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

• Epidermoid Papillary Adenoma of Salivary Gland
• Inverted Ductal Papilloma of Oral Cavity (IDPOC)
• Salivary Gland Inverted Ductal Papilloma

What is Inverted Ductal Papilloma of Salivary Gland? (Definition/Background Information)

• Inverted Ductal Papilloma (IDP) of Salivary Gland is a very rare and benign tumor arising from the salivary gland duct, usually from the region near the oral mucosa. It is a variant of ductal papilloma of salivary gland
• The cause of formation of IDP of Salivary Gland is unknown, and no risk factors have been clearly established. However, some studies inform that chronic injury to the mouth (lips or cheek) may have an important role in tumor formation
• Most tumors are solitary in nature, small, and asymptomatic. Inverted Ductal Papilloma of Salivary Gland typically arises from the minor salivary gland and presents as a mucosal nodule
• The diagnosis of Inverted Ductal Papilloma of Salivary Gland can be confirmed through a tissue biopsy. The treatment is a complete surgical removal of the tumor
• The prognosis of Inverted Ductal Papilloma of Salivary Gland is generally excellent in most cases, since it is a benign tumor. The tumor is not known to recur following its surgical removal

Who gets Inverted Ductal Papilloma of Salivary Gland? (Age and Sex Distribution)

• Inverted Ductal Papilloma of Salivary Gland is an extremely uncommon tumor
• It can be present in adults of a wide age range (between 27-77 years); but, is usually diagnosed in the 30-50 years’ period, with an average age of diagnosis of 44 years
• IDPs are seen in both males and females. Some studies indicate a preference for males
• The tumor can affect all races and ethnic groups

Currently, only a few cases of Salivary Gland Inverted Ductal Papilloma have been reported worldwide. Since the tumor is uncommon, there is only limited information available in the medical literature.

What are the Risk Factors for Inverted Ductal Papilloma of Salivary Gland? (Predisposing Factors)

• No clearly identified risk factors for Inverted Ductal Papilloma of Salivary Glands have been established to date
• Some researchers believe that the human papilloma virus (HPV) may play a contributory role towards tumor development
• Recurrent trauma to the oral cavity region may be a risk factor

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 Inverted Ductal Papilloma of Salivary Gland? (Etiology)

Currently, scientists do not know the factor(s) causing Inverted Ductal Papilloma of Salivary Gland.

• Some factors that may contribute towards tumor formation include HPV infection, and chiefly, injury to the oral cavity area
• Trauma to the lips or inner cheeks, may be chronic or longstanding; in some cases, a period of 3-6 years is recorded
• However, no definitive relationship between the above factors and tumor onset has been established so far

What are the Signs and Symptoms of Inverted Ductal Papilloma of Salivary Gland?

The signs and symptoms of Inverted Ductal Papilloma of Salivary Gland may include:

• Presence of a well-formed tumor mass in the mouth; often, the tumor is known to develop over many months and years
• In a majority of the cases, the tumor affects the minor salivary glands
• The tumor may appear as a mucosal nodule presenting no pain
• The surface of the tumor may appear punctured (like a small glossy bead with a tiny hole in the center)
• The common oral cavity areas involved include the lower lip, inner cheek lining (buccal mucosa), and the floor of the mouth
• Infrequently, the soft/hard palate and portion below the lower jaw gums (mandibular vestibule), are known to be affected
• The tumor size may range from 5-15 mm
• Occasionally, large tumors may cause pain and discomfort

How is Inverted Ductal Papilloma of Salivary Gland Diagnosed?

The following exams and procedures may be used in the diagnosis of Inverted Ductal Papilloma 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 an IDP of Salivary Gland may include:

• Mucoepidermoid carcinoma (MEC)
• Sialoadenoma papilliferum
• Intraductal papilloma

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 Inverted Ductal Papilloma of Salivary Gland?

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

• Discomfort while speaking, eating, etc.
• Surgery to remove the tumor mass may result in facial nerve palsy (surgical complication)
• Post-surgical wound infection

Tumor recurrence following surgery and a malignant transformation of Salivary Gland Inverted Ductal Papilloma have not been recorded.

How is Inverted Ductal Papilloma of Salivary Gland Treated?

• A complete surgical excision with clear margins is the preferred mode of treatment of Inverted Ductal Papilloma of Salivary Gland. This can result in a cure
• Surgical complications may be avoided to some extent through laser excision (using carbon-dioxide)
• Post-operative care is important: One must maintain minimum activity levels, until the surgical wound heals
• Follow-up following surgery/treatment is recommended

How can Inverted Ductal Papilloma of Salivary Gland be Prevented?

• Current medical research has not established a method of preventing the formation of Inverted Ductal Papilloma of Salivary Gland
• Regular medical screening at periodic intervals following treatment is beneficial

What is the Prognosis of Inverted Ductal Papilloma of Salivary Gland? (Outcomes/Resolutions)

• The prognosis of Inverted Ductal Papilloma 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

Additional and Relevant Useful Information for Inverted Ductal Papilloma 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