Cancers can affect any part of the body. They may affect the reproductive system in males as in testicular cancers or cancers of the prostrate and may by itself be responsible for causing infertility.

Cancer therapy involves either surgical removal or radiotherapy or chemotherapy. Most malignancies are treated by a combination of the three methods for optimum results. Both chemotherapy and radiotherapy are known to induce infertility in males. The infertility is likely to be temporary in most cases except when large doses (>600 rads) of radiation or chemotherapy is used.

How does chemotherapy affect male fertility?

Chemotherapeutic drugs like bleomycin, cyclophosphamide, cisplatin etc act against actively dividing cells which is a characteristic of cancer cells. This property of rapid and quick division is also seen in the germ cells of the male reproductive system due to which they are destroyed post chemotherapy. The germinal epithelium lining the seminiferous tubules are the most affected cells leading to decrease in sperm counts (oligospermia) or sometimes absence of sperms (azoospermia).

The reduction in sperm counts begins approximately three weeks after chemotherapy and continues to fall for upto 3 to 4 months. Cytotoxic drugs have very little effects on the Leydig cells and hence do not affect the levels of testosterone and secondary sexual characteristics of affected males. Some chemotherapeutic drugs are toxic to the nerves and male lead to erectile dysfunction in males.

Return of male fertility post chemotherapy:

The return of fertility is likely to be from one to three years after the completion of chemotherapy. There are many factors that are responsible for the return of fertility in males who have undergone chemotherapy.

Age: As age increases, it is well known that the fertility decreases, hence in individuals more than 35 years of age return of fertility may take longer time.
Type of Cytotoxic drugs: Among the Cytotoxic drugs, alkaloids have demonstrated maximum toxicity to the germinal epithelium.
Duration of therapy: Longer the duration of therapy longer the duration of infertility.
Site of involvement: Cancers of the reproductive systems are likely to be more affected than those suffering from other cancers.
Drugs for return of fertility: Some experimental drugs have been tried to maintain fertility in males despite chemotherapy. One such trial was carried out with Taxol and an experimental drug AS101. AS101 has demonstrated protection from hair loss and bone marrow damage in some studies after chemotherapy. Animal experiments with mice showed that while the Taxol alone caused significant reduction in the testicular weight, a combination of Taxol and AS101 showed only minimal reduction in the testicular weight of the treated mice.
Sperm bank: One option of conserving the sperms is the storage of semen prior to chemotherapy. This option is viable especially in individuals where the doctor may feel that infertility is likely to be permanent or may not return for a prolonged time.
Assisted reproduction: Though the return of fertility is seen in about 35% to 75% of males after chemotherapy, it is likely that the couple will require assistance for reproduction. One such method called intrauterine insemination (IUI) has helped many couples conceive in the past.