Palatal Schwannoma: An Analysis of 45 Literature Reports and of an Illustrative Case

Abstract

Introduction Schwannomas are benign tumors originating from differentiated Schwann cells. Being the least common intraoral neoplasm of neural origin, it is rarely seen in the palate. The literature lacks an extensive review of intraoral schwannoma confined to the palate. Objective To review previously reported cases of palatal schwannoma along with an illustrative case, and to provide a better insight regarding clinicopathological and radiological features of this neural tumor in a rare intraoral site. Data Synthesis We present a case of palatal schwannoma in a 16-year-old female. An additional 45 cases were identified in 2 medical database searches (PubMed and Google Scholar) published from the year 1985 onwards, and from 13 countries, in the 5 continents. The ages of the patients ranged from 3 to 84 years old. Palatal schwannoma showed a slight predilection to females, with a male/female ratio of ∼ 1:1.81. Hard palate involvement is almost twice greater than soft palate involvement. Surgical excision was employed in almost all of the cases, and recurrence was reported only once. Conclusion Palatal schwannomas, although rare, have been reported both over the hard and the soft palate. They mostly present as a painless, firm, well-encapsulated, slow-growing solitary lesion over the lateral palatal aspect.Imaging can add to suspicion and can delineate a differential diagnosis, but the diagnosis is confirmed by pathological examination. Fine-needle aspiration cytology (FNAC) is almost always inconclusive. Immunohistochemistry can assist in confirming a diagnosis, but is more important to rule out close differentials. Complete surgical excision is the treatment of choice, and recurrence or malignant transformation are extremely rare.

Soft palate resection and secondary healing not to impair the velopharyngeal function? – Diagnosis and treatment of an intraoral schwannoma: A case report

“…Kun et al found the correct preoperative diagnosis of 4 out of 49 cases with CT and MRI and stated that a diagnosis based on radiographic findings is hard to state [ 14 ]. To secure histology, fine needle aspiration is inconclusive [ 15 ] in most cases, whereas Immunohistochemistry can rule out differential diagnosis [ 6 ]. As we didn’t know the entity of the tumor and couldn’t rule out malignancy, our workup started with a CT scan to sort out an infiltration ( Fig.…”

“…Surgical excision is the treatment of choice in neurogenic tumors of the palate, recurrence is possible and malignant transformation is described as extremely rare [ 6 , 14 ]. In the present case we could prove a non in sano resection after the first surgical excision, therefore we conducted a Re-resection with clear margins leaving a muscle mucosal defect of 30 mm diameter.…”

“…This entity seems to mostly occur in the head and neck [ 4 ], approximately 25–45% of all schwannomas seem to affect this anatomic region [ 5 ]. Overall neurogenic tumors are the least common intraoral lesions [ 6 ].…”

“…Appearance on the soft or hard palate is classified as not commonly seen [ 10 ]. The hard palate is more commonly affected, one-third of the palatinal lesions affect the soft palate [ 6 ]. Normally, these tumors present as painless asymptomatic masses but can be oligosymptomatic due to the region of origin.…”

IAO Systematic Review Award 2020

“… 1 In 2020, it was awarded to the three best systematic and/or literature reviews that were published in the journal in the year 2019. 2 3 4 This award was established to encourage the submission of high-quality systematic review articles.…”