Cutaneous endometriosis is a rare condition where endometrial tissue grows in areas outside of the uterus. Endometrial tissue may grow on the skin, which can cause lesions, swelling, discomfort, and bleeding.

Cutaneous endometriosis is a type of endometriosis that occurs on a person’s skin. A person may develop skin lesions around their belly button or other areas.

There are primary and secondary types. The primary type occurs spontaneously, while the secondary type occurs following a surgical procedure.

This article reviews what cutaneous endometriosis is, its possible causes, its symptoms, and more.

A person in activewear standing in a forest. Cutaneous endometriosis is a rare condition where endometrial lesions occur on the skin.Share on Pinterest
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Endometriosis is a condition in which endometrial cells grow outside the uterine cavity or uterus.

Cutaneous endometriosis is a type of extrapelvic endometriosis, meaning the endometrial cells grow outside of the pelvic region. “Cutaneous” refers to the skin, indicating that the growths occur on the skin.

It is also known as “scar endometriosis,” as it is common for cutaneous endometriosis to occur at the site of a surgical incision from a previous abdominal or gynecological surgery.

Other common locations include:

  • the abdominal wall
  • navel
  • vulva
  • the extremities (hands and feet)

Endometriosis is relatively common, affecting 5–15% of women in their reproductive years. Cutaneous endometriosis affects about 0.5% to 1% of these cases, making it a rare form of the condition.

There are two types of cutaneous endometriosis: primary and secondary.

Primary cutaneous endometriosis occurs spontaneously. The underlying causes are unknown.

Theories as to how the primary condition occurs date back about 100 years. Experts think the following mechanisms may be responsible for the movement of the endometrial tissue to the skin:

  • Cellular metaplasia: This is the replacement of one cell type with another cell type in the same tissue. In this instance, skin cells become endometrial cells.
  • Vascular migration: Endometrial cells are dispersed through the vascular (blood vessel) system.
  • Lymphatic migration: Endometrial cells are dispersed through the lymphatic system (a series of tubes and lymph nodes that are spread throughout the body).

Secondary cutaneous endometriosis likely occurs due to “seeding” following pelvic surgery. This is where endometrial tissue inadvertently gets planted on the skin. The average time of onset following surgical procedures is about 4.2 years.

Learn more about the causes of endometriosis.

Symptoms of cutaneous endometriosis often correspond with the menstrual cycle. They can include:

Diagnosis often starts with a visit to a healthcare professional. A person should go prepared to discuss their symptoms as well as past medical procedures that may assist a healthcare professional in determining the underlying cause.

If the healthcare professional suspects cutaneous endometriosis, they may confirm the diagnosis with a biopsy of the affected skin that they can then examine under a microscope.

They will likely ask about previous surgeries to help determine whether it is primary or secondary cutaneous endometriosis. They may also order a CT scan or MRI scan to help rule out cutaneous metastases of a tumor.

About 14% of people found to have cutaneous endometriosis also end up having pelvic endometriosis, which means a person may need additional testing to check for this.

Learn more about endometriosis diagnosis.

Treatment typically involves the use of hormone therapy or surgery. A healthcare professional may also recommend pain management, which may include the use of nonsteroidal anti-inflammatory drugs (NSAIDs).

Hormone therapy

Hormone therapy can help shrink the size of the lesion and reduce symptoms. It may be an appropriate choice for people who do not want surgery or who also have pelvic endometriosis. If hormone treatment stops, the lesion can return or get larger.

Healthcare professionals typically provide a consultation before hormone treatment due to the potential for side effects, which can include weight gain and acne.

Hormones used may include:

  • danazol
  • progesterone
  • gonadotropin-releasing hormone (GnRH)
  • combined oral contraceptive pill

Learn more about the best medication for endometriosis.


Surgical removal of the lesion is generally the preferred choice in treatment. During surgical removal, the surgeon removes a large patch of skin from around the lesion to ensure it does not return.

In some cases, a healthcare professional may recommend hormone therapy following surgery to help prevent it from coming back.

Learn more about surgery for endometriosis.

Cutaneous endometriosis is generally benign, but it can lead to cancer in some cases.

The exact cause of cancer in people with cutaneous endometriosis, and the number of people this occurs in, is unclear.

There is also a possibility of endometriosis skin lesions reoccurring in the same area after surgery.

People should speak with a healthcare professional if they develop a lesion on their skin that they cannot explain. Healthcare professionals may be able to help diagnose and determine the cause of the lesion on the skin.

A person may suspect cutaneous endometriosis if they notice symptoms worsening around their menstrual period or if a skin lesion develops a few years following pelvic surgery.

With surgical removal, the outlook for people with cutaneous endometriosis is generally good.

The chance of recurrence is low. In a small 2018 study, only 3 of 33 people had a recurrence following their surgery.

Cutaneous endometriosis is a subtype of endometriosis in which endometrial tissue grows on the skin. It causes lesions to form, often around the belly button and groin, that may get worse during a menstrual period.

Once diagnosed, the condition typically requires surgical removal, possibly with follow-up hormonal care. This can help prevent recurrence in the future.

The outlook is generally good, though it may develop into cancer in some people.