Moving towards the optimization of diagnosis for patients with sarcoma: A 10-year review of externally consulted sarcoma cases in a general anatomical pathology service.

INTRODUCTION: Soft tissue sarcomas (STS) are rare, diagnostically challenging, malignant tumors with diverse histomorphologic, immunohistochemical and molecular features. In our practice, STS are reported in a general anatomical pathology practice with no formal subspecialized training in reporting these complex specimens. Our study was performed to look at the rate of external consultation (EC), along with other parameters including discordance rate, associated diagnostic delay with EC and extent of secondary work-up performed by the consultant for correct diagnosis. METHODS: The reports from 880 soft tissue sarcomas cases in the province of Saskatchewan between January 1, 2010, and December 31, 2020, were analyzed descriptively. RESULTS: Of the 880 cases reviewed in our database, 51.9% (n = 457) cases were sent to 35 different North American institutions for expert opinion. The initial diagnosis and expert opinion were in full agreement for 182 cases (39.8%), while 194 cases (42.5%) had partial agreement and 66 cases (14.4%) had zero agreement. Of the cases that had zero agreement, 20 cases (4.4%) were initially diagnosed as malignant, with a benign opinion given by the expert; and 10 cases (2.2%) were initially diagnosed as benign, which were malignant upon expert review. CONCLUSION: Soft tissue sarcomas are complex tumors that frequently require expert opinion and integration of ancillary techniques with histomorphologic features for definitive classification. A multidisciplinary, subspecialized approach to STS and availability of necessary ancillary tests would improve diagnostic accuracy. In centers where the case load would not support the full-time expertise of an STS multidisciplinary team, criteria should be developed to effectively utilize EC practices.

Pigmented apocrine hamartoma: A distinct and uncommon pigmented lesion with dendritic melanocytes and appraisal of terminology.

A 20-year-old female presented to a gynecologist with an irregular, darkly pigmented, vulvar lesion. Histopathologic sections of a biopsy specimen showed cystically dilated glands with apical snouts, pigmented secretion, and numerous dendritic melanocytes. The lesion was diagnosed as a pigmented apocrine hamartoma of the vulva. We report the fifth case of this uncommonly encountered entity and discuss the conflicting terminology in the literature of this rare, pigmented lesion.

Pre-arrest doxycycline protects donation after circulatory death kidneys.

Kidney injury during donation after circulatory determination of death (DCDD) includes warm ischemic (WI) injury from around the time of asystole, and cold ischemic (CI) injury during cold preservation. We have previously shown that Matrix Metalloproteinases (MMPs) are involved in CI injury and that Doxycycline (Doxy), an antibiotic and known MMP inhibitor, protects the transplant kidney during CI. The purpose of our study was to determine if Doxy given before asystole can also prevent injury during WI. A rat model of DCDD was used, including Control, Preemptive Doxy (45 mg/kg iv), and Preemptive and Perfusion (100 microM) Doxy groups. Thirty minutes after asystole, both kidneys were removed. The left kidney was perfused at 4 °C for 22 h, whereas the right was used to establish the degree of warm ischemic injury prior to cold preservation. MMP-2 in the perfusate was significantly reduced in both treatment groups [Control 43.7 ± 7.2 arbitrary units, versus Preemptive Doxy group 23.2 ± 5.5 (p = 0.03), and 'Preemptive and Perfusion' group 18.0 ± 5.6 (p = 0.02)]. Reductions in NGAL, LDH, and MMP-9 were also seen. Electron microscopy showed a marked reduction in mitochondrial injury scores in the treatment groups. Pre-arrest Doxy was associated with a reduction in injury markers and morphologic changes. Doxy may be a simple and safe means of protecting transplant kidneys from both WI and CI.

Direction of the Biopsy Needle in Ultrasound-Guided Renal Biopsy Impacts Specimen Adequacy and Risk of Bleeding.

INTRODUCTION: Although medical factors such as hypertension and coagulopathy have been identified that are associated with hemorrhage after renal biopsy, little is known about the role of technical factors. The purpose of our study was to examine the effects of biopsy needle direction on renal biopsy specimen adequacy and bleeding complications. METHODS: Two hundred and forty-two patients who had undergone ultrasound-guided renal biopsies were included. A printout of the ultrasound picture taken at the time of the biopsy was used to measure the biopsy angle ("angle of attack" [AOA]) and to determine if the biopsy needle was aimed at the upper or lower pole and if the medulla was targeted or avoided. RESULTS: Of the 3 groups of biopsy angle, an AOA of between 50°-70° yielded the most glomeruli per core (P = .001) and the fewest inadequate specimens (4% vs 15% for > 70°, and 9% for < 50°, P = .038). Biopsy directed at a pole vs an interpolar region resulted in fewer inadequate specimens (8% vs 23%, P = .005), while biopsies that were medulla-avoiding resulted in fewer inadequate specimens (5% vs 16%, P = .004) and markedly reduced bleeding complications (12% vs 46%, P < .001) compared to biopsies where the medulla was entered. DISCUSSION: An AOA of approximately 60°, aiming at the poles, and avoiding the medulla were each associated with fewer inadequate biopsies and bleeding complications. While biopsy of the medulla is necessary for some diagnoses, the increased bleeding risk emphasizes the need for communication between nephrologist, pathologist, and radiologist.

Protection of the Transplant Kidney from Preservation Injury by Inhibition of Matrix Metalloproteinases.

BACKGROUND: Matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9, play an important role in ischemic injury to the heart, yet it is not known if these MMPs are involved in the injury that occurs to the transplant kidney. We therefore studied the pharmacologic protection of transplant kidneys during machine cold perfusion. METHODS: Human kidney perfusates were analyzed for the presence of injury markers such as cytochrome c oxidase, lactate dehydrogenase, and neutrophil-gelatinase associated lipocalin (NGAL), and MMP-2 and MMP-9 were measured. The effects of MMP inhibitors MMP-2 siRNA and doxycycline were studied in an animal model of donation after circulatory determination of death (DCDD). RESULTS: Markers of injury were present in all analyzed perfusates, with higher levels seen in perfusates from human kidneys donated after controlled DCDD compared to brain death and in perfusate from kidneys with delayed graft function. When rat kidneys were perfused at 4°C for 22 hours with the addition of MMP inhibitors, this resulted in markedly reduced levels of MMP-2, MMP-9 and analyzed injury markers. CONCLUSIONS: Based on our study, MMPs are involved in preservation injury and the supplementation of preservation solution with MMP inhibitors is a potential novel strategy in protecting the transplant kidney from preservation injury.