The “contraceptive coil raises hope of delaying womb cancer”, reported the BBC. A “promising early trial” has found that the coil, also known as the intrauterine device or IUD, can deliver hormones to the lining of the womb (endometrium), which can halt or reverse cancer growth, explained the website.
This study did not involve the conventional coil (IUD) as this does not release hormones. This was a study of the levonorgestrel-releasing intrauterine system (LNG-IUS or Mirena coil). It was used alongside monthly injections of a hormone called GnRH (gonadotropin-releasing hormone) for the treatment of women in a specialist cancer centre. Twenty of the women had abnormal overgrowth of the womb lining and 14 had early-stage cancer of the womb lining (endometrial cancer). The combined coil and hormone injection was shown to reduce their risk of the disease progressing or recurring.
This is important early research of a potential new treatment combination. Women should not interpret the news reports as meaning that using the coil (either conventional or Mirena) will reduce their risk of developing endometrial cancer, or that it can be used as a treatment for cancer. The Mirena coil is currently licensed in the UK as a long-term contraceptive, particularly in women who have heavy periods.
Where did the story come from?
The study was carried out by researchers from the European Institute of Oncology in Milan and the Centro Integral Oncologico Clara Campal (CIOCC) in Madrid. No sources of external funding were reported. The study was published in the peer-reviewed medical journal Annals of Oncology.
The headlines in both The Daily Telegraph and BBC News are likely to confuse the reader into thinking that the conventional coil (IUD) was studied. However, the research looked at the commonly used Mirena coil in combination with GnRH hormone treatment. This is not currently a conventional treatment method, and it was being trialled here in a very specific population of women who wanted to avoid surgical treatment of their cancer or pre-cancer.
What kind of research was this?
This case series reported the experiences of gynaecologists who used the Mirena coil plus gonadotropin-releasing hormone (GnRH) to treat women aged under 40. These women had abnormal overgrowth (hyperplasia) of the lining of the womb or early-stage endometrial cancer. The sample of women all wished to preserve their fertility, which ruled out conventional treatments for these conditions, including hysterectomy, radiotherapy or chemotherapy.
What did the research involve?
The study involved 34 women, including 20 women with endometrial hyperplasia and 14 women with early-stage cancer. The women had been referred to the European Institute of Oncology in Milan between January 1996 and June 2009 to investigate non-surgical treatment of their condition. The average age of the women was 34 years. All women underwent full assessment, examination and staging of their condition before treatment. The treatment involved insertion of the Mirena coil for one year, as well as monthly GnRH injections for six months.
Pelvic ultrasound examination and a biopsy of the lining of the womb were carried out at six months and one year to assess the results. On average, the women were followed up for about two-and-half years, though the highest length of follow-up was over eight years. The researchers determined the response to treatment according to whether there was any difference from pre-treatment measurements. The results were classed as:
- complete response if the latest biopsy showed normal womb lining
- stable disease if the latest biopsy had the same appearance under the microscope as the first sample
- progressed disease if early cancer appeared in those who had initial hyperplasia only
- recurrence if new hyperplasia or early cancer appeared in the latest biopsy compared with a previously negative biopsy
Complete response at one year was the researchers’ primary outcome of interest. Adverse effects, treatment failure rates, pregnancy rates, recurrence and survival were all secondary outcomes.
What were the basic results?
The complete response rate to treatment was 95% in patients with hyperplasia (19 out of 20 women) and 57.1% in women with early-stage cancer (8 out of 14 women) at the first six-month follow-up. Disease progression was observed in 1 out of the 20 women with hyperplasia and 4 out of 14 women with early-stage cancer. Two patients with early-stage cancer remained stable.
Recurrence occurred in 4 out of 20 women with hyperplasia and 2 out of 14 women with early-stage cancer. The average time to recurrence was 36 months (range between 16 and 62 months). These women were all treated appropriately in line with current guidance.
All women, including those who responded and those who had progression or recurrence and then received conventional treatment, were alive without evidence of disease at the last follow-up (average of 29 months). Nine women achieved 11 spontaneous pregnancies.
How did the researchers interpret the results?
The researchers concluded that the combined treatment showed effectiveness in “a substantial proportion” of patients with endometrial hyperplasia and early-stage endometrial cancer. They say that close follow-up during and after treatment is crucial.
This study reported the experiences of treating 34 young women with early-stage endometrial cancer or pre-cancerous endometrial hyperplasia. The women wished to preserve their fertility, which ruled out conventional surgical treatments. They were treated with a combination of the Mirena coil, which was inserted for one year, and gonadotropin-releasing hormone (GnRH) injections for six months.
The results of this small sample of women were generally positive, with high complete response rates. Those who did not respond to treatment or who had recurrent disease were treated in line with current recommendations, and all the women were alive at the final follow-up. The results are encouraging and will require replication in larger population samples.
These are early results for a combined treatment, used in a specialist hospital setting, for women with a specific type of disease. Women should not misinterpret from the news reports that the coil (either the conventional [IUD] or Mirena coil) can reduce their risk of developing endometrial cancer or can be used as a treatment for cancer. The Mirena coil is currently licensed in the UK as a long-term contraceptive, particularly in women who have heavy periods. This study investigated insertion of the Mirena coil for one year along with monthly GnRH injections for six months.
Analysis by Bazian
Edited by NHS Website
Links to the headlines
BBC News, 28 September 2010
The Daily Telegraph, 28 September 2010
Links to the science
Annals of Oncology, September 28 2010 (published online)