Image-Guided Percutaneous Lung Needle Biopsy: How we do it.

Image-guided lung needle biopsy allows for minimally invasive diagnosis of lung pathology. In the setting of suspected malignancy, the biopsy not only confirms the diagnosis but also allows for molecular profiling, a requisite for tailored systemic therapy. Needle biopsy can also characterize non-neoplastic entities such as infections not responding to treatment and other inflammatory processes. A successful and safe lung needle biopsy starts with lesion and patient selection and careful pre-procedural evaluation. Here we review the indications and contraindications, diagnostic alternatives, approach planning and sequential procedural steps with the goal of maximizing both yield and patient safety. We discuss technical tips for preventing complications such as pleural anesthesia, the saline seal, the blood patch, the banana bend, hydro dissection, and the rapid needle out/patient rollover maneuver. We also review how to manage complications, avoid non-diagnostic biopsies, and provide recommendations for post-procedural observation and imaging follow-up.

Role of PTEN in basal cell derived lung carcinogenesis.

Lung adenocarcinoma (AdC) and lung squamous cell carcinoma (SCC) are the most common non-small cell lung cancer (NSCLC) subtypes, however, most genetic mouse models of lung cancer produce predominantly, if not exclusively, AdC. Whether this is secondary to targeting mutations to the distal airway cells or to the use of activating Kras mutations that drive AdC formation is unknown. We previously showed that targeting Kras(G12D) activation and transforming growth factor ß receptor type II (TGFßRII) deletion to airway basal cells via a keratin promoter induced formation of both lung AdC and SCC. In this study we assessed if targeting phosphatase and tensin homologue (PTEN) deletion to airway basal cells could initiate lung tumor formation or increase lung SCC formation. We found that PTEN deletion is capable of initiating both lung AdC and SCC formation when targeted to basal cells and although PTEN deletion is a weaker tumor initiator than Kras(G12D) with low tumor multiplicity and long latency, tumors initiated by PTEN deletion were larger and displayed more malignant conversion than Kras(G12D) initiated tumors. That PTEN deletion did not increase lung SCC formation compared to Kras(G12D) activation, suggests that the initiating genetic event does not dictate tumor histology when genetic alterations are targeted to a specific cell. These studies also confirm that basal cells of the conducting airway are capable of giving rise to multiple NSCLC tumor types.

Loss of transforming growth factor beta type II receptor increases aggressive tumor behavior and reduces survival in lung adenocarcinoma and squamous cell carcinoma.

PURPOSE: Lung adenocarcinoma and lung squamous cell carcinoma (SCC) are the most common non-small cell lung cancer (NSCLC) subtypes. This study was designed to determine whether reduced expression of TGFß type II receptor (TGFßRII) promotes lung adenocarcinoma and SCC carcinogenesis. EXPERIMENTAL DESIGN: We examined TGFßRII expression at the protein and mRNA levels in human NSCLC samples and assessed the relationship between TGFßRII expression and clinicopathologic parameters. To determine whether sporadic TGFßRII deletion in airway epithelial cells induces NSCLC formation, we targeted TGFßRII deletion alone and in combination with oncogenic Kras(G12D) to murine airways using a keratin 5 (K5) promoter and inducible Cre recombinase. RESULTS: Reduced TGFßRII expression in human NSCLC is associated with male gender, smoking, SCC histology, reduced differentiation, increased tumor stage, increased nodal metastasis, and reduced survival. Homozygous or heterozygous TGFßRII deletion in mouse airway epithelia increases the size and number of Kras(G12D)-initiated adenocarcinoma and SCC. TGFßRII deletion increases proliferation, local inflammation, and TGFß ligand elaboration; TGFßRII knockdown in airway epithelial cells increases migration and invasion. CONCLUSIONS: Reduced TGFßRII expression in human NSCLC is associated with more aggressive tumor behavior and inflammation that is, at least partially, mediated by increased TGFß1 expression. TGFßRII deletion in mouse airway epithelial cells promotes adenocarcinoma and SCC formation, indicating that TGFßRII loss plays a causal role in lung carcinogenesis. That TGFßRII shows haploid insufficiency suggests that a 50% TGFßRII protein reduction would negatively impact lung cancer prognosis.