Gamma Knife radiosurgery of olfactory groove meningiomas provides a method to preserve subjective olfactory function
- 292 Downloads
Anosmia is a common outcome after resection of olfactory groove meningioma(s) (OGM) and for some patients represents a significant disability. To evaluate long term tumor control rates and preservation of subjective olfaction after Gamma Knife (GK) stereotactic radiosurgery (SRS) of OGM. We performed a retrospective chart review and telephone assessments of 41 patients who underwent GK SRS between 1987 and 2008. Clinical outcomes were stratified by full, partial or no subjective olfaction, whereas tumor control was assessed by changes in volume greater or lesser than 25 %. The median clinical and imaging follow-up were 76 and 65 months, respectively. Prior to SRS, 19 (46 %) patients had surgical resections and two (5 %) had received fractionated radiation therapy. Twenty four patients (59 %) reported a normal sense of smell, 12 (29 %) reported a reduced sense of smell and five (12 %) had complete anosmia. The median tumor volume was 8.5 cm3 (range 0.6–56.1), the mean radiation dose at the tumor margin was 13 Gy (range 10–20) and the median estimated dose to the olfactory nerve was 5.1 Gy (range 1.1–18.1). At follow-up, 27 patients (66 %) reported intact olfaction (three (7 %) described return to a normal sense of smell), nine (22 %) described partial anosmia, and five (12 %) had complete anosmia. No patient reported deterioration in olfaction after SRS. Thirteen patients (32 %) showed significant tumor regression, 26 (63 %) had no further growth and two (5 %) had progressed. The progression free tumor control rates were 97 % at 1 year and 95 % at 2, 10 and 20 years. Symptomatic adverse radiation effects occurred in three (7 %) patients. Stereotactic radiosurgery provided both long term tumor control and preservation of olfaction.
KeywordsOlfactory groove Meningioma Anosmia Radiosurgery Outcomes Tumor control
The authors thank Professor Douglas Kondziolka, MD (New York University Langone Medical Center) for significant contribution to patient management at University of Pittsburgh. This study was presented at the 2013 International Stereotactic Radiosurgery Society Congress.
Conflict of interest
Dr. Lunsford is a consultant and stock holder with AB Elekta.
- 10.Romani R, Lehecka M, Gaal E, Toninelli S, Celik O, Niemela M, Porras M, Jaaskelainen J, Hernesniemi J (2009) Lateral supraorbital approach applied to olfactory groove meningiomas: experience with 66 consecutive patients. Neurosurg 65:39–52. doi: 10.1227/01.NEU.0000346266.69493.88 CrossRefGoogle Scholar
- 11.Dm L (1989) Meningiomas of the olfactory groove and anterior fossa. Williams & Wilkins, PhiladelphiaGoogle Scholar
- 19.Durante F (1885) Estirpazione di un tumore endocranico. Arch Soc ital Chir 2:252–255Google Scholar