A comparison of stemmed and unstemmed components in revision knee arthroplasty

The purpose of the current study was to compare retrospectively the results of the Insall-Burstein constrained condylar knee implant used with and without intramedullary stems in 207 revision knee arthroplasties with the Insall-Burstein constrained condylar knee implant. One hundred sixty-one knees had either one or two stems placed. One hundred eight femoral stems and 76 tibial stems were placed. Fifty-five knees had no femoral or tibial stem. The average knee scores ranged from 52 preoperatively to 86 postoperatively. The average range of motion postoperatively was 4 degrees (range, 0 degrees -10 degrees ) to 106 degrees (range, 94 degrees -118 degrees ) in this group. The average postoperative knee score was 86 in the unstemmed group and 85 in the stemmed group with no difference in average range of motion. There were four (3%) cases of tibial loosening and two (2%) cases of femoral loosening in the unstemmed group. There were two (2%) cases of tibial loosening and two (2%) cases of femoral loosening at an average followup of 4.2 years (range, 2-6.2 years). Despite the higher constraint inherently designed in an Insall-Burstein constrained condylar knee component, the current study did not show a significantly higher loosening in implants without stems compared with implants used with stems. Therefore, the use of a semiconstrained component does not alone constitute a requirement for the use of an intramedullary stem.     

Human papillomavirus (HPV)-related oropharyngeal nonkeratinizing squamous cell carcinoma: characterization of a distinct phenotype.

We have recently shown that HPV-positive tonsillar carcinoma in young patients exhibits nonkeratinizing basaloid morphology and a characteristic immunophenotype. The purpose of this study was to review a large number of cases of oropharyngeal carcinomas, in all age groups, and to identify tumors with nonkeratinizing morphology. Using polymerase chain reaction (PCR) the prevalence and type of HPV DNA was determined in representative cases and in a control group of conventional keratinizing squamous cell carcinomas. The tumors were further characterized with a panel of immunohistochemical stains. A total of 235 carcinomas were reviewed; 141 of the tonsils and 94 in the base of tongue. Ninety (36%) of the tonsillar and 30 (32%) of the base of tongue carcinomas were nonkeratinizing (NKCa) with basal cell features; the rest were classical keratinizing squamous cell carcinomas (KSCC). HPV DNA, particularly type 16, was identified in 10 (100%) of 10 of NKCA and in only 2 (20%) of 10 of KSCC (P = .0014). NKCas were strongly reactive to p16 antibodies while KSCC showed weak and focal reactivity. Higher Ki67 and lower p53 staining scores were observed in NKCa as compared to KSCC. It is concluded that NKCa of the tonsils and base of tongue is a distinct subtype of squamous cell carcinoma of the head and neck with high prevalence of HPV DNA and a characteristic immunophenotype.     

Robot assisted laparoscopic partial nephrectomy: initial experience

PURPOSE: Advances in laparoscopy have made laparoscopic partial nephrectomy a technically feasible procedure but it remains challenging to even experienced laparoscopists. We hypothesized that robotic assisted laparoscopic partial nephrectomy may make this procedure more efficacious than the standard laparoscopic approach. MATERIALS AND METHODS: Ten patients with a mean age of 58 years and mean tumor size of 2.0 cm underwent robotic assisted laparoscopic partial nephrectomy and another 10 with a mean age of 61 years and mean tumor size of 2.18 cm underwent laparoscopic partial nephrectomy, as performed by a team of 2 surgeons (MS and ST) between May 2002 and January 2004. Demographic data, intraoperative parameters and postoperative data were compared between the 2 groups. RESULTS: There were no significant differences in patient demographics between the 2 groups. Intraoperative data and postoperative outcomes were statistically similar. In the 10 patients who underwent robotic assisted laparoscopic partial nephrectomy there were 2 intraoperative complications. There was 1 conversion in the laparoscopic partial nephrectomy group. CONCLUSIONS: Robotic assisted laparoscopic partial nephrectomy is a safe and feasible procedure in patients with small exophytic masses. The robotic approach to laparoscopic partial nephrectomy does not offer any clinical advantage over conventional laparoscopic nephrectomy.     

Evaluation of a novel precision template-guided biopsy system for detecting prostate cancer

OBJECTIVE

To explore the ability of a novel transrectal ultrasonography (TRUS) device (TargetScan^TM, Envisioneering Medical Technologies, St. Louis MO) that creates a three‐dimensional map of the prostate and calculates an optimal biopsy scheme, to accurately sample the prostate and define the true extent of disease, as standard TRUS‐guided prostate biopsy relies on the operator to distribute the biopsy sites, often resulting in under‐ and oversampling regions of the gland.

PATIENTS AND METHODS

In a multicentre retrospective chart review evaluating patients who had a TargetScan prostate biopsy between January 2006 and June 2007, we determined the overall cancer detection rate in all patients and in subgroups based on prostate specific antigen level, digital rectal examination, and indication for biopsy. We assessed the pathological significance of cancer detected, defined as a Gleason score of ≥7, positive margins, extracapsular disease or >20% tumour volume in the prostatectomy specimen. We also evaluated the concordance in Gleason score between the biopsy and prostatectomy specimen.

RESULTS

Cancer was detected in 50 (35.7%) of the 140 patients biopsied, including 39 (47.6%) with no previous biopsies. Of 23 prostatectomy specimens, 20 (87%) had pathologically significant disease. The biopsy predicted the prostatectomy Gleason score in 12 patients (52%), overestimated in two (9%), underestimated in eight (35%), and biopsy Gleason score could not be assigned in one (4%).

CONCLUSIONS

Template‐guided biopsy potentially produces a higher cancer detection rate and more accurate assessment of grade. Prostatectomy specimens did not have a high rate of pathologically insignificant disease.     

Establishment of a minimally invasive program at a Veterans' Affairs Medical Center leads to improved care in colorectal cancer patients

Background

Despite significant advantages to patients, less than 5% of all colorectal surgeries for cancer are performed laparoscopically. A minimally invasive colorectal cancer program was created in our Veterans' Affairs hospital with the intent of increasing access and improving quality of patient care while maintaining patient safety and oncologic standards.

Methods

Sixty consecutive laparoscopic colorectal cancer resections and 60 age-matched open resections were identified. Our prospective database was queried for demographic, clinical outcomes, and oncologic data.

Results

Patients undergoing laparoscopic resections experienced a shorter hospital stay and a quicker return of bowel function. Both groups had similar intraoperative blood loss and surgical times. Laparoscopic resections achieved equivalent lymph node retrieval and resection completeness compared with open resections. Laparoscopic resections resulted in fewer wounds and fewer complications requiring reoperation.

Conclusions

Establishment of a minimally invasive colorectal cancer program in a Veterans Affairs Medical Center leads to increased access to laparoscopic colorectal resections and improved patient care while maintaining patient safety.     

Role of the renin-angiotensin system in the development of the ureteric bud and renal collecting system

Genetic, biochemical and physiological studies have demonstrated that the renin-angiotensin system (RAS) plays a fundamental role in kidney development. All of the components of the RAS are expressed in the metanephros. Mutations in the genes encoding components of the RAS in mice or pharmacological inhibition of RAS in animals or humans cause diverse congenital abnormalities of the kidney and lower urinary tract. The latter include renal vascular abnormalities, abnormal glomerulogenesis, renal papillary hypoplasia, hydronephrosis, aberrant UB budding, duplicated collecting system, and urinary concentrating defect. Thus, the actions of angiotensin (ANG) II during kidney development are pleiotropic both spatially and temporally. Whereas the role of ANG II in renovascular and glomerular development has received much attention, little is known about the potential role of ANG II and its receptors in the morphogenesis of the collecting system. In this review, we discuss recent genetic and functional evidence gathered from transgenic knockout mice and in vitro organ and cell culture implicating the RAS in the development of the ureteric bud and collecting ducts. A novel conceptual framework has emerged from this body of work which states that stroma-derived ANG II elicits activation of AT₁/AT₂ receptors expressed on the ureteric bud to stimulate branching morphogenesis as well as collecting duct elongation and papillogenesis.     

Effect of rimonabant on progression of atherosclerosis in patients with abdominal obesity and coronary artery disease: the STRADIVARIUS randomized controlled trial

Context  Abdominal obesity is associated with metabolic abnormalities and increased risk of atherosclerotic cardiovascular disease. However, no obesity management strategy has demonstrated the ability to slow progression of coronary disease. Objective  To determine whether weight loss and metabolic effects of the selective cannabinoid type 1 receptor antagonist rimonabant reduces progression of coronary disease in patients with abdominal obesity and the metabolic syndrome. Design, Setting, and Patients  Randomized, double-blinded, placebo-controlled, 2-group, parallel-group trial (enrollment December 2004-December 2005) comparing rimonabant with placebo in 839 patients at 112 centers in North America, Europe, and Australia. Interventions  Patients received dietary counseling, were randomized to receive rimonabant (20 mg daily) or matching placebo, and underwent coronary intravascular ultrasonography at baseline (n = 839) and study completion (n = 676). Main Outcome Measures  The primary efficacy parameter was change in percent atheroma volume (PAV); the secondary efficacy parameter was change in normalized total atheroma volume (TAV). Results  In the rimonabant vs placebo groups, PAV (95% confidence interval [CI]) increased 0.25% (–0.04% to 0.54%) vs 0.51% (0.22% to 0.80%) (P = .22), respectively, and TAV decreased 2.2 mm³ (–4.09 to –0.24) vs an increase of 0.88 mm³ (–1.03 to 2.79) (P = .03). In the rimonabant vs placebo groups, imputing results based on baseline characteristics for patients not completing the trial, PAV increased 0.25% (–0.04% to 0.55%) vs 0.57% (0.29% to 0.84%) (P = .13), and TAV decreased 1.95 mm³ (–3.8 to –0.10) vs an increase of 1.19 mm³ (–0.73 to 3.12) (P = .02). Rimonabant-treated patients had a larger reduction in body weight (4.3 kg [–5.1 to –3.5] vs 0.5 kg [–1.3 to 0.3]) and greater decrease in waist circumference (4.5 cm [–5.4 to –3.7] vs 1.0 cm [–1.9 to –0.2]) (P < .001 for both comparisons). In the rimonabant vs placebo groups, high-density lipoprotein cholesterol levels increased 5.8 mg/dL (4.9 to 6.8) (22.4%) vs 1.8 mg/dL (0.9 to 2.7) (6.9%) (P < .001), and median triglyceride levels decreased 24.8 mg/dL (–35.4 to –17.3) (20.5%) vs 8.9 mg/dL (–14.2 to –1.8) (6.2%) (P < .001). Rimonabant-treated patients had greater decreases in high-sensitivity C-reactive protein (1.3 mg/dL [–1.7 to –1.2] [50.3%] vs 0.9 mg/dL [–1.4 to –0.5] [30.9%]) and less increase in glycated hemoglobin levels (0.11% [0.02% to 0.20%] vs 0.40% [0.31% to 0.49%]) (P < .001 for both comparisons). Psychiatric adverse effects were more common in the rimonabant group (43.4% vs 28.4%, P < .001). Conclusions  After 18 months of treatment, the study failed to show an effect for rimonabant on disease progression for the primary end point (PAV) but showed a favorable effect on the secondary end point (TAV). Determining whether rimonabant is useful in management of coronary disease will require additional imaging and outcomes trials, which are currently under way. Trial Registration  clinicaltrials.gov Identifier: NCT00124332