Molecular characterization of small peripheral lung tumors based on the analysis of fine needle aspirates

CT-guided fine-needle aspiration biopsy of solitary pulmonary nodules under 15 mm in diameter: time for an afterthought?

Background

Many studies on fine-needle aspiration biopsy (FNAB) for undetermined pulmonary nodules reported that diagnostic accuracy tended to decline, whereas complication prevalence raised as the size of nodule decreased. Reconsideration on the effectiveness of FNAB would be appropriate considering the dramatic increase in the identification of small nodules with screening programs and new demands of target therapies. The aim of this study was to verify the efficacy of FNAB in pulmonary nodules smaller than 15 mm.

Methods

A retrospective, cohort study was conducted on patients with undetermined solitary pulmonary nodules (SPNs) who underwent computer tomography (CT) guided FNAB at our Institution from January 2012 to December 2014. Patients with SPNs with diameter up to 15 mm were considered; inclusion criteria comprised ASA 3, FEV1 <70% of predicted, cardiac comorbidity or previous chest surgery. FNAB diagnostic performance and clinical efficacy were calculated.

Results

Out of 225 patients referred for FNAB, 68 covered inclusion criteria. Forty-nine out of 68 smears (72%) were adequate for diagnosis. Specificity was 100% (95% CI: 77-100%), sensitivity was 100% (95% CI: 90-100%). Positive and negative predictive values were 1.0 (95% CI: 0.9-1.0) and 1.0 (95% CI: 0.77-1.0) respectively. A post-biopsy pneumothorax was detected in 27 cases (39%); the pneumothorax rate was significantly affected by the number of passages (P=0.01).

Conclusions

The satisfactory results of our study lead to reconsidering FNAB in patients with pulmonary nodules below 15 mm in diameter, especially in order to avoid unnecessary surgery.

A novel model for identification of prognostic indicator for clinical outcome of squamous cell lung carcinoma

Squamous cell carcinoma of the lung (SCCL) is the most common and aggressive lung tumor with poor clinical outcome. Identification and development of potential genes in prognostic process could be beneficial for clinical management. Sequencing data of 300 SCCL samples at level 3 were downloaded from The Cancer Genome Atlas (TCGA) data portal. Single-factor survival analysis was performed by the Kaplan-Meier method. Functional annotation was conducted on the high-frequency genes filtered out by 1000 times of the least absolute shrinkage and selectionator operator regression analysis. Meanwhile, multi-factor survival analysis was conducted and ROC curve were produced. Risk coefficient and expression level of each gene were used in the division of high-risk and low-risk genes. The number of high-risk genes of each sample was obtained, and the survival condition of different samples was analyzed. Finally, the number of optimal high-risk genes was obtained. Seven thousand nine hundred ninety-eight differential expressed mRNAs were obtained, and 2041 potential prognostic genes were screened out. Twenty one of the 22 high-frequency genes were showed to have significant impact on prognostic process. Single-factor analysis was performed on the 22 models, and eight efficient models were obtained, and seven among them were proven to be significant. By random testing, ≥5 genes and ≥6 genes were proven to be most stable and ≥6 genes were finally recognized as the beneficial indicator to distinguish lung squamous cell carcinoma. Twenty-two potential genes differentially expressed in lung squamous cell carcinoma were identified as potential prognostic indicator in clinical outcome, and the novel model in this study could be applied in other cancer types.

Feasibility of image-guided transthoracic core-needle biopsy in the BATTLE lung trial

BACKGROUND

As therapy for non-small-cell lung cancer (NSCLC) patients becomes more personalized, additional tissue in the form of core-needle biopsies (CNBs) for biomarker analysis is increasingly required for determining appropriate treatment and for enrollment into clinical trials. We report our experience with small-caliber percutaneous transthoracic (PT) CNBs for the evaluation of multiple molecular biomarkers in BATTLE (biomarker-integrated approaches of targeted therapy for lung cancer elimination), a personalized, targeted therapy NSCLC clinical trial.

METHODS

The medical records of patients who underwent PTCNB for consideration of enrollment in BATTLE were reviewed for diagnostic yield of 11 predetermined molecular markers and procedural complications. Univariate and multivariate analyses of factors related to patient and lesion characteristics were performed to determine possible influences on diagnostic yield.

RESULTS

One hundred and seventy PTCNBs were performed using 20-gauge biopsy needles in 151 NSCLC patients screened for the trial. The biopsy specimens of 82.9% of the patients were found to have adequate tumor tissue for analysis of the required biomarkers. On multivariate analysis, metastatic lesions were 5.4 times more likely to yield diagnostic tissue as compared with primary tumors (p = 0.0079). Pneumothorax and chest tube insertion rates were 15.3% and 9.4%, respectively.

CONCLUSIONS

Image-guided 20-gauge PTCNB is safe and provides adequate tissue for analysis of multiple biomarkers in the majority of patients being considered for enrollment into a personalized, targeted therapy NSCLC clinical trial. Metastatic lesions are more likely to yield diagnostic tissue as compared with primary tumors.

Diagnosis of lung cancer in small biopsies and cytology: implications of the 2011 International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification

The new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society lung adenocarcinoma classification provides, for the first time, standardized terminology for lung cancer diagnosis in small biopsies and cytology; this was not primarily addressed by previous World Health Organization classifications. Until recently there have been no therapeutic implications to further classification of NSCLC, so little attention has been given to the distinction of adenocarcinoma and squamous cell carcinoma in small tissue samples. This situation has changed dramatically in recent years with the discovery of several therapeutic options that are available only to patients with adenocarcinoma or NSCLC, not otherwise specified, rather than squamous cell carcinoma. This includes recommendation for use of special stains as an aid to diagnosis, particularly in the setting of poorly differentiated tumors that do not show clear differentiation by routine light microscopy. A limited diagnostic workup is recommended to preserve as much tissue for molecular testing as possible. Most tumors can be classified using a single adenocarcinoma marker (eg, thyroid transcription factor 1 or mucin) and a single squamous marker (eg, p40 or p63). Carcinomas lacking clear differentiation by morphology and special stains are classified as NSCLC, not otherwise specified. Not otherwise specified carcinomas that stain with adenocarcinoma markers are classified as NSCLC, favor adenocarcinoma, and tumors that stain only with squamous markers are classified as NSCLC, favor squamous cell carcinoma. The need for every institution to develop a multidisciplinary tissue management strategy to obtain these small specimens and process them, not only for diagnosis but also for molecular testing and evaluation of markers of resistance to therapy, is emphasized.

International association for the study of lung cancer/american thoracic society/european respiratory society international multidisciplinary classification of lung adenocarcinoma

INTRODUCTION

Adenocarcinoma is the most common histologic type of lung cancer. To address advances in oncology, molecular biology, pathology, radiology, and surgery of lung adenocarcinoma, an international multidisciplinary classification was sponsored by the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society. This new adenocarcinoma classification is needed to provide uniform terminology and diagnostic criteria, especially for bronchioloalveolar carcinoma (BAC), the overall approach to small nonresection cancer specimens, and for multidisciplinary strategic management of tissue for molecular and immunohistochemical studies.

METHODS

An international core panel of experts representing all three societies was formed with oncologists/pulmonologists, pathologists, radiologists, molecular biologists, and thoracic surgeons. A systematic review was performed under the guidance of the American Thoracic Society Documents Development and Implementation Committee. The search strategy identified 11,368 citations of which 312 articles met specified eligibility criteria and were retrieved for full text review. A series of meetings were held to discuss the development of the new classification, to develop the recommendations, and to write the current document. Recommendations for key questions were graded by strength and quality of the evidence according to the Grades of Recommendation, Assessment, Development, and Evaluation approach.

RESULTS

The classification addresses both resection specimens, and small biopsies and cytology. The terms BAC and mixed subtype adenocarcinoma are no longer used. For resection specimens, new concepts are introduced such as adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) for small solitary adenocarcinomas with either pure lepidic growth (AIS) or predominant lepidic growth with ≤ 5 mm invasion (MIA) to define patients who, if they undergo complete resection, will have 100% or near 100% disease-specific survival, respectively. AIS and MIA are usually nonmucinous but rarely may be mucinous. Invasive adenocarcinomas are classified by predominant pattern after using comprehensive histologic subtyping with lepidic (formerly most mixed subtype tumors with nonmucinous BAC), acinar, papillary, and solid patterns; micropapillary is added as a new histologic subtype. Variants include invasive mucinous adenocarcinoma (formerly mucinous BAC), colloid, fetal, and enteric adenocarcinoma. This classification provides guidance for small biopsies and cytology specimens, as approximately 70% of lung cancers are diagnosed in such samples. Non-small cell lung carcinomas (NSCLCs), in patients with advanced-stage disease, are to be classified into more specific types such as adenocarcinoma or squamous cell carcinoma, whenever possible for several reasons: (1) adenocarcinoma or NSCLC not otherwise specified should be tested for epidermal growth factor receptor (EGFR) mutations as the presence of these mutations is predictive of responsiveness to EGFR tyrosine kinase inhibitors, (2) adenocarcinoma histology is a strong predictor for improved outcome with pemetrexed therapy compared with squamous cell carcinoma, and (3) potential life-threatening hemorrhage may occur in patients with squamous cell carcinoma who receive bevacizumab. If the tumor cannot be classified based on light microscopy alone, special studies such as immunohistochemistry and/or mucin stains should be applied to classify the tumor further. Use of the term NSCLC not otherwise specified should be minimized.

CONCLUSIONS

This new classification strategy is based on a multidisciplinary approach to diagnosis of lung adenocarcinoma that incorporates clinical, molecular, radiologic, and surgical issues, but it is primarily based on histology. This classification is intended to support clinical practice, and research investigation and clinical trials. As EGFR mutation is a validated predictive marker for response and progression-free survival with EGFR tyrosine kinase inhibitors in advanced lung adenocarcinoma, we recommend that patients with advanced adenocarcinomas be tested for EGFR mutation. This has implications for strategic management of tissue, particularly for small biopsies and cytology samples, to maximize high-quality tissue available for molecular studies. Potential impact for tumor, node, and metastasis staging include adjustment of the size T factor according to only the invasive component (1) pathologically in invasive tumors with lepidic areas or (2) radiologically by measuring the solid component of part-solid nodules.

Genetically abnormal circulating cells in lung cancer patients: an antigen-independent fluorescence in situ hybridization-based case-control study

PURPOSE

We performed a study to determine if a fluorescence in situ hybridization (FISH)-based assay using isolated peripheral blood mononuclear cells (PBMCs) with DNA probes targeting specific sites on chromosomes known to have abnormalities in non-small cell lung cancer (NSCLC) cases could detect circulating genetically abnormal cells (CACs).

EXPERIMENTAL DESIGN

We evaluated 59 NSCLC cases with stage I through IV disease and 24 controls. PBMCs and matched tumors were hybridized with 2 two-color [3p22.1/CEP3 and 10q22.3 (SP-A)/CEP10) and 2 four-color [CEP3, CEP7, CEP17, and 9p21.3 (URO); and EGFR, c-MYC, 6p11-q11, and 5p15.2 (LAV)] FISH probes. Percentages of cytogenetically abnormal cells (CACs) in peripheral blood and in matched tumor specimens were quantified by using an automated fluorescent scanner. Numbers of CACs were calculated based on the percentage of CACs (defined as PBMCs with genetic abnormalities) per milliliter of blood and expressed per microliter of blood.

RESULTS

Patients with NSCLC had significantly higher numbers of CACs than controls. Mean number of CACs ranged from 7.23 +/- 1.32/microL for deletions of 10q22.3/CEP10 to 45.52 +/- 7.49/microL for deletions of 3p22.1/CEP3. Numbers of CACs with deletions of 3p22.1, 10q22.3, and 9p21.3, and gains of URO, increased significantly from early to advanced stage of disease.

CONCLUSIONS

We have developed a sensitive and quantitative antigen-independent FISH-based test for detecting CACs in peripheral blood of patients with NSCLC, which showed a significant correlation with the presence of cancer. If this pilot study can be validated in a larger study, CACs may have a role in the management of patients with NSCLC.

Imaging and cancer: a review

Multiple biomedical imaging techniques are used in all phases of cancer management. Imaging forms an essential part of cancer clinical protocols and is able to furnish morphological, structural, metabolic and functional information. Integration with other diagnostic tools such as in vitro tissue and fluids analysis assists in clinical decision-making. Hybrid imaging techniques are able to supply complementary information for improved staging and therapy planning. Image guided and targeted minimally invasive therapy has the promise to improve outcome and reduce collateral effects. Early detection of cancer through screening based on imaging is probably the major contributor to a reduction in mortality for certain cancers. Targeted imaging of receptors, gene therapy expression and cancer stem cells are research activities that will translate into clinical use in the next decade. Technological developments will increase imaging speed to match that of physiological processes. Targeted imaging and therapeutic agents will be developed in tandem through close collaboration between academia and biotechnology, information technology and pharmaceutical industries.