Eduardo Orihuela

Recent advances in the diagnosis and treatment of renal arteriovenous malformations and fistulas

Arteriovenous malformations remain relatively rare clinical lesions. However, with an increasing number of percutaneous renal procedures being performed, their overall incidence can be expected to increase. Congenital arteriovenous malformations usually present with hematuria, while acquired fistulas are more likely to present with hemodynamic changes, such as hypertension, cardiomegaly and congestive heart failure. Arteriography remains the principal method of diagnosis. However, newer imaging modalities such as CT, MRI and color duplex ultrasound may make significant contributions in the evaluation of these abnormalities (fig. 1). Surgery, whether nephrectomy or ligation of feeding vessels, has long been the standard treatment for symptomatic arteriovenous malformations or fistulas. The loss of normal renal parenchyma, migration of occluding agents or recanalization of abnormal vessels has limited the use of embolization as a method of treatment in the past. Recently, newer techniques and agents, such as pharmacoangiography and alcohol, have increased the efficacy of embolization therapy, either as an adjuvant to surgery, definitive therapy or palliation. Although to our knowledge there have been no controlled studies comparing surgical treatment versus embolization, certain recommendations can be made. Because of the decreasing morbidity and increasing efficacy, embolization should be attempted at the time of arteriography as a means of treatment for most arteriovenous malformations and fistulas. However, the choice of surgery, embolization or a combination must be individualized for each patient with regard to overall health, symptoms and manifestations of the fistula or malformation (fig. 2).

Development of Human Papillomavirus Type 16 Associated Squamous Cell Carcinoma of the Scrotum in a Patient with Darier's Disease Treated with Systemic Isotretinoin

In contrast to squamous cell carcinoma of the penis, scrotal carcinoma has historically been associated with exposure to environmental or industrial carcinogens and has only rarely been correlated with human papillomavirus. We report on a patient with squamous cell carcinoma of the scrotum in which human papillomavirus type 16 was integrated into the tumor cell genome, suggesting a causal role of human papillomavirus in the development of squamous cell carcinoma of the scrotum. Other unique features of our case include the presence of Dariers disease, an uncommon genodermatosis, and treatment with oral retinoids, which have prophylactic value in the prevention of cutaneous malignancies.

Renal and peri-renal abscesses in children: Proposed physio-pathologic mechanisms and treatment algorithm

Abstract.Renal and perinephric abscess in children are uncommon. Three basic pathophysiologic mechanisms are involved, namely, hematogenous spread, ascending infection and contamination by proximity to an infected area. Six pediatric patients diagnosed with renal abscess were treated at our institution from 1990–2000. Five patients were females; ages ranged from 3–17 years (mean 11.8 years). Diagnosis, as expected, was not readily apparent at presentation. Computerized tomography and renal sonograms were the most useful imaging modalities. Gram-negative bacteria were commonly isolated; only one patient grew Staphylococcus aureus. All patients received broad-spectrum intravenous antibiotics. Additional treatments consisted of percutaneous drainage (4 patients), exploratory laparotomy (1 patient, for presumed Wilms tumor) and nephrectomy (2 patients). A new classification of the etiologic mechanisms of this condition is proposed along with a simple and practical treatment algorithm.

Ductal prostate cancer: contemporary management and outcomes.

OBJECTIVES To evaluate contemporary management and outcomes of ductal prostate cancer (PCA). MATERIALS AND METHODS We reviewed all patients with ductal PCA and at least 6 months of follow-up seen at UTMB from 1990 to 2005, which comprised 17 patients (mean age: 67.7 years, range 55-87). At time of diagnosis, 11 patients had localized disease (Group 1) and 6 patients had distant metastasis (Group 2). RESULTS Treatment of Group 1 patients included radiation and endocrine treatment for at least 2 years (n = 7), radiation alone (n = 2), and radical surgery (n = 2). At a mean follow-up of 3.6 years (r = 1-12 years) 8 patients (67.7%) remained free of recurrence, 1 patient had biochemical recurrence alone, 1 patient had recurrence in the anterior urethra, and the other had progression with metastasis to the brain and subsequent death. In addition to metastasis to regional/distant lymph nodes and bone in Group 2, metastatic sites included brain (n = 1), peritoneum (n = 1), and lung (n = 1). Mean follow-up was 2.3 years (r = 8 months to 4 years). All patients received androgen deprivation. One patient had progression of disease despite lack of biochemical recurrence and is alive at 2.5 years. One patient died from other causes while the 4 remaining patients are in remission at last follow-up. CONCLUSIONS Contemporary management of localized ductal PCA with radiation and endocrine therapy yields adequate disease-free survival. Metastatic sites include brain, lung, peritoneum, and anterior urethra, and most patients respond well to endocrine treatment.

Accumulation of Porphyrins in Plasma and Tissues of Dogs after δ-Aminolevulinic Acid Administration: Implications for Photodynamic Therapy

Protoporphyrin accumulates in tissues after administration of delta-aminolevulinic acid, and can be used as a photosensitizer for photodynamic therapy. To determine the distribution of porphyrins in a large animal model after administration of this porphyrin precursor, delta-aminolevulinic acid was administered to anesthetized dogs (100 mg/kg body weight intravenously) and porphyrin concentrations were measured in tissues (liver, pancreas, prostate, bladder, muscle and skin), plasma and urine for 6-10 h. Porphyrins increased markedly (up to 50-fold) in plasma within 1 h, were still markedly increased at 8 h, and consisted mostly of coproporphyrin III and protoporphyrin. Tissue porphyrin concentrations increased more slowly, were highest in liver, pancreas and prostate 7-10 h after delta-aminolevulinic acid administration, and were predominantly protoporphyrin. Maximum porphyrin concentrations in liver were 3- and 4-fold higher than in pancreas and prostate, respectively. Urinary delta-aminolevulinic acid excretion increased and was greatest 2-4 h after dosing; urinary porphobilinogen and porphyrins increased more gradually and remained increased up to at least 8 h. Coproporphyrin III was the predominant porphyrin in urine at all times, but hepta-, hexa- and pentacarboxyl porphyrins increased proportionally after administration of delta-aminolevulinic acid. These results indicate that porphyrins accumulate in plasma as well as tissues and urine after administration of delta-aminolevulinic acid, and may contribute to tumor necrosis during photodynamic therapy.

Histopathological Evaluation of Laser Thermocoagulation in the Human Prostate: Optimization of Laser Irradiation for Benign Prostatic Hyperplasia

We have previously shown in a canine prostate model that a noncontact low power neodymium:YAG laser regimen of 15 watts for 180 seconds yields a larger volume of coagulation necrosis than the currently recommended high power regimen of 50 watts for 60 seconds. These 2 regimens have not yet been compared in humans. The objective of this study was to evaluate histopathologically the thermocoagulation effect of these 2 laser regimens in the human prostate and the effect of the spatial distribution of the laser lesions on the extent of coagulation necrosis. The study was conducted in 10 patients undergoing radical prostatectomy or cystoprostatectomy. The laser treatment was given transurethrally 1 hour before removal of the specimen. There were no fractures of the prostate. The coagulation necrosis did not reach the peripheral zone and it was minimal in areas rich in fibromuscular tissue, such as the bladder neck. At times, nodular benign prostatic hyperplasia was unaffected. A 4-quadrant treatment in the same plane often yielded small nonconfluent lesions. Confluent lesions in the same plane yielded approximately 30% greater depth of coagulation necrosis, which was achieved when 3 or 4 lesions were created on each side of the prostate (per single transverse plane). Likewise, coagulation necrosis observed with 15 watts for 180 seconds was approximately 40% greater than that noted with the 50 watts for 60 seconds regimen. Our findings suggest that noncontact laser prostatectomy is a safe procedure that can be improved by modifying the laser regimen and the spatial distribution of lesions.

Breast masses associated with adenocarcinoma of the prostate

A breast mass in a man with carcinoma of the prostate may represent metastatic disease or, less often, a primary carcinoma of the breast. Advances in the differentiation of these lesions and a comparison of treatment regimes are discussed.

Human papillomavirus 16 exhibits a similar integration pattern in primary squamous cell carcinoma of the penis and in its metastasis

Background. Human papillomaviruses (HPV) are among the most common causes of sexually transmitted viral infections in the United States, and HPV types 16, 18, and others have been strongly linked with the development of cervical cancer. DNA from these oncogenic HPV types also has been detected in biopsy specimens of penile intraepithelial and invasive neoplasms, indicating a causal role of these viruses in the malignant transformation of these tissue.

Leiomyosarcoma of the penis

The third case of leiomyosarcoma of the foreskin is reported. A review of the literature indicates that this lesion, which is similar to cutaneous leiomyosarcoma that is seen elsewhere in the body, has a low grade of malignancy. This finding is in contrast to leiomyosarcoma of the penis, which arises in deep structures and tends to metastasize. Circumcision appears to be the most effective treatment for leiomyosarcoma of the foreskin.

Acute Renal Failure due to Rhabdomyolysis Associated with Radical Perineal Prostatectomy

We report a case of acute renal failure due rhabdomyolysis as a result of the exaggerated lithotomy position during radical perineal prostatectomy. The pathogenesis, diagnosis, management, and preventive measures of acute renal failure associated with rhabdomyolysis are also reviewed.