Never too young for a salivary gland carcinoma ex-pleomorphic adenoma

• Published in: The Egyptian journal of otolaryngology Vol. 40; no. 1; pp. 15 - 6
• Main Authors: Fuad, Ahmad Muizzuddin Ahmad, Guan, Lum Sai, Yunus, Mohd Razif Mohamad
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-12-2024; Springer; Springer Nature B.V; SpringerOpen
• Subjects: Adenoma; Biopsy; Cancer; Carcinoma; Carcinoma ex-pleomorphic adenoma; Carotid arteries; Cartilage; Case Report; Cellular biology; CXPA; Exocrine glands; Malignant transformation; Medical imaging; Medicine; Medicine & Public Health; Neck; Oral cancer; Pleomorphic adenoma; Salivary gland neoplasms; Skin; Submandibular glands; Surgery; Tumors; Ultrasonic imaging; CXPA; Carcinoma ex-pleomorphic adenoma; Salivary gland neoplasms; Pleomorphic adenoma; Malignant transformation; Submandibular glands
• ISSN: 2090-8539; 1012-5574; 2090-8539
• DOI: 10.1186/s43163-024-00575-8

Background
Carcinoma ex-pleomorphic adenoma (CXPA) can either arise primarily as a de novo or from the malignant transformation of a benign pleomorphic adenoma (PA). CXPA mostly occurs in adults aged 50 to 70 years; hence, the occurrence of CXPA in younger ages is not common.
Case presentation
We report a 27-year-old female who had a history of submandibulectomy for pleomorphic adenoma, and presented with recurrent left submandibular swelling for 4 months. The mass was rapidly increasing in size and was associated with occasional throbbing pain. Examination showed a multilobulated, firm left submandibular swelling with no overlying skin changes. FNAC was performed twice, by conventional and ultrasound-guided techniques, and both concluded as benign salivary gland tumours. CT scan and MRI revealed a well-demarcated tumour with an area of necrosis within, with no obvious invasion into surrounding soft tissue and no significant lymphadenopathy. Having high suspicion of a malignant transformation, the tumour was resected with a concurrent modified radical neck dissection. The histopathological examination confirmed a carcinoma ex-pleomorphic adenoma with the myoepithelial malignant component. The patient subsequently received adjuvant radiotherapy. This case demonstrated that CXPA, although rare, can occur in young adults. Pre-operative FNAC and radiological imaging may mimic a pleomorphic adenoma.
Conclusion
The presence of recurrent tumours with rapid growth should alarm the clinician about a possible malignant transformation of a benign parotid tumour.