From the Guidelines
The correct answer is (e) pleomorphic adenoma is the most common parotid neoplasm. Pleomorphic adenoma accounts for approximately 60-70% of all parotid gland tumors, making it by far the most common tumor type in this location, as stated in the study by 1. It is a benign tumor characterized by mixed epithelial and mesenchymal components, which gives it the name "pleomorphic." Regarding the other options:
- Core biopsy is not routinely required before resection as fine needle aspiration is often sufficient for diagnosis.
- Enucleation is inadequate treatment as it leads to high recurrence rates; instead, superficial parotidectomy with preservation of the facial nerve is the standard approach, as supported by the management guidelines for salivary gland malignancy 1.
- Malignant transformation occurs in only about 6% of cases, typically in long-standing or recurrent tumors, so it is not considered common.
- Facial nerve palsy is an uncommon complication of the tumor itself, though it can be a surgical complication during parotidectomy, as mentioned in the study by 1. The facial nerve is typically preserved during surgery unless there is direct tumor involvement. Some key points to consider when managing pleomorphic adenoma include:
- The importance of complete excision to prevent recurrence
- The need to balance tumor removal with preservation of the facial nerve
- The low risk of malignant transformation and facial nerve palsy associated with this tumor type, as discussed in the study by 1.
From the Research
Pleomorphic Parotid Adenoma Characteristics
- Pleomorphic adenoma is a slow-growing benign salivary tumour most commonly arising in the parotid gland 2.
- It is the most common tumour of the parotid gland 3.
Treatment Options
- Enucleation is associated with high recurrence rate 2.
- Partial superficial parotidectomy is a safe treatment for parotid pleomorphic adenomas with relatively few postoperative complications 4.
- Formal parotidectomy or limited surgery are also options, with advantages and disadvantages for each approach 5.
Complications and Recurrence
- Recurrence, or more accurately residual disease, is thought to be due to small islands of tumour which can be left behind at surgery 2.
- The risk of recurrence is higher when the initial operation was done at a young age, after enucleation, and if the initial margins were invaded 3.
- Transient and permanent facial nerve paralysis can occur, but the rates are relatively low with proper surgical techniques 4, 6.