ObjectiveTo investigate the correlation between histological subtypes of invasive lung adenocarcinoma and epithelial growth factor receptor (EGFR) gene mutation, and to provide a reference for clinical prediction of EGFR gene mutation status.MethodsFrom October 2017 to May 2019, 102 patients with invasive lung adenocarcinoma were collected, including 58 males and 44 females aged 62 (31-84) years. Invasive lung adenocarcinoma was classified into different histological subtypes. Scorpion probe amplification block mutation system (ARMS) real-time PCR was used to detect the mutation of EGFR gene in adenocarcinoma specimens, and the relationship between invasive lung adenocarcinoma subtypes and EGFR mutation status was analyzed.ResultsIn 102 patients with invasive lung adenocarcinoma, EGFR gene mutations were detected in 68 patients, and the mutation rate was 66.7% (68/102). The mutation sites were mainly concentrated in the exons 19 and 21; the mutation rate was higher in female patients (34/44, 77.3%) and non-smokers (34/58, 58.6%). EGFR mutation was mostly caused by acinar-like invasive lung adenocarcinoma, and was rare in solid-type lung adenocarcinoma. The EGFR gene mutation rates in different subtypes of adenocarcinoma were statistically different (P<0.05).ConclusionThe EGFR mutation status is related to gender, smoking status and histological subtype of invasive lung adenocarcinoma. EGFR mutation rates are higher in female, non-smoking and acinar-like invasive lung adenocarcinoma patients, and are lower in patients with solid type lung adenocarcinoma.
ObjectiveTo investigate the association between the baseline 18F-FDG PET/CT SUVmax and histological subtypes of ≤2 cm early peripheral lung adenocarcinoma (cN0).MethodsWe retrospectively reviewed the clinical data of consecutive patients who received baseline 18F-FDG PET/CT and underwent anatomic lung resection for ≤2 cm early peripheral lung adenocarcinoma from 2011 to 2014 in our institute.ResultsA total of 195 patients were enrolled in this study, including 86 males and 109 females, with an average age of 59.96±9.19 years. Twenty-two patients were pathologically confirmed with lymph node metastasis. One hundred and fifty-seven patients were in the subtype group 1, which included lepidic, acinar, and papillary predominant tumors. Thirty-eight patients were in the subtype group 2, which included solid and micropapillary predominant tumors. The 5-year survival rate was 79.0% and 58.0% in the subtype group 1 and subtype group 2, respectively (P=0.006). The median SUVmax was 2.00 (0.30-13.10) and 4.15 (1.20-17.90) in the subtype group 1 and subtype group 2, respectively (P=0.000). Logistic regression suggested that baseline SUVmax≥2.5 was an independent risk factor for the subtype group 2 (OR=6.635, 95%CI 2.510-17.545, P=0.000). The receiver operating characteristic curve suggested that the continuous SUVmax had an moderate predictive value for subtypes (area under the curve was 0.792, 95%CI 0.717-0.866).ConclusionBaseline 18F-FDG PET/CT SUVmax has certain predictive value for histological subtypes of ≤2 cm early peripheral lung adenocarcinoma.