Intrapatient Molecular and Histologic Heterogeneity After First-generation or Second-generation TKI Therapy of NSCLC Patients: Potential Clinical Impact on Subsequent third-generation TKI Treatment.

OBJECTIVES: The discovery of tyrosine kinase inhibitors (TKI) has remarkably improved the clinical course of patients with non-small cell lung cancer driven by Epidermal Growth Factor Receptor (EGFR) mutations. However, virtually in all cases, the disease resurfaces in a TKI-resistant form that is mainly linked to an acquired EGFR-T790M mutation, a MET amplification, or small cell lung cancer (SCLC) transformation. Third-generation TKIs are able to block tumor growth through an irreversible binding to the T790M-mutated receptor. Such new treatments require the diagnostic analysis of new pathologic tissue or a liquid biopsy to detect the presence of the T790M mutation. MATERIALS AND METHODS: Pre-TKI and post-TKI biopsies from 27 patients with an activating EGFR mutation were collected and analyzed for EGFR-T790M mutation, MET amplification, and SCLC transformation. RESULTS: The T790M mutation was found in 16 patients (59%) whereas MET gene amplification was found in 2 (10.5%) of 19 evaluated cases. The histologic transformation from adenocarcinoma (ADC) to SCLC was identified in 3 patients (11%). In one of them reversal from SCLC back to adenocarcinoma was observed. One patient had the T790M mutation concordantly detected in 2 synchronous lesions whereas another patient showed T790M positivity only in one of 2 specimens. In 4 patients longitudinal biopsies revealed T790M gains and losses not always according to biological expectations. CONCLUSIONS: Intrapatient molecular or histologic heterogeneity may be frequently found during routine treatment of non-small cell lung cancer patients. This biological aspect may have profound repercussions on subsequent therapeutic decisions, and therefore requires in-depth investigation.

Misleading impaired liver function in a non-small-cell lung cancer patient treated with pembrolizumab: a case report.

In the last few years, immunotherapy has become part of everyday clinical practice for the treatment of many solid tumors including metastatic non-small-cell lung cancer. These drugs, however, can yield a specific toxicity profile that consists of immune-related adverse events (irAEs). Hepatotoxicity is one of irAEs and occurs in about 1-3% of cases and may be manifested by the presence of increate levels of liver enzymes (aspartate aminotransferase, alanine aminotransferase) and/or biliary stasis evidence; in these cases, a differential diagnosis with other hepatic diseases must be considered. We present the case of a 73-year-old man who presented with an alteration in liver function during treatment with pembrolizumab (anti-programmed death 1 monoclonal antibody) for a stage IV nonsquamous non-small-cell lung cancer, which was initially mistaken for drug-induced irAEs hepatic toxicity.

Exogenous lipoid pneumonia induced by nasal decongestant.

INTRODUCTION: Lipoid pneumonia is a clinical condition that may be initially asymptomatic or confused with an infectious or malignant lung disease. OBJECTIVES: We report four cases of this pathological condition. METHODS: The first case concerned an 85-year old woman with bilateral confluent pulmonary opacities, ground-glass type. Diagnosis was based on the cytology of the bronchoalveolar lavage (BAL) fluid followed by its ultrastructural examination. The second case was a 47-year-old man with an isolated pulmonary nodule, which was surgically removed; the diagnosis of lipoid pneumonia was formulated on the basis of the histological and electron microscopy examination. The third case concerned a 73-year-old woman, with bilateral hypodense areas at the bases of the lungs where FDG PET/CT scan showed an increased uptake. Diagnosis was formulated by BAL cytology and electron microscopy examination. The fourth case was a 69-year-old man, who performed a virtual colonoscopy for diverticulosis putting in evidence a round mass (3 cm in diameter) with two small peripheral nodules, located in the pulmonary left lower lobe. The histopathological examination of transthoracic biopsy confirmed a lipoid pneumonia. RESULTS AND CONCLUSION: In all four cases, it was put in evidence a prolonged use of a nasal decongestant containing mineral oils. In literature, the most cases described are characterized by a subclinical evolution and were presented as ground glass opacities which evolve, in the later phases, in an interstitial involvement or in a peripheral mass, simulating a lung tumour.