May 14, 2017
2 min read

What is a cyst?

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A cyst is a closed sac with a defined membrane and division on the nearby tissue.

Cysts may contain fluid, air or semisolid material. Parasites — such as trichinosis, dog tapeworm and echinococcus — can form cysts within the muscles, liver, brain, lungs and eyes.

Types of cysts

There are various types of cysts. Common locations include in the skin, in the breasts, or on the ovaries, testes, kidneys or spine. Most cysts are benign. However, these masses sometimes may be considered neoplasms. Examples include dermoid, keratocyst or calcifying odontogenic cysts.

Ganglion cysts are common, noncancerous masses or lumps found in the hand. These cysts — which grow out of ligaments, tendon sheaths and joint linings — are filled with a thick fluid. The most common location is on the back of the wrist. However, they may appear in various places on and near the hand, such as at the end joint of a finger or at the base of a finger. Ganglion cysts may disappear or rapidly change size and can become larger with increased wrist activity, or they may become smaller with hand inactivity.

Sebaceous cysts are another common, noncancerous type of cyst. A foul odor may be secreted from the outside skin of the cyst. Sebaceous cysts grow slowly and usually are not painful; thus, treatment is rarely needed. However, options are available if these cysts become painful or have an unacceptable appearance.

What causes a cyst?

Common causes of cysts include infections or defects during fetal development.

Sebaceous cysts arise from sebaceous glands that secrete oily matter that lubricates the hair and skin. These cysts, which may be hereditary, are caused when glands or hair follicles become blocked. Trauma to the skin is another likely cause of a cyst. These cysts appear as small bumps beneath the skin. Although they can occur almost anywhere on the body, they typically appear on the face, neck and trunk.

Cyst on ovary

A cyst on the ovary is most commonly known as an ovarian cyst. These cysts appear as sacs filled with fluid and are located within or on the surface of an ovary.

A cyst on the ovary is a common occurrence for many women, as the normal function of the menstrual cycle typically causes these cysts, which are commonly referred to as functional. Ovaries create follicles each month which produce the hormones estrogen and progesterone. In some cases, a follicle continues to grow and turns into a functional cyst.  They rarely cause discomfort, are harmless and disappear with no treatment within a few months. However, in some cases, a cyst on the ovary can rupture and cause significant pain.

Cyst removal

A cyst may go away on its own or may require surgical removal.

A biopsy is required to determine whether a cyst is benign or malignant. When surgery is not indicated for cyst removal, physicians may prescribe antibiotics and pain-relieving medications.

Severe cysts may require lancing, the act of cutting the cyst open with a lancet or other sharp instrument, followed by treatment with sterile bandages and antibiotics.Secondary infections after lancing are of concern until the cyst has drained completely. Suspicious cysts are often diagnosed using needle aspiration. Fluids and substances drawn from a cyst are tested for infection and evidence of uncontrolled cell growth.

Epidermoid and pilar cysts, which originate in the skin and hair follicles, may cause lumps under the skin but often do not require surgical removal. Treatment for ganglion cysts typically is not necessary, but there are treatments available if the cyst becomes painful or has an unacceptable appearance.

There are three common cyst removal techniques specifically for sebaceous cysts — conventional wide excision, minimal excision and punch biopsy excision.

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