|LETTER TO EDITOR
|Year : 2020 | Volume
| Issue : 4 | Page : 886-887
Schwannoma of the head-and-neck: Is it always about surgery?
Department of Surgical Oncology, Head-and-Neck Services, Tata Memorial Hospital; Department of Surgical Oncology, Homi Bhabha National Institute, Mumbai, Maharashtra, India
|Date of Submission||19-Oct-2020|
|Date of Decision||13-Nov-2020|
|Date of Acceptance||15-Nov-2020|
|Date of Web Publication||25-Dec-2020|
Room 621, 6th Floor, Homi Bhabha Block, Tata Memorial Hospital, Dr. E Borges Road, Parel, Mumbai - 400 012, Maharashtra
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Vaish R. Schwannoma of the head-and-neck: Is it always about surgery?. Cancer Res Stat Treat 2020;3:886-7
Mohammad et al.'s article titled, “Schwannomas of the head and neck region: A report of two cases with a narrative review of the literature,” was an interesting read. The authors have described the various aspects of the management of schwannomas, suggesting surgery as the mainstay of treatment.
Surgery, however, is fraught with the danger of nerve palsy, and therefore, the patients should be chosen prudently weighing the benefit vis-a-vis the morbidity. Recently, the management philosophy has shifted toward observation in a select few cases. These tumors may arise from the cranial, peripheral, or autonomic nerves in the head-and-neck region, and a majority of them present as painless masses. The symptoms develop as these tumors grow and compress the nerve of origin and the surrounding structures. The nerve palsy is seldom a presenting complaint and results from an increase in the tumor size. Surgery is associated with significant morbidity due to the loss of nerve function. While it may be an acceptable treatment strategy for some peripheral nerve schwannomas, like those of the supraclavicular cervical plexus, due to the limited sensory deficit, it may result in a significant functional loss when the tumor originates from the vestibular or vagus nerve, the brachial plexus, or other cranial nerves.
Cord palsy is seen in <4% of the patients with vagal schwannoma as the presenting complaint. The estimated growth rate of these tumors is usually around 1–3 mm, meaning that these tumors will take years before they manifest compressive symptoms. Surgery offered to these patients may involve total tumor resection sacrificing the nerve fascicles of the origin or the more function preserving intracapsular enucleation. The latter ensures the preservation of anatomical integrity of the nerve but may still result in a deficit. Postoperative nerve palsy may occur in 35%-55% of the cases., Therefore, there is a role of judicious observation in the management of small asymptomatic tumors by serially monitoring their growth through imaging. This becomes even more important in the older patients and those who are unfit for anesthesia, precluding surgery as a safe option. However, the patients should undergo surgery upon documented tumor growth surge. There is an emerging role of intraoperative nerve monitoring (IONM), which can be either intermittent IONM (IIONM) or continuous IONM (CIONM) and helps preserve the nerve function. With the use of IONM, the incidence of cord paralysis has been reported to be <10%. The surgeon elicits a response using intermittent stimuli in IIONM, whereas the stimulus is continuous in CIONM. The loss of signal alerts the surgeon to a possible nerve injury and helps in the timely reversal of the step to avoid permanent loss of function. CIONM has the added advantage of function in real time, and hence, even the slightest insult causes a change in the signal alarming the surgeon.
Radiotherapy is an option when surgery is associated with very high morbidity. It has been tried in vestibular schwannomas mainly in the form of stereotactic radiosurgery as a tumoristatic approach, thus ceasing the tumor growth. It is a viable option in select cases, older patients, and those who are unfit for surgery due to comorbidities. Caution should be exercised when offering this approach to young patients as they will survive long to live with the sequelae of radiotherapy, and there is a rare concern of malignant transformation in these tumors.
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Conflicts of interest
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| References|| |
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