A Rare Case of Intracranial Metastasis of Chondroblastic Osteosarcoma from Lungs: A Case Report and Review of Literature

Abstract

Osteosarcoma are the most common primary bone tumors in children and adolescents. Brain metastases of osteosarcoma is usually a terminal event in the disease course. Surgical resection of the brain metastatic lesion forms the mainstay of treatment with chemotherapy and radiotherapy as add-ons. We present the case of a 57-year-old woman who presented with complains of breathlessness and headache. Contrast-enhance computed tomography (CECT) showed a large left lung mass. Magnetic resonance imaging (MRI) of the brain depicted an anterior temporal space occupying lesion. The patient underwent surgical removal of the mass lesion, with biopsy revealing the diagnosis as chondroblastic osteosarcoma.

 

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Keywords

osteosarcoma - chondroblastic - metastases

Introduction

Osteosarcomas are the most common malignant primary bone tumors in children and adolescents.[1] Several variants are seen, namely, conventional, telangiectatic, small cell, multifocal, periosteal, and parosteal. The conventional variant is the predominant variant with three subtypes: osteoblastic, chondroblastic, and fibroblastic. Chondroblastic osteosarcoma represents roughly a quarter of cases with a predominant cartilage differentiation.[1] [2] Primary extraosseous osteosarcomas are uncommon lesions, and those originating within the lung are especially rare accounting for approximately 0.01% of primary lung neoplasms.[3] We hereby report a case of large left temporal intracranial metastasis in a 57-year-old woman with primary lung osteosarcoma.

 

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Case Presentation

We present a case of 57-year-old woman who presented to the pulmonary outpatient (OPD) with complaints of breathlessness, associated with dry cough for 5 months, and on and off left-sided headache for the past 4 months. The patient was a chronic smoker for 25 years. On examination, the patient had decreased movements on the left side of the chest, stony dull note on percussion over the left infraclavicular and infrascapular chest regions, and reduced air entry on auscultation over these areas. On neurological examination, the patient did not have any deficits. Chest X-ray of the patient revealed complete opacity on the left side of the lung field ([Fig. 1A]). Contrast-enhanced computed tomography (CECT) of the chest was done, which was showed a large heterogeneously enhancing lesion occupying the entire left lung with involvement of surrounding bony structures and left-sided minimal pleural effusion ([Fig. 1B]). Positron emission tomography (PET) scan was performed, which depicted a metabolically active large soft tissue mass involving the entire left hemithorax, left temporal intracranial metastasis, with pancreatic and opposite lung metastasis. No evidence of metabolically active lesions elsewhere was seen. The patient underwent transbronchial biopsy of the left lung mass and the lesion was diagnosed as chondroblastic osteosarcoma.

Fig. 1 (A) Posteroanterior view of the chest X-ray shows complete whiteout of the left lung. (B) Contrast-enhanced computed tomography (CECT) of the chest shows a hyperdense lesion occupying the entire left lung. (C) Fluid attenuated inversion recovery imaging shows an anterior temporal lobe space occupying lesion abutting the dura with extensive perilesional edema. (D) Contrast-enhanced magnetic resonance imaging of the brain shows a heterogeneously enhancing space occupying lesion with areas of necrosis. (E) CECT of the brain shows an enhancing space occupying lesion in the anterior temporal lobe with perilesional edema. (F) Noncontrast computed tomography of the head done postoperatively shows good operative cavity with absence of any hematoma.

Magnetic resonance imaging (MRI) of the brain showed a large left anterior temporal space occupying lesion measuring 3.5 cm × 3.2 cm closely abutting the dura ([Fig. 1C, D]). Preoperatively CECT of the brain was done, which showed a heterogeneously enhancing space occupying lesion in the anterior temporal lobe ([Fig. 1E]). In view of significant mass effect in imaging, decision was taken to operate the patient for intracranial space occupying lesion. Differentials kept were cerebral metastasis, meningioma, glioblastoma, Dysembryoplastic Neuroepithelial Tumor (DNET), ganglioglioma, and cerebral abscess.

The patient underwent left frontotemporal craniotomy and gross total excision of the tumor. Intraoperatively, there was an extradural mass lesion compressing the left temporal lobe through a dural defect, and invading the bony structures including the foramen ovale and superior orbital fissure. The lateral part of the orbital wall was removed and the foramen ovale was widened. Post-op noncontrast CT (NCCT) showed good operative cavity ([Fig. 1F]). The patient was extubated on postoperative day 1 and was transferred back to the pulmonology unit. The postoperative neurological status was same as the preoperative status and no new neurological deficits developed.

A histopathological biopsy of the intracranial lesion showed malignant tumor cells with osteoid production and cartilaginous component ([Fig. 2A]).

Fig. 2 (A) Hematoxylin and eosin (H&E; ×400) shows malignant tumor cells with osteoid production (arrow) and cartilaginous component (arrowhead). (B) Immunohistochemistry (×400) shows SATB2 nuclear positive cells (osteogenic differentiation). (C) Immunohistochemistry (×400) shows SOX9 nuclear positive cells (cartilaginous component).

On immunohistochemistry, the cells were nuclear positive for SATB2 and SOX9 ([Fig. 2B] and [C]). The cartilaginous component was also positive for S-100. All these features are suggestive of cerebral metastatic deposit of chondroblastic osteosarcoma.

Postoperatively, the patient was started on cyclophosphamide, etoposide, and thalidomide-based chemotherapy. Contrast-enhanced MRI (CEMRI) of the brain done 2 months postoperatively showed no signs of residual or disease recurrence. At 6 months postpresentation, the patient had no new neurological deficits and had a Karnofsky performance status scale score of 80%, but at 8 months, postoperatively, the patient succumbed to disseminated extracranial disease.

 

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Discussion

Brain metastases are the most common type of brain tumor. Around 200,000 people are diagnosed with brain metastases in the United States every year.[4] The three most common tumors associated with brain metastases are the lung (20–56% of patients), breast (5–20%), and melanoma (7–16%).[5] It has been seen that nearly 3% of all brain metastases develop from sarcomas and 1 to 8% of all sarcoma patients develop brain metastases.[6] Sarcoma spreads to the brain hematogenously and via contiguous extension of metastases in cranial bones into intracranial structures.[7] Intracranial metastasis of osteosarcoma is rare and very few cases have been reported.[8] [9] [10] Doval et al reported a case of osteosarcoma of the femur in a middle-aged woman with a disease-free survival of more than 7 years, later presenting with brain metastases.[9] In a case reported by Soto et al, they demonstrated the first successful endovascular removal of a chondroblastic osteosarcoma embolus within the left middle cerebral artery.[10] Rabah et al reported a case of chondroblastic osteosarcoma of the right humerus presented with right frontal lobe metastasis in a 10-year-old girl.[8] The patient was given chemotherapy but died 14 months after her initial presentation. In a case report by Chang et al,[11] the authors described a subdural cerebral convexity “stony” osteosarcoma metastasis in which the patient underwent surgical resection but died after 5 months. These studies depict that central nervous system (CNS) metastasis of osteosarcoma is usually a preterminal event and portends poor survival of the patient. Preoperative absence of neurological deficits is of highest significance for survival rate after brain metastasis resection as suggested by Galicich et al.[12] Osteosarcoma with the lung as the primary site is further a rare entity, with very few case reports in the literature.[2] The median age of 67 years was reported by Huang et al[13] for primary pulmonary osteosarcoma. The median overall survival reported was 8 months. Large tumor size, metastases, pleural effusion, and microscopic findings of osteoid production were associated with overall survival. Radiotherapy did not seem to be effective, whereas chemotherapy predicted a better overall survival. Our patient had a very large lung tumor invading the surrounding structures with brain and pancreatic metastases. The resection of lung tumor was not feasible; hence, only chemotherapeutic drugs and palliative treatment were started. The overall prognosis of the patient appears to be dismal owing to the aggressive nature of the neoplasm. Chondroblastic osteosarcoma is a further aggressive variant of osteosarcoma associated with poor prognosis, high recurrence rate, and metastases. Chondroblastic osteosarcoma can be mistaken for chondrosarcoma, chondroblastoma, and chondroid chordoma.[14] Immunohistochemical studies aid in the diagnosis of chondroblastic osteosarcoma. S-100 protein and SOX9 expression can be used to identify tumors with chondrogenic differentiation, whereas SATB2 expression has been found to be a specific marker for osteoblastic differentiation. The biopsy of the metastases of our patient was positive for SOX9, S-100, and SATB2 markers further diagnosing chondroblastic osteosarcoma. Hence, this is an unusual case of primary lung chondroblastic osteosarcoma with brain metastases. MRI of the brain at regular intervals is essential in patients with osteosarcoma regardless of the primary site as early identification of the lesion followed by surgical resection before neurological deficits develop is the mainstay to improve survival if brain metastases occur.

 

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Conclusion

Chondroblastic osteosarcoma, a rare aggressive subtype of osteosarcoma, can rarely metastasize to the brain, typically portending a poor prognosis. This case highlights the diagnostic and therapeutic challenges in managing intracranial metastases. Multidisciplinary management, involving timely surgical intervention and appropriate adjuvant therapy, is crucial to improving survival and quality of life in such rare and aggressive presentations. Regular follow-up with imaging is essential for early detection and management of metastases.

 

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Conflict of Interest

None declared.

Ethical Approval Statement

All procedures in this study were performed in accordance with the ethical standards of the institution, based on the 1964 Declaration of Helsinki and its later amendments.

• References

• 1 Link MP, Gebhardt MC, Meyers PA. Osteosarcoma. In: Pizzo PA, Poplack DG. eds Principles & Practice of Paediatric Oncology. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2005: 1075-1113
• 2 Wagner MS, Reyes CV. Primary chondroblastic osteosarcoma of the lung. Sarcoma 1999; 3 (3–4): 193-195
• 3 Miller DL, Allen MS. Rare pulmonary neoplasms. Mayo Clin Proc 1993; 68 (05) 492-498
• 4 Gavrilovic IT, Posner JB. Brain metastases: epidemiology and pathophysiology. J Neurooncol 2005; 75 (01) 5-14
• 5 Nayak L, Lee EQ, Wen PY. Epidemiology of brain metastases. Curr Oncol Rep 2012; 14 (01) 48-54
• 6 Salvati M, D'Elia A, Frati A, Santoro A. Sarcoma metastatic to the brain: a series of 35 cases and considerations from 27 years of experience. J Neurooncol 2010; 98 (03) 373-377
• 7 Postovsky S, Ash S, Ramu IN. et al. Central nervous system involvement in children with sarcoma. Oncology 2003; 65 (02) 118-124
• 8 Rabah F, Al-Mashaikhi N, Beshlawi I. et al. Brain is not always the last fortress; osteosarcoma with large brain metastasis. J Pediatr Hematol Oncol 2013; 35 (02) e91-e93
• 9 Doval DC, Chacko M, Sinha R. et al. A rare case of brain metastasis in a patient with osteosarcoma. South Asian J Cancer 2017; 6 (01) 36-37
• 10 Soto JM, Reed LK, Benardete EA. Successful endovascular removal of a chondroblastic osteosarcoma embolus within the left middle cerebral artery. Proc Bayl Univ Med Cent 2020; 33 (03) 451-452
• 11 Chang JW, Howng SL, Sun ZM, Kuo TH, Duh CC. An unusual intracranial metastasis of osteosarcoma. Kao Hsiung I Hsueh Ko Hsueh Tsa Chih 1994; 10 (12) 700-704
• 12 Galicich JH, Sundaresan N, Arbit E, Passe S. . Surgical treatment of single brain metastases: factor associated with survival. Cancer 1980; 45 (02) 381-386
• 13 Huang W, Deng HY, Li D. et al. Characteristics and prognosis of primary pulmonary osteosarcoma: a pooled analysis. J Cardiothorac Surg 2022; 17 (01) 240
• 14 VandenBussche CJ, Sathiyamoorthy S, Wakely Jr PE, Ali SZ. Chondroblastic osteosarcoma: cytomorphologic characteristics and differential diagnosis on FNA. Cancer Cytopathol 2016; 124 (07) 493-500

Publication History

Article published online:
21 May 2025