Medical updates
New figures reveal increased survival among cancer patients
At last good news for cancer sufferers
A report published jointly by the ICRF and the Office for National Statistics in June stated that the proportion of cancer patients surviving for five years after diagnosis (with the 15 most common cancers) improved from 25% in 1981 to 30% in1989.
Commenting on the figures, Dr Gillian Reeves (ICRF Unit and researcher on the project) said: "About 200,000 people in England and Wales were diagnosed with cancer in 1989 and 60,000 survived for at least five years – about 10,000 more than would have survived in 198. Simply diagnosing cancer earlier in its development can by itself create the appearance of increased survival. However, it looks as if the cancers showing increased survival are those where we know that earlier detection or better treatment can improve prognosis."
Dr Paul Nurse, Director-General of ICRF added: "These figures identify positive trends with some of the more common cancers which probably reflect better detection and treatment, and improvements in the way cancer services are delivered. With continued research into cancer we hope to see further improvements in the future."
Professor Karol Sikora, clinical consultant to the ICRF said: "These figures are very encouraging indeed and represent a huge effort by nurses, doctors and other staff in the NHS. Cancer treatment will get better as we go into the new millennium, but we must ensure that every cancer patient gets the best possible care."
Dr Mike Quinn, Director of the National Cancer Registration Bureau at ONS said "These results are based on over 370,000 people diagnosed with cancer in 1981 and 1989 and represent the most reliable national estimates of cancer survival available."
Although the report covers 15 of the most common cancers (including ovarian cancer) it is still very encouraging indeed to see that the survival rate for ovarian cancer sufferers has increased by 5.3%. It is hoped that this rate will continue to rise following the parliamentary briefing that took place in February. As mentioned in the summer: "The parliamentary briefing brought together top ovarian cancer consultants and MPs who were urged to lobby ministers to review the latest evidence on the best treatment for ovarian cancer. 120 MPs signed an early-day motion calling for ‘equitable care for all women with ovarian cancer’, and national and local action to give women equal access to optimal treatment around the country is expected to continue. This House of Commons briefing served as a catalyst for the development of a new all-party group on cancer, which is charged with looking at the wide range of issues relating to cancer services and treatments. In the first session of the group, consistent and optimal treatment standards for ovarian cancer were voiced. Ovacome was invited to attend all these sessions, and will continue to be."
Another factor that will hopefully encourage better survival rates for ovarian cancer is the recent result from a European/Canadian clinical trial of Taxol. This new data has shown that Taxol offers a worthwhile survival advantage when used as first-line treatment for advanced disease. A Medical Consensus Group set up in the UK reviewed the available data and unanimously agreed that, given the weight of evidence, a fundamental change in the treatment of ovarian cancer is in order and that Taxol should become the new "gold standard" for the majority of patients.
But, as the graph above shows, we are still falling behind the USA (and other European countries), owing to many factors. In an article that appeared in The Sun in June, Professor Gordon McVie stated that Britain has not invested enough money in specialist doctors, and treatment varies from region to region. For example in this country a radiotherapist would have to treat up to 2,000 patients at any one time, whereas one in the US would deal with only one-third of that amount. Also, different health authorities may fund certain types of treatment while others may not. Different hospitals within the same health authority may even offer different treatments depending on financial priorities or whether the hospital employs a cancer specialist. I am sure that following the development of the All Party Working Group on Cancer (as mentioned above) the situation will continue to improve.
Fertility Issues for Women with Ovarian Cancer:
Ovarian Tissue Biopsy and Cryopreservation
As cancer treatments become more successful, the research is now shifting not only to focus on treatment for actual survival, but also to address improving the choices available to long-term survivors‘ overall quality of life. Previously, I covered the treatments commonly used in ovarian cancer which can affect fertility, sometimes permanently. Now I focus on one such research project which aims to offer some degree of hope to women who experience a potential or actual loss of fertility induced by treatment.
Ovarian tissue biopsy followed by cryopreservation (freezing), although still in the research stage, offers a degree of hope and maybe a choice for a woman with ovarian cancer who is keen to preserve all potential fertility options. However, it is important to understand that this new and exciting technique offers no guarantee of a successful outcome in humans. It may be argued that this research study may offer false hope, and this is an important consideration, and one which each individual has to make. For another individual, that potential hope may be extremely important.
For some women, potential or actual loss of fertility can be as much of a shock and as painful to accept as the cancer diagnosis itself. Acknowledging the reality of this situation, and exploring all the alternative options, and the known benefits, advantages and actual or potential risks of each, is the first step towards dealing with the loss.
What are the aims of this research project?
The aim of ovarian tissue biopsy followed by cryopreservation is to develop the technique to the stage where it offers an alternative assisted fertility choice to women with treatment-induced infertility. As yet, however, it has not been demonstrated whether this procedure will be safe in women with ovarian cancer.
It involves removing a small piece of the outer cortex of ovarian tissue (approximately half the size of a thumbnail) before cancer treatment starts, and carefully freezing it. In this way, it may be possible to save some of the immature oocytes (eggs), before they are potentially damaged by the treatment. This technique is new and untried in humans and may not reach a satisfactory conclusion. The hope however remains, and research continues with the aim of providing ovarian tissue that is safe to use. The saved ovarian tissue could be thawed and cultured in the lab and the immature eggs grown to a state of maturity. They could then be fertilised and either replaced into the woman’s womb or used for surrogacy.
So far, technology is available to freeze and store the ovarian tissue at a suitable temperature for the eggs to survive. However, there is no guarantee that the eggs will survive the thawing process, or that the tissue will then be safe to use. The research has not yet advanced to the stage where the woman’s egg can be stimulated to a stage of maturity where it can be fertilised with the sperm. This experimental technique has been tried successfully in animals and normal offspring have been born as a result. As yet, no human pregnancies have resulted from this research. In animals, ovarian tissue has been thawed and replaced, functioning normally, but it is too early to know if the technique will be possible or safe in women with ovarian cancer.
Criteria for ovarian tissue cryopreservation
As this is research, the woman needs firstly to understand that she is agreeing to be involved in an experimental technique, and is consenting to this independently of any other ovarian cancer treatment. Participation is entirely voluntary. This procedure will not effect the woman’s cancer diagnosis, prognosis or the effects of cancer treatment.
The woman should have the opportunity to discuss the implications of the storage of ovarian tissue with the oncology team treating her, the fertility team involved in the project and an independent counsellor if she chooses. She is also free to withdraw from the study at any time, and this will not jeopardise the course of her cancer treatment. Her involvement and any data from the study remain strictly confidential; only researchers have access.
Most centres offering women this opportunity are not including anyone over the age of 35. However, this may change if and when there are developments and progress, which could take from five to 10 years. As with all potential new developments in the field of assisted conception, these remarkable possibilities stimulate wide-ranging discussion as to the ethical and social dilemmas and safety of new techniques.
Consenting to the procedure
If a woman is consenting as part of cancer treatment to undergo a laparotomy (major abdominal incision) or laparoscopy, she may be able to consent to have the piece of ovarian tissue taken at the same time. Taking ovarian tissue during surgery is simple and quick. However, as with all operations there are potential minor risks from the general anaesthetic, infection and, very rarely, damage to other pelvic organs and haemorrhage.
Although laparoscopy is a minor and safe procedure, occasionally it is not technically possible to obtain the ovarian tissue biopsy through a small incision. Therefore, the woman usually needs to consent to a possible laparotomy in case this is necessitated during surgery. This, however rare, is an important consideration, especially if the recovery period is longer than originally anticipated and chemotherapy delayed.
Potential alterations to body image due to surgical scars (however small) also need to be considered, especially in women who would otherwise be undergoing chemotherapy alone, and the surgical procedure is being carried out as part of research which offers no guarantee of success.
If the cancer treatment plan involves chemotherapy before or instead of surgery, then laparoscopy to remove the piece of ovarian tissue will be consented to in addition to the treatment. This will involve assessment by a gynaecologist and an anaesthetist, to establish if the woman is medically fit for a general anaesthetic and surgery. When chemotherapy is the only cancer treatment, an additional surgical procedure may delay the start, and needs to be considered carefully with the medical team.
Some but not all centres offering the treatment request that women are screened for hepatitis B and C and HIV before this procedure, because freezing facilities do not allow tissue to be stored separately. HIV testing stimulates wide-ranging discussion as to the ethical and social dilemmas, and women should be carefully counselled before consenting to additional tests.
Only a few centres offer cryo-preservation (see below). However, if the hospital where the woman is being treated does not have the facility, they may have an arrangement with another centre to preserve and store the tissue. As this is research, there is usually no additional cost incurred in the preservation and storage at present.
Once the ovarian tissue is removed, it is stored in a suitable medium, and transported by courier to the embryologist trained to preserve and freeze it for storage. The woman is requested to indicate on the consent form whether, in the event of her death or if she no longer requires the ovarian tissue, it should be disposed of or made available for research purposes.
Are remaining ovarian function and potential fertility options affected?
This procedure is not thought to adversely affect any potential chance of the ovaries producing eggs again after the cancer treatment has finished. The tissue taken is the size of half a thumbnail, less than 5% of the total number of eggs in the ovaries, and is not thought to effect any remaining ovarian function. However, in most women where this is being considered, the ovaries will be removed during the surgery because of an ovarian cancer diagnosis, or the proceeding chemotherapy treatment may effect any remaining function. Ovarian biopsy does not effect the woman’s ability to conceive using ovum donation (if her uterus remains).
The hope remains, as the research continues into ovarian tissue cryopreservation, that one day this will be a real fertility breakthrough and offer a choice to women which is as yet unavailable.
Karen Summerville
Nurse Specialist in Gynaecological Oncology and Associated Women’s Health Care
CENTRES KNOWN TO OFFER OVARIAN CRYOPRESERVATION
Bourne Hall Assisted Conception Unit (Cambridge)
The Hammersmith Hospital Assisted Conception Unit (London)
Leeds General Infirmary Assisted Conception Unit (Leeds)
St Batholomew’s Hospital Assisted Conception Unit (London)
University College Hospital Assisted Conception Unit (London)
Please write to Ovacome if you know of any additional centres offering ovarian cryopreservation.
