Simplifying Pulmonary Embolism Diagnosis

SOURCE: van der Hulle, et al. Lancet 2017;390:289-297.

The consequences of missing pulmonary embolism (PE) are grave, and numerous prediction methods have evolved to refine clinicians’ ability to properly identify PE. Unfortunately, increasing zeal for early identification of PE also has led to increased proportions of screened patients turning out to be PE-negative. Indeed, diagnostic imaging with CT pulmonary angiography (CTPA), the test of choice for PE confirmation, is negative in as many as 90% of patients suspected of PE.

CTPA is not without risk, both the immediate risk of contrast medium and concerns about long-term radiation consequences. You may be surprised to learn that the radiation of CTPA is equivalent to literally 1,500 chest X-rays, so it is not to be undertaken lightly.

A new decision rule considered by van der Hulle et al includes three primary items: clinical signs of deep vein thrombosis, hemoptysis, and clinical suspicion that PE is the most likely diagnosis. When coupled with D-dimer thresholds, this decision rule appears to reduce the frequency with which unnecessary CTPA is required. For instance, when none of the three primary items are present and d-Dimer is < 1,000 ng/mL, or when one to two primary items exist but D-dimer is < 500 ng/mL, PE is essentially excluded, and CTPA is not necessary. Compared with the widely used Wells’ rule, employment of this decision rule resulted in a significant diminution of the need for CTPA.

This large clinical trial (n = 3,465) of patients with potential PE, all of whom underwent CTPA to confirm the exclusionary capacity of the new diagnostic scheme, suggests that we may be able to be more efficient in limiting the number of patients who undergo CTPA.

Observation vs. Surgery for Early Prostate Cancer

SOURCE: Wilt TJ, et al. N Engl J Med 2017;377:132-142.

The saga of recommendations about screening for prostate cancer continues to evolve. Whereas in 2012, the U.S. Preventive Services Task Force (USPSTF) gave a “two thumbs down” rating to prostate cancer screening, its 2017 position has softened. Although the strength of the recommendation is only level C (at least moderate certainty that net benefit is small), the USPSTF has indicated that for men 55-69 years of age, clinicians should provide an individualized approach after informing the patient about the risks and benefits. For men ≥ 70 years of age, the USPSTF does not recommend screening.

It’s not clear whether you will find results of a very long-term 2017 prostate cancer follow-up study consonant with the USPSTF recommendations. Wilt et al reported on the 20-year follow-up of men with early prostate cancer treated with surgery or observation. As was noted on the first outcomes report of this same population in 2012, no clear advantage for surgery emerged. That is, neither all-cause mortality nor prostate cancer-related mortality was statistically significantly lower in men who underwent surgical intervention than in men who were randomized to observation.

Since there were many more burdensome adverse effects associated with surgical intervention (primarily erectile dysfunction and urinary incontinence), the choice of treatment does not seem unclear to me were I suffering early prostate cancer, and especially low Gleason score disease. Nonetheless, keeping in step with the USPSTF, clinicians are now encouraged to inform men 55-69 years of age about the relative risks and benefits of screening, and to individualize based on their informed decision.

Tamsulosin for Lower Urinary Tract Symptoms in Women

SOURCE: Zhang HL, et al. Int J Impot Res 2017;29:148-156.

The umbrella term “lower urinary tract symptoms” (LUTS) includes symptoms such as difficulty starting stream, dribbling, incontinence, urgency, and incomplete emptying. In men, the most common source of LUTS is benign prostatic hyperplasia. Alpha-blockers (e.g., tamsulosin, alfuzosin) are employed commonly to treat LUTS in men, based on their capacity to decrease prostatic smooth muscle tone as well as relax the musculature of the bladder neck, which also is rich in alpha-receptors. Individual trials of alpha-blockers in women also have demonstrated improvements in LUTS.

Zhang et al performed a meta-analysis of trials of the efficacy of tamsulosin in women with LUTS (n = 764). They found positive effects on voiding symptoms and quality of life scores. Whereas the typical first-line treatment for women with overactive bladder usually is anticholinergics or beta-3 agonist treatment, these data also showed a favorable effect of tamsulosin on the Overactive Bladder Questionnaire score. Clinicians who are familiar with prescribing tamsulosin probably will recognize that it is generally well tolerated in men.

However, long-term safety trials in women have not been conducted. Decades of use of alpha-blockers to treat hypertension in both genders as well as the long-term data of benignity in men reassure clinicians that tamsulosin may be a valuable (though off-label) treatment for LUTS in women.