Objective: Collecting duct carcinoma is a rare renal neoplasm arising from the epithelium of Bellini's ducts in the distal part of the nephron. Method: We describe our experience of this entity in University Hospital Galway with a series of four cases diagnosed between 2003 and 2011. Results: Three patients aged between 35 and 62 years presented with either lymph node or bone metastases without evident abdominal mass. In each case the biopsy from the metastatic lesion showed adenocarcinoma with an immunohistochemical profile suggestive of renal origin and a renal mass was subsequently confirmed by radiology. The fourth patient was an 81 year old male who presented with haematuria. Abdominal CT scan revealed a 5.6 cm mass in the right kidney extending into the renal vein. Biopsy of the renal mass in all cases confirmed adenocarcinoma with a tubular pattern with positive cytokeratin and Vimentin staining and CD10 negative staining. One patient was treated with nephrectomy with post-neoadjuvant chemotherapy and died 25 months after surgery. The other three patients died few months after their diagnosis. Conclusion: Collecting duct carcinoma is a rare renal neoplasm that can be difficult to diagnose on core biopsies, however, it can be identified based on radiological findings, gross, microscopic, histochemical and immunohistochemical features. Objective: Wilms Tumors (WT) is the most frequent renal tumor of children. Genetic alterations have been suggested as associated factors but the exact pathogenesis of WT is not fully characterized. Tissue factor (TF) is a glycoprotein which happens to be a key receptor for factor VII/VIIa and a primary initiator of coagulation. TF has also been associated with angiogenesis. Recent evidence pointed out an important role for TF in cancer progression and metastasis. Method: In the present investigation the differential expression of TF in WT was assessed by real-time PCR of RNA retrieved from paraffin sections using microdissection. Results: Different histological components of WT were analysed. The results revealed that TF was upregulated in blastema and epithelial components as compared to nonneoplastic tissue (14.38 and 16.02-fold respectively, P< 0.001). Stroma and non-neoplastic tissue presented low levels of TF expression. TF expression in WT metastatic lesions was also significantly upregulated as compared to non-metastatic WT. Microvessel density was positively correlated with TF expression (r=0.721). Conclusion: As described in other tumors, TF seems to play a significant role in the behavior of WT. Further investigations are warranted to better understand the pathways by which TF exerts its effects on tumor progression and its potential as a target for therapy. Objective: Biliary atresia (BA) is the most common neonatal cholestatic disorder and the prime indication for liver transplantation (LTx) in children. Histopathological markers in liver biopsies emerge promise as indicator of early LTx in patients with BA. Method: Ductular proliferation, ductal plate malformations and type I, III, IV and V collagen deposition were evaluated on Kasai portoenterostomy (KPE) and liver transplantation (LTx) biopsies from 36 children with BA. Formalin fixed and paraffin embedded liver biopsies were stained with hematoxylin-eosin, picrosirius-polarization and immunofluorescence methods. There were analyzed liver histoarchitecture, biliary ductus and collagen deposition in hepatic compartments. Pathologic findings were graded according to a 5-point semi-quantitative severity-based scoring system. Impact of these markers was tested on LTx time (<2 year and >2 year). Results: Median age of KPE was 12 weeks (range 6-20) and of LTx was 27 months (range 6-120). In KPE liver biopsies, ductular proliferation, ductal plate malformations and collagen deposition were increased but these parameters presented no association with clinical evolution for early LTx. Furthermore, collagen V prominent deposition was found along of hepatic sinusoids and type I, III and IV were more frequent in portal compartment. Conclusion: These results suggest that histopathological parameters evaluation presented may not determine early LTx in biliary atresia.