Fertility And Cancer
Propagation of the species and the urge to have children is one of the driving forces of evolution itself. In countries such as ours,there is an immense cultural pressure as well. Many young patients diagnosed with cancer are thus placed in a dilemma regarding their fertility and vital decisions are all too often based on emotion rather than rationality. Fertility means the ability to produce children.The term does not reflect upon the ability to have normal sexual relations. Cancer in people of childbearing age affects fertility in two ways. One is, when it actually affects the sexual organs; for example cancer of the ovary,uterus, cervix in women or of the testes and penis in men. The other is, when certain treatments given to cure cancer damage the function of the reproductive organs.
When cancer of the testis occurs, typically the affected testis is removed. The other testis is usually sufficient to make enough sperm, and fertility is preserved in more than 80 per cent of men. Sometimes, chemotherapy is given afterwards to increase the chances of cure from the cancer. Chemo damages all dividing cells including sperm producing cells and may cause permanent infertility. With modern chemo regimens, however, 40 to 90 per cent of men may still be able to father children successfully, typically beyond two years of treatment.
A major problem for many men is weighing the possibility of losing a chance at treatment of a very highly curable cancer. A way out is to carefully test for sperm adequacy prior to treatment and consider sperm banking. Sperm is collected prior to any treatment and stored in a freezer, to be used at a future date by either artificially inseminating the female partner or by taking her egg and doing an in vitro fertilisation with the stored sperm (test tube baby). The success rates are between 14 to 70 per cent depending on the final viable sperm count, technique used, the woman’s age and other factors.
Cancers affecting the ovary, uterus or cervix are typically treated first by removing these organs surgically. In young women desiring to preserve their chances of fertility, fertility-sparing surgery may be done in certain cases. An attempt is made to preserve at least one ovary and the uterus. Eventually, successful pregnancies in 60 to 80 per cent casesare seen. In cancers of the cervix, special procedures called trachelectomy or conebiopsy may be considered, with successful pregnancies reported in 40 to 60 per cent cases. These are special techniques that are still evolving and need to be performed by appropriately trained gynaecologists or surgical oncologists in highly specialised centres only. However, it is very important to realise that sometimes cure of the cancer may potentially be compromised by such ‘non-standard’ procedures. There may also be increased risk of loss of the pregnancy, premature delivery, low-birth weight of the baby and so forth.
For proper treatment of many cancers, either chemotherapy or radiation (affecting the ovaries) may be required. Many modern chemo regimens do not affect fertility significantly (0-10 per cent risk), but some regimens do. If this is a serious concern, the most common successful technique used to preserve fertility is to perform embryo cryopreservation prior to any cancer therapy. The patient’s ovaries are stimulated by a brief course of hormones, the released eggs are collected and then fertilised in a test tube by sperm obtained from her male partner (or an unknown donor). The embryo thus created is cryopreserved in a freezer for implantation into her womb (or of a surrogate mother) at a future date after cancer therapy is complete. Several such embryos may also be prepared at the same time and preserved. The successful pregnancy rate is 20 to 40 per cent per embryo transfer to the uterus. This technique is commonly available and is performed often in our country as well. Apart from costs, there is the risk that cancer treatment may be delayed due to the egg collection procedure or that the hormones given for egg release may affect the patient adversely. An existing male partner (or an unknown donor, if acceptable) is needed, making this a difficult option for unmarried girls. Other techniques are being tried such as oocyte cryopreservation (preserving the female egg as such), ovarian tissue cryopreservation (preserving slices of the normal ovary with eggs) or ovariostasis (injecting certain hormonal medicines to protect ovarian function from chemotherapy). So far these have been technically difficult to do, expensive, unsuccessful or all of the above. For patients receiving radiation to the pelvis, oophoropexy or ovary transposition is a technique where the ovary is surgically moved to another site in the abdomen where radiation does not affect it. 15 to 80 per cent successful pregnancy rates are reported but it is difficult to perform, fraught with risks and it is doubtful whether it is needed at all. All in all, there are reasonable options for cancer patients wishing to preserve their fertility. Every patient of child-bearing age needs to have a thorough discussion with their medical team, involving their families and requesting a referral to a specialised centre or a reputable fertility clinic if necessary. The desire to have a child must be carefully balanced against the possibility of losing the chance of cure, based on the ground realities.