Radiation therapy for vulvar cancer uses high energy waves to kill cancer cells. It may help shrink a tumor so a doctor can surgically remove it, and it may help kill any cancer cells that remain after surgery.

Typically, people undergo both radiation therapy and chemotherapy during vulvar cancer treatment. Doctors may also recommend radiation therapy for those who cannot undergo surgery. The therapy generally lasts days to weeks.

This article discusses radiation therapy for vulvar cancer, including how it helps and when it is an option. It also examines the types, duration, and side effects of radiation therapy, as well as whether it affects fertility.

A note about sex and gender

Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.

A person lying down on a table entering a radiation machine for vulvar cancer.Share on Pinterest
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Vulvar cancer affects female external genitals, which include:

  • inner and outer vaginal lips, or labia
  • opening of the vagina and its glands
  • the clitoris
  • the mons pubis, which is the rounded area that covers the pubic bones

Vulvar cancer may develop on any of these parts. Radiation therapy uses high energy waves, such as X-rays, to damage or destroy these cancerous cells. It causes small breaks to occur in the DNA of the cells, which helps prevent them from growing and leads to cell death.

Although radiation can also affect nearby noncancerous cells, most recover afterward.

Doctors most frequently use radiation therapy in combination with chemotherapy when treating vulvar cancer. The chemotherapy allows the radiation to work more effectively.

The radiation can then shrink a more advanced tumor so that surgeons can remove it. The smaller size of the tumor may mean surgery causes less harm to the surrounding tissue.

Doctors may also use radiation:

  • after surgery to kill any cancer cells that may remain
  • alone or with chemotherapy to treat cancer in people who cannot have surgery
  • alone to treat lymph nodes in the pelvis and groin

According to the United Kingdom charity, Cancer Research UK, the use of radiation alone for vulvar cancer is uncommon.

There are two types of radiation therapy for vulvar cancer: external and internal.

The external variety involves the use of machines outside the body. There are two subtypes: 3D conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT).

3D-CRT uses special computers to map the tumor’s location. Afterward, the therapy shapes and aims radiation beams at the tumor from several directions.

IMRT uses a computer-driven machine that moves the person around as it emits radiation. It shapes the beams and aims them at the tumor from various angles. IMRT can also adjust the strength of the beams to protect nearby tissues from receiving too high of a dose.

The internal variety of radiation therapy involves placing an implant in the cancer site or surrounding tissue. This delivers a high dose of radiation to the cancer, with very little radiation reaching the surrounding tissues. It may help reduce tumor size and alleviate symptoms.

In general, it takes days or weeks of radiation therapy to damage the DNA sufficiently to cause the death of cancer cells. After the end of therapy, cancer cells will continue to die for weeks or months.

Common short-term side effects of radiation to the vulva include:

  • tiredness, which can become severe after a few weeks
  • skin changes, such as blistering
  • vulvar sensitivity and soreness
  • nausea, vomiting, and diarrhea
  • swelling in the legs
  • decreased red blood cell count, which can result in tiredness and shortness of breath
  • decreased white blood cell count, which increases the risk of serious infection
  • difficulty healing any surgical wounds if the radiation occurs after surgery

The side effects of radiation therapy can be worse if a person is undergoing both radiation and chemotherapy.

Some potential long-term side effects of radiation in general include:

  • increased skin sensitivity, including to sunlight
  • changes in how the skin feels to touch
  • changes in hair texture or color, or permanent hair loss
  • spider-like marks on the skin

If radiation causes changes to the skin of the vagina, it is also possible that this may affect sex after treatment.

Some people who receive radiation therapy to the pelvis stop having a monthly menstrual cycle. In some people, the menstrual cycle restarts after the end of radiation, but in others, it does not. This can be the result of ovarian failure.

If the menstrual cycle does not restart, a person will be unable to become pregnant. People who may want to become pregnant in the future need to discuss these risks with a doctor before starting treatment. There may be alternative methods of conception that people can consider if needed.

There are ways to alleviate or manage the side effects of radiation therapy. During treatment, it is advisable to:

  • wear loose clothes and soft materials
  • wash using only lukewarm water and mild soap
  • protect the area from sunlight
  • ask a doctor before shaving the area
  • ask a doctor before applying products to the area, such as creams, ointments, or oils

Do not:

  • wash or bathe in hot water
  • scratch or rub the area
  • expose the skin to sunlight
  • use any sticky bandages in the area

If a person needs a bandage, they should use paper tape and place it outside the area. When changing dressings, it is important to put the tape in a different place each time.

During external radiation treatment, it is generally safe to have sexual intercourse, but the side effects might make this uncomfortable. With external treatment, the radiation stays in the body, so it will not affect a partner.

People undergoing internal radiation may need to avoid sex temporarily. A person can ask a doctor what to do if they are unsure.

Radiation therapy for vulvar cancer causes small breaks in the DNA of tumor cells, which helps to kill them. Doctors can use radiation therapy in several ways. They may use it to shrink a tumor before surgical removal, to kill any cancer cells left behind after surgery, or as an alternative to surgery for those who cannot have it.

Radiation therapy can last days or weeks. It can cause short-term effects, such as tiredness and changes in blood cell counts. Long-term effects may include changes in skin or hair color and texture.

Self-care measures can help with managing the side effects of radiation treatment, and there are ways to plan for any potential long-term effects, such as reduced fertility. Speak with a doctor about this before treatment.