High Incidence of EGFR Mutations in Pneumonic-Type Non-Small Cell Lung Cancer

Abstract

To retrospectively identify computed tomography (CT) features that correlate with epidermal growth factor receptor (EGFR) mutation in surgically resected pneumonic-type lung cancer (P-LC).A total of 953 consecutive patients with surgically resected lung cancer in the First Affiliated Hospital of Guangzhou Medical University from August 2011 to August 2013 were studied. The CT manifestations were reevaluated independently by 2 radiologists. The presence of pneumonic-type consolidation with pathological confirmed non-small lung cancer (NSCLC) was defined as P-LC. EGFR mutation was determined by direct DNA sequencing or amplification refractory mutation system-PCR. EGFR mutation rates as well as clinical and pathological manifestations between P-LC and control lung cancer patients were compared.P-LC was diagnosed in 85 patients. Among these patients, 82 were adenocarcinoma (including 78 cases of invasive adenocarcinoma and 4 cases of microinvasive adenocarcinoma), 2 were squamous carcinoma and 1 was other type. P-LC occurred more frequently in female (58.8% vs 37.1%, P < 0.01), nonsmoking (76.5% vs 56.5%, P = 0.001) and adenocarcinoma (58.8% vs 37.1%, P < 0.01) patients. Moreover, EGFR mutations were found in 39 of 52 P-LC patients (75%) and 263 of 542 non-P-LC NSCLC patients (48.5%). However, no difference was found on the mutation sites of EGFR. Histological type, sex, and radiological manifestations (P-LC vs non-P-LC) but not smoking or sequencing method can be served as the independent predictor of EGFR mutations.P-LC patients showed a significant higher incidence of EGFR mutations, which was independent of sex, histological type, and smoking history. The patients with imaging manifestation of pneumonic-type consolidation are highly suggested to perform EGFR mutation analysis to guide the sequential treatment.

A New Predictive Scoring System Based on Clinical Data and Computed Tomography Features for Diagnosing EGFR-mutated Lung Adenocarcinoma

“…Pneumonic-type lesions were previously known as consolidation-type lung cancer and were typically misdiagnosed as inflammatory pulmonary consolidation. A few studies demonstrated that patients with pneumonic-type lesions experience a significantly increased incidence of EGFR mutations, independent of sex, histologic type, and smoking history 16 . That research focused on patients before surgery, and our study focused on biopsy patients.…”

“…n Pneumonia-like consolidation = a homogenous or heterogeneous opacity lesion in the lung Unlike ggo, pneumonia-like consolidation effaces the blood vessel shadows, and occasionally an air bronchogram can be displayed without any bacterial or obstructive pneumonia 16 .…”

“…Some studies have attempted to determine the relationship between molecular findings and certain disease features such as sex, smoking status, the presence of ground-glass opacity (ggo) on imaging, and other features [16][17][18] . However, most of the reports described only the features with statistical significance, whose clinical value is limited.…”

Computed tomography and pathology evaluation of lung ground‑glass opacity

“…The BAC lesions were larger than AAH, with high density, air bronchogram, burring and leaf edges, thus these two types of cancer can be differentiated by CT. Yang et al reported that out of 55 cases of BAC, 56% showed air bronchogram (15). If BAC is of peripheral type, pleural indentation may be visible (16). Solid GGO is generally shown in adenocarcinoma, which is usually larger than an AHH lesion.…”

Proposals for revisions of the classification of lung cancers with multiple pulmonary sites: the radiologist’s, thoracic surgeon’s and oncologist’s point of view

“…In patients with this histopathological diagnosis , EGFR mutation analysis should be considered as mandatory. Indeed, EGFR mutations appear to be significantly high in this histological subtype (17).…”