Molecular testing guidelines for lung adenocarcinoma: Utility of cell blocks and concordance between fine-needle aspiration cytology and histology samples

Optimizing tissue stewardship in non-small cell lung cancer to support molecular characterization and treatment selection: statement from a working group of thoracic pathologists

Many patients with non-small cell lung cancer do not receive guideline-recommended, biomarker-directed therapy, despite the potential for improved clinical outcomes. Access to timely, accurate, and comprehensive molecular profiling, including targetable protein overexpression, is essential to allow fully informed treatment decisions to be taken. In turn, this requires optimal tissue management to protect and maximize the use of this precious finite resource. Here, a group of leading thoracic pathologists recommend factors to consider for optimal tissue management. Starting from when lung cancer is first suspected, keeping predictive biomarker testing in the front of the mind should drive the development of practices and procedures that conserve tissue appropriately to support molecular characterization and treatment selection.

The basics of commonly used molecular techniques for diagnosis, and application of molecular testing in cytology

Molecular diagnostics has expanded to become the standard of care for a variety of solid tumor types. With limited diagnostic material, it is often desirable to use cytological preparations to provide rapid and accurate molecular results. This review covers important pre-analytic considerations and limitations, and a description of common techniques that the modern cytopathologist should understand when ordering and interpreting molecular tests in practice.

Expert opinion on NSCLC small specimen biomarker testing - Part 1: Tissue collection and management

Biomarker testing is crucial for treatment selection in advanced non-small cell lung cancer (NSCLC). However, the quantity of available tissue often presents a key constraint for patients with advanced disease, where minimally invasive tissue biopsy typically returns small samples. In Part 1 of this two-part series, we summarise evidence-based recommendations relating to small sample processing for patients with NSCLC. Generally, tissue biopsy techniques that deliver the greatest quantity and quality of tissue with the least risk to the patient should be selected. Rapid on-site evaluation can help to ensure sufficient sample quality and quantity. Sample processing should be managed according to biomarker testing requirements, because tissue fixation methodology influences downstream nucleic acid, protein and morphological analyses. Accordingly, 10% neutral buffered formalin is recommended as an appropriate fixative, and the duration of fixation is recommended not to exceed 24-48 h. Tissue sparing techniques, including the 'one biopsy per block' approach and small sample cutting protocols, can help preserve tissue. Cytological material (formalin-fixed paraffin-embedded [FFPE] cytology blocks and non-FFPE samples such as smears and touch preparations) can be an excellent source of nucleic acid, providing either primary or supplementary patient material to complete morphological and molecular diagnoses. Considerations on biomarker testing, reporting and quality assessment are discussed in Part 2.

Concordance of Cytological Specimens with Histological Tissue for Detection of Epidermal Growth Factor Receptor Mutation in Non-Small Cell Lung Cancer: A Systematic Review

INTRODUCTION

There is increasing need for more testing in non-small cell lung cancer given the introduction of newer targeted therapies. Cytological specimens including conventional smears (CS), cell blocks (CB), and liquid-based cytology (LBC) are an alternative to histologic tissue (HT) specimens in detecting EGFR mutations, but the concordance of these 2 specimens is yet to be determined. The aim of the present systematic review is to determine the concordance rates between different cytologic specimens with HT in detecting EGFR mutations.

METHODS

PubMed, Cochrane Library, and Google Scholar were utilized in the primary search, along with reference lists of electronically retrieved full-text articles. Concordance rates were pooled together if 2 or more studies reporting the same type of cytologic specimen were available.

RESULTS

Overall, 15 studies were included in this review, with 13 studies included in the pooled analysis. There was an overall concordance rate of 92.8% in 593 paired cytologic and HT specimens, with LBC having the highest concordance rate of 96.0%, followed by CS and CB, each with a concordance rate of 95.8%, although the concordance rate of CS and/or CB was lower at 90.6% with a larger pool of studies. LBC was found to have a significantly higher concordance rate than CS and/or CB.

CONCLUSION

Cytological specimens have a high concordance rate in detecting EGFR mutations, when compared to HT. LBC has shown superior concordance rates compared to CS and CB. Cytological specimens should be considered as an additional and alternative source of diagnostic material for EGFR testing.

Challenges in Pathology Specimen Processing in the New Era of Precision Medicine

CONTEXT.—

Precision therapies for patients with driver mutations can offer deep and durable responses that correlate with diagnosis, metastasis prognosis, and improvement in survival. Such targeted therapies will continue to increase, pushing us to change our traditional approaches. We needed to search for new tools to effectively integrate technological advancements into our practices because of their capability to improve the efficiency and accuracy of our diagnostic and treatment approaches. Perhaps nothing is as relevant as identifying and implementing new workflows for processing pathologic specimens and for improving communication of critical laboratory information to and from clinicians for appropriate care of patients in an efficient and timely manner.

OBJECTIVES.—

To define the gold standard in delivering the best care for patients, to identify gaps in the process, and to identify potential solutions that would improve our process, including gaps related to knowledge, skills, attitudes, and practices.

DESIGN.—

We assembled a team across disciplines to systematically perform a gap analysis study to clarify the discrepancy between the current reality in pathology specimen processing and the desired optimal situation to deliver the results intended for patient care.

RESULTS.—

A practical collaborative workflow for specimen management seeking the cooperation of the stakeholders in each medical discipline to provide guidelines in specimen collection, delivery, processing, and reporting of results with the ultimate goal of improving patients' outcomes is provided.

CONCLUSIONS.—

New tools are required to effectively integrate data-driven approaches in specimen processing to meet the new demands.

Testing EGFR with Idylla on Cytological Specimens of Lung Cancer: A Review

The current standard of care for advanced non-small-cell lung cancer is based on detecting actionable mutations that can benefit from targeted therapy. Comprehensive genetic tests can have long turn-around times, and because EGFR mutations are the most prevalent actionable mutation, a quick detection would enable a prompt initiation of targeted therapy. Furthermore, the scarcity of diagnostic material means that sometimes only cytologic material is available. The Idylla™ EGFR assay is a real-time PCR–based method able to detect 51 EGFR mutations in 2.5 h. Idylla is validated for use only on FFPE sections, but some researchers described their experiences with cytological material. We reviewed the relevant literature, finding four articles describing 471 cases and many types of cytological input material: smears, cell-block sections, suspensions, and extracted DNA. The sensitivity, specificity, and limit of detection appear comparable to those obtained with histological input material, with one exception: the usage of scraped stained smears as input may reduce the accuracy of the test. In conclusion, usage of cytological material as input to the Idylla EGFR test is possible. A workflow where common mutations are tested first and fast, leaving rarer mutations for subsequent comprehensive profiling, seems the most effective approach.

Cell-blocks and other ancillary studies (including molecular genetic tests and proteomics)

Many types of elective ancillary tests may be required to support the cytopathologic interpretations. Most of these tests can be performed on cell-blocks of different cytology specimens. The cell-block sections can be used for almost any special stains including various histochemistry stains and for special stains for different microorganisms including fungi, Pneumocystis jirovecii (carinii), and various organisms including acid-fast organisms similar to the surgical biopsy specimens. Similarly, in addition to immunochemistry, different molecular tests can be performed on cell-blocks. Molecular tests broadly can be divided into two main types Molecular genetic tests and Proteomics.

Lung cancer cytology and small biopsy specimens: diagnosis, predictive biomarker testing, acquisition, triage, and management

In the 21st century, there has been a dramatic shift in the management of advanced-stage lung carcinoma, and this has coincided with an increasing use of minimally invasive tissue acquisition methods. Both have had significant downstream effects on cytology and small biopsy specimens. Current treatments require morphologic, immunohistochemical, and/or genotypical subtyping of non-small cell lung carcinoma. To meet these objectives, standardized classification of cytology and small specimen diagnoses, immunohistochemical algorithms, and predictive biomarker testing guidelines have been developed. This review provides an overview of current classification, biomarker testing, methods of small specimen acquisition and triage, clinical management strategies, and emerging technologies.

Role of Ancillary Techniques in Fluid Cytology

The cytologic evaluation of serous effusions may be challenging for a number of reasons. Distinction of benign, reactive conditions from malignancy represents the main focus when examining these specimens. The morphologic diagnosis of malignancy may be difficult due to the relative paucity of abnormal cells. In other situations, cellularity is not an issue, but the ability to confidently identify a second, foreign (i.e., tumor) population within a background mesothelial cells on the basis of cytomorphologic features alone may pose problems. Cases with definitive morphologic evidence of malignancy may require additional studies in order to determine the tumor subtype and, in the case of carcinoma, the primary site of origin. Cases in which a definitive and precise diagnosis of malignancy is made may be optimal candidates for further molecular testing in order to gain prognostic information and guide personal therapeutic decisions. Finally, while an inflammatory or infectious condition can be suggested on the basis of cellular components and associated background elements, the identification of causative agent(s) may be difficult without additional studies. In all of these situations, the use of ancillary studies and techniques is critical; their utility and appropriate application are the subject of this review.

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.

Rapid on-site evaluation using telecytology: A major cancer center experience

BACKGROUND

Rapid on-site evaluation (ROSE) with cytology preparations plays a critical role in minimally invasive procedures. The time spent by a pathologist performing ROSE is unpredictable and could be used for more cost-effective activities. The solution encountered by several institutions to address this issue is the use of telecytology (TC). This study analyzes the experience of using telecytology for ROSE in a major cancer center over a period of over 2 years.

METHODS

A retrospective analysis of all remote TC evaluations for adequacy on fine needle aspiration (FNA) and touch preparations (TP) of core biopsies (CB) performed at a major cancer center was performed. The preliminary adequacy assessment was then compared to the adequacy assessment at final diagnosis.

RESULTS

A total of 12 949 adequacy assessments were analyzed. The most common sites biopsied in our institution were lymph node, lung, and liver. There were 7725 adequacy assessments for CB (59.7%), while adequacy assessment for FNA specimens represented 40.3% (n = 5224) of the total number of specimens evaluated by ROSE. Perfect concordance between initial adequacy assessment and the adequacy assessment at final cytologic diagnosis was 93% (12 049/12 949). The final diagnosis adequacy upgrade rate was 6.7% (n = 863), and the adequacy downgrade (a specimen considered adequate on-site that was determined to be nondiagnostic on final examination) was 0.3% (n = 37).

CONCLUSIONS

TC can be easily implemented with the current technologies available. It is cost-effective and allows for better patient care with a more efficient use of the pathologist's time and laboratory resources.

Next-generation sequencing of non-small cell lung cancer using a customized, targeted sequencing panel: Emphasis on small biopsy and cytology

Background:

Next-generation sequencing (NGS) with a multi-gene panel is now available for patients with lung adenocarcinoma, but the performance characteristics and clinical utility of this testing are not well-described. We present the results of an extended 467 gene panel in a series of advanced, highly selected nonsmall cell lung cancer (NSCLC) patients using a range of specimens, including predominantly small biopsy and cytology specimens.

Materials and Methods:

A retrospective review of 22 NSCLC biopsies sent for NGS using an extended gene panel from January 2014 to July 2015. The customized NGS panel sequences 467 cancer-associated genes with exonic and intronic sequences obtained from purified tumor DNA. Genomic alterations, patient characteristics, and success of testing were determined.

Results:

The majority of samples tested were metastatic lung adenocarcinoma on final pathology. Of the 22 specimens tested, 5 (22.7%) were surgical resections and 17 (77.3%) were small biopsy and cytology specimens. Twenty-one (95%) of the specimens were adequate for full sequencing and yielded a total of 204 genomic alterations (average 8.9 per tumor), of which 17 (average 0.81 per tumor) were actionable and/or clinically relevant. Genomic alterations were found most commonly in the TP53, EGFR, EPHB1, MLL3, APC, SETD2, KRAS, DNMT3A, RB1, CDKN2A, ARID1A, EP300, KDM6B, RAD50, STK11, and BRCA2 genes.

Conclusions:

NGS using a comprehensive gene panel was performed successfully in 95% of all NSCLC cases in this series, including 94% small biopsy and cytology specimens and 100% surgical resections. This custom assay was performed on a range of tumor specimens and demonstrates that small specimens are able to provide a similar depth of information as larger ones. As many patients present at an advanced stage and only small specimens are obtained, the information these provide has the potential for guiding treatment in highly selected patients with advanced lung adenocarcinoma.

Yield and Clinical Utility of Next-Generation Sequencing in Selected Patients With Lung Adenocarcinoma

BACKGROUND

Next-generation sequencing is available for assessing genomic alterations in non-small-cell lung cancer (NSCLC), although the performance characteristics and clinical utility has not been well characterized. This technique can be used to sequence hundreds of known cancer-associated genes. Our aim was to investigate the diagnostic success and clinically relevant results of extensive sequencing in NSCLC patients.

PATIENTS AND METHODS

A case series of 49 NSCLC patients was used to determine the success of extended next-generation sequencing, record genomic alterations, and evaluate clinical utility. Data were collected in a retrospective review. Sequencing was performed using a hybridization capture of 3320 exons from 236 cancer-related genes and 47 introns of 19 genes applied to ≥50 ng of DNA and sequenced to high, uniform coverage of 622 times.

RESULTS

Sequencing was successful in 29 of 32 (91%) surgical/excisional specimens, and 12 of 17 (71%) nonsurgical specimens including an endoscopic forceps biopsy, core needle biopsies, fine-needle aspirates, and effusion cytologies. All 5 transthoracic core needle biopsies failed. A total of 179 genomic alterations (average 4.37 per tumor) were found. A total of 63 were clinically relevant (average 1.54 per tumor). The most frequently mutated genes were tumor protein p53, cyclin-dependent kinase inhibitor 2A, megalencephalic leukoencephalopathy with subcortical cysts 1, rapamycin-insensitive companion of mammalian target of rapamycin, epithelial growth factor receptor, SWI/SNF Related, Matrix Associated, Actin Dependent Regulator Of Chromatin, Subfamily A, Member 4, cyclin-dependent kinase inhibitor 2B, phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit α, Kirsten rat sarcoma viral oncogene homolog, Erb-B2 receptor tyrosine kinase 2, Serine/Threonine Kinase 11, and NK2 Homeobox 1. Sequencing results led to a change in management in 7 of 49 cases (14.3%).

CONCLUSION

Extended next-generation sequencing was performed successfully in 41 (83.7%) cases of NSCLC using a range of pathology specimens. Testing had the potential to affect treatment decisions in selected patients.

Comprehensive Genomic Profiling Facilitates Implementation of the National Comprehensive Cancer Network Guidelines for Lung Cancer Biomarker Testing and Identifies Patients Who May Benefit From Enrollment in Mechanism-Driven Clinical Trials

BACKGROUND

The National Comprehensive Cancer Network (NCCN) guidelines for patients with metastatic non-small cell lung cancer (NSCLC) recommend testing for EGFR, BRAF, ERBB2, and MET mutations; ALK, ROS1, and RET rearrangements; and MET amplification. We investigated the feasibility and utility of comprehensive genomic profiling (CGP), a hybrid capture-based next-generation sequencing (NGS) test, in clinical practice.

METHODS

CGP was performed to a mean coverage depth of 576× on 6,832 consecutive cases of NSCLC (2012-2015). Genomic alterations (GAs) (point mutations, small indels, copy number changes, and rearrangements) involving EGFR, ALK, BRAF, ERBB2, MET, ROS1, RET, and KRAS were recorded. We also evaluated lung adenocarcinoma (AD) cases without GAs, involving these eight genes.

RESULTS

The median age of the patients was 64 years (range: 13-88 years) and 53% were female. Among the patients studied, 4,876 (71%) harbored at least one GA involving EGFR (20%), ALK (4.1%), BRAF (5.7%), ERBB2 (6.0%), MET (5.6%), ROS1 (1.5%), RET (2.4%), or KRAS (32%). In the remaining cohort of lung AD without these known drivers, 273 cancer-related genes were altered in at least 0.1% of cases, including STK11 (21%), NF1 (13%), MYC (9.8%), RICTOR (6.4%), PIK3CA (5.4%), CDK4 (4.3%), CCND1 (4.0%), BRCA2 (2.5%), NRAS (2.3%), BRCA1 (1.7%), MAP2K1 (1.2%), HRAS (0.7%), NTRK1 (0.7%), and NTRK3 (0.2%).

CONCLUSION

CGP is practical and facilitates implementation of the NCCN guidelines for NSCLC by enabling simultaneous detection of GAs involving all seven driver oncogenes and KRAS. Furthermore, without additional tissue use or cost, CGP identifies patients with "pan-negative" lung AD who may benefit from enrollment in mechanism-driven clinical trials.

IMPLICATIONS FOR PRACTICE

National Comprehensive Cancer Network guidelines for patients with metastatic non-small cell lung cancer (NSCLC) recommend testing for several genomic alterations (GAs). The feasibility and utility of comprehensive genomic profiling were studied in NSCLC and in lung adenocarcinoma (AD) without GAs. Of patients with NSCLC, 71% harbored at least one GA to a gene listed in the guidelines or KRAS; 273 cancer-related genes were altered in at least 0.1% of the AD cases. Although logistical and administrative hurdles limit the widespread use of next-generation sequencing, the data confirm the feasibility and potential utility of comprehensive genomic profiling in clinical practice.

Respiratory Cytology--Current Trends Including Endobronchial Ultrasound-Guided Biopsy and Electromagnetic Navigational Bronchoscopy: Analysis of Data From a 2013 Supplemental Survey of Participants in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology

CONTEXT

Nongynecologic cytology (NGC) practices are expanding in relationship to historical gynecologic cytology screening programs. Bronchopulmonary cytology is experiencing an evolution regarding new procedural types. The College of American Pathologists (CAP) tracks practice patterns in NGC by developing questionnaires, surveying participants, and analyzing respondent data.

OBJECTIVE

To analyze responses to a 2013 CAP supplemental survey from the Interlaboratoy Comparison Program on bronchopulmonary NGC.

DESIGN

The "NGC 2013 Supplemental Questionnaire: Demographics in Performance and Reporting of Respiratory Cytology" was mailed to 2074 laboratories.

RESULTS

The survey response rate was 42% (880 of 2074) with 90% of respondents (788 of 880) indicating that their laboratories evaluated cytology bronchopulmonary specimens. More than 95% of respondents indicated interpreting bronchial washings (765 of 787) and bronchial brushings (757 of 787). A minority of laboratories (43%, 340 of 787) dealt with endobronchial ultrasound-guided samples, and an even smaller fraction of laboratories (14%, 110 of 787) saw cases from electromagnetic navigational bronchoscopy. Intraprocedural adequacy assessments by pathologists (and less often by cytotechnologists or pathologists-in-training) were routinely performed in percutaneous transthoracic aspiration cases (74%, 413 of 560) with less involvement for other case types. Most laboratories reported that newly diagnosed primary pulmonary adenocarcinomas were triaged for molecular testing of epidermal growth factor receptor and anaplastic lymphoma kinase.

CONCLUSIONS

The parameters examined in this 2013 survey provide a snapshot of current pulmonary cytopathology practice and may be used as benchmarks in the future.

Analysis of Mutations in Epidermal Growth Factor Receptor Gene in Korean Patients with Non-small Cell Lung Cancer: Summary of a Nationwide Survey

Background:

Analysis of mutations in the epidermal growth factor receptor gene (EGFR) is important for predicting response to EGFR tyrosine kinase inhibitors. The overall rate of EGFR mutations in Korean patients is variable. To obtain comprehensive data on the status of EGFR mutations in Korean patients with lung cancer, the Cardiopulmonary Pathology Study Group of the Korean Society of Pathologists initiated a nationwide survey.

Methods:

We obtained 1,753 reports on EGFR mutations in patients with lung cancer from 15 hospitals between January and December 2009. We compared EGFR mutations with patient age, sex, history of smoking, histologic diagnosis, specimen type, procurement site, tumor cell dissection, and laboratory status.

Results:

The overall EGFR mutation rate was 34.3% in patients with non-small cell lung cancer (NSCLC) and 43.3% in patients with adenocarcinoma. EGFR mutation rate was significantly higher in women, never smokers, patients with adenocarcinoma, and patients who had undergone excisional biopsy. EGFR mutation rates did not differ with respect to patient age or procurement site among patients with NSCLC.

Conclusions

EGFR mutation rates and statuses were similar to those in published data from other East Asian countries.

Limited Resection Versus Lobectomy for Older Patients With Early-Stage Lung Cancer: Impact of Histology

PURPOSE

Limited resection has been increasingly used in older patients with stage IA lung cancer. However, the equivalency of limited resection versus lobectomy according to histology is unknown.

METHODS

We identified patients older than 65 years with stage IA invasive adenocarcinoma or squamous cell carcinoma ≤ 2 cm who were treated with limited resection (wedge or segmentectomy) or lobectomy in the Surveillance, Epidemiology, and End Results-Medicare database. We estimated propensity scores that predicted the use of limited resection and compared survival of patients treated with limited resection versus lobectomy. Treatments were considered equivalent if the upper 95th percentile of the hazard ratio (HR) for limited resection was ≤ 1.25.

RESULTS

Overall, 27% of 2,008 patients with adenocarcinoma and 32% of 1,139 patients with squamous cell carcinoma underwent limited resection. Survival analyses, adjusted for propensity score by using inverse probability weighting, showed that limited resection was not equivalent to lobectomy in patients with adenocarcinoma (HR, 1.21; upper 95% CI,1.34) or squamous cell carcinoma (HR, 1.21; upper 95% CI, 1.39). Although patients with adenocarcinomas treated with segmentectomy had equivalent survival rates to those treated with lobectomy (HR, 0.97; upper 95% CI, 1.07), outcomes of those treated with wedge resection (HR, 1.29; upper 95% CI, 1.42) did not. Among patients with squamous cell carcinoma, neither wedge resection (HR, 1.34; upper 95% CI, 1.53) nor segmentectomy (HR, 1.19; upper 95% CI, 1.36) were equivalent to lobectomy.

CONCLUSION

We found generally that limited resection is not equivalent to lobectomy in older patients with invasive non-small-cell lung cancer ≤ 2 cm in size, although segmentectomy may be equivalent in patients with adenocarcinoma.

Poor cell block adequacy rate for molecular testing improved with the addition of Diff-Quik-stained smears: Need for better cell block processing

BACKGROUND

In the era of personalized medicine, requests for molecular testing of specimens obtained with minimally invasive procedures such as fine-needle aspiration have been increasing. Although cell blocks (CBs) are the recommended specimens for molecular testing, their performance has not been well analyzed. The objective of this study was to assess the frequency and types of samples deemed unsatisfactory for molecular testing (quantity not sufficient [QNS]).

METHODS

One year after the implementation of careful monitoring of QNS cases, cases submitted for lung cancer molecular testing were analyzed for the QNS rate. When the cases were rejected for the inadequacy of CBs of cytology specimens, air-dried, Diff-Quik (DQ)-stained smears were reviewed and used if they were adequate. The QNS rates were compared across 4 specimen categories: large resection, small biopsy, CB alone, and CB with DQ smears.

RESULTS

One hundred seventy-six cases were studied, and 45 (25.6%) were unsatisfactory. Only 1 of 73 large resection specimens was rejected because of decalcification. The QNS rate for small biopsy specimens was 35.9% (28 of 78), whereas 64% (16 of 25) of cytology cases ordered on CBs were rejected. In combination with DQ smears, the QNS rate of cytology specimens was 32% (8 of 25), which was a significant improvement over CBs only (P = .024) and was not significantly different from the QNS rate for small biopsies (P = .671).

CONCLUSIONS

The utilization of DQ-stained smears for molecular testing improves the adequacy of cytologic samples and provides a minimally invasive alternative to surgical biopsy when molecular analysis of tumor material is necessary.

FNA, core biopsy, or both for the diagnosis of lung carcinoma: Obtaining sufficient tissue for a specific diagnosis and molecular testing

BACKGROUND

Increasingly, minimally invasive procedures are performed to assess lung lesions and stage lung carcinomas. In cases of advanced-stage lung cancer, the biopsy may provide the only diagnostic tissue. The aim of this study was to determine which method-fine-needle aspiration (FNA), core biopsy (CBx), or both (B)--is optimal for providing sufficient tissue for rendering a specific diagnosis and pursuing molecular studies for guiding tumor-specific treatment.

METHODS

A search was performed for computed tomography-guided lung FNA, CBx, or B cases with rapid onsite evaluation. Carcinomas were assessed for the adequacy to render a specific diagnosis; this was defined as enough refinement to subtype a primary carcinoma or to assess a metastatic origin morphologically and/or immunohistochemically. In cases of primary lung adenocarcinoma, the capability of each modality to yield sufficient tissue for molecular studies (epidermal growth factor receptor, KRAS, or anaplastic lymphoma kinase) was also assessed.

RESULTS

There were 210 cases, and 134 represented neoplasms, including 115 carcinomas. For carcinomas, a specific diagnosis was reached in 89% of FNA cases (33 of 37), 98% of CBx cases (43 of 44), and 100% of B cases (34 of 34). For primary lung adenocarcinomas, adequate tissue remained to perform molecular studies in 94% of FNA cases (16 of 17), 100% of CBx cases (19 of 19), and 86% of B cases (19 of 22). No statistical difference was found among the modalities for either reaching a specific diagnosis (p = .07, Fisher exact test) or providing sufficient tissue for molecular studies (p = .30, Fisher exact test).

CONCLUSIONS

The results suggest that FNA, CBx, and B are comparable for arriving at a specific diagnosis and having sufficient tissue for molecular studies: they specifically attained the diagnostic and prognostic goals of minimally invasive procedures for lung carcinoma.

Assessment of EGFR and KRAS mutation status from FNAs and core-needle biopsies of non-small cell lung cancer

BACKGROUND

Molecular testing to determine gene mutation status is now the recommended standard of care for patients with advanced or metastatic Non-small cell lung cancer (NSCLC). Because the majority of patients with NSCLC present with metastatic disease, minimally invasive procedures are necessary for diagnosis, staging, and molecular analysis. However, the resulting samples have perceived limitations in the oncology community, and most commercially available tests have not been validated for these sample types. The current study was undertaken to assess the feasibility of determining epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation status in fine-needle aspirates (FNAs) and core-needle biopsies (CNBs) after staining with Papanicolaou or hematoxylin and eosin, respectively.

METHODS

Gene mutation status was determined in 140 NSCLC tumor samples with proprietary tests for EGFR and KRAS mutations (cobas tests) followed by Sanger sequencing of exons 18 through 21 of the EGFR gene and exon 2 of the KRAS gene. The results were analyzed based on FNA (n = 91) or CNB (n = 49) sampling.

RESULTS

The cobas tests yielded valid results in the majority of FNA and CNB samples for both EGFR (97.9%) and KRAS (93.6%). Moreover, valid results were obtained for 90% of samples that had DNA concentrations below the values recommended by the manufacturer. For samples with valid results from both cobas testing and Sanger sequencing, 95.7% and 93% agreement were observed for EGFR status and KRAS status, respectively.

CONCLUSIONS

Gene mutation testing can be successfully performed on cytology and CNB samples, expanding the potential of personalized cancer treatment to patients who have limited tissue samples.