Prostate cancer and microfluids

Microfluidic systems aim to detect sample matter quickly with high sensitivity and resolution, on a small scale. With its increased use in medicine, the field is showing significant promise in prostate cancer diagnosis and management due, in part, to its ability to offer point-of-care testing. This review highlights some of the research that has been undertaken in respect of prostate cancer and microfluidics. Firstly, this review considers the diagnosis of prostate cancer through use of microfluidic systems and analyses the detection of prostate specific antigen, proteins, and circulating tumor cells to highlight the scope of current advancements. Secondly, this review analyses progressions in the understanding of prostate cancer physiology and considers techniques used to aid treatment of prostate cancer, such as the creation of a micro-environment. Finally, this review highlights potential future roles of microfluidics in assisting prostate cancer, such as in exosomal analysis. In conclusion, this review shows the vast scope and application of microfluidic systems and how these systems will ensure advancements to future prostate cancer management.

Urological technology: where will we be in 20 years' time?

Since prehistoric times, our understanding of urology has rapidly expanded. Whilst primitive urologists began by using urine as a therapeutic substance, modern urologists may find themselves removing a kidney remotely by driving a robotic arm, with seven degrees of movement, while using image overlay-augmented reality. This review provides an insight into the potential status of urological technology in 20 years' time, assessed through an analysis of developments in imaging, diagnostics, robotics and further technologies. A particular emphasis is given to the promising fields of minimally invasive techniques, nanotechnology and tissue engineering, which likely hold the key to a new era for urology.

Hepatic portal venous gas: acute deterioration in an elderly patient

A 91-year-old female presented to the Emergency Department with a 10-day history of constipation and abdominal pain. Abdominal examination was normal and rectal examination showed faecal loading. A phosphate enema was given and the patient was admitted. Overnight, the patient’s GCS dropped from 15/15 to 3/15 and an arterial blood gas showed a lactate of 8 mmol/L (1.5 on admission). Abdomen remained soft throughout. A CT scan showed a large amount of free air and free fluid within the abdomen and pelvis, highly suspicious for perforation. Hepatic portal venous gas (HPVG) was visible, with portal venous air fluid levels noted. The patient was treated palliatively and died shortly thereafter. HPVG is a recognized but rarely identified radiological sign, which is a poor prognostic indicator, with most cases subsequently proving terminal, often due to subsequent bowel necrosis.

Re-treatment of chronic hepatitis C patients after relapse: efficacy of peginterferon-alpha-2a (40 kDa) and ribavirin

We conducted a randomized multinational study to determine whether 48 weeks of re-treatment with peginterferon-alpha-2a (40 kDa) plus ribavirin would induce a sustained virological response (SVR) in relapsed chronic hepatitis C patients. Patients who had previously relapsed during 24 weeks of untreated follow-up, after having achieved an end-of-treatment virological response with 24 weeks of peginterferon-alpha-2a (40 kDa)/ribavirin combination therapy, within a phase III trial, were studied. Although the recommended dosage was the same as that used at the end of the initial trial, adjustments were permitted. Data on serious adverse events, or adverse events that resulted in dose reductions or discontinuations, were collected. Following re-treatment, the overall SVR rate in the 64 patients was 55%. The SVR rates in patients infected with hepatitis C virus (HCV) genotype 1 and non-1 genotypes were 51% and 63%, respectively. Early (week 12) virological responses were seen in 39 patients (61%) and were predictive of an SVR. Re-treatment was well tolerated. The most frequent adverse events recorded were fatigue (5%) and abdominal pain (3%). Dosages of peginterferon-alpha-2a (40 kDa) and/or ribavirin were modified because of adverse events in 3% and 13% of patients, and because of laboratory abnormalities in 23% and 5% of patients, respectively. Thus, a 48-week course of peginterferon-alpha-2a (40 kDa) plus ribavirin induces an SVR in 55% of patients who relapsed during follow-up after 24 weeks of combination therapy. Physicians should not hesitate to offer re-treatment to patients who relapse after an initial, 24-week course of combination therapy, or who have prematurely stopped treatment because, for example, of laboratory abnormalities.

Cost-effectiveness of combination peginterferon alpha-2a and ribavirin compared with interferon alpha-2b and ribavirin in patients with chronic hepatitis C

BACKGROUND

Sustained virological response (SVR) is the primary objective in the treatment of chronic hepatitis C (CHC). Results from a recent clinical trial of patients with previously untreated CHC demonstrate that the combination of peginterferon alpha-2a and ribavirin produces a greater SVR than interferon alpha-2b and ribavirin combination therapy. However, the cost-effectiveness of peginterferon alpha-2a plus ribavirin in the U.S. setting has not been investigated.

METHODS

A Markov model was developed to investigate cost-effectiveness in patients with CHC using genotype to guide treatment duration. SVR and disease progression parameters were derived from the clinical trials and epidemiologic studies. The impact of treatment on life expectancy and costs were projected for a lifetime. Patients who had an SVR were assumed to remain virus-free for the rest of their lives. In genotype 1 patients, the SVRs were 46% for peginterferon alpha-2a plus ribavirin and 36% for interferon alpha-2b plus ribavirin. In genotype 2/3 patients, the SVRs were 76% for peginterferon alpha-2a plus ribavirin and 61% for interferon alpha-2b plus ribavirin. Quality of life and costs were based on estimates from the literature. All costs were based on published U.S. medical care costs and were adjusted to 2003 U.S. dollars. Costs and benefits beyond the first year were discounted at 3%.

RESULTS

In genotype 1, peginterferon alpha-2a plus ribavirin increases quality-adjusted life expectancy (QALY) by 0.70 yr compared to interferon alpha-2b plus ribavirin, producing a cost-effectiveness ratio of $2,600 per QALY gained. In genotype 2/3 patients, peginterferon alpha-2a plus ribavirin increases QALY by 1.05 yr in comparison to interferon alpha-2b plus ribavirin. Peginterferon alpha-2a combination therapy in patients with HCV genotype 2 or 3 is dominant (more effective and cost saving) compared to interferon alpha-2b plus ribavirin. Results weighted by genotype prevalence (75% genotype 1; 25% genotype 2 or 3) also show that peginterferon alpha-2a plus ribavirin is dominant. Peginterferon alpha-2a and ribavirin remained cost-effective (below $16,500 per QALY gained) under sensitivity analyses on key clinical and cost parameters.

CONCLUSION

Peginterferon alpha-2a in combination with ribavirin with duration of therapy based on genotype, is cost-effective compared with conventional interferon alpha-2b in combination with ribavirin when given to treatment-naïve adults with CHC.

Recombinant factor VIIa corrects prothrombin time in cirrhotic patients: a preliminary study

BACKGROUND & AIMS

Cirrhotic patients with a prolonged prothrombin time (PT) are known to have low levels of factor VII. Because the current modalities to correct this problem are not ideal, recombinant factor VIIa (rFVIIa) may be useful in correcting the prolonged PT observed in the coagulopathy of cirrhosis. The aim of this study was to evaluate the effectiveness of rFVIIa in nonbleeding volunteer patients with the coagulopathy of cirrhosis.

METHODS

A preliminary, single-center, dose-escalation trial was performed. Cirrhotic patients with a PT of > 2 seconds above the upper limit of the reference value received an intramuscular injection of vitamin K. Ten patients whose PT did not correct to within 2 seconds above the control of the upper limit of the reference value were given three successive dosages of rFVIIa (5, 20, and 80 micrograms/kg) during a 3-week period.

RESULTS

The mean PT transiently corrected to normal in all three dosage groups. No adverse effects were noted. There was no evidence of the induction of disseminated intravascular coagulation.

CONCLUSIONS

This preliminary trial shows rFVIIa to be effective in transiently reversing the prolonged PT in a select group of nonbleeding cirrhotic patients. These preliminary observations support conducting a large-scale efficacy trial.

Laparoscopic evaluation of liver disease in chronic renal failure prior to renal transplantation

BACKGROUND

Diagnostic laparoscopy with liver biopsy has been shown to be safe and effective in the evaluation of patients with chronic liver disease. Patients with end-stage renal disease may be more prone to bleeding complications secondary to liver biopsy as a result of multiple factors directly related to their underlying renal condition.

METHODS AND PATIENTS

From January 1994 to June 1996, 16 patients with end-stage renal disease and hepatic dysfunction (6 women and 10 men) underwent diagnostic laparoscopy with liver biopsy prior to renal transplantation at the University of Miami School of Medicine. Laparoscopy was performed using a 5 mm video laparoscope with a left paramedian approach. The mean patient age was 46 years. Fourteen patients had chronic hepatitis C with a reactive anti-HCV by ELISA; one patient had chronic hepatitis B with reactive HBsAg, and one patient was co-infected with both hepatitis B and C viruses.

RESULTS

Two patients developed hypotension related to the procedure and one patient developed an intra-abdominal hemorrhage 5 days after laparoscopy that did not require surgical intervention. Biopsy findings were as follows: 13 patients had mild chronic hepatitis; 2 patients had chronic hepatitis with bridging fibrosis; and 1 patient was cirrhotic. Prior kidney transplantation or peritoneal dialysis did not preclude the performance of laparoscopy.

CONCLUSION

Diagnostic laparoscopy can be safety performed in patients with end-stage renal disease with acceptable morbidity and mortality.

Portal hypertensive gastropathy

PHG is a common condition that is now recognized as a complication of advanced liver disease. This vascular disorder has been shown to be a significant cause of upper gastrointestinal bleeding in patients with portal hypertension. Although its pathogenesis is directly related to portal hypertension, the exact mechanisms remain to be determined. Decreased mucosal blood flow and passive congestion of the gastric submucosal layer appear to play a role in the development of PHG. Its endoscopic appearance is characterized by a "snake skin" mucosal pattern with gastric biopsies revealing vascular congestion. PHG may present as either acute or chronic gastrointestinal bleeding and has been noted to worsen after endoscopic sclerotherapy and band ligation therapy for esophageal varices. Unlike variceal bleeding, this condition cannot be treated with either sclerotherapy or band ligation. Effective treatment requires a reduction in portal pressure. This can be accomplished through the use of beta-blockers, radiographic or surgical shunting, or liver transplantation.

The role of laparoscopy in the diagnosis of cirrhosis

BACKGROUND

A definitive diagnosis of cirrhosis is important in the prognosis and management of patients with chronic liver disease. The diagnosis of cirrhosis is made either by histologic examination of a biopsy specimen or upon visualization of a diffusely nodular and firm surface of the liver at laparotomy or laparoscopy. A liver biopsy, however, may not demonstrate the histologic features of cirrhosis in some cirrhotic patients. Our goal in this study was to compare the accuracy of liver descriptions made during laparoscopy with liver histology found by laparoscopic biopsy in patients with chronic liver disease.

METHODS

A retrospective review of paired laparoscopy and histology reports was performed on 434 consecutive patients who underwent laparoscopy between 1992 and 1994. (M:F ratio, 1.3:1; mean age, 48 +/- 14 years).

ETIOLOGY

52% hepatitis C, 8% hepatitis B, 8% fatty liver, 4% primary biliary cirrhosis, 3% autoimmune hepatitis, and 25% miscellaneous (cancer patients were excluded).

RESULTS

One hundred sixty-nine patients had laparoscopic evidence of cirrhosis; 115 were confirmed by histology, representing a 32% sampling error. Two of 265 patients with histologic evidence of cirrhosis (0.8%) had no macroscopic evidence of cirrhosis at laparoscopy.

CONCLUSIONS

(1) There was a 32% histologic sampling error among patients documented to have cirrhosis by laparoscopy. (2) Using laparoscopy as a gold standard, the sensitivity of liver biopsy was 68% and the specificity was 99%.

Hepatitis C virus in alcoholic patients with and without clinically apparent liver disease

A high prevalence of antibodies to the hepatitis C virus (anti-HCV) has been demonstrated among patients with alcoholic liver disease, whereas the prevalence of HCV viremia in these patients remains uncertain. The aims of this study were to determine the prevalence of anti-HCV in alcoholic patients both with and without clinically apparent liver disease and to determine the presence of HCV RNA in those patients who tested positive for anti-HCV by RIBA II (Chiron Corporation, Emeryville, CA). One hundred male patients consecutively admitted to an alcoholic rehabilitation program were included. Group 1 was comprised of 40 patients with clinically apparent liver disease. Group 2 was comprised of 60 patients without clinically apparent liver disease. Anti-HCV was performed by a second-generation ELISA assay and confirmed by RIBA II. HCV RNA was performed by Quantiplex assay (Chiron Corporation) and a nested reverse transcriptase-polymerase chain reaction. No significant differences were found between the two groups with regards to age, quantity and duration of alcohol intake, or accepted risk factors for HCV. The overall prevalence of anti-HCV in our patients was 23%, with 43% of these in group 1 and 10% in group 2. HCV RNA tested positive in 94% of the anti-HCV-positive patients in group 1 and in 67% of the anti-HCV-positive patients in group 2. These data suggest that HCV infection is an important cofactor in the pathogenesis of liver disease among alcoholic patients.

Standard biopsy forceps versus large-capacity forceps with and without needle

Endoscopic biopsy forceps vary in size and design. The purpose of this prospective randomized study was to compare the quality and quantity of gastric tissue obtained by needle and non-needle versions of standard biopsy forceps and newly designed large capacity forceps. Fifty consecutive patients who underwent endoscopy with gastric biopsy forceps were enrolled in the study. There was no significant difference in the presence of crush artifact between the two forceps, both with and without the presence of a needle. Both needle and non-needle versions of the large capacity biopsy forceps were found to obtain significantly larger sized specimens (p = 0.02) than needle and non-needle versions of the standard biopsy forceps. Overall, there was no significant difference in the depth of specimen obtained when comparing the large capacity forceps to standard forceps. Needle versions of each forceps were found to obtain significantly deeper biopsies than non-needle versions of each forceps. In conclusion, our study found that large capacity forceps obtained larger specimens than standard biopsy forceps. Further clinical trials with a larger study population need to be undertaken to determine the impact of these findings on the determination of diagnoses.

Parasitic causes of pancreatic and biliary tract disease: a growing concern in a highly mobile population

A leading cause of biliary tract disease and pancreatitis worldwide is parasitic disease. In the United States, increased global travel and the AIDS epidemic has led to a rise in the frequency of parasitic disease. Biliary disease and pancreatic disease secondary to parasitic infestation is relatively new in this country, with the first case being described in 1977. These diseases are no longer the exclusive realm of infectious disease specialists and require general practitioners and gastroenterologists to be well versed in the spectrum of parasitic pancreatic and biliary disease.