EGFR and KRAS Mutations in the Non-Tumoral Lung. Prognosis in Patients with Adenocarcinoma

Clustering analysis and prognostic signature of lung adenocarcinoma based on the tumor microenvironment

Because of immunotherapy failure in lung adenocarcinoma, we have tried to find new potential biomarkers for differentiating different tumor subtypes and predicting prognosis. We identified two subtypes based on tumor microenvironment-related genes in this study. We used seven methods to analyze the immune cell infiltration between subgroups. Further analysis of tumor mutation load and immune checkpoint expression among different subgroups was performed. The least absolute shrinkage and selection operator Cox regression was applied for further selection. The selected genes were used to construct a prognostic 14-gene signature for LUAD. Next, a survival analysis and time-dependent receiver operating characteristics were performed to verify and evaluate the model. Gene set enrichment analyses and immune analysis in risk groups was also performed. According to the expression of genes related to the tumor microenvironment, lung adenocarcinoma can be divided into cold tumors and hot tumors. The signature we built was able to predict prognosis more accurately than previously known models. The signature-based tumor microenvironment provides further insight into the prediction of lung adenocarcinoma prognosis and may guide individualized treatment.

Bronchiolar adenomas (BA) - A detailed radio-pathologic analysis of six cases and review of literature

Bronchiolar adenomas (BAs)/ciliated muco-nodular papillary tumors (CMPTs), are small, peripheral lung nodules arising predominantly in the elderly that follow a benign course. They can be mistaken for adenocarcinomas on frozen section. Immunohistochemistry (IHC) for basal cell markers highlights the continuous layer of basal cells underlying the tumor cells in BAs. BAs are further subdivided into proximal-type and distal type. Six BAs were retrieved from the pathology archives. The cases were classified based on morphology into proximal and distal BAs. The clinical and radiological features were reviewed. Immunohistochemistry and special stains were performed. The most common radiological picture of BA/CMPT was of a solid nodule with SUV_max < 3 as seen in 60% cases. 40% cases showed cavitation on CT. On histological examination, four cases were morphologically classified as proximal BAs and two as distal BAs. In proximal BAs, TTF1 was focally positive only in the basal cells in three of four. The mucin stained acidic. In distal BAs, TTF1 was diffusely positive in both basal and luminal cells. There was scant intracellular neutral mucin. Both the distal BAs had concomitant neuroendocrine tumors in the same lobe. Though the number of cases evaluated in this study is too low to be statistically significant, this study provides additional evidence to the concept of BA classification based on site specific histology and supplementary immunohistochemistry and reiterates the radiological features that may help distinguish it from malignant lesions.

EGFR and KRAS Mutations in Lung Parenchyma of Subjects With EGFR/KRAS Wild-Type Lung Adenocarcinoma

The acquisition of driver mutations in non-tumoral cells appears to be very important during the carcinogenesis of adenocarcinoma (ADC). Recent studies suggest that cancer-related mutations may not necessarily be present only in malignant cells, but also in histologically “healthy cells”.

Objective: to demonstrate the presence of EGFR or KRAS mutations in non-tumoral lung cells in subjects with ADC and negative mutational status.

Results: mutations in EGFR or KRAS oncogenes were identified in the normal lung in 9.7% of the subjects. Exon 21 substitution L858R in EGFR was detected in two cases while the exon 19 deletion E746-A750 in the EGFR, the G12C and G12D substitutions in the KRAS were detected once. One patient presented three different mutations in the normal lung parenchyma (EGFR_L858R, KRAS_G12C and KRAS_G12D). The negative-mutation status of the tumor and the mutations detected in the “normal lung” were confirmed using highly sensitive and specific TaqMan PCR (CAST-PCR). No differences were found in terms of progression, progression-free survival or overall survival during the 18 months follow-up.

Conclusions: These results confirm the presence of driver mutations in the histologically normal lung parenchyma cells in the absence of mutations coexisting with the primary tumor.

Long-Term Recurrence of Completely Resected NSCLC

Introduction

The aim of this study is to evaluate the clinical backgrounds, including driver mutations, of those patients with early stage NSCLC who experienced recurrence beyond 5 years after complete resection.

Methods

We used a cohort of 512 consecutive cases of surgically resected NSCLC without other malignances from 2006 to 2011 in Aichi Cancer Center Hospital. The inclusion criteria for this cohort were patients with primary NSCLC who underwent a surgically curable operation.

Results

A total of 172 patients (32.8%) had recurrence after the surgery. Among the recurrent cases, 17 patients (3.3%) had a relapse more than 5 years after the surgery, and all except one (16 of 17, 94.1%) had driver mutations, including gene rearrangements.

Conclusions

Even in early stage NSCLC after complete resection, it was found that some cases had a relapse more than 5 years after the surgery. Most of these cases had some kind of driver mutations; so more than 5 years of postoperative surveillance may be beneficial, especially in those with driver gene mutants.

Clinicopathological and prognostic values of ErbB receptor family amplification in primary osteosarcoma

Osteosarcoma is a malignant bone tumor with extremely high invasion, metastasis and mortality. The prognosis of patients with osteosarcoma remains poor. The ErbB receptor family was found to be overexpressed in human cancers and associated with poor prognosis. However, the role of ErbB receptor family in osteosarcoma has not been fully understood. The present study aimed to investigate the clinicopathological and prognostic significances of ErbB receptors in primary osteosarcoma. Western blot (WB), reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and fluorescence in situ hybridization (FISH) were used to detect the protein and gene expression of ErbB receptors in 60 primary osteosarcoma specimens and 30 non-neoplastic bone tissues. WB and RT-qPCR analyses showed that the protein and mRNA expression levels of EGFR, ErbB3 and ErbB4 in osteosarcoma specimens were significantly higher than those in non-neoplastic bone tissues. Seventeen (28.33%), 15 (25.00%) and 15 (25.00%) osteosarcoma specimens presented with amplification of EGFR, ErbB3 and ErbB4 gene, respectively, which were significantly higher compared with non-neoplastic bone tissues. The amplification of ErbB3 and ErbB4 in osteosarcoma was associated with advanced surgical stage. The amplification of EGFR, ErbB3, ErbB4 and the co-amplification of EGFR-ErbB3, EGFR-ErbB4, ErbB3-ErbB4 was linked with poor response to chemotherapy and distant metastasis. The amplification of EGFR, ErbB3 and ErbB4, as well as their co-amplification demonstrated independent prognostic values for reduced survival time of osteosarcoma patients and may serve as potential therapeutic targets for osteosarcoma patients in the future.