American Board of Surgery Qualifying Exam (ABS QE) Practice Test

Which of the following is known as the most common malignant tumor of the salivary gland?

1. Adenoid cystic carcinoma

2. Pleomorphic adenoma

3. Mucoepidermoid carcinoma

4. Warthin's tumor

The correct answer is: Mucoepidermoid carcinoma

Mucoepidermoid carcinoma is recognized as the most common malignant tumor of the salivary glands. This type of cancer primarily arises in the major salivary glands, particularly the parotid gland, but it can also occur in minor salivary glands throughout the oral cavity. In understanding why mucoepidermoid carcinoma holds this distinction, it’s essential to consider its prevalence and typical presentation. It tends to occur in a wide age range but is particularly noted for affecting younger individuals. The tumor is characterized by a mixture of mucin-secreting cells and epidermoid (squamous) cells, which is reflective of its name and contributes to its classification. While adenoid cystic carcinoma is another significant type of salivary gland malignancy, it is less common overall when compared to mucoepidermoid carcinoma. Pleomorphic adenoma, on the other hand, is actually the most common benign tumor of the salivary glands, and thus not classified as malignant. Warthin's tumor, also benign, is more prevalent in specific demographic groups (like smokers) and does not meet the criterion for the most common malignant tumor. Therefore, the answer is rooted in the actual incidence and classification of