Khattab, Mohamed H.

Objective: To report and discuss the effectiveness of stereotactic radiosurgery (SRS) or fractionated radiotherapy (FRT) for tumor control following surgical resection of endolymphatic sac tumors (ELST). Study Design: Retrospective case series. Setting: Multi-institutional academic referral centers. Patients: Patients undergoing surgical resection for ELST followed by SRS or FRT. Intervention(s): Surgical resection followed by radiotherapy. Main Outcome Measures: Local tumor control. Results: Two of the five patients experienced tumor recurrence after gross total microsurgical at 78 and 11 months, respectively. The former patient received salvage 3D conformal radiotherapy (3D-CRT) and while the latter patient underwent three courses of salvage SRS for recurrence, two of which were in-field and was disease-free at last follow up. Two additional patients underwent subtotal tumor resection (STR) followed by intensity-modulated radiation therapy (IMRT) and are currently without disease. One patient underwent STR followed by proton-beam therapy (PBT) and was free of disease at most recent follow-up. Conclusion: SRS/FRT remains a useful adjuvant for treatment of residual or recurrent ELSTs, where the risk of revision microsurgical resection is high.