Erythrocytosis in Advanced Thyroid Cancer Therapy: Emerging Safety Concerns with Targeted Agents

Highlight

• Erythrocytosis, an increase in red blood cell mass, occurs in approximately 17.8% of patients with advanced thyroid cancer treated with antiangiogenic and targeted therapies.
• RET inhibitors show the highest incidence of therapy-induced erythrocytosis, signaling a specific safety concern with these agents.
• The hematologic abnormality is typically early in onset, recurrent, and manageable without significantly affecting survival or increasing vascular complications.
• Current management includes dose adjustments and occasionally phlebotomy, but standardized guidelines are lacking.

Study Background