Impact of retroperitoneal tumors on the digestive tract (Review).

Primary retroperitoneal tumors are a rare group of neoplasms that often prove to be a real therapeutic challenge. The clinical picture is in most cases nonspecific, being the result of nearby tissue and organ compression, displacement and/or invasion, and it usually includes a variety of deceiving signs and symptoms that may lead to diagnostic errors. During the course of the disease, up to half of the patients diagnosed with retroperitoneal tumors can develop gastrointestinal symptoms, the incidence of such symptoms significantly increasing with tumor size. Therefore, symptoms such as abdominal distension, diffuse abdominal pain or epigastric pain mimicking acute pancreatitis, diarrhea, constipation, jaundice, hematemesis, melena and hematochezia can be found. The mainstream treatment for primary retroperitoneal tumors is surgical excision, chemotherapy and radiotherapy but associated with poor results. Due to their rarity, as well as to the complexity of these tumors, patients should be managed in high volume centers that allow the possibility of a multidisciplinary approach.

Renal tumor biomarkers (Review).

One of the most common types of cancer worldwide (9th most commonly diagnosed) is renal cell carcinoma (RCC). It is more common in developed countries and it usually develops in individuals between 60 and 70 years of age. The earlier the disease is identified, the lower the morbidity. Therefore molecular markers that exist in blood and urine may be used for earlier detection and diagnosis but also for the follow-up of the patient after treatment, whether surgical or oncological. The trend is to analyze the gene and protein expression as they constitute a source for new biomarkers. These markers are promising but in clinical practice regarding disease management, they are rarely used. Biological markers can be employed in many tumors because they can identify the prognostic value for individual treatment. However, markers for RCC are not validated, and their analysis is currently under investigation. Previous findings have demonstrated that the metastatic potential of RCC can be predicted using the biological features of the tumor cell. It is believed that the transformation from epithelial to mesenchymal phenotype gives the tumor cell the ability to metastasize. The purpose of this review was to identify the most valuable tumor markers that can be clinically used for the prognosis, treatment and follow-up of patients with renal tumors.

Tumoral markers in bladder cancer (Review).

Bladder tumors are frequently diagnosed urologic malignant diseases with an extremely high recurrence rate compared to other neoplastic tumors. Urothelial bladder carcinomas are mostly identified in their incipient form, as non-muscle invasive, but despite that, a third of them develop into aggressive recurrent disease. The diagnosis of bladder carcinoma at this moment is established using cytology and cystoscopy and is a great challenge for clinicians due to the lack of sensitivity. Urinary biomarkers could improve and enhance the diagnosis and screening techniques and determine a more accurate recurrence rate. However, bladder cancer is a heterogeneous disease and the existence of a single marker test with reduced cost is unlikely; thus, until then, the use of a panel of markers to obtain valuable information is inevitable even though suboptimal for use. To improve this deadlock, new biomarker panels should be identified and prepared to equalize the cost-efficiency balance. The present paper is a literature review concerning the most commonly used tumor markers in urinary bladder cancer as well as the most commonly encountered genetic modifications in such patients.

Oxidative Stress: A Possible Trigger for Pelvic Organ Prolapse.

Pelvic organ prolapse is a frequent health problem in women, encountered worldwide, its physiopathology being still incompletely understood. The integrity of the pelvic-supportive structures is a key element that prevents the prolapse of the pelvic organs. Numerous researchers have underlined the role of connective tissue molecular changes in the pathogenesis of pelvic organ prolapse and have raised the attention upon oxidative stress as an important element involved in its appearance. The advancements made over the years in terms of molecular biology have allowed researchers to investigate how the constituent elements of the pelvic-supportive structures react in conditions of oxidative stress. The purpose of this paper is to underline the importance of oxidative stress in the pathogenesis of pelvic organ prolapse, as well as to highlight the main oxidative stress molecular changes that appear at the level of the pelvic-supportive structures. Sustained mechanical stress is proven to be a key factor in the appearance of pelvic organ prolapse, correlating with increased levels of free radicals production and mitochondrial-induced fibroblasts apoptosis, the rate of cellular apoptosis depending on the intensity of the mechanical stress, and the period of time the mechanical stress is applied. Oxidative stress hinders normal cellular signaling pathways, as well as different important cellular components like proteins, lipids, and cellular DNA, therefore significantly interfering with the process of collagen and elastin synthesis.

Malignant Priapism - What Do We Know About It?

Malignancy as an etiological factor involved in priapism pathogenesis is rare. Malignant priapism (MP) can arise as a result of penile tumor invasion, either from primary penile tumors or from metastatic penile tumors, or due to hematological malignancies. Non-urological penile metastases are associated with significant worse prognosis compared to urological penile metastases, the appearance of priapism in such cases affecting even more the prognosis and the survival of these patients. Patients diagnosed with hematological malignancies and priapism present significant higher survival rates compared to those who develop MP in the context of a non-hematological malignancy, this being related to the fact that hematological malignancies are more sensitive to chemo- and radiotherapy. Most malignant priapism cases are ischemic; therefore the management should be based on the initial steps of the IP therapeutic protocol. Considering the trigger factor that has led to the priapic event specific oncologic treatment can be added as well.

Benefits of erectile function recovery programs after radical prostatectomy (Review).

Radical prostatectomy is one of the most frequent therapeutic options used for the management of patients diagnosed with prostate cancer. Normal erectile function after radical prostatectomy is a great problem for numerous patients and a real challenge for urologists worldwide. The advancements that have been made over the years in terms of minimally invasive surgery, as well as in terms of surgical techniques, have reduced the incidence of erectile dysfunction, but even so, its rate remains high and the post-operative recovery of erectile function is a long and costly process. Phosphodiesterase 5 inhibitors have provided excellent results and have become the first-line treatment for these patients, followed by intracavernous injections with alprostadil. Several studies have underlined the impact of phosphodiesterase 5 inhibitors in terms of preventing the fibrotic changes that are responsible for the irreversible erectile dysfunction. The general opinion is that an erectile function recovery process should be started as soon as possible after surgery to prevent the negative effects of neuropraxia.

Penile carcinoma and HPV infection (Review).

Penile carcinoma is a relatively frequent health issue in the developing countries such as Africa, Asia and South America, usually affecting men aged between 50 and 70 years. It is a highly treatable disease in its early stages, but has serious physical and psychological consequences. Usually, penile carcinoma is located in the penile glans, in approximately half the cases, with the most frequent histological type being squamous cell carcinoma with its microscopic subtypes. A large number of risk factors have been reported for this disease, having a multifactorial etiology, HPV infection being one of the most important factors involved in its appearance. Out of the HPV DNA positive genital cancers HPV-16 is the most frequently found type in men, followed by HPV-18. The evolution of penile cancer includes two independent carcinogenic pathways, related or unrelated to HPV infection. There is limited data available in literature regarding HPV-related neoplasia, as well as on the efficacy of vaccination in men, with studies still ongoing.

Mesh colposacropexy in the management of anterior vaginal compartment prolapse.

Pelvic organ prolapse is a frequent female pathology, often causing a negative impact on the patient's quality of life. The purpose of this paper is to present the results that we have achieved in 32 patients with anterior vaginal compartment prolapse, managed using the transvaginal mesh approach. Over a period of twelve months, we have performed 32 transvaginal reconstructive procedures using a four arms polypropylene mesh. The superior arms of the mesh have been passed through the obturator foramen while the inferior arms have been passed through the sacrospinous ligament. The surgery has lead to a significant improvement in the quality of life in this group of patients, this being assessed using self-administered questionnaires that evaluated the quality of life, the sexual function, and urinary continence. Anatomical success was achieved in 96.87% of the cases. In terms of postoperative complications, we mention one case of vaginal erosion, one case of de novo dyspareunia and three cases of pelvic discomfort. So far we have not encountered any mesh exposure cases nor prolapse recurrence. Considering the results that we have achieved in our study, we can conclude that the transvaginal polypropylene mesh approach can prove itself to be a viable solution for the management of genital prolapse, especially if we consider the high postoperative rates of anatomical success and low rates of postoperative complications, as well as improving the patient's quality of life. In spite of these encouraging results, the fact that in recent years FDA has emitted several warnings in terms of postoperative complications following such procedures, as well as the fact that our study was conducted on a small group of patients, limits the strength of our research, its only purpose being to present our experience for this surgical approach over a limited period of time.

Finite element dynamic analysis of soft tissues using state-space model.

A finite element (FE) model is employed to investigate the dynamic response of soft tissues under external excitations, particularly corresponding to the case of harmonic motion imaging. A solid 3D mixed 'u-p' element S8P0 is implemented to capture the near-incompressibility inherent in soft tissues. Two important aspects in structural modelling of these tissues are studied; these are the influence of viscous damping on the dynamic response and, following FE-modelling, a developed state-space formulation that valuates the efficiency of several order reduction methods. It is illustrated that the order of the mathematical model can be significantly reduced, while preserving the accuracy of the observed system dynamics. Thus, the reduced-order state-space representation of soft tissues for general dynamic analysis significantly reduces the computational cost and provides a unitary framework for the 'forward' simulation and 'inverse' estimation of soft tissues. Moreover, the results suggest that damping in soft-tissue is significant, effectively cancelling the contribution of all but the first few vibration modes.