Lung disease patients may no longer require biopsies for diagnosis

People who are suspected to have the lung
disease idiopathic pulmonary fibrosis may not
have to undergo biopsies, as clinical and
radiological results should provide a confident
diagnosis, according to a new study published in
The Lancet Respiratory Medicine journal.
There is no cure for IPF and most people will only
survive for 3 to 5 years following diagnosis. The
disease causes scarring of the lungs, which
worsens over time, until the lungs are unable to
supply the required levels of oxygen to the rest of
the body,
About 50,000 new cases of idiopathic pulmonary
fibrosis (IPF) are diagnosed in the US each year.
The mortality rates associated with IPF are
comparable to the rates of death from breast
cancer, as the disease kills 40,000 Americans
each year. Studies also suggest that IPF is
becoming more common.
High resolution computed tomography (HRCT) is
used to identify IPF, as the disease often leaves a
characteristic "honeycomb" scarring pattern,
known as usual interstitial pneumonia (UIP).
Currently, when IPF is suspected in a patient but
there is no sign of the UIP pattern, international
guidelines recommend that a biopsy be taken to
confirm the diagnosis.
But taking a biopsy from the lung is a risky
procedure. As Prof. Ganesh Raghu, who led the
research behind the new study, explains:
"Surgical lung biopsy is associated with
substantial risks and many patients are too
elderly, sick, and/or have comorbid conditions to
tolerate the invasive procedure."
"A confident diagnosis of IPF is needed to ensure
that patients are well informed of the poor
prognosis associated with IPF, are treated with
the most appropriate therapies, consider
participation in clinical trials of new therapies,
and to identify those most suitable for lung
transplantation."
Are biopsies always necessary ?
Prof. Raghu and team wanted to see if IPF could
be accurately diagnosed in patients who do not
exhibit UIP from HRCT scans, without the need
for a biopsy.
To test this, the team showed expert radiologists
and pathologists HRCT scans of 315 patients who
had previously been suspected of IPF - but who
presented with little or no visible honeycombing.
The experts were able to diagnose with 94%
accuracy the patients who had IPF but whose
scans exhibited little or no scarring. The
researchers knew that the experts' diagnoses
were accurate, as they also had access to results
of the patients' biopsies.
Prof. Raghu says: