Genetics of erectile dysfunction.

PURPOSE: Erectile dysfunction affects 50% of men older than 40 years. Recently more attempts have been made to identify genetic predictors of this disease. We reviewed animal and human data on genes related to the development and increased risk of erectile dysfunction. MATERIALS AND METHODS: A literature search was performed using the PubMed® database. Articles addressing genes involved in erectile dysfunction were evaluated. RESULTS: The majority of studies used a candidate gene approach to investigate genetic polymorphisms of known pathways mediating erection/detumescence. Studies in human and animal models are available. Human studies often compared the frequency of a specifically predetermined genetic polymorphism in men with erectile dysfunction to that in matched controls in whom few genes were persistently replicated. Several gene expression profiling studies are available that targeted specific erectile dysfunction models. Currently, there are few human genome wide association studies of erectile dysfunction. CONCLUSIONS: Studies investigating the genetics of erectile dysfunction are mostly derived from animal models and candidate gene approaches. Candidate gene studies omit the greater portion of the genome, a problem that can be solved using a genome wide association study approach. The lack of persistently replicated results of candidate gene studies may be related to different patient ethnic backgrounds, variations in erectile dysfunction etiology and small sample sizes. Using strict inclusion/exclusion criteria for erectile dysfunction etiology and ethnicity in human studies may lead to improved understanding of the genetics of erectile dysfunction in specific populations.

Predictors of sperm recovery after cryopreservation in testicular cancer.

Our objective was to identify predictors of improved postthaw semen quality in men with testicular cancer banking sperm for fertility preservation. We reviewed 173 individual semen samples provided by 67 men with testicular germ cell tumor (TGCT) who cryopreserved sperm before gonadotoxic treatment between 1994 and 2010 at our tertiary university medical center. Our main outcomes measures were independent predictors for the greater postthaw total motile count (TMC) in men with TGCT. Men with NSGCT were more likely to be younger (P < 0.01) and had high cancer stage (II or III, P < 0.01) compared with men with seminoma. In our multiple regression model, NSGCT histology, use of density gradient purification, and fresh TMC > median fresh TMC each had increased odds of a postthaw TMC greater than median postthaw TMC. Interestingly, age, advanced cancer stage (II or III), rapid freezing protocol, and motility enhancer did not show increased odds of improved postthaw TMC in our models. In conclusion, men with TGCT or poor fresh TMC should consider preserving additional vials (at least 15 vials) before oncologic treatment. Density gradient purification should be routinely used to optimize postthaw TMC in men with TGCT. Larger, randomized studies evaluating cancer stage and various cryopreservation techniques are needed to assist in counseling men with TGCT regarding fertility preservation and optimizing cryosurvival.

Raw and test-thaw semen parameters after cryopreservation among men with newly diagnosed cancer.

OBJECTIVE: To characterize sperm parameters from thawed semen samples of men with different cancers who cryopreserved semen before oncologic therapy. DESIGN: Retrospective cohort study. SETTING: Tertiary academic medical center. PATIENT(S): 1,010 semen samples collected between 1994 to 2010. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Mean total motile count (TMC), change in percentage motility and percentage survival (100 * [postthaw % motility/raw % motility]) for each cancer compared with data from samples of men without cancer (the "procreative management" group), and proportion of postthaw samples with TMC >5 × 10(6). RESULT(S): The procreative management group had the best raw and postthaw semen quality. The best raw and postthaw semen quality for cancer patients occurred in those with prostate cancer (TMC of 155.1 and 53.2 × 10(6), respectively) and the worst in those with leukemias. Lymphoid leukemias demonstrated the worst raw TMC (26.8 × 10(6)), but myeloid leukemias displayed the worst postthaw TMC (6.9 × 10(6)). The testicular cancer group was the only group with a statistically significantly lower chance of having TMC >5 × 10(6). CONCLUSION(S): Men with testicular cancer were most commonly referred for sperm cryopreservation and were the only group that was statistically significantly less likely to have TMC >5 × 10(6) on postthaw semen analysis. The most severe reduction in TMC was seen in the myeloid leukemia group, suggesting that these patients along with men with testis cancer and those with lymphoid leukemia should be counseled to provide increased numbers of specimens for fertility preservation.

Surgical techniques for the management of male infertility.

Evaluation and surgical treatment of male infertility has evolved and expanded, now leading to more precise diagnoses and tailored treatments with diminished morbidity and greater success. Surgeries for male infertility are divided into four major categories: (i) diagnostic surgery; (ii) surgery to improve sperm production; (iii) surgery to improve sperm delivery; and (iv) surgery to retrieve sperm for use with in vitro fertilization and intracytoplasmic sperm injection (IVF-ICSI). While today we are more successful than ever in treating male infertility, pregnancy is still not always achieved likely due to factors that remain poorly understood. Clinicians treating infertility should advocate for couple-based therapy, and require that both partners have a thorough evaluation and an informed discussion before undergoing specific surgical therapies.