapular area which was identified 1 year earlier. An incisional biopsy was performed and microscopic features were compatible with OFT. Radiologic evaluation revealed multiple pulmonary metastasis. Although many cases persue an indolent biologic behaviour, local recurrence and metastasis have been reported and long-term follow-up should be considered.

Calvarial lesions: a radiological approach to diagnosis.

Calvarial lesions are frequently identified in radiological studies. A wide variety of neoplasms and non-neoplastic lesions can involve the calvarium, and their imaging appearances vary according to their pathologic features. These lesions are usually asymptomatic but may manifest as a lump with or without associated pain. Clinical information, including the age of patient, is an important factor in the diagnostic process. In this paper, we illustrate the value of cross-sectional imaging techniques by computed tomography (CT) and magnetic resonance imaging (MRI) in evaluating these lesions. We also review the literature and discuss the specific imaging characteristics of the most common calvarial lesions in order to provide information that can guide radiological diagnosis or limit differential diagnosis.

Spinal tumors in children.

Pediatric spine tumors encompass a diverse group of pathologic diagnoses that differ markedly based on the location and age of the child. Children can be affected by primary and metastatic tumors, making the differential diagnosis and treatment options extensive. This article discusses the features of spinal tumors in children based primarily on location: extradural, intradural-extramedullary, and intramedullary tumors. Because this article deals with such a broad topic, detailed descriptions and outcomes of surgical and nonsurgical treatments for each particular tumor are limited. Rather, the key clinical, diagnostic, and therapeutic features of each tumor are discussed.

Extraosseous osteosarcoma arising from the small intestinal mesentery.

Extraskeletal osteosarcoma (EOS) is a highly aggressive and exceedingly rare mesenchymal tumor. Due to the rare nature of the disease, the diagnosis can be difficult and is often confirmed only after diagnostic laparotomy and histopathology. We describe the clinical history, radiologic and histomorphologic presentation, and clinical management of a 61-year-old patient who presented with abdominal pain. Abdominal ultrasound and computerized tomography (CT) scan revealed a calcified intra-abdominal mass. Following an explorative laparotomy, histology showed a large extraosseous osteosarcoma of the small bowel mesentery. Therapy according to the Cooperative Sarcoma Study-96 (COSS-96) was commenced. Diagnosis, management, and outcome in the context of the current literature are discussed. To our knowledge, this is the first description of an extraosseous osteosarcomas in the small bowel mesentery in the literature.

Tumors of the spine in children.

In children, tumors of the spine are much rarer than intracranial tumors. They are classified into intramedullary, intradural-extramedullary, and extradural tumors. Magnetic resonance imaging provides crucial information regarding the extent, location, and internal structure of the mass, thus critically narrowing the differential diagnosis and guiding surgery.

Cutaneous malignant ossifying fibromyxoid tumor.

A 76-year-old woman presented with a well-circumscribed 3 cm mass of her right buttock. The tumor, partially surrounded by a shell of woven and lamellar bone, had a lobular arrangement of highly cellular islands of tumor cells embedded in a variably fibrous to myxoid stroma. The lesional cells had well defined cytoplasmic membranes with varying amounts of clear to lightly eosinophilic cytoplasm. The nuclei exhibited moderate to severe nuclear atypia. Areas of tumor necrosis were present. The mitotic rate was 17 MF/50 high-power fields. The tumor was diagnosed as an ossifying fibromyxoid tumor (OFMT). OFMT is a rare tumor first described in 1989. Although OFMT usually occurs in deep soft tissue, up to 11% of reported lesions presented as cutaneous tumors. OFMT usually present in adults on the extremities or trunk. Most are histologically bland and apparently benign tumors, but OFMT with high nuclear grade, high cellularity, and >2 MF/50 high-power fields have shown potential for aggressive behavior including metastasis. OFMT with these features should be considered sarcomas. Given the histologic features, this tumor was considered a malignant OFMT. The patient had a wide excision. The patient died secondary to unrelated comorbidities without evidence of recurrence or metastasis.

Osteosarcoma (osteogenic sarcoma).

Osteosarcoma is a primary malignant tumour of the skeleton characterised by the direct formation of immature bone or osteoid tissue by the tumour cells. The classic osteosarcoma is a rare (0.2% of all malignant tumours) highly malignant tumour, with an estimated incidence of 3 cases/million population/year. Osteosarcoma arises predominantly in the long bones and rarely in the soft tissues. The age at presentation ranges from 10 to 25 years of age. Plain radiographs, computed tomography, magnetic resonance imaging, angiography and dynamic bone scintigraphy are used for diagnosis, evaluation the extent of tumour involvement and decision of the type of operation and, if necessary, the type of reconstruction. Years ago, all patients with osteosarcoma were treated by amputation but the cure rate was under 10% and almost all patients died within a year from diagnosis. Today, for localised osteosarcoma at onset (80% of cases) treated in specialized bone tumour centres with pre- and postoperative chemotherapy associated with surgery, the percentage of patients cured varies between 60% and 70%. Surgery is conservative (limb salvage) in more than 90% of patients. Prognosis is more severe (cure rate about 30%) for tumours located in the axial skeleton and in patients with metastasis at onset.

Benign primary tumours of the ribs.

Benign primary tumours of the ribs are rare and may be identified during the investigation of a clinically suspected abnormality or as an incidental finding. This review describes the spectrum of benign tumours that can involve the rib and illustrates the radiographic, computed tomography (CT) and magnetic resonance (MR) imaging appearances that may facilitate diagnosis.