Gene expression-based prediction of pazopanib efficacy in sarcoma

Successful pazopanib treatment of undifferentiated pleomorphic sarcoma with coamplification of PDGFRA, VEGFR2 and KIT: A case report

Undifferentiated pleomorphic sarcoma (UPS) is a high-grade, aggressive soft tissue sarcoma (STS) with a poor prognosis, and no definitive or effective treatment is currently available for it. Pazopanib, an orally available multiple tyrosine kinase inhibitor, has been approved for the treatment of advanced STS. The present study documents the case of a 51-year-old man with advanced UPS with coamplification of platelet-derived growth factor receptor A (PDGFRA), vascular endothelial growth factor receptor 2 (VEGFR2) and stem cell factor receptor (KIT) genes. The patient exhibited a marked and sustained response to pazopanib. The patient presented with a retroperitoneal tumour with pancreatic head lymph node metastasis, and bone metastases in the second/fifth thoracic vertebrae and left femur. Based on the histological analysis of the retroperitoneal tumour and femoral mass, the patient was diagnosed with UPS. Palliative radiation therapy was administered to the left femur and second/fifth thoracic vertebrae to prevent fractures. After radiation therapy, the patient achieved a partial response after eight courses of doxorubicin. A comprehensive genomic profiling analysis (FoundationOne® CDx) revealed coamplification of PDGFRA, VEGFR2 and KIT genes. Hence, pazopanib was initiated as a second-line treatment. Notably, the retroperitoneal tumour shrank, and no new lesions developed for 3 years after the initiation of pazopanib treatment. This response suggests that the coamplification of PDGFRA, VEGFR2 and KIT may predict favourable outcomes in response to pazopanib.

Molecular Heterogeneity in Leiomyosarcoma and Implications for Personalised Medicine

OPINION STATEMENT

Leiomyosarcoma (LMS) is one of the more common subtypes of soft tissue sarcomas (STS), accounting for about 20% of cases. Differences in anatomical location, risk of recurrence and histomorphological variants contribute to the substantial clinical heterogeneity in survival outcomes and therapy responses observed in patients. There is therefore a need to move away from the current one-size-fits-all treatment approach towards a personalised strategy tailored for individual patients. Over the past decade, tissue profiling studies have revealed key genomic features and an additional layer of molecular heterogeneity among patients, with potential utility for optimal risk stratification and biomarker-matched therapies. Furthermore, recent studies investigating intratumour heterogeneity and tumour evolution patterns in LMS suggest some key features that may need to be taken into consideration when designing treatment strategies and clinical trials. Moving forward, national and international collaborative efforts to aggregate expertise, data, resources and tools are needed to achieve a step change in improving patient survival outcomes in this disease of unmet need.