Pleomorphic adenoma, also known as a benign mixed tumor, is the most common neoplasm of the salivary glands. However, its occurrence in the nasal cavity, especially in the nasal septum, is exceedingly rare. When it does arise in such an unusual site, it poses unique challenges in diagnosis and treatment due to its atypical presentation. This article presents a case of giant pleomorphic adenoma in the nasal septum, exploring clinical findings, imaging results, treatment, and follow-up to provide insight for clinicians and researchers alike.
Introduction
Pleomorphic adenomas most frequently affect the parotid gland, but minor salivary glands—such as those in the palate, lips, and nasal cavity—may also be involved. Intranasal pleomorphic adenomas account for less than 1% of all benign salivary gland tumors, making them a rare but important differential diagnosis for nasal masses.
These tumors are typically slow-growing, painless, and well-circumscribed, but when located in the nasal septum, they may grow undetected until they reach significant size and cause obstructive symptoms. Delayed diagnosis may lead to complications and more complex surgical intervention.
Case Presentation
Patient Profile
A 46-year-old female presented to the ENT clinic with progressive nasal obstruction on the right side, which had been ongoing for over a year. She also reported intermittent epistaxis (nosebleeds) and hyposmia (reduced sense of smell). There was no history of facial pain, weight loss, or systemic illness. Her medical history was unremarkable, and there was no history of prior nasal surgeries or trauma.
Clinical Examination
Anterior rhinoscopy revealed a large, smooth, lobulated mass filling the right nasal cavity, deviating the septum to the left. The mass appeared non-tender, non-ulcerated, and bled mildly on contact. There was no cervical lymphadenopathy or signs of cranial nerve involvement.
Imaging Studies
A CT scan of the paranasal sinuses showed a well-defined, expansile soft-tissue mass originating from the nasal septum, extending into the nasal cavity and displacing adjacent structures without bony erosion. MRI demonstrated intermediate signal intensity on T1-weighted images and heterogeneous enhancement with contrast, suggestive of a benign neoplasm.
Differential Diagnosis
The radiologic and clinical findings prompted consideration of several possibilities:
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Inverted papilloma
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Nasal polyps
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Schwannoma
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Angiofibroma
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Pleomorphic adenoma
Given the mass’s location, slow progression, and well-circumscribed nature, a pleomorphic adenoma was considered likely but required histopathological confirmation.
Surgical Intervention
The patient underwent endoscopic endonasal excision of the tumor under general anesthesia. Intraoperatively, the mass was found to be originating from the posterior nasal septum, firmly attached but encapsulated. A wide local excision was performed to ensure clear margins. Minimal bleeding occurred, and the septum was reconstructed using local mucosal flaps.
Histopathological Findings
Microscopic examination revealed features consistent with pleomorphic adenoma, including:
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Mixed epithelial and myoepithelial cell components
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Areas of chondromyxoid stroma
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Absence of cellular atypia or mitotic activity
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No evidence of malignant transformation
These findings confirmed the diagnosis of benign pleomorphic adenoma originating from ectopic minor salivary gland tissue in the nasal septum.
Postoperative Outcome
The patient’s recovery was uneventful. At a 3-month follow-up, she reported complete resolution of nasal obstruction and no further episodes of epistaxis. Nasal endoscopy revealed good healing and no evidence of recurrence. She continues to be monitored every six months.
Discussion
Rarity and Diagnostic Challenges
Pleomorphic adenoma in the nasal septum is a rare entity, with less than 100 cases reported in literature. Its unusual location often delays diagnosis, as symptoms mimic common nasal pathologies like polyps or chronic rhinosinusitis.
The key distinguishing features include:
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Unilateral nasal obstruction
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Epistaxis or bleeding
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Lack of response to decongestants or steroids
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Mass localized to the septum with non-aggressive behavior on imaging
Pathogenesis
The origin of nasal pleomorphic adenomas is thought to be from ectopic salivary gland tissue present in the respiratory mucosa, particularly in the septum and lateral nasal wall. Although benign, these tumors must be managed carefully due to their potential for recurrence and, rarely, malignant transformation (carcinoma ex pleomorphic adenoma).
Treatment
Complete surgical excision with clear margins is the treatment of choice. Endoscopic approaches have proven effective for accessible tumors, minimizing external scars and reducing morbidity. Histological examination is mandatory to rule out malignancy.
Long-term follow-up is essential, as recurrence can occur years after the initial surgery, especially in cases with incomplete resection or capsular rupture.
Conclusion
This case highlights a rare but significant presentation of giant pleomorphic adenoma in the nasal septum. Awareness of such uncommon tumor locations is vital for timely diagnosis and appropriate surgical management. With proper excision and surveillance, patients can expect excellent outcomes and a low risk of recurrence.