Prostate atrophy and spinal cord lesions

Tumour innervation and neurosignalling in prostate cancer

Prostate cancer progression has been shown to be dependent on the development of autonomic nerves into the tumour microenvironment. Sympathetic nerves activate adrenergic neurosignalling that is necessary in early stages of tumour progression and for initiating an angiogenic switch, whereas parasympathetic nerves activate cholinergic neurosignalling resulting in tumour dissemination and metastasis. The innervation of prostate cancer seems to be initiated by neurotrophic growth factors, such as the precursor to nerve growth factor secreted by tumour cells, and the contribution of brain-derived neural progenitor cells has also been reported. Current experimental, epidemiological and clinical evidence shows the stimulatory effect of tumour innervation and neurosignalling in prostate cancer. Using nerves and neurosignalling could have value in the management of prostate cancer by predicting aggressive disease, treating localized disease through denervation and relieving cancer-associated pain in bone metastases.

Risk of prostate cancer in men with spinal cord injury: A systematic review and meta-analysis

A lower risk of prostate cancer has been reported in men with spinal cord injury (SCI) as compared to that observed in able-bodied subjects. As injury-related consequences can have opposite effects on prostate pathophysiology, this meta-analysis aimed to (1) establish the existence/quantify the extent of decreased prostate cancer risk following SCI and (2) find out if there is any statistically significant difference in prostate-specific antigen (PSA) levels between SCI and able-bodied subjects. MEDLINE, Cochrane Library, Scopus, CINAHL, and ScienceDirect databases were used. Only studies reporting a prostate cancer diagnosis and/or PSA levels following SCI and in able-bodied controls were included. Five studies provided information about prostate cancer on 35 293 subjects with SCI and 158 140 controls. Six studies were included in PSA analysis which reported information on 391 men with SCI and 1921 controls. Pooled estimates indicated that SCI reduced the prostate cancer risk by approximately 50% as compared to controls, whereas differences in PSA levels were not statistically significant. Funnel plots suggested the presence of publication bias only in PSA analysis. Between-study heterogeneity was established and when, according to meta-regression models, analysis was restricted to studies including men with mean age over 55 years, prostate cancer risk in SCI decreased up to 65.0% than that in controls with no heterogeneity (P = 0.33, I² = 9%). In conclusion, in men over 55 years old, SCI decreases the prostate cancer risk up to 65.0% than that in controls. The large between-study heterogeneity on PSA confirms its poor reliability as a screening tool for prostate cancer in SCI.

Male fertility following spinal cord injury: an update

Spinal cord injury (SCI) occurs most often in young men at the peak of their reproductive health. The majority of men with SCI cannot father children naturally. Three major complications contribute to infertility in men with SCI: erectile dysfunction, ejaculatory dysfunction, and abnormal semen quality. Erectile dysfunction can be managed by regimens available to the general population, including oral administration of phosphodiesterase-5 (PDE-5) inhibitors, intracavernosal injections, vacuum devices, and penile prostheses. Semen may be obtained from anejaculatory men with SCI via the medically assisted ejaculation methods of penile vibratory stimulation (PVS) or electroejaculation (EEJ). Sperm retrieval is also possible via prostate massage or surgical sperm retrieval. Most men with SCI have abnormal semen quality characterized by normal sperm concentrations but abnormally low sperm motility and viability. Accessory gland dysfunction has been proposed as the cause of these abnormalities. Leukocytospermia is evident in most SCI patients. Additionally, elevated concentrations of pro-inflammatory cytokines and elevated concentrations of inflammasome components are found in their semen. Neutralization of these constituents has resulted in improved sperm motility. There is a recent and alarming trend in the management of infertility in couples with SCI male partners. Although many men with SCI have sufficient motile sperm in their ejaculates for attempting intrauterine insemination (IUI) or even intravaginal insemination, surgical sperm retrieval is often introduced as the first and only sperm retrieval method for these couples. Surgical sperm retrieval commits the couple to the most advanced, expensive, and invasive method of assisted conception: in vitro fertilization with intracytoplasmic sperm injection (IVF/ICSI). Couples should be informed of all options, including semen retrieval by PVS or EEJ. Intravaginal insemination or IUI should be considered when indicated.

Prostate cancer and neuroendocrine differentiation: more neuronal, less endocrine?

Neuroendocrine differentiation (NED) marks a structural and functional feature of certain cancers, including prostate cancer (PCa), whereby the malignant tissue contains a significant proportion of cells displaying neuronal, endocrine, or mixed features. NED cells produce, and can secrete, a cocktail of mediators commonly encountered in the nervous system, which may stimulate and coordinate cancer growth. In PCa, NED appears during advanced stages, subsequent to treatment, and accompanies treatment resistance and poor prognosis. However, the term “neuroendocrine” in this context is intrinsically vague. This article seeks to provide a framework on which a unified view of NED might emerge. First, we review the mutually beneficial interplay between PCa and neural structures, mainly supported by cell biology experiments and neurological conditions. Next, we address the correlations between PCa and neural functions, as described in the literature. Based upon the integration of clinical and basic observations, we suggest that it is legitimate to seek for true neural differentiation, or neuromimicry, in cancer progression, most notably in PCa cells exhibiting what is commonly described as NED.

Subcutaneous pellet testosterone replacement therapy: the "first steps" in treating men with spinal cord injuries

The authors describe the case of a 36-year-old man who presented with hormone level concerns 6 months after a rock climbing accident that resulted in paraplegia. Hypogonadism was diagnosed, and the patient received subcutaneous pellet testosterone replacement therapy. Within 6 months, the patient had substantial improvement in muscle function and was able to take several steps with the assistance of crutches or a walker. This case highlights the potential improvement in quality of life and overall prognosis resulting from the subcutaneous pellet form of testosterone when used as part of the overall treatment plan in such patients. Considering the overwhelming preponderance of hypogonadism in men with spinal cord injuries, the standard of care for such patients should include screening, laboratory hormone evaluation, and prompt treatment for testosterone deficiency.

Age-related changes in the innervation of the prostate gland: implications for prostate cancer initiation and progression

The adult prostate gland grows and develops under hormonal control while its physiological functions are controlled by the autonomic nervous system. The prostate gland receives sympathetic input via the hypogastric nerve and parasympathetic input via the pelvic nerve. In addition, the hypogastric and pelvic nerves also provide sensory inputs to the gland. This review provides a summary of the innervation of the adult prostate gland and describes the changes which occur with age and disease. Growth and development of the prostate gland is age dependent as is the occurrence of both benign prostate disease and prostate cancer. In parallel, the activity and influence of both the sympathetic and parasympathetic nervous system changes with age. The influence of the sympathetic nervous system on benign prostatic hyperplasia is well documented and this review considers the possibility of a link between changes in autonomic innervation and prostate cancer progression.

An introduction to acinar pressures in BPH and prostate cancer

Intra-acinar and peri-acinar pressures in the prostate might be key factors in the evolution of its zonal morphology and the pathogenesis of BPH and cancer. Herein, I hypothesize that intra-acinar pressures lead to a decrease in apoptosis by distending or stretching acinar epithelium and its surrounding stroma. Increased prostatic smooth muscle content and tone might generate peri-acinar pressures, which could, in the long-term, counteract intra-acinar pressures and decrease epithelial stretch. Thus, it is proposed that BPH (characterized by increased prostatic smooth muscle and, therefore, raised peri-acinar pressures) might decrease the risk of prostate cancer progression by counteracting intra-acinar pressures. In the context of this theory, the transition zone might have evolved as a specialized region within the prostate that can mount a concerted stromal-epithelial response to increased urethral and intra-acinar pressures (BPH), and the urethral angulation, anterior stroma and the prostatic capsule have an adjunctive evolutionary role in this phenomenon.

Prostate volume in male patients with spinal cord injury: a question of nerves?

OBJECTIVE

To assess the influence of standardized complete surgical deafferentation of the lower urinary tract by sacral deafferentation (SDAF) and sacral anterior root stimulation (SARS) on prostate volume in men with spinal cord injury (SCI).

PATIENTS AND METHODS

In a prospective study, the prostate volume of men with SCI who underwent SDAF/SARS was measured using transrectal ultrasonography. The prostate volumes of these men were compared with those of men with complete SCI but who did not undergo SDAF/SARS, those of men with incomplete SCI, and those of a historical sample of able-bodied men.

RESULTS

The median [25th;75th percentile] prostate volume of men who underwent SDAF/SARS (20.0 [14.0; 29.0]) and of men with complete SCI who did not undergo SDAF/SARS (20.0 [16.5; 29.0]) was significantly smaller than in the reference group (25.0 [5.0; 84.0]). The mean prostate volume was associated with age in the reference group (r = 0.185; P < 0.001) and in men with incomplete SCI (r = 0.284; P = 0.031), but not in men with complete SCI, irrespective of SDAF/SARS.

CONCLUSIONS

The prostate volume of men with complete SCI was significantly smaller than that of able-bodied men. Our data imply that sustained central innervation of the prostate plays an important role in prostate growth.

Evaluation of seminal zinc levels by atomic absorption in men with spinal cord injury

STUDY DESIGN

A case-control study evaluating seminal zinc level in spinal cord injury (SCI) patients.

OBJECTIVES

Patients with SCI have neurological prostate dysfunction. There are only some indications in the literature that seminal zinc level may be lower in these patients. Seminal zinc is mainly produced by the prostate and, therefore, can be considered to be a marker of prostate function. The objective of the present study was to determine whether SCI can induce changes in seminal zinc levels and to compare the results with those obtained for normal men (controls).

SETTING

The study was carried out in Brazil.

METHODS

A total of 24 men with SCI (mean age±s.d. 36.25±10.24 years) and 24 controls (mean age±s.d. 36.50±10.31 years) were studied. Blood and semen were collected after 3 days of abstinence from ejaculation. Semen was left at room temperature for 15 min, stored in liquid nitrogen, and lyophilized. Seminal zinc was determined by atomic absorption. Blood was stored at a controlled temperature of - 70 to -79 °C and later used for the determination of testosterone, prolactin and total prostate-specific antigen using an AxSYM apparatus and Abbott reagents.

RESULTS

Mean seminal zinc concentration was 85.20 mg l(-1) for the patients, a lower value than that obtained for the controls (147.16 mg l(-1)) (P=0.0035).

CONCLUSION

Patients with SCI have a significant reduction of seminal zinc.

Treatment of infertility in men with spinal cord injury

Most men with spinal cord injury (SCI) are infertile. Erectile dysfunction, ejaculatory dysfunction and semen abnormalities contribute to the problem. Treatments for erectile dysfunction include phosphodiesterase type 5 inhibitors, intracavernous injections of alprostadil, penile prostheses, and vacuum constriction devices. In anejaculatory patients who wish to father children, semen retrieval is necessary. Penile vibratory stimulation is recommended as the first line of treatment. Patients who fail penile vibratory stimulation can be referred for electroejaculation. If this approach is not possible, prostate massage is an alternative. Surgical sperm retrieval should be considered as a last resort when other methods fail. Most men with SCI have a unique semen profile characterized by normal sperm count but abnormally low sperm motility. Scientific investigations indicate that accessory gland dysfunction and abnormal semen constituents contribute to the problem. Despite abnormalities, sperm from men with SCI can successfully induce pregnancy. In selected couples, the simple method of intravaginal insemination is a viable option. Another option is intrauterine insemination. The efficacy of intrauterine insemination increases as the total motile sperm count inseminated increases. In vitro fertilization and intracytoplasmic sperm injection are options in cases of extremely low total motile sperm count. Reproductive outcomes for SCI male factor infertility are similar to outcomes for general male factor infertility.

Effect of spinal cord injury upon prostate: adenocarcinoma of prostate in a spinal cord injury patient - a case report

Introduction

Case presentation

Conclusion

Evaluation of seminal citrate level by 1H nuclear magnetic resonance spectroscopy in men with spinal cord injury

STUDY DESIGN

A case-control evaluating seminal citrate in patients with spinal cord injury (SCI).

OBJECTIVE

Several studies have shown neurological prostatic dysfunction in patients with SCI, as confirmed by low levels of seminal prostate-specific antigen (PSA), which is used as a parameter of gland activity. However, seminal citrate, produced almost exclusively by the prostate, could also be used as a marker of prostate function. Thus, the objective of this study was to determine whether SCI causes any changes in seminal citrate concentration and to compare the results obtained for patients and healthy men (controls).

SETTING

The study was carried out in Brazil.

METHODS

We studied 30 men with SCI aged on average 37.77+/-10.04 years and 30 controls aged on average 38.03+/-10.06 years. Blood and semen samples were collected after 3 days of abstinence from ejaculation. Fifteen minutes after collection, semen was stored in liquid nitrogen and the samples were submitted to (1)H nuclear magnetic resonance ((1)H NMR). Serum was stored at a controlled temperature of -70 to -79 degrees C and later used for the determination of testosterone, prolactin and total PSA using an AxSYM instrument and Abbott reagents.

RESULTS

The median concentration of seminal citrate was significantly lower in patients than in controls (521.65 versus 858.30 mg per 100 ml, P<0.001).

CONCLUSIONS

Patients with SCI have a significant reduction of seminal citrate as a consequence of neurological dysfunction of the prostate.

Prostate growth and prevalence of prostate diseases in early onset spinal cord injuries

BACKGROUND

Controversial data on modifications of prostate size, function and disease of spinal cord injury (SCI) patients has been previously reported.

OBJECTIVE

An analytical observational cohort study on male SCI patients was planned in order to evaluate prostate gland growth, including benign prostatic hyperplasia in relation to the age of the patient at SCI onset. Additional evaluations considered hormonal and biochemical parameters and prostate cancer.

DESIGN, SETTING AND PARTICIPANTS

113 SCI patients (mean age 61.3) and 109 age-matched able bodied subjects (mean age 65.4) were enrolled and stratified according to the patient age at SCI onset (< or = 30, 31-49, and > or = 50 years).

INTERVENTION

A complete medical history was then collected from all SCI patients and able bodied subjects.

MEASUREMENTS

Total prostate antigen (PSA) and testosterone (T) serum levels and urine culture were collected. Digital rectal examination and transrectal ultrasonography were performed.

RESULTS AND LIMITATIONS

Patients with SCI showed PSA value and prostate size significantly lower than those observed in able bodied subjects, and an inverse relationship was observed in SCI patients between these two parameters and patient age at the time of lesion onset. T serum levels were lower in SCI patients when compared to able bodied subjects. No SCI patient presented prostate cancer, while 9.7% of control subjects were affected by prostate cancer.

CONCLUSIONS

Prostate volume and PSA levels are lower in SCI patients and are inversely related to the patient age at lesion onset. Whether this effect is mediated directly or indirectly by a impaired nerve supply to the prostate remains to be determined. Despite the present observation of reduced prostate disease, as during the last twenty years life expectancy in SCI patients has improved significantly, the need to screen these patients for the occurrence of prostate disease should not be disregarded.

Chapitre I - Les particularités du diagnostic précoce du cancer de la prostate en présence d’une vessie neurologique

Due to their increased life expectancy, a growing number of neurological patients, particularly spinal cord injury patients, develop prostate cancer. Although prostate cancer appears to be slightly less frequent in spinal cord injury patients than in the general population (level of proof 3b), especially in the case of high and severe spinal cord injury (level of proof 3b), there is evidence to suggest that prostate cancer is responsible for morbidity (level of proof 4) and excess mortality (level of proof 5) in neurological patients with a life expectancy greater than 10 or 15 years. According to urology society guidelines, prostate cancer screening should be proposed to neurological patients with a life expectancy greater than 10 or 15 years (level of proof 5), particularly paraplegics aged 50 to 60 or 65 years. As in the general population, this screening could be based on digital rectal examination and annual PSA assay, which can still be interpreted, even in patients performing intermittent catheterization (level of proof 3b). However; PSA cannot be used in patients with an indwelling catheter (level of proof 3b). The histological diagnosis is based on prostatic biopsies, which should probably be preceded by systematic urine culture with appropriate antibiotic therapy, if necessary, to limit the risk of infection (level of proof 5). The treatment of localized prostate cancer in neurological patients, as in the general population, is based on radical prostatectomy and external beam radiotherapy. The indication must be adapted to each patient, taking into account the voiding mode and urodynamic assessment of lower urinary tract function. Brachytherapy does not appear to be an appropriate treatment modality because of its adverse effects (level of proof 5).

Prostate-specific antigen and prostate volume in Korean men with spinal cord injury: a case–control study

STUDY DESIGN

Prospective, cross-sectional, case-control study.

SETTING

Outpatient department in Seoul, Korea.

OBJECTIVES

To assess prostate volume and serum prostate-specific antigen (PSA) levels in Korean men with spinal cord injury (SCI).

METHODS

A total of 31 SCI patients with ages ranging between 45 and 81 years old (median age, 58 years) were studied. Thirty-one age-matched individuals without SCI were enrolled in the study as controls. We tested PSA levels and performed transrectal ultrasonographies on all enrolled patients. Of the patients with SCI, 20 were evaluated for testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) levels.

RESULTS

Serum PSA levels and prostate volume parameters in the two groups had similar values: the median (5th-95th percentiles) serum PSA level was 1.56 ng/ml (0.12-9.77) for SCI patients and 1.04 ng/ml (0.50-2.98) for controls (P=0.481), whereas the median (5th-95th percentiles) prostate volume was 18.33 ml (10.16-76.78) for SCI patients and 20.80 ml (14.23-41.22) for controls (P=0.072). No significant differences were found when serum PSA levels and prostate volumes were compared according to SCI patient injury characteristics. Testosterone levels were lower than the normal range in 7 SCI patients (35%), LH was higher than the normal range in 10 SCI patients (20%), and FSH was higher than the normal range in eight SCI patients (40%). We observed an age-related increase in FSH levels (r=0.634, P=0.004), although hormone levels did not correlate with serum PSA levels and prostate volume parameters.

CONCLUSIONS

According to our results, serum PSA levels and prostate volume in Korean SCI patients are not different from those in uninjured men and are not affected by injury characteristics.

Prostate activity and prostate cancer in spinal cord injury

In addition to androgen, autonomic nerves may be involved in prostatic function. As patients with spinal cord injury (SCI) have impaired innervation of the prostate, the prostate volume and prostate-specific antigen (PSA) level in patients with SCI may be different from those of healthy men. Experiments in rats with SCI indicate that neurogenic factors play an important role in prostate growth and function but the same phenomena may not occur in men with SCI because the current animal models differ from clinical results in humans in several respects. Although many of studies indicate the importance of intact peripheral innervation on the secretory function of the prostate, the effect of more central denervation such as occurs in complete SCI at the cervical, thoracic, or lumbar levels on prostatic function is unclear. In addition, the impact of central nervous system injury on prostatic secretory activity, and consequently on serum PSA levels, is also not clear. Furthermore, the impact of hormonal changes on prostate cancer development and prognosis observed in patients with SCI may also be affected by the level of injury and patient age at the time of injury, which have not been studied. In this article, we review prostate activity and prostate cancer in SCI and discuss how they may relate to neurogenic factors.