Multifocal Osteosarcoma: Unusual Presentation and Imaging Findings

Comprehensive conservative treatment for multiple metastases of skull osteosarcoma: A case report

Background

Skull osteosarcoma is relatively rare, and it is difficult to be diagnosed according to medical history and imaging examination due to the complex structure and diverse components of the brain. Consequently, there is only a limited number of patients who can undergo neoadjuvant chemotherapy before the operation. Although neoadjuvant chemotherapy plays an important role in the treatment of osteosarcoma, there is still a "bottleneck" in the current treatment method which when pulmonary metastasis occurs, or surgical treatment is not Enneking appropriate. Under such circumstances, the choice of treatment can be an issue.

Case

A 16-year-old male patient with multiple metastases of skull osteosarcoma was reported. The patient suffered not only tinnitus and hearing loss in the right ear but also right facial paralysis and headache. The preoperative brain MRI showed a tumor in the right cerebellopontine angle (CPA) area. He underwent skull tumor resection at another hospital in November 2018, during which process the biopsy revealed epithelioid osteoblastoma-like osteosarcoma. The patient had supplemental radiotherapy 1 month after surgery because of tumor recurrence. 32 months afterward, pulmonary metastases and multiple bone metastases were found. Then the patient underwent multiple conservative treatments which include Denosumab, Anlotinib, and DIA (cisplatin + ifosfamide + doxorubicin) chemotherapy at our hospital. After a series of 6 cycles of treatment, the patient can walk without aid. Lactate dehydrogenase (LDH) and Alkaline phosphatase (AKP) returned to a normal level. Fluorodeoxyglucose (FDG) metabolism in all bone metastases decreased to normal except for the ones in the proximal left femur, and the FDG metabolism in the left femur is significantly lower than that before treatment. Multiple bone metastases showed different extents of high-density calcification, and the volume of the local bone metastases has been reduced significantly. The patient's condition stayed stable at latest follow-up.

Conclusion

We found that multiple conservative treatments, which include Denosumab, Anlotinib and DIA chemotherapy, can improve patients' life quality, and help avoid further osteolytic destruction for patients with skull osteosarcoma and multiple metastases. Its specific mechanism and scope of the application still need to be further studied.

Pediatric Osteosarcoma: Pearls and Pitfalls

Osteosarcoma is a malignant bone tumor most commonly presenting in children. It has a bimodal distribution with a peak incidence occurring during the ages of 10-14 years old and in adults greater than age 65. The first peak of osteosarcoma correlates with the increased proliferation of bone during the pubertal growth period. Osteosarcoma most frequently presents with localized bone pain, swelling, and an antalgic gait. The patient may attribute symptoms to trauma or strenuous exercise, causing the patient to be managed conservatively. In these cases, the pain persists and eventually leads to further evaluation. The most common type of osteosarcoma is the conventional high-grade osteosarcoma. For conventional osteosarcoma, the diagnosis is typically made or strongly suggested based upon the initial radiographic appearance. Other types of osteosarcomas include low grade central, telangiectatic, small-cell, surface and intracortical. Consequently, it is important for radiologists to be aware of these subtypes and the imaging features that differentiate them from other etiologies to prevent a delay in treatment.

Low-field magnetic resonance imaging characteristics of multifocal vertebral lesions in dogs

BACKGROUND

There is a lack of information regarding magnetic resonance imaging (MRI) features of polyostotic vertebral lesions in dogs. The aim of this retrospective study was to identify and differenciate low-field MRI features of aggressive versus benign multifocal vertebral diseases in dogs.

METHODS

MRI examinations from 49 dogs with polyostotic vertebral lesions were reviewed. Images were evaluated for vertebral intensity changes, expansile lesions, new bone formation, cortical bone interruption, paravertebral musculature changes, lymphadenomegaly, spinal cord compression and spinal cord signal changes.

RESULTS

Twenty-nine dogs with non-aggressive bone lesions and 20 dogs with aggressive vertebral lesions were included. Non-aggressive lesions had variable T2-weighted fast spin-echo (T2W) signal intensity and the majority displayed low signal intensity on short tau inversion recovery (STIR). Aggressive lesions predominantly had high T2W and STIR signal intensity, with variable signal intensity on T1-weighted spin-echo and contrast enhancement. Aggressive lesions were associated with spinal pain (p < 0.01), new bone formation (p = 0.02), spinal cord compression (p < 0.01) and lymphadenomegaly (p < 0.01). Cortical interruption (p < 0.01) and paravertebral musculature changes (p < 0.01) were the strongest indicative imaging features for aggressive lesions.

CONCLUSION

Spinal pain, spinal cord compression, new bone formation, lymphadenomegaly and especially cortical interruption and paravertebral musculature signal intensity changes were the best discriminators for differentiating malignant from benign vertebral lesions.

Advance MR evaluation of synchronous multifocal osteosarcoma with pathologic fracture

Objective:

Synchronous multifocal osteosarcoma is a rare condition in which the osteosarcoma presents with multiple bone lesions at the time of diagnosis, usually without any visceral metastases. The first case was described in early 1930s by Silverman. To report a case of synchronous multifocal osteosarcoma in adolescent with pathologic fracture.

Methods:

An 18-year-old girl presented with a painful mass in the right thigh of 4 months’ duration and a history of thigh bone fracture a month ago. Patient’s medical records and family history was unremarkable. Physical examination showed angulation and shortening at right femoral region with tenderness and swelling. Initial radiograph and magnetic resonance (MR) images showed multiple lesions in right femoral shaft and pelvic bone with primary tumor in right distal femur with pathologic fracture and multiple bone marrow lesions found in the contralateral bones. Imaging and histopathological results supported the diagnosis of synchronous multifocal osteosarcoma. After following the chemotherapy as the treatment of choice, the radiograph and MRI evaluation were done and showed reduction of the mass size with union of the destructed part with the formation of callus. The advance MRI revealed reduction of the overall mass and the composition of the viable area compared to previous study. The patient had satisfying response to chemotherapy series and a better functional outcome on subsequent visits.

Results:

Diagnosis of synchronous multifocal osteosarcoma was based on patient and family history and finding of multiple lesions in the MR images, meanwhile the plain radiograph only revealed the primary tumor. Amstutz described multifocal osteosarcoma as presence of one primary tumor and several smaller lesions. Most recent reviews concluded that multifocal osteosarcoma is bone-to-bone metastatic process rather than multicentric origin. The limitation in this case was absence of thoracic CT which is suggested to rule out any pulmonary metastases instead of routine chest radiograph.

Conclusion:

Although satisfying improvement was clinically achieved, further advanced MRI would be indicated to evaluate the progression of tumor and its respond to therapy.

Diffuse Increased 68Ga-DOTATATE But Unimpressive 18F-FDG Osseous Activity in a Patient With Rapid-Progressing Synchronous Multifocal Osteosarcoma

Osteosarcoma is usually F-FDG-avid. Here we report a case of an 18-year-old young man with widespread osteoblastic and slight osteolytic changes, which had diffusely increased Ga-DOTATATE uptake in the osseous lesions, whereas the F-FDG PET/CT was unrevealing. The final diagnosis is synchronous multifocal osteosarcoma based on the pathological, clinical, and imaging features.

Triple primary malignancies of surface osteosarcoma of jaw, myelodysplastic syndrome and colorectal cancer as a second primary cancer detected by PET2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography: A case report

Second primary malignancy (SPM) is a severe issue for cancer survivors, particularly for osteosarcoma (OS) survivors. To date, the associations between subsequent SPM and OS have been well reported. Hematogenic and solid malignancies tend to occur following OS treatment. Reportedly, 2-[¹⁸F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is mainly used in OS patients for initial cancer staging, to evaluate the response of neoadjuvant chemotherapy, and when recurrence or metastasis is clinically suspected. The present case report describes a 70-year-old man diagnosed with three primary malignancies: jaw OS, myelodysplastic syndrome and colorectal adenocarcinoma. To the best of our knowledge, this combination of malignancies has not been reported previously. Until now, there is no specific protocol of postoperative FDG-PET for OS patients. Few studies have described OS follow-up methods; therefore, there is no consensus on proper follow-up methods. In the present case report, the colorectal early-stage SPM was observed, without any symptoms, by FDG-PET/computed tomography. To avoid overlooking solid SPMs, it is suggested that FDG-PET should be performed in the long-term follow-up of OS patients.