Gefitinib-induced pneumonitis in non-small cell lung cancer: radiological and clinical findings in five patients

Pulmonary complications of tyrosine kinase inhibitors and immune checkpoint inhibitors in patients with non-small cell lung cancer

The understanding of cancer biology and the identification of various molecular pathways and targeted oncogenic drivers have led to a paradigm shift in treatment of non-small cell lung cancer. In the last two decades, the therapeutic approach for non-small cell lung cancer (NSCLC) has gradually transitioned from empiric treatment with chemotherapeutic regimens to personalized medicine with precision targets. The major key players in these novel approaches involve targeted therapy, such as tyrosine kinase inhibitors (TKI) and immunotherapy, such as immune checkpoint inhibitors (ICI) blocking intrinsic down regulators of immunity, to achieve anti-cancer effects. These novel agents are generally better tolerated than chemotherapeutics and it is essential to be cognizant of the various drug related adverse effects. Regular follow up of patients with NSCLC by chest computed tomography (CT) surveillance to monitor for disease progression or recurrence is a prerequisite. It is becoming increasingly challenging to identify pulmonary complications related to the use of novel TKI and ICI. Our review focuses on various pulmonary complications of TKI and ICI in patients undergoing treatment for NSCLC, chest CT manifestations, management strategies, and treatment outcomes described in various case reports and case series.

Pulmonary Toxicities of Gefitinib in Patients With Advanced Non-Small-Cell Lung Cancer: A Meta-Analysis of Randomized Controlled Trials

Gefitinib is a selective tyrosine kinase inhibitor of the epidermal growth factor receptor (EGFR) used to treat adults with EGFR mutation-positive non-small-cell lung cancer (NSCLC). Clinical benefits of gefitinib administration in NSCLC patients have been observed in clinical practice, but the extent of the pulmonary toxicity of gefitinib in patients with advanced NSCLC remains unclear. The aim of this systematic review was to evaluate the overall incidence and risk of gefitinib-related pulmonary toxicity in advanced NSCLC patients. Relevant trials were identified from the databases of Pubmed, Embase, Cochrane Library, and the clinicaltrials.gov of the U.S. National Institutes of Health. The outcomes included the overall incidence, odds ratios (ORs), and 95% confidence intervals (CIs). Fixed-effects models were used in the statistical analyses according to the heterogeneity of the included studies. According to the data from the included trials, the overall incidence of high-grade hemoptysis, pneumonia, pneumonitis, and interstitial lung disease (ILD) was 0.49% (95% CI: 0.24%-0.99%), 2.33% (95% CI: 1.47%-3.66%), 2.24% (95% CI: 1.34%-3.72%), and 1.43% (95% CI: 0.98%-2.09%), respectively. The pooled ORs of high-grade hemoptysis, pneumonia, pneumonitis, and ILD were 1.73 (95% CI: 0.46-6.52; P = 0.42), 0.99 (95% CI: 0.66-1.49; P = 0.95), 4.70 (95% CI: 1.48-14.95; P = 0.0087), and 2.64 (95% CI: 1.22-5.69; P = 0.01), respectively. Gefitinib was associated with a significantly increased risk of high-grade/fatal ILD and pneumonitis compared with the controls, whereas the risk of other high-grade pulmonary events (pneumonia and hemoptysis) was not significant. Careful surveillance of gefitinib-related pulmonary toxicity is critical for the safe use of this drug.

Mechanisms of Gefitinib-mediated reversal of tamoxifen resistance in MCF-7 breast cancer cells by inducing ERα re-expression

Estrogen receptor (ER)-positive breast cancer patients may turn ER-negative and develop acquired drug resistance, which compromises the efficacy of endocrine therapy. By investigating the phenomenon that gefitinib can re-sensitise tamoxifen (TAM)-resistant MCF-7 breast cancer cells (MCF-7/TAM) to TAM, the present study verified that gefitinib could reverse the acquired drug resistance in endocrine therapy and further explored the underlying mechanism.ERα-negative MCF-7/TAM cells were established. Upon treating the cells with gefitinib, the mRNA and protein levels of ERα and ERβ, as well as the expression of molecules involved in the MAPK pathway, were examined using the RT-PCR and immunocytochemistry. The RT-PCR results showed that the mRNA levels of ERα and ERβ in MCF-7/TAM cells were up-regulated following gefitinib treatment; specifically, ERα was re-expressed, and ERβ expression was up-regulated. The expression of molecules involved in the MAPK pathway, including RAS, MEK1/2, and p-ERK1/2, in MCF-7/TAM cells was significantly up-regulated, compared with MCF-7 cells. After the gefitinib treatment, the expression levels of MEK1/2 and p-ERK1/2 were significantly down-regulated. ERα loss is the primary cause for TAM resistance. Gefitinib reverses TAM resistance primarily by up-regulating the ERα mRNA level and inducing the re-expression of ERα. The MAPK pathway plays a key role in ERα re-expression.

Successful treatment of gefitinib-induced acute interstitial pneumonitis with high-dose corticosteroid: a case report and literature review

Cytotoxic chemotherapy offers a modest benefit for patients with advanced non-small cell lung cancer (NSCLC), with response rates of 20-35% and median survival of 10-12 months. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), gefitinib and erlotinib are active against lung cancer. In retrospective studies, EGFR-TKI therapy among patients harboring EGFR mutations showed response rates higher than 65% and a median survival of 20-30 months. Gefitinib is well tolerated and less toxic compared to conventional cytotoxic drugs, but gefitinib-related interstitial lung disease (ILD) has been reported as a serious adverse effect. Although the mechanism remains unknown, multivariate analysis revealed male sex, history of smoking, and the coexistence of interstitial pneumonia or pre-existence of pulmonary fibrosis and poor performance status were all significant risk factors. Here, we reported a case of gefitinib pneumonitis with severe hypoxemia and impending respiratory failure who showed poor response to intermediate dose of systemic steroids but good recovery with high-dose pulse therapy.