Howard Lau

Renal cell carcinoma: stage, grade and histology migration over the last 15 years in a large Australian surgical series

Study Type – Therapy (case series) 
Level of Evidence 4

Stopping Anticoagulation Before TURP Does Not Appear to Increase Perioperative Cardiovascular Complications

OBJECTIVE To evaluate the impact of stopping anticoagulant medications prior to transurethral resection of the prostate on peri-operative cardiovascular complications. METHODS Retrospective series (305 patients) undergoing TURP at a tertiary hospital between 2006 and 2010. All men were evaluated in preadmission clinics with defined protocols, with a low threshold for cardiovascular investigation. Incidence of postoperative bleeding and cardiovascular and cerebrovascular events was determined for 3 patient cohorts: group A--where anticoagulants were ceased preoperatively; group B--who were not receiving any anticoagulants; and group C--who underwent TURP while taking aspirin. RESULTS Of 305 patients, 194 (64%) did not receive anticoagulation therapy, 108 (35%) stopped receiving anticoagulation therapy pre-TURP, and 3 (0.98%) underwent TURP while taking aspirin. Anticoagulants used were aspirin (22.6%), warfarin (4.9%), antiplatelets (4.9%), and combination treatments (3.9%). Incidence of postoperative hemorrhage (early and delayed) was not significant (P = .69) between group A (10/108) and group B (7/194). Transfusion rate was 0.6% (2/305). Overall incidence of cardiovascular events was 0.98% (group A, n = 1 vs group B, n = 2), and incidence of deep vein thrombosis (0.32%; group A, n = 0 vs group B, n = 1) was not statistically significant (P = .30 and P = .37, respectively). Overall incidence of cerebrovascular events (0.65%; group A, n = 1 vs group B, n = 1) was not significant (P = 1.00). There were no deaths. CONCLUSION Men who have discontinue anticoagulation therapy before TURP do not appear to have a higher incidence of cardiovascular or cerebrovascular events, or bleeding-associated morbidity. It is possible that the morbidity attributed to discontinuing anticoagulation in this population may be overemphasized. Larger prospective studies are needed to better evaluate this clinical problem.

The linear cutting stapler for enteric anastomosis : a new technique in pancreas transplantation

The drainage of pancreatic exocrine secretions following pancreas transplantation is an evolving area of surgical practice. We describe a new technique applying a 55 mm Linear Cutting Stapler (LCS) to create the duodenoenterostomy for enteric drainage of the pancreas transplant. Twenty simultaneous pancreas and kidney transplantations performed between April 2005 and March 2006 were reviewed. Using a prospective database and chart review, complications and outcome related to the new technique of exocrine drainage were described. During this 12 month period, 19 of 20 consecutive simultaneous pancreas and kidney transplantations have been performed using the linear cutting stapler techinque. No complications relating to the enteric anastomosis have been demonstrated. In our initial experience, use of the LCS is both safe and easy to perform.

En bloc paediatric kidney transplant: is this the best use of a scarce resource?

Background:  Kidney transplants using organs from paediatric cadaver donors are uncommon and technically difficult. It has become accepted practice to transplant both kidneys en bloc from donors of 5 years into a single recipient. We aim to compare outcomes of en bloc kidney (EBK) transplants versus single kidney (SK) transplants from cadaver donors of age 5 years and lesser.

Multidetector spiral CT renal angiography in the diagnosis of giant renal artery aneurysms

A case of giant renal artery aneurysm in a 63-year-old man is presented. Renal artery aneurysms are rare (incidence < 1%) and this case is one of the largest giant renal artery aneurysms recorded in the literature. This case also demonstrates the value of multidetector spiral computed tomographic renal angiography in the diagnosis, planning, and treatment of renal aneurysms.

Management of renal masses in transplant allografts at an Australian kidney-pancreas transplant unit.

Background A shift towards partial nephrectomy (PN) in the management of small renal cell carcinoma (RCC) in recent years has prompted a parallel change in the management of rare cases of transplant allograft RCC. There are currently no guidelines on the management of allograft RCC. We present our center experience and review the latest evidence for management of RCC in renal transplant allografts. Methods We performed a retrospective review of the transplant patient registry of a kidney-pancreas transplant center between 1984 and 2012. All confirmed allograft kidney RCC cases were included in this series. MEDLINE search of current literature on renal allograft RCC and selection of appropriate studies were conducted. Results A total of 1,241 patients had received either a living, cadaveric, or combined kidney-pancreas transplant at our center, and four cases of allograft RCC were identified. The first case underwent a radical nephrectomy given the central location of the tumor and his young age. The second case underwent an open PN in the setting of a central tumor with minimal morbidity. The third case involved multiple renal lesions that were subsequently treated with radiofrequency ablation (RFA). The fourth case underwent a non-ischemic open PN in the setting of a midpole tumor with minimal morbidity. There have been no cases of local recurrence or metastatic progression at median 21.5 months’ follow-up. Conclusion We have shown the safety and efficacy of minimally invasive techniques such as PN and RFA in a variety of tumors. We consider PN as an appropriate therapy for localized, clinical T1 allograft RCC tumors.

Renal Anastomosing Hemangiomas With a Diverse Morphologic Spectrum: Report of Two Cases and Review of Literature.

Benign vascular lesions have a diverse appearance and can be extremely difficult to classify. We present renal anastomosing hemangiomas from 2 patients that exemplify the potential diverse range of appearances that can occur in this recently described, rare variant of capillary hemangioma. The lesion from one patient was an intravenous hemangioma with closely packed, fenestrated vascular channels that were reminiscent of the splenic red pulp. Also, the endothelial cells contained hyaline globules. On the other hand, the second patient had multifocal tumor. The lesions showed more extensive hyalinization and vascular ectasia reminiscent of cavernous hemangioma. Extramedullary hematopoiesis was a feature in all the tumors, particularly in the second patient where numerous immature blasts were present within vascular spaces.

Experimental hyperacute rejection in pancreas allotransplants

A model of sensitization by intraperitoneal lymph node inoculation was developed to test the hypothesis that hyperacute rejection (HAR) could occur in sensitized recipients of vascularized pancreas allografts. Ten pairs of outbred mongrel dogs that were lymphocytotoxic cross-match assay negative were inoculated with homogenized lymph nodes on either three or four occasions at fortnightly intervals before renal transplantation. A renal allograft from the same donor was used to test the HAR response and to further enhance sensitization by rejection of a vascularized organ. Pancreas transplants were performed 2 weeks later, with biopsies of the graft and blood samples taken at 0, 10, 20, and 30 min and then at 30-min intervals until the grafts were no longer viable. All renal and pancreas grafts were rejected in a classical hyperacute pattern. Within 4 min of revascularization of the pancreas, central lobular hemorrhage and vascular congestion appeared, followed by general edema. Histology demonstrated parallel changes of edema, vascular congestion, necrosis, hemorrhage, and leukocytic infiltrate, which all preceded graft infarction. A sharp decline in both arterial and venous white blood cell count and platelets occurred within 10 min of revascularization with initial sequestration and subsequent release of platelets from the graft (P=0.02). In summary, HAR of the allografted pancreas can be observed by the surgeon within minutes of revascularization, with predictable macroscopic and microscopic changes. This study supports the use of routine lymphocytotoxic cross-match tests for all recipients of pancreas transplants and implies that particular care is warranted in regraft pancreas allograft recipients.

Are there anatomical barriers to laparoscopic donor nephrectomy

Background:  The aim of this study was to analyse the effect of the right donor kidney and multiple arteries, on donor and recipient outcomes in the era of laparoscopic live donor nephrectomy (LLDN).

The effect of venous drainage on glucose homeostasis after experimental pancreas transplantation.

In this canine study, glucose homeostasis after clinical pancreas transplantation is complex, with the relative effect of systemic versus portal delivery of insulin remaining unresolved. Thirty-two pancreatectomized dogs received either systemic venous drainage (SVD) with bladder exocrine drainage (n = 16), or portal venous drainage (PVD) with gastric exocrine drainage (n = 16). Cyclosporine (CsA) based immunosuppression was commenced on day -7. The effect of immunosuppression was a significant increase in fasting blood glucose (FBGL) (P = 0.002), fasting insulin (P = 0.024), AUC for insulin (P = 0.009), and K values decreased (P = 0.009). FBGL and K values remained abnormal after transplantation with no significant difference seen between SVD and PVD. However, fasting insulin became significantly lower after PVD and AUC insulin fell in both groups. CsA levels fell in both groups after transplantation, mirroring the fall in AUC insulin, and implicating CsA as a major cause of peripheral resistance to insulin. In conclusion, PVD did not demonstrate a significant advantage over SVD in handling an intravenous glucose challenge. The need for pancreatectomy in large animals may make them an unsatisfactory experimental model to evaluate the glucoregulatory effects of pancreas allotransplantation.