The Observatory

May 23, 2017

Lung cancer in America

158,080
Is the approximate number of Americans who died from lung cancer in 2016.

27 percent
Is the proportion of all cancer deaths attributed to lung cancer in the U.S. in 2016.

51.7
Per 100,000 is the age-adjusted death rate from lung cancer for American men.

34.7
Per 100,000 is the age-adjusted death rate from lung cancer for American women.

415,000
Is the approximate number of Americans living today who have been diagnosed with lung cancer at some point in their life.

83 percent
Is the proportion of Americans living with lung cancer who are age 60 or older (2013 figures).

17.7 percent
Is the five-year survival rate for lung cancer overall.

55 percent
Is the five-year survival rate for lung cancer that is diagnosed when it is still localized.

>50%
Is the proportion of lung cancer patients who die within one year of diagnosis.

~80%
Is the proportion of small cell and non-small cell lung cancer in women in which smoking is a contributing factor.

~90%
Is the proportion of small cell and non-small cell lung cancer in men in which smoking is a contributing factor.

Source:American Lung Association “Lung Cancer Fact Sheet.” http://www.lung.org/lung-health-and-diseases/lung-disease-lookup/lung-cancer/resource-library/lung-cancer-fact-sheet.html

Zika Virus

Researchers identify potential ZIKV target. New research provides insights into why infection with ZIKV after birth generally causes only mild symptoms, whereas devastating fetal malformations can develop when infection occurs during pregnancy.

Healthy people are protected by antiviral factors of the innate immune system. Investigators have now shown that reducing levels of one antiviral factor called interferon-induced transmembrane protein 3 (IFITM3) makes cultured cells highly sensitive to ZIKV infection.

The research team found that IFITM3 normally stops multiplication of the virus in human cells at an early step, preventing the infected cells from “implosive” cell death. Therefore, drugs that block this cell death pathway might be helpful for preventing the effects of ZIKV infection during pregnancy.

“We describe a striking succession of events that may lead to the death of cells infected with Zika virus. Hopefully, the cells are equipped with antiviral gatekeepers that allow the host to control the infection,” says Dr. Olivier Schwartz of Institut Pasteur, senior author of The EMBO Journal study.

A speedy, sensitive, and low-cost detection test for ZIKV. A fast, highly sensitive, and inexpensive new test not only detects ZIKV in mosquitoes and human bodily fluids, but can also distinguish between African and Asian strains. That could improve efforts to more effectively track the virus’s spread.

Colorado State University researcher Nunya Chotiwan and colleagues devised an assay to directly detect ZIKV from mosquitoes and several different types of unprocessed clinical samples (including human blood, saliva, and semen). They amplified ZIKV genomes using a molecular technique called loop-mediated isothermal amplification (LAMP), an approach that proved comparably sensitive to the current gold-standard detection method, qRT-PCR. Unlike qRT-PCR, however, LAMP does not require costly reagents. Importantly, LAMP did not yield false-positives for closely-related pathogens such as dengue virus and chikungunya virus.

The researchers validated the LAMP test using virus artificially spiked into materials obtained from healthy individuals, and also in clinical specimens collected from confirmed cases of ZIKV infection. LAMP was also sufficiently sensitive to identify one single infected mosquito from a collection pool of 50 uninfected insects. The authors say that LAMP’s minimal processing requirements and accelerated turnaround time will be valuable for ZIKV surveillance and control.

New Studies

Displaying EHR lab test costs doesn’t deter doctors from ordering them. Patients are stuck for a blood draw almost every day they are admitted to a hospital. Lab tests are one of the most common orders placed by doctors, but research indicates that nearly one-third of those tests are not needed.

Hospitals nationwide are seeking ways to use price transparency—displaying the price of lab tests at the time when doctors are placing the order—to nudge doctors to consider whether the benefits are worth the cost. Results of a new study, however, show that simply displaying the Medicare allowable fees did not have an overall impact on how clinicians ordered the tests.

In the new study, researchers randomly assigned 60 groups of inpatient lab tests to either display Medicare allowable fees in the patient’s EHR (intervention arm), or not (control arm). The randomized clinical trial was conducted at three hospitals within the University of Pennsylvania Health System over a one-year period and compared changes in the number of tests ordered per patient per day, and associated fees, for more than 98,000 patients (totaling over 142,000 admissions).

Results of the study showed that in the year prior to the study, when cost information was not displayed, the average number of tests and associated fees ordered per patient per day was 2.31 tests totaling $27.77 in the control group, and 3.93 tests totaling $37.84 in the intervention group. After the intervention, when cost information was displayed for the intervention group, researchers noted the average number of tests and associated fees ordered per patient per day did not change significantly: they were 2.34 tests totaling $27.59 in the control group, and 4.01 tests totaling $38.85 in the intervention group.

Though the study found no overall effect, the authors noted important findings in specific patient groups that have implications for how to improve price transparency in the future. For example, there was a slight decrease in test ordering for patients admitted to the ICU—an environment in which doctors are making rapid decisions and may be more exposed to the price transparency intervention. The authors also found that the most expensive tests were ordered less and the cheaper tests were ordered more, suggesting that future interventions might be more successful if they are better designed to framed relative pricing.

Saliva test predicts prolonged concussion symptoms in children. Although most of the three million concussions diagnosed in the U.S. each year occur in children, the bulk of clinical guidelines are based on adults. Because of this, pediatricians are limited in how accurately they can advise families about how long a child may suffer symptoms such as headaches, fatigue, and trouble concentrating that can interfere with school and other activities.

New research presented at the 2017 Pediatric Academic Societies Meeting last month, however, suggests a simple saliva test may yield more answers. Investigators from Penn State College of Medicine presented an abstract of the study “Peripheral microRNA patterns predict prolonged concussion symptoms in pediatric patients” at the conference.

Micro ribonucleic acids (miRNAs) are genetic molecules, chiefly found within cells, that help regulate protein production. Previous studies have found altered miRNA levels in the saliva of children with mild concussions. This mirrored similar miRNA changes in cerebrospinal fluid of patients with severe brain injury.

The researchers studied 50 children between the ages of 7 and 18 years with mild traumatic brain injury. Spit samples were collected and tested for miRNA levels. In addition, concussion symptoms were evaluated through parent and child Sports Concussion Assessment Tool (SCAT-3) surveys, a standardized tool commonly used to evaluate injured children for concussion and to guide clinical decision-making. The surveys were taken within 14 days of injury and again four weeks post-concussion. The 29 children with prolonged concussion symptoms had higher scores for headaches, fatigue, and difficulties concentrating.

Steven Hicks, MD, PhD, FAAP, lead study author, says the salivary miRNA levels were significantly more effective than evaluations using SCAT-3 survey in predicting which children would continue to experience headaches, fatigue, concentration difficulties, and other concussion symptoms that lasted longer than four weeks. Results showed the standard survey to be less than 70 percent accurate in identifying children who would have prolonged concussion symptoms, he says. In comparison, he reports, miRNA in saliva correctly predicted whether concussion symptoms would remain present for at least a month nearly 90 percent of the time.

“We believe that saliva-based RNA testing holds great promise as an accurate and non-invasive method for evaluating pediatric concussions and giving patients and families a more solid prognosis,” Dr. Hicks says.

Cancer

Women should continue cervical cancer screening as they approach age 65. Cervical cancer is often thought of as a disease that primarily affects young women. Because of this, many older women fail to keep up with appropriate screening as they age. While current guidelines indicate that screening can be stopped for average-risk patients after age 65, many women lack the appropriate amount of screening history to accurately assess their risk.

A new study in the American Journal of Preventive Medicine found that incidence rates of cervical cancer do not begin to decline until 85 years of age among women without a hysterectomy and that women over 65 who have not been recently screened may benefit from continued surveillance.

“An older woman who has not had her cervix surgically removed has the same or even higher risk of developing cervical cancer compared to a younger woman,” says lead investigator Mary C. White, ScD, Chief of the Epidemiology and Applied Research Branch, Division of Cancer Prevention and Control, Centers for Disease Control and Prevention (CDC). “Women who have not had a hysterectomy need to continue to be screened until age 65, and possibly later if they have not been screened for many years or are at special risk, consistent with current U.S. Preventive Services Task Force recommendations.”

In 2013, one-fifth of cervical cancer cases and one-third of cervical cancer deaths occurred among women 65 years of age and older. Current recommendations say that screening can be stopped at age 65 if an adequate testing history indicates consistently negative results. Three consecutive negative cytology results or two consecutive negative co-test results within the last 10 years, with the most recent test within the last five years, are considered sufficient reason to stop screening average-risk women after age 65.

Using data from the 2013 and 2015 National Health Interview Survey, investigators looked at the use of screening tests and rates of cervical cancer for women 65 and older. The data revealed that many women approaching the “stopping” age of 65 were not getting sufficient screening. Researchers established that the proportion of women not recently screened increases with age. While only 12 percent of women in their 40s had no recent screening history, that number progressively increased for women in their 50s and 60s. Nearly 850,000 women aged 61 to 65 years had not been screened within the last five years.

Higher prostate cancer risks for black men may warrant new approach to screening. A new study indicates that higher prostate cancer death rates among black men in the United States may be due to a higher risk of developing preclinical prostate cancer as well as a higher risk of that cancer progressing more quickly to advanced stages. Published early online in CANCER, the study suggests that screening policies may need to be tailored to the higher-risk status of this population.

Among black men in the U.S., the incidence of prostate cancer is 60 percent higher than that of white men, and their mortality rate from prostate cancer is more than twice as high. To understand why, researchers used three models of prostate cancer incidence and prostate specific antigen (PSA) screening in the U.S. to estimate disease onset and progression based on prostate cancer data from 1975 to 2000 reported by the Surveillance, Epidemiology, and End Results program of the National Cancer Institute.

The investigators estimated that 30 percent to 43 percent of black men develop preclinical prostate cancer by age 85, a risk that is 28 percent to 56 percent higher than that among men of any race.

Among men with preclinical disease, black men have a similar risk of being diagnosed (35 percent to 49 percent) compared with the general population (32 percent to 44 percent) in the absence of screening. Their risk of progression to advanced disease by the time they’re diagnosed is 44 percent to 75 percent higher than in the general population, however (a 12 to 13 percent risk in black men versus a seven to nine percent risk in the general population).

“We found that the interval from getting preclinical cancer to being diagnosed is long—10 years or more on average—and is similar in black and white men. But during that interval, cancers in black men tend to progress faster,” says Ruth Etzioni, PhD, a senior study author. “What this means is that in developing screening policies for black men, it will be important to consider beginning screening them at an earlier age and potentially screening them more frequently than would be recommended by general population guidelines.”