Primary signet ring cell carcinoma of the prostate

Nine patients treated with primary signet ring cell carcinoma of the prostate were identified among 29,783 cases of prostate cancer evaluated at Mayo Clinic from January 15, 1970, until January 2, 2009. A PubMed search of the English-language literature published from January 1, 1980, to January 1, 2010, was then performed using the key words signet ring cell and prostate, identifying 42 cases. This study reviews those cases, along with the additional 9 reported herein, and evaluates clinical characteristics, histologic diagnoses, treatment modalities, and outcomes. Mean age at diagnosis was 68 years (range, 50-85 years), and mean prostate-specific antigen level was 95.3 ng/mL (range, 1.9-536.0 ng/mL; to convert to μg/L, multiply by 1). Most patients (66%) had non-stage IV carcinoma, the most common Gleason sum was 8 (33%), and mean survival was 29 months. The presence of a primary signet ring cell carcinoma of the prostate was best confirmed by negative findings on gastrointestinal work-up, a positive stain for prostate-specific acid phosphatase, and negative carcinoembryonic antigen test results.

Nephrocalcinosis: re-defined in the era of endourology

Nephrocalcinosis generally refers to the presence of calcium salts within renal tissue, but this term is also used radiologically in diagnostic imaging in disease states that also produce renal stones, so that it is not always clear whether it is tissue calcifications or urinary calculi that give rise to the characteristic appearance of the kidney on x-ray or computed tomography (CT). Recent advances in endoscopic imaging now allow the visual distinction between stones and papillary nephrocalcinosis, and intrarenal endoscopy can also verify the complete removal of urinary stones, so that subsequent radiographic appearance can be confidently attributed to nephrocalcinosis. This report shows exemplary cases of primary hyperparathyroidism, type I distal renal tubular acidosis, medullary sponge kidney, and common calcium oxalate stone formation. In the first three cases--all being conditions commonly associated with nephrocalcinosis--it is shown that the majority of calcifications seen by radiograph may actually be stones. In common calcium oxalate stones formers, it is shown that Randall's plaque can appear as a small calculus on CT scan, even when calyces are known to be completely clear of stones. In the current era with the use of non-contrast CT for the diagnosis of nephrolithiasis, the finding of calcifications in close association with the renal papillae is common. Distinguishing nephrolithiasis from nephrocalcinosis requires direct visual inspection of the papillae and so the diagnosis of nephrocalcinosis is essentially an endoscopic, not radiologic, diagnosis.

Randomized controlled, multicentre clinical trial comparing a dual-probe ultrasonic lithotrite with a single-probe lithotrite for percutaneous nephrolithotomy

OBJECTIVES

• To compare the Cyberwand (Gyrus/ACMI, Southborough, MA, USA), a dual-probe ultrasonic lithotrite, with a single-probe ultrasonic lithotrite. • The Cyberwand incorporates coaxial high- and low-frequency ultrasonic probes that work synergistically.

PATIENTS AND METHODS

• An institutional review board-approved, multicentre, randomized controlled trial to compare the Cyberwand to the Olympus LUS-II (Olympus America, Inc., Melville, NY, USA) single-probe lithotrite was performed. • Patients undergoing a percutaneous nephrolithotomy (PCNL) with a target stone > 2 cm in diameter were eligible for the study. • The primary outcome was the time to removal of the targeted stone.

RESULTS

• A total of 57 PCNLs were performed after randomization: 25 Cyberwand and 32 LUS-II. • There was no difference (P > 0.05) observed between the two devices for target stone surface area (Cyberwand 526.6 cm³ vs LUS-II 540.1 cm³), time to clearance of target stone (Cyberwand 15.8 min vs LUS-II 14.2 min) and target stone clearance rate (Cyberwand 61.9 mm²/min vs LUS-II 75.8 mm²/min). • Of the patients with stone analysis, hard stones (calcium oxalate monohydrate, brushite and cystine) were noted in 14 (56.0%) of the 25 Cyberwand and 18 (62.1%) of the 29 LUS-II patients. • Fifteen of the 25 (60.0%) Cyberwand and 20 of the 32 (62.5%) LUS-II patients were stone-free after the initial PCNL. • Those patients not rendered stone-free went on to receive a secondary PCNL. • Device malfunction occurred in eight of 25(32.0%) Cyberwand and five of 32 (15.6%) LUS II patients. • Complications were similar in both treatment groups.

CONCLUSION

• No appreciable difference between the dual-probe Cyberwand and the standard ultrasonic Olympus LUS-II lithotrites can be identified.

Accuracy of ultrasound in estimation of prostate weight: comparison of urologists and radiologists

INTRODUCTION

Measurements of prostate size are obtained to contribute in the diagnosis and follow up of patients with a variety of diseases. Since its introduction, transrectal ultrasonography (TRUS) of the prostate has become the most common method for assessment of prostate volumes. Ultrasonography, in general, has been associated with concerns of operator dependent variability. Herein, we analyze the accuracy of urologists and radiologists performing TRUS.

MATERIAL AND METHODS

The accuracy of preoperative TRUS prostate volume estimation was evaluated by comparing it to gross specimen prostate weight following robot-assisted radical prostatectomy (RARP) performed from August 2004 to March 2008 in Mayo Clinic Arizona. A total of 800 RARPs were evaluated retrospectively with 302 patients having a prostate volume measurement with TRUS at our institution followed by RARP being performed within 30 days. The TRUS measurements were divided into two groups: those TRUS measurements performed by urologists (group 1), and those performed by radiologists (group 2). The accuracy of the two groups were compared using a Pearson correlation analysis.

RESULTS

The estimated weight by TRUS in the total cohort of patients correlated with the pathological specimen weight at 0.802 with a standard error of 0.90. Group 1 performed a total of 114 ultrasounds with a correlation of 0.835 and a standard error of 1.27. Group 2 performed a total of 188 with a correlation of 0.786 and a standard error of 0.88.

CONCLUSIONS

Urologists and radiologists are both consistently within 17%-22% of the estimated prostate specimen weight. Urologists appeared to have a slightly higher accuracy in estimation but a higher range of error for the whole group when compared to radiologists. Transrectal ultrasonography is a reliable technique to estimate prostate weight and accuracy to within 20% of the pathological weight. Urologists and radiologists are essentially equally proficient in estimating prostate weight with TRUS. These findings are particularly important with respect to specialty certification and competency/proficiency evaluation, as health care increasingly moves towards outcomes based reimbursement.

Renal injury and the application of polysaccharide hemospheres: a laparoscopic experimental model

BACKGROUND AND PURPOSE

Microporous polysaccharide hemospheres (MPH) are hemostatic beads engineered from purified plant starch. MPH accelerates the natural clotting cascade by concentrating clotting factors and proteins on their surface while absorbing aqueous and low molecular weight components from blood. The purpose of this study was to determine the efficacy of MPH in achieving hemostasis in the setting of laparoscopic renal injury.

MATERIALS AND METHODS

In four domestic pigs, 16 laparoscopic renal trocar injuries were created (8 each of 12 and 5 mm). A standard hand-assisted laparoscopic approach was used to each kidney so that two lesions per kidney were randomly created. MPH was applied to each treatment lesion with light pressure maintained for 60 seconds. Four of the 16 lesions, two each of 12 and 5 mm, were allowed to bleed as controls. Hemostasis was defined as no active bleeding or oozing. The animals were sacrificed at the conclusion of the procedure.

RESULTS

The mean time to hemostasis for the 12-mm MPH and control lesions was 196.2 +/- 53.3 and 372.0 +/- 225.6 seconds, while the average blood loss was 8.3 +/- 3.7 and 12.0 +/- 4.9 g, respectively. For the 5-mm MPH and control lesions, the average time to hemostasis was 100.2 +/- 24.8 and 247.0 +/- 134.4 seconds, while the average blood loss was 8.3 +/- 3.8 and 9.0 +/- 0.7 g, respectively. The median number of applications of the MPH for the 5- and 12-mm injuries was 1 and 2, respectively.

CONCLUSIONS

MPH provided a rapid and effective means of hemostasis for laparoscopic renal parenchymal injuries in this model. Additional evaluation is warranted, however, before general application is advisable.

Thermal effects of laparoscopic saline-enhanced radiofrequency cautery on renal parenchyma in a porcine model

PURPOSE

Advances in the field of surgery have recently developed a number of devices and materials to improve surgical hemostasis. The effects of one such device, saline-cooled monopolar radiofrequency electrocautery, has been well scrutinized in splenic and hepatic applications. Despite the utilization of this device in urologic surgery, the classification of the thermal effects has been poorly characterized to date. The purpose of this study was to discern the thermal characteristics of the device in the laparoscopic environment when used on renal parenchyma.

MATERIALS AND METHODS

After institutional approval, four domestic swine were randomized to receive laparoscopic renal lesions randomly generated by either saline-cooled (25 W with saline flow rate of 4 mL/min) or standard monopolar radiofrequency electrocautery. The energy source was applied for between 1 and 11 seconds for each device in order to create a total of 64 renal lesions. Each kidney was harvested and examined by a genitourinary pathologist blinded to the treatment interval.

RESULTS

The saline-cooled device provided a greater depth of coagulation effect compared to standard monopolar electrocautery at all points in time (P < 0.05). The diameter of the lesions created using saline-cooled monopolar electrocautery was greater than those created with standard electrocautery (P < 0.05).

CONCLUSIONS

The saline-cooled monopolar electrocautery provided an improved coagulation effect compared to standard electrocautery in the laparoscopic setting. Recognition of the time and resultant thermal consequences can help the laparoscopic surgeon plan surgical approaches for renal lesions and improve hemostasis.

A new world revealed: early experience with digital ureteroscopy

PURPOSE

The latest digital ureteroscope, the DUR-D (Gyrus ACMI Inc., Southborough, Massachusetts) offers image quality that greatly exceeds current analog image capabilities. The purpose of this report was to document the applicability of this device in studying the earliest stages of stone formation.

MATERIALS AND METHODS

Symptomatic patients with nephrolithiasis (less than 1 cm in diameter) were prospectively enrolled and their renal papilla digitally mapped prior to stone removal. Recovered stones were photographed and analyzed using micro-computerized tomography. If the procedure could not be completed with the DUR-D, a conventional ureteroscope was used. Minors, pregnant patients and those with systemic disorders were excluded.

RESULTS

Eight patients (10 renal units), 2 cystine and 6 calcium oxalate stone formers, were studied with a mean age of 50.1 years. Excellent images were collected for all papilla except in 2 cases; a proximal ureteral stricture and acute angulation of the lower pole collecting system, respectively. There were no mechanical device failures. Of the 10 renal units 7 had stents postoperatively and there were no patient complications.

CONCLUSIONS

The ease of use and high quality images of digital ureterorenoscopy will allow the documentation of the earliest stages of calcium oxalate stone formation and, thereby, advance our understanding of the pathogenesis of calcium oxalate stone formation.

Bilateral laparoscopic nephrectomy for significantly enlarged polycystic kidneys: a technique to optimize outcome in the largest of specimens

OBJECTIVE

To present our experience with bilateral laparoscopic nephrectomy (BLN) for symptomatic autosomal-dominant polycystic kidney disease (ADPKD), as surgical management of massively enlarged polycystic kidneys can be a daunting task.

PATIENTS AND METHODS

The study was a retrospective chart review of all patients undergoing BLN for ADPKD. Patient demographics, indications for the procedure, perioperative data, and pathological data were analysed.

RESULTS

In all, 12 patients underwent BLN at our institution; eight were performed before transplant, three after transplant, and one with a concomitant kidney transplant. Indications for surgery included abdominal pain, fullness and early satiety, recurrent urinary tract infections, and need for space for future transplant. The mean patient age was 49.6 years, with a body mass index of 27.0 kg/m(2). The mean operative duration was 214 min, estimated blood loss was 169 mL, and the hospital stay was 4 days. There were no conversions to open surgery. The mean (range) pathological kidney mass was 2243 (656-4200) g on the left and 2379 (789-5042) g on the right. No patients with a previous renal transplant had deterioration in postoperative renal function. There was one minor intraoperative complication, one postoperative complication, and one patient with preoperative anaemia required a blood transfusion.

CONCLUSIONS

Symptomatic patients with ADPKD due to massively enlarged kidneys should be considered for BLN when performed by an experienced laparoscopic surgeon. This includes patients with an existing renal allograft and candidates for concomitant transplantation. The approach should be tailored to avoid injury to adjacent structures secondary to displacement from the mass effect of these kidneys.