Onkológia 3/2018
Gravidita po onkologickej liečbe
Pregnancy after cancer treatment Over the past four decades, there has been a rising trend of delaying childbearing. Given that cancer incidence increases with age, on one hand there are more women diagnosed during pregnancy and on the other hand there is an increasing number of women desiring pregnancy following cancer diagnosis. In general, cancer survivors have reduced rates of pregnancy compared with general population. Women with breast cancer have the lowest chance of pregnancy , which is nearly 70 % lower compared to general population. This is believed to be secondary to gonadotoxic chemotherapy, prolonged use of tamoxifen in patients with HR+ breast cancer and also general misconception that pregnancy could stimulate cancer recurrence. Apart from breast cancer, no reservations were made regarding the safety of pregnancy following cancer. Neonatal outcomes in women with prior history of cancer are comparable with general population. Several studies and meta-analysis having shown that pregnancy after breast cancer is safe, if not associated with better outcome. There is no particular optimal time-point of becoming pregnant following cancer diagnosis. In breast cancer patient, it is reasonable to postpone pregnancy for 2 years following diagnosis to allow resumption of adequate ovarian function and to overcome the frame associated with relatively high risk of reccurence. Age is the most important determinant of chemotherapy or radiotherapy-induced ovarian dysfunction. Other influencing factors are the use of alkylating agents, total dose of cytostatics, fields and dosage of pelvic radiotherapy. The concomitant use of gonadotropin-releasing hormone agonists (GnRHa) with chemotherapy in meta-analysis of 12 randomized trials in patients with breast cancer showed doubling of pregnancy rate without compromising cancer endpoints, but it does not work for lymphoma patients. Embryo and oocyte cryopreservation is the main method to preserve female fertility, while freezing ovarian tissue, is still experimental.
Keywords: pregnancy, cancer treatment, long-term toxicity, gonadotropin-releasing hormone agonists, premature ovarian insuficience, amenorea, fertility, breast cancer, lymphoma, cryopreservation
