Published online Oct 18, 2021. doi: 10.5312/wjo.v12.i10.760
Peer-review started: February 5, 2021
First decision: May 3, 2021
Revised: May 16, 2021
Accepted: September 8, 2021
Article in press: September 8, 2021
Published online: October 18, 2021
Processing time: 250 Days and 16.5 Hours
Schwannomas are one of the most common benign tumors in the peripheral nervous system and symptoms described in the literature are mainly sensory as radiating pain, local irritation, and sensation of a heavy mass, while primary motor involvement leading to paresis is uncommon.
Surgical removal of schwannomas in the peripheral nervous system is by many surgeons considered a high risk procedure with surgery directly on peripheral nerves and since the literature regarding the clinical results that can be expected after this procedure is relatively sparse, we found it of interest to examine the postoperative results after this procedure.
To evaluate the pre- and postoperative symptoms in patients treated surgically for benign schwannomas and examine whether tumor size, anatomical location or specific nerve location had an impact on the clinical symptoms prior to and after surgery. Finally, we also aimed to investigate the rate of malignant transformation.
All patients who had surgery due to benign schwannomas from May 1997 to January 2018 at our institution were identified and included in the study. We registered preoperative baseline data and postoperative symptoms and objective findings were recovered from patient records and a questionnaire. Patients that reported new symptoms, recurrence of a mass, or unsatisfactory results were offered an magnetic resonance imaging-scanning and a follow-up to rule out a recurrence or malignant transformation of the tumor.
At the end of follow-up we recorded a significant post-operative decrease in clinical symptoms such as local pain and radiating pain. Multivariate analysis showed that tumors located within minor nerves had a significantly higher prevalence of postoperative symptoms compared with tumors in major nerves. One patient with schwannoma diagnosed initially by needle biopsy was diagnosed to have malignant transformation diagnosed in the surgically removed tumor. No local recurrences were reported.
Surgery of schwannomas can be conducted with low risk of postoperative complications, acceptable decrease in clinical symptoms and risk of local recurrence and malignant transformation is low.
Future studies should provide prospective data and especially give more detailed information for those few patients who got worsening of their pre-operative symptoms and give further information about the specific characteristics of the patient and the tumor that may affect the outcome of the surgical tumor removal.