Sunitinib for refractory malignant pheochromocytoma: two case reports

Area of Science:

• Oncology
• Pharmacology

Background:

• Malignant pheochromocytoma is a rare cancer with limited treatment options.
• Molecular-targeted therapies like sunitinib are being investigated for their potential efficacy.

Observation:

• Two patients with refractory malignant pheochromocytoma received sunitinib after conventional chemotherapy.
• Tumor specimens showed partial expression of vascular endothelial growth factor (VEGF)-positive cells, indicating potential for targeted therapy.

Findings:

• Both patients achieved stable disease according to Response Evaluation Criteria in Solid Tumors 1.1.
• Overall survival was 13 and 8 months, with progression-free survival of 5 and 4 months, respectively.
• Adverse events included hypothyroidism, thrombocytopenia, anorexia, and general malaise, manageable with dose adjustments.

Implications:

• Sunitinib may be an effective treatment for malignant pheochromocytoma, especially in cases with VEGF-positive tumors.
• Further clinical studies are warranted to confirm sunitinib's efficacy and safety in a larger patient cohort.
• Targeted therapy based on immunohistochemical markers like VEGF could improve outcomes for rare endocrine tumors.