Which of the following tumors is typically painful and slow-growing?

Adenoid cystic carcinoma is known for its characteristic clinical manifestations, including being painful and slow-growing. This type of tumor often arises in the salivary glands, particularly the submandibular gland and minor salivary glands, but can occur in other glands as well.

One of the defining aspects of adenoid cystic carcinoma is the unique pattern of growth, which can lead to nerve involvement. As it infiltrates surrounding tissues, patients frequently experience significant pain due to tumor expansion and nerve irritation. The slow growth rate of this tumor allows for a prolonged period before diagnosis, often contributing to the development of pain, as the tumor may not become noticeable until it reaches a considerable size.

In contrast, other tumors listed have different characteristics. For example, pleomorphic adenomas are typically painless and are considered benign, while Warthin tumors are usually asymptomatic and also benign. Mucoepidermoid tumors may present with varying degrees of pain but are generally not characterized by the same level of pain or slow growth that is associated with adenoid cystic carcinoma. In summary, the combination of pain and slow growth uniquely identifies adenoid cystic carcinoma in this question.