After surgery for endometrial (womb or uterine) cancer, some people are offered a short course of internal radiotherapy to the top of the vagina. It goes by several names: vaginal cuff brachytherapy, vaginal vault brachytherapy or simply vaginal brachytherapy (VBT). They describe the same treatment.
Compared with other forms of brachytherapy it is a relatively simple procedure. The American Cancer Society describes the applicator as feeling "a lot like a snug tampon", and Cancer Research UK says the applicator "should not be painful". Most people have it as an outpatient and go home the same day.
This guide explains why the vaginal cuff is treated, who tends to be offered it, what a session involves, how many treatments to expect, and what the side effects are. It is general information drawn from the sources listed at the end, not advice about your own treatment.
What the "vaginal cuff" is and why it is treated
When the uterus and cervix are removed in a hysterectomy, the surgeon closes the top of the vagina. That closed end is called the vaginal cuff (or vaginal vault). It is not a separate organ — just the new top of the vagina.
Why treat it? In the PORTEC-2 trial report, published in The Lancet, the investigators note that after surgery for intermediate-risk endometrial cancer "the vagina is the most frequent site of recurrence". Brachytherapy aims a dose at the upper vagina, where those recurrences tend to occur, while giving the bladder and rectum less. The American Cancer Society explains that "the radiation mainly affects the area of the vagina in contact with the cylinder" and nearby structures "get less radiation exposure".
Who is offered vaginal cuff brachytherapy?
It is used mainly after hysterectomy for endometrial cancer when the features of the tumour suggest an intermediate or "high-intermediate" risk of the cancer returning in the vagina. Cancer Research UK says internal radiotherapy may be used for intermediate-risk womb cancer. The American Society for Radiation Oncology (ASTRO) 2023 guideline recommends radiotherapy — "either vaginal brachytherapy or external beam RT" — based on each patient's clinical and pathological risk factors.
Those risk factors are details from your pathology report, such as how deeply the tumour grew into the wall of the uterus and its grade and type — and, increasingly, the tumour's molecular profile. ASTRO notes that molecular data "should be increasingly considered" in these decisions. This is why two people with the "same stage" can receive different advice.
Vaginal brachytherapy can also be given:
- At the end of external beam radiotherapy to the pelvis, as a top-up (Macmillan: "you may have it at the end of your external radiotherapy treatment").
- After hysterectomy for cervical cancer in some situations. For treatment when the uterus is still in place, see our guide to brachytherapy for cervical cancer.
- For people who cannot have surgery, as part of primary treatment — this is a different, longer procedure with applicators in the uterus (Cancer Research UK describes 3 to 6 treatments in that situation).
The vaginal cylinder and a typical session
The American Brachytherapy Society (ABS) guideline on vaginal cuff brachytherapy says the applicator should be chosen according to "patient anatomy, target volume geometry, and physician judgment", and that a properly fitted applicator should conform to the top of the vagina and stay in contact with its lining. In practice, most centres use a smooth cylinder available in several diameters, and choose a size that fits snugly, because the guideline stresses contact with the vaginal lining for a good dose distribution.
A typical high-dose-rate (HDR) session, as described by the American Cancer Society, Macmillan and Cancer Research UK, goes like this:
- Positioning. You lie on your back on the treatment couch in a private treatment room.
- Insertion. A doctor, nurse or radiographer gently inserts the cylinder, using lubricating gel. It is held steady so it does not move during treatment.
- Check. Your centre may take a scan or X-ray to confirm the position and plan the dose, particularly at the first session.
- Treatment. The cylinder is connected by a tube to the afterloader. Staff leave the room but can see and talk to you through a camera and intercom. The source travels into the cylinder, pauses at planned positions and returns. The American Cancer Society says "the radiation is only in for 10 to 20 minutes" and each visit usually takes "less than an hour".
- Home. The cylinder is removed and, in Macmillan's words, "you can go home". No overnight stay is needed for HDR.
Low-dose-rate (LDR) vaginal brachytherapy also exists: the applicator stays in for "up to 4 days" in hospital. The American Cancer Society notes it "isn't commonly used in the United States" and carries a risk of blood clots from lying still. See HDR vs LDR brachytherapy for the general difference.
How many brachytherapy treatments for endometrial cancer?
After hysterectomy, most schedules use about three HDR treatments, although some centres use more. The American Cancer Society says HDR "might be given weekly or even daily for at least 3 doses", and Cancer Research UK describes "up to 3 treatments lasting about 20 minutes each" for intermediate or high-intermediate risk. In the PORTEC-2 trial, the HDR schedule was 21 Gy in three fractions.
What that means for your calendar depends on the spacing. A simple worked example:
| Schedule pattern | Visits | Treatment days | First to last treatment | Radiation time in total (at 10–20 min each) |
|---|---|---|---|---|
| 3 treatments, once a week | 3 | Days 1, 8, 15 | about 2 weeks | about 30–60 minutes |
| 3 treatments, twice a week | 3 | e.g. Mon, Thu, Mon | about 1 week | about 30–60 minutes |
| 3 treatments, daily | 3 | Days 1, 2, 3 | 3 days | about 30–60 minutes |
| Brachytherapy after external beam | set by the combined plan | at the end of pelvic radiotherapy | adds to a multi-week course | depends on the plan |
The ABS guideline tabulates suggested doses for brachytherapy alone and in combination with external beam, and asks centres to report the dose at the vaginal surface and at 0.5 cm depth. You do not need to know the numbers, but asking "how many treatments, how far apart, and over what length of vagina?" will tell you most of what matters.
Is vaginal brachytherapy painful? Are you radioactive afterwards?
Pain and comfort
For most people, vaginal cuff brachytherapy is uncomfortable rather than painful. No general anaesthetic is usually needed after a hysterectomy: Cancer Research UK describes outpatient treatment where the applicator "should not be painful", and the American Cancer Society adds that "if needed, pain medicines can be used". The radiation itself is not felt. If you are anxious, or insertion was difficult after surgery, tell the team — sizes and positioning can be adjusted. Our guide is brachytherapy painful? compares comfort across treatment types.
Radiation safety at home
No source stays in your body. Cancer Research UK states: "You are only radioactive when the treatment machine is switched on", so afterwards you are "safe to be around everyone, including children". You can hug, sleep next to a partner and be around pregnant people and pets as usual. For how this differs from permanent seed implants, see why no radiation stays in your body after HDR treatment.
Side effects and dilators
Side effects of vaginal brachytherapy alone are usually mild and local. Macmillan says that if you are having brachytherapy only, "it is not common to get side effects after treatment", though vaginal changes can follow later.
| When | What can happen | Source |
|---|---|---|
| First weeks | Vaginal irritation, discharge, light bleeding; side effects "tend to happen about 1 to 2 weeks after treatment" | American Cancer Society; Cancer Research UK |
| First weeks | Bladder irritation (burning or passing urine more often), diarrhoea — more typical when external beam is also given | Cancer Research UK; American Cancer Society |
| Months to years | Vaginal dryness — "more common after vaginal brachytherapy than after pelvic radiation therapy" | American Cancer Society |
| Months to years | Scar tissue making the vagina "shorter, narrower and less stretchy" (vaginal stenosis), which can make sex or examinations uncomfortable | Cancer Research UK; American Cancer Society |
| Rare, long term | Bladder or bowel damage (radiation cystitis or proctitis) — more associated with pelvic external beam | American Cancer Society |
Vaginal dilators
Cancer Research UK says that to help prevent narrowing, "your radiographer or nurse will give you vaginal dilators to use regularly after your radiotherapy treatment". The evidence is weaker than many people assume: a 2014 Cochrane review found no randomised trials proving that routine dilation prevents stenosis, although observational studies link frequent dilation with less self-reported narrowing. Lubricants, vaginal moisturisers and, when appropriate, regular sex are often discussed alongside dilators. Ask your nurse when to start, how often, and what to do if it is uncomfortable.
Vaginal brachytherapy vs pelvic external beam: what the trial showed
The main evidence for using brachytherapy alone, rather than pelvic external beam radiotherapy, comes from the Dutch PORTEC-2 randomised trial (The Lancet, 2010). It included 427 patients with stage I or IIA endometrial cancer with high-intermediate risk features.
| PORTEC-2 result | Vaginal brachytherapy | Pelvic external beam |
|---|---|---|
| Treatment given | 21 Gy HDR in 3 fractions (or 30 Gy LDR) | 46 Gy in 23 fractions |
| Vaginal recurrence at 5 years | 1.8% | 1.6% |
| Overall survival at 5 years | 84.8% | 79.6% (no significant difference) |
| Acute grade 1–2 bowel side effects at end of treatment | 12.6% | 53.8% |
The authors concluded that vaginal brachytherapy "should be the adjuvant treatment of choice" for high-intermediate-risk endometrial cancer, because it controlled the vagina as well as external beam with fewer bowel side effects. Pelvic recurrences were slightly more frequent after brachytherapy (not statistically significant), which is one reason higher-risk features may still lead to external beam. For more on the two approaches, see brachytherapy vs external beam radiation.
Questions to ask your team
- Why are you recommending vaginal brachytherapy for me, rather than external beam, observation or chemotherapy?
- Has my tumour had molecular testing, and does it change the recommendation?
- How many treatments, how far apart, and when do they start after surgery?
- Will I need any anaesthetic or painkillers for insertion?
- How long will each visit take, and can someone come with me?
- Which side effects should I report, and who do I call?
- Will I be given dilators, and when should I start using them?
- What follow-up will I have after treatment?
Background on the treatment itself is on our brachytherapy basics page, and a printable list is in our questions to ask before brachytherapy.
FAQ
How many brachytherapy treatments are there for endometrial cancer after hysterectomy?
Usually about three high-dose-rate treatments, although schedules vary. The American Cancer Society says treatment may be given weekly or even daily for at least 3 doses, Cancer Research UK describes up to 3 treatments of about 20 minutes, and the PORTEC-2 trial used 3 fractions.
Is vaginal cuff brachytherapy painful?
It is usually uncomfortable rather than painful and does not normally need a general anaesthetic. The American Cancer Society compares the cylinder to a snug tampon, and Cancer Research UK says the applicator should not be painful. Pain medicine can be used if needed, and the radiation itself is not felt.
Am I radioactive after vaginal brachytherapy?
No. The source is removed at the end of every treatment. Cancer Research UK states that you are only radioactive while the treatment machine is switched on, so afterwards you are safe to be around everyone, including children.
How long does each vaginal brachytherapy session take?
The radiation is usually in place for about 10 to 20 minutes, and the American Cancer Society says each high-dose-rate treatment usually takes less than an hour in total. You go home the same day.
Is vaginal brachytherapy as effective as pelvic external beam radiotherapy?
For high-intermediate-risk endometrial cancer, the PORTEC-2 randomised trial found similar 5-year vaginal recurrence rates (1.8% with vaginal brachytherapy vs 1.6% with external beam) and far fewer acute bowel side effects with brachytherapy. Higher-risk cancers may still need external beam or other treatment.
Sources
- American Cancer Society — Radiation Therapy for Endometrial Cancer (accessed 9 October 2026)
- Cancer Research UK — Internal radiotherapy (brachytherapy) for womb cancer (accessed 9 October 2026)
- Macmillan Cancer Support — Radiotherapy for womb cancer (accessed 9 October 2026)
- National Cancer Institute — Endometrial Cancer Treatment (PDQ®), patient version (accessed 9 October 2026)
- Small W Jr, Beriwal S, et al. American Brachytherapy Society consensus guidelines for adjuvant vaginal cuff brachytherapy after hysterectomy. Brachytherapy. 2012;11(1):58-67 (accessed 9 October 2026)
- Nout RA, et al. Vaginal brachytherapy versus pelvic external beam radiotherapy for patients with endometrial cancer of high-intermediate risk (PORTEC-2). Lancet. 2010;375(9717):816-823 (accessed 9 October 2026)
- Harkenrider MM, et al. Radiation Therapy for Endometrial Cancer: An American Society for Radiation Oncology Clinical Practice Guideline. Pract Radiat Oncol. 2023;13(1):41-65 (accessed 9 October 2026)
- Miles T, Johnson N. Vaginal dilator therapy for women receiving pelvic radiotherapy. Cochrane Database Syst Rev. 2014;(9):CD007291 (accessed 9 October 2026)
Educational content. It does not replace advice from qualified healthcare professionals. Your own treatment team is the right source for decisions about your care. Written by the brachytherapist.com editorial team from the sources listed above.