By Louis Kuritzky, MD
Risk of Adenocarcinoma in Barrett’s Esophagus
Although surveillance of Barrett’s esophagus (BES) for early detection of esophageal adenocarcinoma (E-CA) has become routine, the cost efficacy of this intervention is only scantily described.
Population data from Northern Ireland include all incident cancers. Murray and colleagues identified all subjects who had undergone esophageal biopsies with a diagnosis of BES between 1993 and 1999 and followed them up until 2000 identifying the number of subjects who were ultimately diagnosed with E-CA. Subjects who were diagnosed with E-CA within 6 months of the initial biopsy were not included in the data analysis.
Of 15,670 esophageal biopsies, almost 3000 met criteria for BES. In a follow-up period of 3.7 years (range, 1-8 years) 29 E-CA cases were identified. The mean yearly rate for E-CA was 0.26%, and 2.5 times higher in men than women. Risk was greatest in men older than 70 with specialized intestinal metaplasia found at esophageal biopsy, in whom the annual incidence was > 1%. Murray et al comment that when E-CA annual risk is 1%, surveillance may be cost-effective but that based upon these data, restricting surveillance to only the "high-risk" population would miss two-thirds of the incident cases of cancer. Our knowledge about the optimum schedule for BES surveillance remains incomplete.
Murray L, et al. BMJ(USA). 2003;3: 534-535.
Long-Term Effect of Doxazosin, Finasteride, and Combination for BPH
Benign prostatic hyperplasia (BPH) is commonly treated with alpha blockers such as doxazosin (DOX), alpha reductase inhibitors such as finasteride (FIN), or both. Long-term trials of DOX and FIN in combination have not been previously available to allow clinicians to compare the effect of alpha blockers, alpha reductase inhibitors, or both upon BPH symptoms. In addition to the value of symptom control, long-term treatments that reduce the need for surgical intervention are desired by clinicians and patients alike. Previous trials of alpha reductase inhibitors alone have indicated success in reducing the need for surgical intervention and the frequency of acute urinary retention.
Approximately 3000 men with symptomatic BPH who had not previously undergone surgical intervention, and whose PSA was < 10, were randomized to placebo, DOX, FIN, or DOX + FIN. The primary outcome was the first occurrence of a meaningful increase in the AUA symptom score (4 points or greater on a scale of 30).
Compared to placebo, both FIN and DOX had a statistically significant effect on the AUA symptom score (34-39% risk reduction). For this same end point, the benefit of combination therapy (DOX + FIN) was significantly greater than either agent alone. The risk of required surgical intervention or acute urinary retention was significantly reduced by FIN and DOX + FIN, but not DOX alone. Clinicians now have multiple logical options for long-term treatment of BPH.
McConnell JD, et al. N Engl J Med. 2003;349:2387-2398.
Once Daily Valacyclovir to Reduce Herpes Transmission
Among genital herpes virus (HSV-2) discordant couples, couples in whom one partner is HSV-2 infected and the other has not been, several strategies have been used to reduce likelihood of transmission to the uninfected partner. None of the strategies, save abstinence, can provide perfect assurance that HSV-2 transmission will not occur.
Asymptomatic persons shed HSV-2 and place their sexual partners at risk of transmission even during asymptomatic periods. It has been reported that subclinical viral shedding is the primary source of HSV-2 transmission. Antiviral treatment can reduce both the amount of time subclinical viral shedding occurs and the intensity with which virus is shed.
HSV-2 discordant monogamous couples (n = 743) were randomized to 500 mg valacyclovir QD (VAL) vs placebo for 8 months.
Only 4 of 743 susceptible partners on VAL developed symptomatic infection during the study period, compared with 16 placebo recipients (hazard ratio = .25). Similarly, seroconversion was found in 14 of 743 VAL-treated susceptibles, vs 27 of 741 on placebo. Placebo-treated patients excreted HSV-2 on 10.8% of days, compared with 2.9% of days with VAL treatment. Once-daily VAL can reduce, but not eliminate, HSV-2 transmission.
Corey L, et al. N Engl J Med. 2004;350(1):11-20.
Dr. Kuritzky, Clinical Assistant Professor, University of Florida, Gainesville, is Associate Editor of Internal Medicine Alert.