Genitourinary Malignancies in Transplant or Dialysis Patients: The Frequency of Two Newly Described 2016 World Health Organization Histopathologic Types.

BACKGROUND: The aim of this study was to revise the histopathologic types of neoplasias in the genitourinary tract and determine the frequency of 2 new entities included in the 2016 book of World Health Organization classification of renal tumors. It is not established so far whether these 2 recently described tumors are the most frequent in association with end-stage kidney disease. METHODS: In a retrospective analysis, we revised the histopathologic type of 37 genitourinary tumors from 21 patients in dialysis and/or submitted to renal transplantation from 2003 to 2016 aiming to find the frequency of acquired cystic disease-associated renal cell carcinoma and clear cell papillary (tubulopapillary) renal cell carcinoma. RESULTS: From the total of 37 tumors, 34 were from native end-stage kidneys, 1 from the pelvis of the transplant kidney, and 2 from the urinary bladder. The frequencies from native kidneys were: papillary carcinoma, 13/34 (38.2%); papillary adenoma, 9/34 (26.5%); acquired cystic disease-associated renal cell carcinoma, 4/34 (11.8%); oncocytoma, 3/34 (8.8%); conventional clear cell renal cell carcinoma, 3/34 (8.8%); and clear cell papillary (tubulopapillary) renal cell carcinoma, 2/34 (5.34%). The pelvis and urinary bladder tumors were high-grade urothelial carcinomas. The patients with urinary bladder tumors had been treated for polyomavirus infection. CONCLUSIONS: The frequencies of acquired cystic disease-associated renal cell carcinoma and clear cell papillary renal cell carcinoma were 11.8% and 5.9%, respectively. However, the spectrum of adenoma/carcinoma papillary tumors composed the majority, 64.7%, of tumors.

Lymphatic vessel density and expressions of lymphangiogenic growth factors in salivary carcinomas.

Nodal metastasis is an important prognostic indicator in head and neck cancers, including salivary carcinomas. In these, the risk for lymph node metastasis is variable and strongly associated with the tumor histologic type. The aim of the current study was to evaluate the lymphatic vessel density (LVD) and expressions of lymphangiogenic growth factors by tumor cells in different histologic types of salivary carcinomas subdivided according to the risk for nodal metastasis. In 15 high-risk (undifferentiated, high-grade mucoepidermoid and salivary duct carcinomas) and 60 low/moderate-risk tumors (adenoid cystic, low/intermediate-grade mucoepidermoid, acinic cell, myoepithelial, epithelial-myoepithelial and polymorphic low-grade carcinomas) the expressions of vascular endothelial growth factor-C (VEGF-C), hepatocyte growth factor (HGF) and D2-40 (for assessing LVD) were examined. No significant differences were encountered between high- and low/moderate/-risk carcinomas regarding LVD and VEGF-C or HGF expressions. Furthermore, the expression of these proteins did not correlate with LVD. Lymphatic vascular invasion was found mainly in high-risk carcinomas. Intratumoral LVD was significantly lower than peritumoral, regardless of the risk for metastasis and primary site of the lesion. The histologic types of salivary carcinomas which are associated with high-risk for nodal metastasis do not present increased LVD or VEGF-C and HGF expressions. The greater tendency for metastasis in these carcinomas seems to be related to their capacity to invade lymph vessels. Further studies on tumor cell interactions with lymphatic endothelial cells are needed to improve our understanding of the metastatic potential of salivary carcinomas.

Long-term nitric oxide deficiency causes muscarinic supersensitivity and reduces beta(3)-adrenoceptor-mediated relaxation, causing rat detrusor overactivity.

BACKGROUND AND PURPOSE: Overactive bladder is a complex and widely prevalent condition, but little is known about its physiopathology. We have carried out morphological, biochemical and functional assays to investigate the effects of long-term nitric oxide (NO) deficiency on muscarinic receptor and beta-adrenoceptor modulation leading to overactivity of rat detrusor muscle. EXPERIMENTAL APPROACH: Male Wistar rats received N(omega)-nitro-L-arginine methyl ester (L-NAME) in drinking water for 7-30 days. Functional responses to muscarinic and beta-adrenoceptor agonists were measured in detrusor smooth muscle (DSM) strips in Krebs-Henseleit solution. Measurements of [(3)H]inositol phosphate, NO synthase (NOS) activity, [(3)H]quinuclidinyl benzilate ([(3)H]QNB) binding and bladder morphology were also performed. KEY RESULTS: Long-term L-NAME treatment significantly increased carbachol-induced DSM contractile responses after 15 and 30 days; relaxing responses to the beta(3)-adrenoceptor agonist BRL 37-344 were significantly reduced at 30 days. Constitutive NOS activity in bladder was reduced by 86% after 7 days and maintained up to 30 days of L-NAME treatment. Carbachol increased sixfold the [(3)H]inositol phosphate in bladder tissue from rats treated with L-NAME. [(3)H]QNB was bound with an apparent K(D) twofold higher in bladder membranes after L-NAME treatment compared with that in control. No morphological alterations in DSM were found. CONCLUSIONS AND IMPLICATIONS: Long-term NO deficiency increased rat DSM contractile responses to a muscarinic agonist, accompanied by significantly enhanced K(D) values for muscarinic receptors and [(3)H]inositol phosphate accumulation in bladder. This supersensitivity for muscarinic agonists along with reductions of beta(3)-adrenoceptor-mediated relaxations indicated that overactive DSM resulted from chronic NO deficiency.