What are the other Names for this Condition? (Also known as/Synonyms)

• Adenomatosis of Minor Salivary Gland
• CanAd of Salivary Gland
• Salivary Gland Basal Cell Adenoma, Canalicular Type

What is Canalicular Adenoma of Salivary Gland? (Definition/Background Information)

• Canalicular Adenoma (CanAd) of Salivary Gland is a rare and benign tumor arising from salivary tissue (frequently from the minor salivary gland on the upper lip). It is mostly observed in adults over the age of 50 years
• The cause of formation of the tumor is unknown, and currently, no clearly-established risk factors for Canalicular Adenoma of Salivary Gland have been identified
• Most small tumors are asymptomatic and present no pain. In some cases, multiple canalicular adenomas are known to develop in the mouth
• The diagnosis of Canalicular Adenoma of Salivary Gland can be confirmed through a tissue biopsy. The treatment is a complete surgical removal of the tumor with adequate margins
• The prognosis of Canalicular Adenomas of Salivary Gland is typically excellent in most cases. Recurrence of the tumor following treatment is infrequent

Who gets Canalicular Adenoma of Salivary Gland? (Age and Sex Distribution)

• It is estimated that Canalicular Adenomas of Salivary Gland constitute about 6% of all benign salivary gland tumors
• It can be present in individuals between 33 and 91 years of age, but is usually diagnosed in the 7th decade (between 60-70 years) with an average age of diagnosis of 65 years
• The tumor is about 1.7-1.8 times more common in females than males
• The tumor may occur in all races and ethnic groups and no predilection is seen

What are the Risk Factors for Canalicular Adenoma of Salivary Gland? (Predisposing Factors)

• No clearly identified risk factors for Canalicular Adenomas of Salivary Glands have been established to date

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Canalicular Adenoma of Salivary Gland? (Etiology)

• Currently, the cause of development of Canalicular Adenoma of Salivary Gland is unknown
• They are believed to arise from duct cell abnormalities for yet unascertained reasons

What are the Signs and Symptoms of Canalicular Adenoma of the Salivary Gland?

The signs and symptoms of Canalicular Adenoma of Salivary Gland may include:

• Presence of a slow-growing, well-formed nodular mass in the mouth
• The tumor is known to form on the mucosal surface of the upper lip (in 8 out of 10 cases); the buccal mucosa (inner cheek lining) is affected in 1 out of 10 cases
• The overlying tumor surface may be reddish or bluish in appearance
• The tumor predominantly involves the minor salivary glands (CanAd constitute 20% of all minor salivary gland benign tumors); seldom, the major salivary glands are affected
• Sometimes, multiple canalicular adenomas are known to arise simultaneously, mostly affecting the upper lip and inner cheek lining
• Tumors of the palate are mostly seen in women
• The tumor size may range from 5-20 mm; in most cases, pain from the tumor is not observed
• Canalicular adenoma tumors may cause pain and discomfort; ulceration may be noted

How is Canalicular Adenoma of Salivary Gland Diagnosed?

The following exams and procedures may be used in the diagnosis of Canalicular Adenoma of Salivary Gland:

• Evaluation of the individual’s medical history and a through physical examination
• Plain X-ray of the head and neck region
• Ultrasound scan of the affected salivary gland
• CT or CAT scan with contrast of the head and neck usually shows a well-defined mass. This radiological procedure creates detailed 3-dimensional images of structures inside the scanned region
• MRI scans of head and neck region: A magnetic field is used to create high-quality pictures of certain parts of the body, such as tissues, muscles, nerves, and bones. These high-quality pictures may reveal the presence of the tumor

Although the above modalities can be used to make an initial diagnosis, a tissue biopsy of the tumor is necessary to make a definitive diagnosis to begin treatment. The tissue for diagnosis can be procured in multiple different ways which include:

• Fine needle aspiration (FNA) biopsy of the tumor: A FNA biopsy may not be helpful, because one may not be able to visualize the different morphological areas of the tumor. Hence, a FNA biopsy as a diagnostic tool has certain limitations, and an open surgical biopsy may be recommended.
• Salivary gland core biopsy of the tumor
• Salivary gland open biopsy of the tumor

Tissue biopsy:

• A tissue biopsy of the tumor is performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. Examination of the biopsy under a microscope by a pathologist is considered to be gold standard in arriving at a conclusive diagnosis
• Biopsy specimens are studied initially using Hematoxylin and Eosin staining. The pathologist then decides on additional studies depending on the clinical situation
• Sometimes, the pathologist may perform special studies, which may include immunohistochemical stains, molecular testing, and very rarely, electron microscopic studies to assist in the diagnosis

The differential diagnosis of a Canalicular Adenoma of Salivary Gland may include:

• Basal cell adenoma
• Adenoid cystic carcinoma

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Canalicular Adenoma of Salivary Gland?

Significant complications due to Canalicular Adenoma of Salivary Gland are generally not noted. In some cases, the following may be observed:

• Discomfort while speaking, eating, etc.
• The tumors are known to recur following surgical procedures to remove them
• The presence of multiple tumors can present treatment challenges
• Surgery to remove the tumor mass may result in facial nerve palsy (surgical complication)
• Post-surgical wound infection

How is Canalicular Adenoma of Salivary Gland Treated?

• A complete surgical excision with clear margins is the preferred mode of treatment of Canalicular Adenoma of Salivary Gland. This can result in a cure
• In some cases, radiation therapy may be necessary
• Post-operative care is important: One must maintain minimum activity levels, until the surgical wound heals
• Periodic follow-up is required; tumor recurrence is not very uncommon

How can Canalicular Adenoma of Salivary Gland be Prevented?

• Current medical research has not established a method of preventing the formation of Canalicular Adenoma of Salivary Gland
• Regular medical screening at periodic intervals with blood tests, radiological scans, and physical examinations, for those who have already endured the tumor, are helpful

What is the Prognosis of a Canalicular Adenoma of Salivary Gland? (Outcomes/Resolutions)

• The prognosis of Canalicular Adenoma of Salivary Gland is generally excellent with surgical intervention and complete removal, since it is a benign tumor
• The risk of tumor recurrence following surgery is minimal. However, the presence of multiple tumors may present additional difficulties and treatment challenges

Additional and Relevant Useful Information for Canalicular Adenoma of Salivary Gland:

There are 3 major types of salivary glands and these include the following:

• Parotid glands, found on the sides of the face
• Submandibular glands located at the back of mouth, on both sides of the jaw
• Sublingual glands that are seen under the floor of the mouth

The salivary glands produce saliva that helps in:

• Lubricating the mouth
• Swallowing
• Protects the teeth against bacteria
• Digestion of food