A group of clinician-reseachers with expertise in lung diseases suggest in a commentary that people with both idiopathic pulmonary fibrosis (IPF) and lung cancer are best managed with a goal of “first, do no harm.”

This means that “aggressive diagnostic and therapeutic interventions should only be applied after careful consideration of IPF severity and the patient’s performance status” the researchers wrote.

Their commentary, “Patients with IPF and lung cancer: diagnosis and management,” was published in the journal The Lancet Respiratory Medicine.

IPF is a life-threatening disease characterized by the thickening and stiffening of lung tissues due to collagen deposition (fibrosis). IPF patients are at a five times higher risk of lung cancer than the general population. In fact, up to 22 percent of IPF patients will develop this cancer, the group reports.

Several studies have looked at the mechanistic link between the two diseases, but it is still unclear how to best manage these patients, and most guidelines do not address this issue.

Diagnosing lung cancer is the first challenge IPF patients and clinicians face.

Recent guidelines suggest the use of positron emission tomography (PET) scans to detect metabolic active lesions bigger than 8 mm. However, if the scan is negative, chest CT scans or nonsurgical lung biopsy as surveillance measure is recommended.

In the case of positive PET scans, guidelines recommend surgical evaluation and removal. Despite the curative potential of this approach, it can pose added risks for IPF patients.

A previous retrospective study has shown that IPF patients who underwent surgery to treat non-small-cell lung cancer (NSCLC) had significantly higher mortality and poorer five-year survival rates than those without IPF.

Based on these data and the high risk for lung cancer among IPF patients, the researchers propose this diagnosis protocol:

• surveillance with high-resolution CT once a year in all patients with IPF;
• for IPF patients with small nodules (less than 8 mm), evaluation via high-resolution CT scans every 3 to 6 months;
• for IPF patients with larger nodules (greater than 8 mm) and confirmed tumor via PET-CT scan, collect tissue samples for diagnosis with CT-guided transthoracic needle biopsy (TTNB) or endobronchial ultrasound-guided transbronchial needle biopsy, which avoid many of the complications associated with surgery.

“If the patient is not suitable for biopsy, we suggest multidisciplinary discussion for a personalized approach,” the researchers added.

Information is also limited on the best chemotherapeutic regimen for patients with IPF and lung cancer. Studies have found higher toxicity effects in interstitial lung disease patients treated with conventional chemotherapeutic drugs.

Other treatment strategies such as immunomodulatory drugs have demonstrated potential to treat some patients, but they are linked to a higher risk of pulmonary inflammation.

Radiotherapy is also reported to not be a good option for patients with lung fibrosis, and should only be used in life-threatening situations, the researchers argue.

“We suggest that implementation of aggressive chemotherapeutic regimens should generally be avoided in patients with IPF and lung cancer because the risk for complications including acute exacerbations outweighs the benefits. The same applies to irradiation treatment, which is more detrimental than beneficial,” they wrote.

Use of proton beam therapy, which can deliver a more concentrated dose of radiation than conventional approaches, may be an alternative for this patient population.

To date, it is still unclear whether antifibrotic IPF therapies can be combined with anti-cancer therapies. Initially, nintedanib (an approved IPF therapy marketed as Ofev) was developed and approved to treat NSCLC, and preoperative treatment with pirfenidone (another IPF approved therapy marketed as Esbriet) was shown to reduce IPF exacerbations after cancer surgery. These data suggest that both these drugs can safely treat lung cancer patients with IPF.

The researchers suggest antifibrotic agents should continue to be used during diagnostic or therapeutic regimens for lung cancer. Final therapeutic decisions should be based on a multidisciplinary discussions on a case-by-case basis.

“A consensus statement on the diagnostic and therapeutic workup of such patients [with IPF and concomitant lung cancer] is sorely needed. In the meantime, management of patients with IPF and lung cancer should follow the premise to first do no harm,” the researchers concluded.

The group believes that improved strategies to prevent and promote early diagnosis of lung cancer are the cornerstone for timely and improved therapeutic interventions in this patient population.