Top Line:Vestibular schwannomas are the most common tumors of the cerebellopontine angle, and most are small to medium with options for observation versus radiosurgery.
The Study: The prospective V-REX trial randomized 100 patients with newly-diagnosed unilateral vestibular schwannoma < 2 cm to upfront radiosurgery (12 Gy x 1 to 40-60% isodose line) versus surveillance imaging with treatment only upon growth. The primary endpoint was the ratio of tumor volume at 4 years to tumor volume at diagnosis. That ratio was 0.87 in the radiosurgery group versus 1.5 in the surveillance group, meaning tumors were an average of 50% larger than baseline at 4 years even with early treatment upon growth. On the one hand, 56% (n= 28) of patients in the surveillance group were without treatment at 4 years. On the other, receipt of radiation appeared to result in no clinically meaningful toxicity across a myriad of prospectively measured clinician and patient reported outcomes including audiovestibular testing. Which takes us back to the first hand, since the real goal of treatment is to preserve hearing. The mean deterioration at 4 years via audiometry was nearly identical: 18 dB in the upfront radiosurgery group and 20 dB in the surveillance group.
TBL: “Upfront radiosurgery demonstrated a significantly greater tumor volume reduction at 4 years compared with a wait-and-scan approach with treatment initiated upon tumor growth” with no discernible toxicity nor difference in hearing outcomes. | Dhayalan, JAMA 2023
The Study: The prospective V-REX trial randomized 100 patients with newly-diagnosed unilateral vestibular schwannoma < 2 cm to upfront radiosurgery (12 Gy x 1 to 40-60% isodose line) versus surveillance imaging with treatment only upon growth. The primary endpoint was the ratio of tumor volume at 4 years to tumor volume at diagnosis. That ratio was 0.87 in the radiosurgery group versus 1.5 in the surveillance group, meaning tumors were an average of 50% larger than baseline at 4 years even with early treatment upon growth. On the one hand, 56% (n= 28) of patients in the surveillance group were without treatment at 4 years. On the other, receipt of radiation appeared to result in no clinically meaningful toxicity across a myriad of prospectively measured clinician and patient reported outcomes including audiovestibular testing. Which takes us back to the first hand, since the real goal of treatment is to preserve hearing. The mean deterioration at 4 years via audiometry was nearly identical: 18 dB in the upfront radiosurgery group and 20 dB in the surveillance group.
TBL: “Upfront radiosurgery demonstrated a significantly greater tumor volume reduction at 4 years compared with a wait-and-scan approach with treatment initiated upon tumor growth” with no discernible toxicity nor difference in hearing outcomes. | Dhayalan, JAMA 2023