Brachytherapy of vestibular schwannomas: report of three cases

Gamma knife and multileaf collimator LINAC have recently gained notoriety in the treatment of vestibular schwannomas. Without the use of gamma knife or LINAC, we have successfully pursued the 125-iodine interstitial irradiation of three vestibular schwannomas.

Up to March 2004, there was a 57 and 45 month follow-up period in two cases. One patient died of heart insufficiency 15 months after the brachytherapy. At the end of the follow-up period audiometric examinations revealed slight improvements of hearing in patients 1 and 2. In patient 1, the tumor volume measured was 4.06 mL on the control CT indicating a 40 % shrinkage in comparison to the 6.74 mL target volume at the brachytherapy. In patient 2, the tumor volume measured on the control MRI was 6.64 mL, indicating a 42 % shrinkage of the 11.45 mL target volume at the time of brachytherapy. Eleven months after the brachytherapy in patient 3 we found 10 % tumor shrinkage, a post-irradiation cyst developed inside the tumor and reached up to 35 % of the tumor volume.

In the treatment of three vestibular schwannomas we have used CT and image-fusion guided 125-iodine stereotactic brachytherapy.

Due to financial considerations, gamma knife and LINAC are not available for many countries and neurosurgical institutes. In the absence of the above-mentioned radiosurgical methods, we have shown brachytherapy as a new alternative and solution in the treatment of the three patients studied with vestibular schwannoma.