Impact of Cancer on Patients with Idiopathic Pulmonary Fibrosis

A retrospective review of the medical records of patients with idiopathic pulmonary fibrosis (IPF) published in Scientific Reports revealed that the rate of hospitalization for cancer-related complications was significantly higher in patients with IPF with lung cancer than in those with pulmonary cancer.

Moreover, those with IPF and lung cancer had a worse survival compared with those with extrapulmonary cancer. However, patients with IPF with early-stage lung cancer or extrapulmonary cancer, as well as those without cancer, were found to have comparable survival rates.

“Most studies have focused on the prognostic impact of lung cancer in patients with IPF,” the authors wrote. “However, there are limited data on extrapulmonary cancer in patients with IPF. Therefore, our study aimed to investigate the prognostic impact of extrapulmonary cancers in patients with IPF.”

In this retrospective review, researchers evaluated the medical records of patients diagnosed with IPF between 2001 and 2015. Of note, the death registry data were assembled using the Korean Ministry of the Interior and Safety, thus there were no missing data on the date of death.​

Patients were divided into 3 groups, including those with IPF without cancer (n = 440), IPF with lung cancer (n = 69), and IPF with extrapulmonary cancer (n = 70). In total 579 patients with IPF were assessed in the study, including 139 (24%) who had cancer; the most common types of cancer observed were lung (11.9%), gastric (2.4%), colorectal (1.9%), hepatocellular carcinoma (1.9%), and prostate cancer (1.0%).

Survival was found to be significantly worse in patients with lung cancer than in those without cancer (HR = 1.83, 95% CI, 1.35-2.48) or those with extrapulmonary cancer (HR = 1.70, 95% CI, 1.14-2.54). The results also demonstrated that the rates of emergency room (ER) visits, all-cause hospitalization, and intensive care unit (ICU) admission were significantly higher among patients with IPF with cancer than those without cancer; however, patients with lung cancer showed poorer survival than the other groups.

“These findings suggest that the higher incidence of cancer-related complications and the accompanying rate of respiratory hospitalization may account for survival differences among the groups,” the authors wrote.

Importantly though, due to the retrospective nature of the current study, inadequate or missing data may have impacted the outcome. Additionally, the data were obtained from a single hospital, and the sample size was relatively small for evaluating the exact prevalence of each type of cancer in patients with IPF. Further, cancer comorbidity among patients with IPF is less common; therefore, further population-based studies are needed to identify the exact prevalence of various cancers in patients with IPF and their prognostic impact.

“From these results, physicians should pay attention to the development and progression of cancer and its prognostic impact in patients with IPF,” the authors wrote. “Further population-based studies are needed to validate these results.”

Reference:

Lee HY, Cho J, Kwak N, et al. Prognostic impact of malignant diseases in idiopathic pulmonary fibrosis. Scientific Reports. doi: 10.1038/s41598-020-75376-2