Adjuvant radiation therapy and/or chemotherapy introduce higher risks of infertility in patients with cancer. Sterility from these therapies may be temporary or permanent. The occurrence of this toxicity is related to a number of factors including the following:
Age at the time of treatment.
Type of therapeutic agent.
Single versus multiple agents.
Length of time since treatment.
When treatment-related or disease-related dysfunction is a possibility, every effort should be made to provide adequate information and education on reproduction and fertility. Conveying such information can be complicated, especially in younger pediatric cancer patients. Children may be too young to comprehend the implications of treatment on fertility. Additionally, in some instances, parents may decide to shelter children from such discussions.
Mistletoe is a semiparasitic plant that grows on several types of common trees such as apple, oak, pine, and elm. Mistletoe extract has been used since ancient times to treat many ailments (see Question 1).
Mistletoe is one of the most widely studied complementary and alternative medicine therapies in people with cancer. In certain European countries, preparations made from European mistletoe are among the most prescribed drugs for patients with cancer (see Question 1).
Existing literature suggests that only about half of men and women of child-bearing age receive the information they need from their health care providers about cancer-related infertility at the time of diagnosis and treatment planning. This lack of information is one of the most common reasons men give for failing to bank sperm. To address this issue, a computerized interactive educational tool for patients, families, and physicians called Banking on Fatherhood after Cancer is under development and will be viewable on CD-ROM or over the Internet.
With regard to chemotherapy, the extent of damage to a patient's fertility depends on the agent administered, the doses received, and the patient's age at the time of treatment. Age is an important factor, and the possibility of gonadal recovery improves with the length of time off chemotherapy. The germinal epithelium of the adult testis is more susceptible to damage than that of the prepubertal testis. The evidence to date (largely from adjuvant studies) suggests that patients older than 35 to 40 years are most susceptible to the ovarian effects of chemotherapy. The ovaries of younger women can tolerate greater doses. Predicting the outcome for any individual patient is difficult, as the course of ovarian functioning following chemotherapy is variable. Relative risk of ovarian failure and testicular damage from cytotoxic agents has been studied, and the alkylating agents have subsequently been shown to be damaging to fertility. The following agents have been shown to be gonadotoxic: [3,5,6,7,8]