Testicular cancer is the most common solid tumour in men of reproductive age and as the 10 year survival rate exceeds 97%, long-term complications need to be considered. Primary hypogonadism, defined as low total testosterone levels with elevated luteinising hormone (LH) occurs in up to 20% of testicular cancer survivors and has been associated with increased risk of metabolic syndrome. In addition to hypogonadism, impaired fertility may occur, often related to treatment intensity (particularly with chemotherapy). Independent of treatment, underlying risk factors for testicular germ cell tumours such as cryptorchidism may also be risk factors for hypogonadism or infertility.
Delineating symptoms attributable to hypogonadism are challenging, as many symptoms such as fatigue, decreased libido and mood disturbance are non‐specific. Untreated hypogonadism may contribute to long‐term osteoporosis and metabolic syndrome which predisposes to cardiovascular disease.
A decision to initiate testosterone replacement, which is often given lifelong, should be individualised. Benefits and potential risks should be carefully weighed and there is insufficient evidence to show that testosterone replacement is of benefit on metabolic syndrome. Studies in older men without cancer with mild hypogonadism have suggested that testosterone replacement may be associated with increased coronary atherosclerosis. Furthermore, as testosterone is a contraceptive, it should not be initiated in men seeking fertility without discussion with a fertility specialist. Nonetheless, men who have biochemical hypogonadism and clear symptoms should be considered for a trial of testosterone therapy and treatment should be ceased if no demonstrable benefit is achieved.