Quantitative pathologic changes in the human testis after vasectomy. A controlled study

To determine whether there are any deleterious changes in the human testis after vasectomy, we obtained testicular biopsy specimens from 31 healthy men undergoing vasectomy reversal and from 21 healthy, fertile volunteers. Morphometric analyses of these specimens revealed a 100 per cent increase in the thickness of the seminiferous tubular walls (P less than 0.001), a 50 per cent increase in the mean cross-sectional tubular area (P less than 0.001), and a significant reduction in the mean number of Sertoli cells (P less than 0.01) and spermatids (P less than 0.01) per tubular cross section in the post-vasectomy group, as compared with the control group. Focal interstitial fibrosis was observed in 23 per cent of the specimens from the post-vasectomy group and in none from the control group. There was a significant correlation (P less than 0.01) between interstitial fibrosis and infertility in patients who underwent a surgically successful vasectomy reversal (sperm in the ejaculate). None of the other measured characteristics correlated with infertility after vasectomy reversal. We conclude that significant morphologic changes occur in the human testis after vasectomy. The presence of focal interstitial fibrosis was associated with a high incidence of infertility in this series.

Safety and effectiveness of vasectomy

OBJECTIVE

To recommend further research on vasectomy based on a systematic review of the effectiveness and safety of vasectomy.

DESIGN

A systematic MEDLINE review of the literature on the safety and effectiveness of vasectomy between 1964 and 1998.

MAIN OUTCOME MEASURE(S)

Early failure rates are <1%; however, effectiveness and complications vary with experience of surgeons and surgical technique. Early complications, including hematoma, infection, sperm granulomas, epididymitis-orchitis, and congestive epididymitis, occur in 1%-6% of men undergoing vasectomy. Incidence of epididymal pain is poorly documented. Animal and human data indicate that vasectomy does not increase atherosclerosis and that increases in circulating immune complexes after vasectomy are transient in men with vasectomies. The weight of the evidence regarding prostate and testicular cancer suggests that men with vasectomy are not at increased risk of these cancers.

CONCLUSION(S)

Publications to date continue to support the conclusion that vasectomy is a highly effective form of contraception. Future studies should include evaluations of the long-term effectiveness of vasectomy, evaluating criteria for postvasectomy discontinuation of alternative contraception for use in settings where semen analysis is not practical, and characterizing complications including chronic epididymal pain syndrome.

Hormonal risk factors in testicular cancer. A case-control study

The authors interviewed 273 northern California testicular cancer cases aged 40 and under diagnosed between 1976 and 1981, their mothers, and matched peer controls and their mothers on prenatal hormone exposure and other variables. Included was a population-based substudy (1979-1981) of all interviewable cases reported to the San Francisco Bay Area Surveillance, Epidemiology, and End Results registry. They found odds ratios (OR) of from 8.3 (sons' report) to 4.5 (mothers' report) associated with cryptorchidism, but found no association with mothers' hormone exposure or diethylstilbestrol exposure in pregnancy. They also found a significant association with lower age at puberty (OR = 2.0); a marginally significant association with mothers' breast cancer (OR = 2.9, p = 0.054); and a significant protective effect of reported mononucleosis (OR = 0.6). These associations remained strong in the population-based substudy. When cases were divided by histology, strong and specific associations of earlier puberty (OR = 2.3) and mothers' breast cancer (OR = 4.4) with nonseminomatous cancer, and of reported mononucleosis (OR = 0.3) with seminomatous cancer, were found. These observations suggest that 1) prenatal exogenous hormone exposure does not account for a significant fraction of testicular cancer, 2) a cluster of "breast-cancer-like" risk factors are associated with nonseminomas, and 3) there is some genetic risk of nonseminomas.

Vasectomy increases the severity of diet-induced atherosclerosis in Macaca fascicularis

Diet-induced atherosclerosis developed more extensively in vasectomized cynomolgus monkeys (Macaca fascicularis) than in sham-vasectomized control monkeys fed the same diet. The effect was most pronounced in the abdominal aortas, carotid arteries, distal segments of the coronary arteries, and intracranial cerebral arteries. Antibodies to sperm developed in all vasectomized monkeys, and complement and immunoglobulins were associated with atherosclerotic plaques in some of the vasectomized animals. The immunological response to sperm antigens that often accompanies vasectomy may exacerbate atherosclerosis.

Long-term vasectomy: effects on the occurrence and extent of atherosclerosis in rhesus monkeys

We demonstrated previously that atherosclerosis develops more extensively in vasectomized cynomolgus macaques fed an atherogenic diet and speculated that the immunologic response to sperm antigens may have exacerbated the atherosclerosis. We report here that rhesus monkeys vasectomized for 9-14 yr and fed monkey chow (devoid of cholesterol and low in fat) rather than an atherogenic diet also had more extensive and severe atherosclerosis than did control animals of the same age. The extent of atherosclerosis was considered as the percentage of intimal surface with plaques. No control animals were found to have plaques in the thoracic aorta, but 7 of 10 vasectomized monkeys were affected. The plaques in the vasectomized monkeys occupied about 13% of the intimal surface. In 4 of 7 control monkeys and 7 of 10 vasectomized monkeys there were lesions in the abdominal aortas; the lesions were considerably more extensive and severe in the vasectomized animals. Lesions were also more common in iliac arteries of vasectomized animals, and the extent was increased about threefold. Plaques were seen at the carotid bifurcation in all of the animals of both the control and vasectomized groups. The carotid bifurcation plaques of the vasectomized monkeys were larger than those of the control animals on the right but not on the left side. Histologically, the lesions of vasectomized monkeys did not appear to be qualitatively different from those of control animals, even though they were larger and contained more collagen, lipid, and mucopolysaccharides. Grossly, the distribution of the lesions in the vasectomized animals was different from that in the control animals, and that of lesions induced by atherogenic diets, i.e., the lesions were distributed randomly within the artery rather than around bifurcations. More extensive atherosclerosis was noted among vasectomized animals that were found to lack demonstrable circulating free antisperm antibodies. On the basis of the observations made in this study, we suggest that the antisperm antibodies that form after vasectomy may result in circulating immune complexes that exacerbate atherosclerosis.

Chronic testicular pain following vasectomy

The incidence of chronic testicular pain following vasectomy has not been previously assessed. We have carried out a survey by postal questionnaire and telephone interview of 172 patients 4 years after vasectomy to assess the incidence of chronic testicular pain. Significant early post-operative complications occurred in 6 patients (3.5%): 2 infection, 3 haematoma and 1 orchitis. Chronic testicular discomfort was present in 56 patients (33%), considered by 26 (15%) to be troublesome but not by the other 30 (17%). Testicular discomfort related to sexual intercourse occurred in 9 cases (5%). Of the 9 patients who had sought further medical help only 2 had had further surgery (1 an epididymectomy and 1 excision of a hydrocele). Only 3 patients regretted having had the vasectomy because of chronic pain. On ultrasound examination, epididymal cysts were a common finding on both asymptomatic and symptomatic patients following vasectomy. Prior to vasectomy, all patients should be counselled with regard to the risk of chronic testicular pain.

Epididymal extravasation following vasectomy as a cause for failure of vasectomy reversal

Twenty-eight men undergoing vasectomy reversal who were found to have no sperm in the proximal vas fluid on one or both sides underwent microscopic epididymal exploration. In 33 of 39 cases so explored, normal sperm were found in the epididymal fluid of the corpus, despite absence of sperm in the vas fluid. Epididymal histology distal to this site revealed extensive interstitial sperm granulomas resulting from rupture of the epididymal duct. Testicular biopsy revealed normal spermatogenesis. Secondary epididymal obstructions were noted when there was copious fluid in the vas deferens proximal to the vasectomy site as well as when there was scanty fluid. It is concluded that persistent azoospermia after an accurate microscopic vasovasostomy results from the secondary epididymal obstruction induced by rupture of the epididymal duct related to the pressure increase after vasectomy.

Open-ended vasectomy, sperm granuloma, and postvasectomy orchialgia

The presence of a sperm granuloma at the vasectomy site prevents epididymal pressure build-up, perforation, and the formation of an epididymal sperm granuloma. It thus enhances reversibility of the vasectomy and lessens the likelihood of epididymal discomfort. In two prospective vasectomy series, a sperm granuloma was intentionally allowed to form by not sealing the testicular end of the vas. The sperm granuloma resulted in no instance of orchialgia, but created a greater risk of spontaneous recanalization. This latter problem could only be solved by more careful sealing of the upper end of the vas. In a separate series of nine patients vasectomized elsewhere and specifically referred to us for chronic and persistent postvasectomy orchialgia, seven had no sperm granuloma at the vasectomy site. Pain in these cases was localized in the epididymis and was relieved by vasovasotomy. Any technique of vasectomy carries a very small risk of orchialgia, whether due to the presence of a sperm granuloma at the vasectomy site or to increased epididymal pressure.

Vasectomy and prostate cancer risk

To assess the hypothesis that a history of vasectomy is a risk factor in the etiology of prostate cancer, the authors conducted a case-control study at Roswell Park Memorial Institute, Buffalo, NY, between 1982 and 1988. From epidemiologic data routinely collected from entering patients, information on vasectomy history and other data were obtained for 614 patients with prostate cancer and 2,588 comparable control subjects with cancer at another site. Age-specific and age-adjusted relative risks were calculated. Increased risk (relative risk = 1.7, 95% confidence interval 1.1-2.6) was found for reporting vasectomy at any age. Age-adjusted relative risk of 2.2 (95% confidence interval 1.0-4.6) was observed for men who reported vasectomy 13-18 years before diagnosis. A significant trend in the association of years since vasectomy and risk also was observed. Cases and controls were found to be nearly identical with respect to education, income, race, marital history, and number of children. A difference in smoking histories of cases and controls was found not to confound the observed associations. These data may suggest the importance of further epidemiologic and biologic research on vasectomy as a risk factor for prostate cancer.

Chronic testicular pain: an overview

Chronic testicular pain (orchialgia, orchidynia or chronic scrotal pain) is common and well recognized but its pathophysiology is poorly understood. Currently treatment is largely empirical. This article aims to present an overview of its prevalence, possible aetiology and the available treatment options. The contribution of psychological factors is unclear, although some of these patients undoubtedly are depressed. Post vasectomy chronic testicular pain may be due to functional obstruction of the vas, or to spermatic granuloma. The surgical technique used may be relevant and the application of intraoperative local anaesthetic may have a role in reducing the risk. The importance of the sympathetic nervous system and the role of a possible alteration of the adrenergic receptors of the vas deferens in patients with chronic testicular pain are discussed. For patients failing to respond to conservative treatment, microsurgical denervation of the spermatic cord, epididymectomy and vasovasostomy have all shown a degree of relief. Unfortunately a small number of patients fail to respond to both conservative and more invasive treatment methods and for them the only available therapeutic option is inguinal orchiectomy.

Vasectomy and the risk of prostate cancer

An unexpected association between history of vasectomy and increased risk of prostate cancer emerged when multiple comparisons were carried out in data collected from 1976-1988 in a US hospital-based case-control study of many diseases and exposures. The association was assessed in detail in these data, in a comparison of 220 men with first episodes of prostate cancer with 571 noncancer controls and 960 cancer controls. The age-adjusted relative risk of prostate cancer was 5.3 (95% confidence interval 2.7-10) when noncancer controls were used and 3.5 (95 percent confidence interval 2.1-6.0) when cancer controls were used. The magnitude of the relative risk estimate appeared to be unrelated to the length of the interval after vasectomy. Allowance for several factors did not alter the estimates, but we did not have information on testosterone level or sexual activity, which may have been confounding factors. The association was stronger among men most likely to have been under more intensive medical surveillance; selective detection of asymptomatic cancer in such men would have led to an excess of cases. Further studies are needed to rule out chance, bias from medical surveillance, and uncontrolled confounding as explanations for the finding.

No-scalpel vasectomy at the King's birthday vasectomy festival

No-scalpel vasectomy was developed to increase acceptability of vasectomy by elimination of the fear of the incision. Although this method has been used for over 8,000,000 men, the technique is largely unknown in developed countries. During the King's birthday vasectomy festival no-scalpel vasectomy was compared with standard incisional vasectomy in 1203 patients. An average of 57 procedures per day could be done by each physician with the no-scalpel method, compared to 33 procedures with the standard method (p less than 0.001). The complication rate was 0.4/100 procedures for no-scalpel vasectomy compared with 3.1/100 for standard vasectomy (p less than 0.001). No-scalpel vasectomy is a rapid and economic alternative to standard vasectomy, with fewer complications and increased patient acceptability.

Epididymectomy for post-vasectomy pain: histological review

Fifteen epididymectomies were performed on 10 patients with post-vasectomy pain and 12 specimens were available for histopathological review. The findings were compared with those in 2 groups in which epididymectomy was performed for chronic epididymo-orchitis and epididymal cysts. The results showed that 50% of the post-vasectomy group were cured by simple epididymectomy. Pathological findings revealed features of long-standing obstruction and interstitial and perineural fibrosis which may have accounted for the pain. It is important to recognise this late complication of vasectomy and, if surgery is to be performed, to include all of the distal vas and previous vasectomy site in the excision.

Complications of vasectomy

INTRODUCTION

Vasectomy is a common method of sterilisation. However, it is less popular than tubal ligation world-wide. It is also a frequent cause of litigation relating to its complications. This article reviews the early and late risks associated with the procedure.

PATIENTS AND METHODS

Data collection was done using the internet to search Medline for obtaining evidence-based medicine reviews. Cross-references were obtained from key articles. Websites of government bodies and medical associations were searched for guidelines relating to vasectomy.

DISCUSSION

Early complications include haematoma, wound and genito-urinary infections, and traumatic fistulae. Vasectomy failure occurs in 0-2% of patients. Late recanalisation causes failure in 0.2% of vasectomies. Significant chronic orchalgia may occur in up to 15% of men after vasectomy, and may require epididyectomy or vasectomy reversal. Antisperm antibodies develop in a significant proportion of men post-vasectomy, but do not increase the risk of immune-complex or atherosclerotic heart disease. Similarly, vasectomy does not enhance risk of testicular or prostate cancer. Vasectomy has a lower mortality as compared to tubal occlusion, but is still significantly high in non-industrialised countries because of infections.

CONCLUSIONS

Vasectomy, though safe and relatively simple, requires a high level of expertise to minimise complications. Adequate pre-operative counselling is essential to increase patient acceptability of this method of permanent contraception.

Pulsed radiofrequency as a treatment for groin pain and orchialgia

Inguinal and testicular pain are challenging problems for which no reliable, standardized treatment exists. We report 3 patients with groin pain or orchialgia who were treated with pulsed radiofrequency of the nerves innervating these areas. All 3 patients reported complete pain relief at their 6-month follow-up visits. The techniques and settings used for the nerve blocks and radiofrequency procedures are explained in detail, along with a brief synopsis of the rationale for using it. Randomized, placebo-controlled studies are needed to better assess the efficacy of this procedure and identify eligible candidates.

The association between vasectomy and prostate cancer: a systematic review of the literature

OBJECTIVE

To evaluate the possible association between vasectomy and prostate cancer.

DESIGN

Systematic review of the literature.

PATIENT(S)

Fourteen original studies published between January 1985 and December 1996 that addressed the association between vasectomy and prostate cancer.

MAIN OUTCOME MEASURE(S)

The strength of the association was estimated with the use of a meta-analysis (DerSimonian and Laird method). A sensitivity analysis was conducted to assess the impact of different sources of heterogeneity.

RESULT(S)

Fourteen original papers were reviewed (5 cohort and 9 case-control studies). Relative risks ranged between 0.44 (95% confidence interval [CI] = 0.1-4.0) and 6.70 (95% CI = 2.1-21.6). The overall relative risk (DerSimonian and Laird estimate) was 1.23 (95% CI = 1.01-1.49). The sensitivity analysis showed that this measure was very sensitive to the study base, the type of design used, and the possibility of bias. Further, the funnel plot demonstrated the probable existence of publication bias.

CONCLUSION(S)

No causal association was found between vasectomy and prostate cancer. Individuals who have undergone vasectomy are not at high risk for the development of prostate cancer.

Immunological and morphological effects of vasectomy in the rabbit

Half of the rabbits developed antisperm antibodies (measured by either indirect immunofluorescence or sperm immobilization tests) after either a unilateral or bilateral vasectomy. The raised antibody levels, particularly six months or longer after vasectomy, often accompanied patchy orchitis. Seminiferous tubules from such animals exhibited sloughed, multinucleated, and immature germinal cells which were engulfed by phagocytic cells. Mononuclear infiltrates were occasionally present. The basal lamina infolded and thickened by means of supernumerary layers and appeared to be endocytosed by cells of the seminiferous tubules. Four months after vasectomy, numerous phagocytic cells were seen in migrate through the intact epithelium of zone 1 in the caput epididymidis, and were particularly prevalent in animals that exhibited testicular damage. These macrophages may serve to present sperm antigens to lymphocytes.

Vasectomy and risk of prostate cancer

CONTEXT

Vasectomy is a common method of contraception, but concern exists about a reported association with risk of prostate cancer.

OBJECTIVE

To examine whether vasectomy increases risk of prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

National population-based case-control study of 923 new cases of prostate cancer among men aged 40 to 74 years from the New Zealand Cancer Registry who were on the general electoral roll. Controls (n = 1224) were randomly selected from the general electoral roll, with frequency matching to cases in 5-year age groups. Cases (3-15 months after diagnosis) and controls were interviewed by telephone between January 1997 and November 1999.

MAIN OUTCOME MEASURES

Relative risk (RR) of prostate cancer for men who had had a vasectomy vs those who had not.

RESULTS

There was no association between prostate cancer and vasectomy (RR, 0.92; 95% confidence interval [CI], 0.75-1.14) nor with time since vasectomy (RR, 0.92; 95% CI, 0.68-1.23 for > or = 25 years since vasectomy). Adjustment for social class, geographic region, religious affiliation, and a family history of prostate cancer did not affect these RRs.

CONCLUSIONS

Vasectomy does not increase the risk of prostate cancer, even after 25 years or more.

Sperm autoantibodies in vasectomized rats of different inbred strains

An immune response to antigens of spermatozoa occurs after vasectomy in rats of some inbred strains, but not in others. Antibodies to rat spermatozoa were detected by indirect immunofluorescence in some of the serums of vasectomized rats of the following strains: 80 percent of Lewis, 47 percent of Brown Norway, 13 percent of Buffalo, 12 percent of Wistar-Furth, and 11 percent of ACI rats. No such antibodies were detected in the serums of vasectomized Fischer, Dark Agouti, and Sprague-Dawley rats.

Vasectomy and prostate cancer: results from a multiethnic case-control study

BACKGROUND

Vasectomy, a widely used form of contraception, has been associated in some studies with increased prostate cancer risk.

PURPOSE

We assessed this association on the basis of data collected in a large multiethnic case-control study of prostate cancer that was conducted in the United States (Los Angeles, San Francisco, and Hawaii) and Canada (Toronto and Vancouver).

METHODS

In home interviews conducted with newly diagnosed prostate cancer case patients and population control subjects, we obtained information on the participants' medical history, including a history of vasectomy and the age at which the procedure was performed, as well as other potential risk factors. Blood samples were collected from control subjects only and were assayed for concentration of sex hormones and sex hormone-binding globulin.

RESULTS

The present analysis was based on 1642 prostate cancer patients and 1636 control subjects. A history of vasectomy was not significantly associated with prostate cancer risk among all racial/ethnic groups combined (odds ratio [OR] = 1.1; 95% confidence interval [CI] = 0.83-1.3), whites (OR = 0.94; 95% CI = 0.69-1.3), blacks (OR = 1.0; 95% CI = 0.59-1.8), or Chinese-Americans (OR = 0.96; 95% CI = 0.42-2.2). Among Japanese-Americans, the OR was 1.8 (95% CI = 0.97-3.4), but the statistically nonsignificant elevation in risk was limited to more educated men and those with localized cancers. ORs did not vary significantly by age at vasectomy or years since vasectomy. We found a lower serum concentration of sex hormone-binding globulin and a higher ratio of dihydrotestosterone to testosterone among vasectomized control subjects than among nonvasectomized control subjects.

CONCLUSIONS

The findings of this study do not support previous reports of increased prostate cancer risk associated with vasectomy. However, the altered endocrine profiles of vasectomized control subjects seen in this cross-sectional comparison warrant further evaluation in longitudinal studies.

Incidence of disease after vasectomy: a record linkage retrospective cohort study

OBJECTIVE

To determine whether vasectomy is associated with an increased risk of several diseases, and in particular testicular cancer, after operation.

DESIGN

Retrospective cohort study using linked medical record abstracts.

SETTING

Six health districts in Oxford region.

SUBJECTS

13,246 men aged 25-49 years who had undergone vasectomy between 1970 and 1986, and 22,196 comparison subjects who had been admitted during the same period for one of three specified elective operations, appendicitis, or injuries.

MAIN OUTCOME MEASURES

Hospital admission and death after vasectomy or comparison event.

RESULTS

The mean durations of follow up were 6.6 years for men with a vasectomy and 7.5 years for men with a comparison condition. The relative risk of cancer of the testis in the vasectomy cohort (4 cases) compared with that in the other cohorts (17 cases) was 0.46 (95% confidence interval 0.1 to 1.4), that of cancer of the prostate (1 v 5 cases) 0.44 (0.1 to 4.0), and that of myocardial infarction (97 v 226 cases) 1.00 (0.8 to 1.3). There was no evidence of an increase associated with vasectomy in the incidence of a range of other diseases.

CONCLUSIONS

Vasectomy was not associated with an increased risk of testicular cancer or the other diseases studied. With respect to prostatic cancer, while we found no cause for concern, longer periods of observation on large numbers of men are required.

The incidence of chronic scrotal pain after vasectomy: a prospective audit

OBJECTIVE

To assess the extent of scrotal pain in men before and after vasectomy, to produce accurate data for the benefit of men considering this procedure, and hence improved informed consent about the outcomes, as chronic scrotal pain after vasectomy is a poorly quantified clinical problem.

PATIENTS AND METHODS

Between November 2004 and January 2006 nine surgeons carried out vasectomies in 625 men (mean age 39.9 years, sd 5.6) under local anaesthesia. A questionnaire was devised to establish the presence of any scrotal or testicular pain, and to characterize this discomfort; 6 months after the procedure a modified version of the same questionnaire was administered.

RESULTS

In all, 593 (94.7%) men returned the preoperative questionnaires and were entered into the study; 488 (82.2%) of these completed the follow-up questionnaire, giving a mean (sd) follow-up of 6.8 (1.6) months. In all, 65 men reported new-onset scrotal pain at 7 months (14.7%). The mean visual analogue score for this pain was 3.4/10. Four men (0.9%) in the responding group described pain after vasectomy as 'quite severe and noticeably affecting their quality of life'.

CONCLUSION

At 7 months after vasectomy about 15% of previously asymptomatic men have some degree of scrotal discomfort. These early data indicate that chronic scrotal pain after vasectomy is a genuine entity, but a longer-term follow-up in this group will be important to allow further evaluation of how this pain develops with time.

Risk of testicular cancer after vasectomy: cohort study of over 73,000 men

OBJECTIVE

To confirm or refute reports that vasectomy may increase the risk of cancers of the testis and prostate.

DESIGN

Computerised record linkage study of cohort of men with vasectomy and comparison of cancer rates with those in the whole Danish population; manual check of all records of patients with testicular and prostate cancer diagnosed within the first year of follow up.

SETTING

Denmark 1977-89.

SUBJECTS

Cohort of 73,917 men identified in hospital discharge and pathology registers as having had a vasectomy for any reason during 1977-89.

MAIN OUTCOME MEASURES

Observed incidences of testicular, prostate, and other cancers up to the end of 1989.

RESULTS

The overall pattern of cancer incidence in the study cohort was similar to that expected nationally. No increased incidence in testicular cancer was observed (70 cases; standardised morbidity ratio 1.01 (95% confidence interval 0.79 to 1.28)). The incidence during the first year of follow up was also close to that expected (nine cases; standardised morbidity ratio 0.80 (0.36 to 1.51)). The incidence of prostate cancer was not increased (165 cases; standardised morbidity ratio 0.98 (0.84 to 1.14)).

CONCLUSIONS

The incidence of testicular cancer in men with vasectomy is no higher than in other men. Vasectomy does not cause testicular cancer and does not accelerate the growth or diagnosis of pre-existing testicular neoplasms. Data concerning a causal relation between vasectomy and prostate cancer were inconclusive.