Mucous Cyst: Symptoms, Causes, Diagnosis, and Treatment

A mucous cyst occurs as a benign, fluid-filled mass. It most often appears on your lower lip or in or around other parts of your mouth. It can also grow on a finger or toe.

A mucous cyst is not considered a sign or risk of cancer. When it appears in your mouth, it can occur due to trauma, bad oral habits, or an obstruction or blockage of a salivary duct. A mucous cyst on your finger is often linked to joint wear and tear common in osteoarthritis.

Some mucous cysts may not need treatment. It is common for these types of cysts to resolve on their own. When treatment is needed due to recurrence or pain, it often involves the surgical removal of the cyst.

This article describes mucous cyst causes, symptoms, treatment, and outlook.

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There are two types of mucous cysts. Their location classifies them:

Oral Mucous Cyst

The most common type of an oral mucous cyst is called a mucocele. It appears on your lip or mouth when mucus clogs a salivary gland. It most often affects people between 10 and 20 years of age.

There are two types of oral mucous cysts:

Extravasation types of oral mucous cysts are more common than retention types.

Digital Mucous Cyst

A digital mucous cyst occurs near the joints of your fingers or toes. It most often affects older adults in their 70s. There are two types of digital mucous cysts:

Symptoms of a mucous cyst vary based on the location of the mass. The following symptoms are most common:

Oral Mucous Cyst:

Digital Mucous Cyst:

Symptoms of a digital mucous cyst that forms near the joints of your fingers include the following:

Symptoms of a digital mucous cyst that forms near the base of a fingernail or toenail include the following:

Causes of a mucous cyst vary based on the cyst type. Some mucous cysts form at random for no apparent reason. The risk of developing cysts can be reduced by avoiding certain behaviors.

Oral Mucous Cysts:

Extravasation oral mucous cysts:

Retention mucous cysts:

Digital Mucous Cysts:

While the causes of digital mucous cysts are unknown, these cysts are linked to degenerative changes of the connective tissue in the distal interphalangeal joint (the hinge joint closest to the tip of your finger). This wear and tear is usually caused by osteoarthritis.

The diagnosis of mucous cysts varies by type of cyst.

Oral Mucous Cysts:

An objective examination and case history are critical for diagnosing mucous cysts. In some cases, diagnosis may require one or more of the following procedures:

Digital Mucous Cysts:

Diagnosis of digital mucous cysts can usually be accomplished without imaging studies. A clinical diagnosis based on your health history, a physical exam, and symptoms usually provides adequate information for confirming a mucous cyst.

A mucous cyst may resolve on its own, though the condition often requires treatment. Surgical removal of an oral or digital mucous cyst is regarded as the most effective treatment because it presents the lowest chance of recurrence.

In some cases, surgical removal of a mucous cyst may require the removal of an excessive amount of accompanying tissue. For this or other reasons, your healthcare provider may advise one of the following conservative therapies to treat a mucous cyst:

It would be best never to attempt to puncture and drain a mucous cyst yourself. Doing so can spread infection and damage to the surrounding tissue. Only a healthcare provider can safely treat or remove a mucous cyst.

The prognosis for an oral or digital mucous cyst is generally good when treated with surgical removal. Without treatment, larger oral mucous cysts may interfere with speech and chewing. In addition, larger digital mucous cysts may hinder normal movement and range of motion if left alone.

Complete surgical removal of an oral or digital mucous cyst is often the preferred treatment method. This type of procedure typically presents the lowest chance of recurrence.

Recovery from surgical removal of a mucous cyst can take about two weeks, with times varying based on the location and size of the cyst removed. Physical therapy to restore strength and normal movement of the affected finger may be necessary after the surgical removal of a digital mucous cyst.

If you have an oral mucous cyst attributed to habits like lip biting or lip sucking, you may have to work to avoid these behaviors to prevent the recurrence of another mucous cyst.

If your digital mucous cyst was linked to a first-time diagnosis of osteoarthritis, you might have to undergo further diagnostic tests to determine the extent of joint damage present.

A mucous cyst is a fluid-filled mass that forms on your lip, in or around your mouth. It can also develop on a finger or toe.

While this type of cyst is often harmless, an untreated oral mucous cyst can grow and hinder normal speaking and chewing. Without treatment, a digital mucous cyst can affect the affected finger's normal movement and range of motion.

While you can't prevent a mucous cyst, bad habits like lip biting or lip sucking can increase your risk of having one in your mouth. Osteoarthritis is linked with a higher risk of a mucous cyst on your finger. Surgery for a mucous cyst offers the best treatment to prevent it from returning.

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By Anna GiorgiAnna Zernone Giorgi is a writer who specializes in health and lifestyle topics. Her experience includes over 25 years of writing on health and wellness-related subjects for consumers and medical professionals, in addition to holding positions in healthcare communications.