Preservation of male fertility in patients undergoing pelvic irradiation

Abstract

As the number of cancer survivors increases, so does the demand for preserving male fertility after radiation. It is important for healthcare providers to understand the pathophysiology of radiation-induced testicular injury, the techniques of fertility preservation both before and during radiation, and their role in counseling patients on the risks to their fertility and the means of mitigating these risks. Impaired spermatogenesis is a known testicular toxicity of radiation in both the acute and the late settings, as rapidly dividing spermatogonial germ cells are exquisitely sensitive to irradiation. The threshold for spermatogonial injury and subsequent impairment in spermatogenesis is ~ 0.1 Gy and the severity of gonadal injury is highly dose-dependent. Total doses < 4 Gy may allow for recovery of spermatogenesis and fertility potential, but with larger doses, recovery may be protracted or impossible. All patients undergoing gonadotoxic radiation therapy should be counseled on the possibility of future infertility, offered the opportunity for semen cryopreservation, and offered referral to a fertility specialist. In addition to this, every effort should be made to shield the testes (if not expected to contain tumor) during therapy.

Keywords: electroejaculation; gonadotoxic radiation; male fertility; penile vibrostimulation; semen cryopreservation.

Figure 1

Sperm retrieval techniques. A. Percutaneous epididymal sperm aspiration (PESA). The needle is placed into the head of the epididymis as close to the efferent ducts as possible. B. Microsurgical epididymal sperm aspiration (MESA). This is the most precise and successful way to retrieve epididymal sperm. Under a general anesthetic, the testicle is delivered from the scrotum and the head of the epididymis is reflected back from the testicle with a finger exposing the efferent ducts draining from the testicle to the epididymis. Here, a single dilated efferent duct is punctured and sperm is aspirated

Figure 2

Microdissection testicular sperm extraction (microTESE). A. Under a general anesthetic, the testicle is delivered through a scrotal incision. An equatorial incision is made in the tunica albuginea; B. The testicle is bi-valved exposing the seminiferous tubules; C. The seminiferous tubules are carefully searched under an operating microscope until a dilated tubule is identified. These dilated tubules are more likely to contain sperm and should be harvested. The tissue is then placed in sperm transport media, minced then examined under a microscope by the embryology team for the presence of sperm; D. Once the microTESE is complete, hemostasis is achieved with bipolar cautery and the tunica albuginea is closed

Figure 3

Clamshell, designed to reduce scatter radiation to the testes. It consists of a spherical lead cup with a wall thickness of 0.5 inches (1.27 cm). The open sector allows for comfortable attachment to the patient and the adjustable stand allows for increased patient comfort