A new study from Tel Aviv University and Rabin Medical Center, Israel, researchers proposes that screening heavy smokers admitted to the hospital with community-acquired pneumonia could facilitate the early diagnosis of lung cancer and thereby reduce the incidence of mortality.

Heavy smokers who are diagnosed with pneumonia are one of the highest lung cancer risk groups – and therefore should be considered for early screening by chest-computer tomography.

The research was led by Medical Director (MD) of TAU’s Sackler Faculty of Medicine and Rabin Medical Center, Dr. Daniel Shepshelovich, and was recently published in the American Journal of Medicine.

“Lung cancer is truly aggressive,” said Shepshelovich. “The only chance of recuperation is if it’s caught before it begins to cause any symptoms at all. The idea is to find the tumor well in advance. Previous studies have shown that a low-dose radiation Computed Tomography (CT) scan conducted once a year on heavy smokers has the potential to lower lung cancer mortality rates. But this requires huge resources, and we still don’t know how it will perform in real-world conditions, outside of strictly conducted clinical trials.

“We want to develop a more realistic and cost-effective strategy targeting a particularly high-risk population,” he said.

Shepshelovich and his team examined the files of 381 admissions of heavy smokers with community-acquired pneumonia – a form of pneumonia contracted by a person with little contact with the health care system – at Rabin Medical Center between 2007-2011. They reviewed every patient’s medical file for patient demographics, smoking history, lung cancer risk factors and the anatomical location of the pneumonia. The data was then crosschecked with the database at Israel’s National Cancer Registry for new diagnoses of cancer.

The researchers found that out of 381 admissions of heavy smokers with pneumonia, 31 to nine percent, a figure that surprised the researchers – were diagnosed with lung cancer within a year of being hospitalized. Lung cancer incidence was found to be significantly higher in patients admitted with upper lobe pneumonia (23.8 per cent). They also found that the lung cancer was located in the lobe affected by pneumonia in 75.8 per cent of cases.

“We discovered that smokers hospitalized with pneumonia are diagnosed with cancer after the infection because often the cancer masquerades as pneumonia, physically obstructing the airway and creating such an infection,” said Dr. Shepshelovich. “Considering that only 0.5 to one per cent of smokers without pneumonia have a chance of being diagnosed with lung cancer every year, the fact that nine per cent of our study group developed lung cancer is alarming.”

Extending the lives of cancer patients

“The current diagnostic methods in place – chest X-rays, sputum cytology – sometimes find the cancerous tumors, but they do not change mortality rates,” Shepshelovich said. “In other words, people are aware that they have cancer for longer periods of time, but do not recover. This is not a solution.

“Smokers admitted to the hospital with pneumonia should be considered for chest computer tomography,” he continued. “Only 15 percent of lung cancer cases are detected at an early stage. We want to increase that number in order to reduce mortality or, at the very least, extend lives.”

The researchers are currently considering a larger nationwide retrospective study on the subject.

Meanwhile, a new report says the effects of cancer screening on overall mortality overstated.

Experts in a report published in The BMJ argue there is insufficient evidence to claim cancer screening saves lives and call for future studies to assess the impact of cancer screening on overall mortality rather than disease-specific mortality alone.

Researchers claim studies have never shown cancer screening can reduce overall mortality.

Screening tests are available for a number of cancers, including breast, cervical, colorectal, lung, prostate and ovarian cancers.

Numerous studies have suggested cancer screening can reduce disease-specific mortality risk. A study reported by Medical News Today last month, for example, claimed ovarian cancer screening can reduce long-term mortality from the disease by 20 per cent.

But what about the effect of cancer screening on overall mortality?

According to Vinay Prasad, assistant professor at Oregon Health & Science University, United States, and colleagues, despite most studies finding a reduction in disease-specific mortality with cancer screening, few have shown reductions in overall mortality, and some have even found an increase in overall mortality.

Furthermore, the authors note that in cases where cancer screening was associated with falls in both disease-specific and overall mortality, the effect was still stronger for disease-specific mortality.