How would you treat esthesioneuroblastoma resected with focal microscopically positive margins in difficult to resect skull base regions?

Yes, it is often difficult to get negative microscopic margins in the anterior skull base in spite of combined ENT and neurosurgery approach. I would be comfortable at this stage to go ahead with adjuvant treatment. The dose of radiation in these situations with microscopic margins would be 70 Gy in 35 fractions to achieve durable local control. This being a T4/Kaddish C, I would treat the neck nodes prophylactically to at least 50 Gy based on the experience of University of Florida.

This is a very difficult area to re-resect. In most cases, this might require a combined ENT- Neurosurgery team approach for surgical resection and getting a final negative pathologic margin without knowing exactly where the microscopic residual cells are is near impossible.

I would just go ahead and treat with RT and consider boosting this area to a higher dose if possible with my normal tissue constraints.