EGFR mutations detected on cytology samples by a centralized laboratory reliably predict response to gefitinib in non-small cell lung carcinoma patients

Radiomic-signature changes after early treatment improve the prediction of progression-free survival in patients with advanced anaplastic lymphoma kinase-positive non-small cell lung cancer

BACKGROUND

The prognosis of lung cancer varies widely, even in cases wherein the tumor stage, genetic mutation, and treatment regimens are the same. Thus, an effective means for risk stratification of patients with lung cancer is needed.

PURPOSE

To develop and validate a combined model for predicting progression-free survival and risk stratification in patients with advanced anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) treated with ensartinib.

MATERIAL AND METHODS

We analyzed 203 tumor lesions in 114 patients and evaluated average radiomic feature measures from all lesions at baseline and changes in these features after early treatment (Δradiomic features). Combined models were developed by integrating clinical with radiomic features. The prediction performance and clinical value of the proposed models were evaluated using receiver operating characteristic analysis, calibration curve, decision curve analysis (DCA), and Kaplan-Meier survival analysis.

RESULTS

Both the baseline and delta combined models achieved predictive efficacy with a high area under the curve. The calibration curve and DCA indicated the high accuracy and clinical usefulness of the combined models for tumor progression prediction. In the Kaplan-Meier analysis, the delta and baseline combined models, Δradiomic signature, and two selected clinical features could distinguish patients with a higher progression risk within 42 weeks. The delta combined model had the best performance.

CONCLUSION

The combination of clinical and radiomic features provided a prognostic value for survival and progression in patients with NSCLC receiving ensartinib. Radiomic-signature changes after early treatment could be more valuable than those at baseline alone.

Clinical utility of liquid biopsy and integrative genomic profiling in early-stage and oligometastatic cancer patients treated with radiotherapy

BACKGROUND

Liquid biopsy and Integrative Genomic Profiling (IGP) are yet to be implemented into routine Radiation Oncology. Here we assess the utility of germline, tumour and circulating cell-free DNA-based genomic analyses for the clinical management of early-stage and oligometastatic cancer patients treated by precision radiotherapy.

METHODS

We performed germline, tissue- and liquid biopsy NGS panels on 50 early-stage/oligometastatic cancer patients undergoing radiotherapy. We also monitored ctDNA variants in serial liquid biopsies collected during radiotherapy and follow-up and evaluated the clinical utility of such comprehensive approach.

RESULTS

The integration of different genomic studies revealed that only 1/3 of the liquid biopsy variants are of tumour origin. Altogether, 55 tumour variants (affecting 3/4 of the patients) were considered potentially actionable (for treatment and prognosis), whereas potential follow-up biomarkers were identified in all cases. Germline cancer-predisposing variants were present in three patients, which would have not been eligible for hereditary cancer testing according to clinical guidelines. The presence of detectable ctDNA variants before radiotherapy was associated with progression-free survival both in oligometastatic patients and in those with early-stage.

CONCLUSIONS

IGP provides both valuable and actionable information for personalised decision-making in Radiation Oncology.

EGFR testing in paraffin-embedded cell block cytology material is reliable with increased detection for effusion fluid

INTRODUCTION

Cytology is integral to lung cancer diagnosis. Aspiration and exfoliative fluid specimens represent valuable tumor material for molecular testing. In this study, a large retrospective cohort of EGFR tests was reviewed to address the adequacy, detection and discrepancy rate in tests performed with cytology material.

METHODS

EGFR tests performed from 2013 to 2022 were reviewed and classified by the modality of obtaining tissue and by tissue type. EGFR tests for tissue specimens were performed on unstained sections of paraffin-embedded material on glass slides. Adequacy and types of mutation(s) detected were analysed. Cases where multiple EGFR testing was performed on the same patient were reviewed for discordance.

RESULTS

There were 5,504 tests retrieved, with 1,855, 3,607 and 42 performed on cytology, surgical and blood specimens. Lung and excision specimens were more often adequate (p < 0.001). Cytology material showed lower adequacy rates (p < 0.01). EGFR detection (positive) rate was higher in pleural fluid compared to biopsy (59.8 % vs 50.7 %, p = 0.022), but similar between lung and lymph node cytology and non-cytology specimens. Effusion fluid specimens had the highest adequacy (81.5 %) and detection rate (59.3 %) among cytology specimens (p < 0.001). Four (4.4 %) cases showed discordant results in cytology specimens. Two were false negatives in the non-cytology material. Only in one case was cytology material genuinely discrepant. The remaining discordance was attributed to the interval treatment effect.

CONCLUSION

The findings support that EGFR testing in cell block is reliable and complements tissue material. In addition, pleural fluid appears to be superior to pleural biopsies for molecular testing.

Accuracy of next-generation sequencing for molecular profiling of small specimen of lung cancer: a prospective pilot study of side-by-side comparison

Background

Successful practice of precision medicine in advanced lung cancers relies on therapeutic regimens tailored to individual molecular characteristics. The aim of this study was to investigate the accuracy of small specimens for molecular profiling using next-generation sequencing (NGS).

Methods

Genetic alternations, tumor mutational burden (TMB), status of microsatellite instability (MSI), and expression of programmed death ligand 1 (PD-L1) were compared side-by-side between the concurrently obtained core needle biopsy (CNB) and resection specimens in 17 patients with resectable non-small cell lung cancers.

Results

DNA yield and library complexity were significantly lower in CNB specimens (both p < 0.01), whereas the insert size, sequencing depth, and Q30 ratio were similar between the matched specimens (all p > 0.05). The total numbers of genetic alternations detected in resection and CNB specimens were 186 and 211, respectively, with 156 alternations in common, yielding a specific concordance rate of 83.9%. The prevalence of mutations in 8 major driver genes was 100% identical between surgical and CNB specimens, though the allele frequency was lower in CNB specimens, with a median underestimation of 57%. Results of TMB were similar (p = 0.547) and MSI status was 100% matched in all paired specimens.

Conclusions

Pulmonary CNB specimens were suitable for NGS given the satisfactory accuracy when compared to corresponding surgical specimens. NGS results yielding from CNB specimens should be deemed reliable to provide instructive information for the treatment of advanced lung cancers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-022-01255-y.

Differentiating EGFR from ALK mutation status using radiomics signature based on MR sequences of brain metastasis

PURPOSE

More and more small brain metastases (BMs) in asymptomatic patients can be detected even prior to their primary lung cancer with the development of MRI. The aim of this study was to develop a predictive radiomics model to identify epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) mutation status in BM and explore the optimal MR sequence for predication.

METHODS

This retrospective study included 186 patients with proven BM of lung cancer (training cohort: 70 patients with EGFR mutations and 65 patients with ALK rearrangements; testing cohort: 26 patients with EGFR mutations and 25 patients with ALK rearrangements). Radiomics features were separately extracted from contrast-enhanced T1-weighted imaging (T1-CE), T2 fluid-attenuated inversion recovery (T2-FLAIR) and T2WI sequences. The model for three MR sequences were constructed using a random forest classifier. ROC curves were used to validate the capability of the models in the training and testing cohorts.

RESULTS

The AUCs of the T2-FLAIR model were significantly higher than those of the T1-CE model in training cohort (0.991 versus 0.954) and testing cohort (0.950 versus 0.867) and much higher than those of the T2WI model in training cohort (0.991 versus 0.880) and testing cohort (0.950 versus 0.731). Besides, the F1 scores of the T1-CE model were slightly higher than the T2-FLAIR model and much higher than the T2WI model in two cohorts.

CONCLUSION

T2-FLAIR and T1-CE radiomics models that can be used as noninvasive tools for identifying EGFR and ALK mutation status are helpful to guide therapeutic strategies.

EGFR analysis on scrapings from cytology smears in lung carcinoma, an effective alternative to testing on trucut biopsies

BACKGROUND

Lung carcinomas are a leading cause of cancer morbidity and mortality. Many cases present at an advanced stage of disease where definitive treatment by surgical resection is not feasible. Molecular testing using materials derived from minimally invasive procedures aid in targeted therapy with least iatrogenic burden to the patient.

METHODS

Cases diagnosed as non-small cell lung carcinoma (NSCLC) on cytology were included in the study. Scrapings from the smears with adequate tumor cell load were submitted for molecular testing. The DNA was extracted and quantified. Mutations in exons 18, 19, 20, and 21 of the EGFR gene were detected using Sanger sequencing. DNA quantity and EGFR mutation status on equal number of consecutive trucut biopsy specimens were also analyzed.

RESULTS

Seventy cases of NSCLC tested for EGFR mutation had a median DNA concentration of 40.2 ng/μl and 31% cases showed mutation. Majority of mutations (14/21, 66.66%) were identified in exon 19. Among 70 trucut biopsy samples, DNA concentration was 41.42 ng/μl and 30% cases showed mutation. No significant difference was seen in DNA quantity and EGFR mutation between cytology smears and trucut biopsies.

CONCLUSION

EGFR testing on cytology smears provides adequate DNA yield with minimal invasiveness and is equally effective as biopsies. Testing on samples like pleural effusion allows for concomitant diagnosis, staging, and molecular testing in one procedure. Tests done on the smears rather than on cell block or trucut biopsies ensures superior quality DNA from the tumor cells as they are unexposed to cross linking formalin fixative.

Feasibility of comprehensive genotyping specimens from radial endobronchial ultrasonography and electromagnetic navigation bronchoscopy

Introduction

Mini-invasive bronchoscopic techniques (such as radial endobronchial ultrasonography (rEBUS) and electromagnetic navigation (EMN)) have been developed to reach the peripheral lung but result in small samples. The feasibility of an adequate molecular testing from these specimens has been very little studied.

Methods

We retrospectively reviewed EMN and rEBUS procedures performed in patients diagnosed with lung cancer in our institution in 2017 and 2018. We analysed the sensitivity for rEBUS and EMN and each sampling method, and the feasibility of a comprehensive molecular testing.

Results

In total, 317 rEBUS and 14 EMN were performed. Median sizes of tumours were 16 and 32 mm for EMN and rEBUS, respectively. Overall sensitivity for rEBUS and EMN was 84.3%. Cytology was found to be complementary with biopsies, with 13.3% of cancer diagnosed on cytology while biopsies were negative. Complication rate was 2.4% (pneumothorax 1.5%, mild haemoptysis 0.9%). Genotyping (immunohistochemistry for ROS1 and ALK followed by fluorescence in situ hybridisation if positive and hybrid capture next-generation sequencing covering 48 genes), when ordered (n=188), was feasible in 69.1% (EGFR 17.7%, KRAS 31.7%, BRAF 4.8%, ALK 1.2%, MET 3.1%, HER2 0.8%). PD-L1 (programmed death-ligand 1) expression, when ordered (n=232), could be analysed in 94% of cases. Overall, 56.9% (33 out of 58) of patients for whom genotyping was not feasible underwent a second sampling (12 pretreatment, 21 at progression), allowing for the detection of six actionable genotypes (five EGFR, one MET).

Conclusion

rEBUS and EMN are sensitive and safe procedures that result in limited samples, often not suitable for genotyping, highlighting the importance of integrating liquid biopsy in routine testing.

Radial EBUS and EMN bronchoscopies are safe and sensitive procedures for lung cancer diagnosis. Cytology is highly complementary with histology. These small samples are, however, not suitable for an exhaustive molecular testing in 30% of cases.https://bit.ly/3eZ7Xn0

Advanced non-small cell lung cancer: Rapid evaluation of EGFR status on fine-needle cytology samples using Idylla

Advanced non-small cell lung cancer (NSCLC) needs to be managed rapidly; therefore, a rapid assessment of the epidermal growth factor receptor (EGFR) status is mandatory. Computed Tomography (CT)-guided or Ultrasound (US)-guided Fine-Needle Aspiration Cytology (FNAC) allows a rapid diagnosis of both primary and metastatic tumor through rapid on-site evaluation (ROSE) and the proper management of diagnostic material. Idylla (Biocartis, Mechelen, Belgium) is an automated RT-PCR system which evaluates the mutational status of specific genes in less than two hours. In this study, the EGFR mutational status in advanced NSCLC was analyzed on 28 FNAC samples with Idylla. After ROSE, residual FNAC material and/or additional passes were pipetted into the Idylla EGFR cartridge. Patients endorsed a consent form before carrying out the analysis. Results were controlled by pyrosequencing. Adequate EGFR status was obtained in 26/28 cases (22 wild type and 4 mutated). Mutated cases harbored EGFR Exon 19 deletion and L858R point mutation. In 2/28 cases the analysis failed. The combination of FNAC, ROSE and Idylla is a rapid, accurate and effective method that can be conveniently used to assess EGFR status in advanced NSCLC.

Predictive molecular pathology in the time of COVID-19

AIMS

In the time of COVID-19, predictive molecular pathology laboratories must still timely select oncological patients for targeted treatments. However, the need to respect social distancing measures may delay results generated by laboratory-developed tests based on sequential steps a long hands-on time. Laboratory workflows should now be simplified.

METHODS

The organisation of the University of Naples Federico II predictive pathology laboratory was assessed before (March-April 2019) and during (March-April 2020) the Italian lockdown.

RESULTS

The number of patients undergoing single or multiple biomarker testing was similar in 2019 (n=43) and in 2020 (n=45). Considering adequate samples for molecular testing, before the outbreak, next-generation sequencing was mostly used (35/42, 83.3%). Testing six genes had a reagent cost of €98/patient. Conversely, in 2020, almost all cases (38/41, 92.7%) were analysed by automated testing. This latter had for any single assay/gene a significant reagent cost (€95-€136) and a faster mean turnaround time (5.3 vs 7.9 working days).

CONCLUSION

In the times of coronavirus, laboratory fully automated platforms simplify predictive molecular testing. Laboratory staff may be more safely and cost-effectively managed.

Next generation sequencing in cytology

The application of next generation sequencing (NGS) technology to cytological samples has significantly modified molecular cytopathology practice. Cytological samples represent a valid source of high-quality DNA for NGS analysis, especially for predicting patients' response to targeted treatments and for refining the risk of malignancy in indeterminate cytological diagnoses. However, several pre-analytical factors may influence the reliability of NGS clinical analysis. Here, we briefly review the challenges of NGS in cytology practice, focusing on those pre-analytical factors that may negatively affect NGS success rates and routine diagnostic applications. Finally, we address the future directions of the field.

Dealing with NSCLC EGFR mutation testing and treatment: A comprehensive review with an Italian real-world perspective

Since their discovery, relevant efforts have been made to optimize the detection approaches to EGFR mutations as well as the clinical management of EGFR-mutated NSCLC. The recent shift from single gene testing to novel comprehensive detection platforms along with the development of new generation tyrosine kinase inhibitors, targeting both common and uncommon EGFR-mutations, is leading to a progressive increase in the number of patients who may benefit from targeted approaches, with subsequent impact on their long-term survival and quality of life. However, a prompt and adequate implementation of the most recent diagnostic and treatment advances in the routine practice often remains critical to be specifically addressed. In this review we provide a complete and updated overview of the different detection platforms and therapeutic options currently available for the clinical management of advanced EGFR-positive NSCLC, summarizing scientific evidence and describing molecular testing as well as treatment practice in the real-word scenario.

Performance evaluation of a fully closed real-time PCR platform for the detection of KRAS p.G12C mutations in liquid biopsy of patients with non-small cell lung cancer

Whenever tissue sample is not available, non-small cell lung cancer (NSCLC) biomarker testing is performed with liquid biopsy. The Kirsten rat sarcoma viral oncogene homolog (KRAS) p.G12C mutation is a novel target in patients with NSCLC. In this study, 33 NSCLC frozen plasma samples, previously characterised for KRAS mutational status by next generation sequencing (NGS), were processed by the fully automated Idylla KRAS assay. In 30/33 cases, archival matched cell-free DNA (cfDNA) was also directly pipetted in the cartridge. Overall, 30/33 plasma and 28/30 cfDNA samples yielded valid results. In 29/30 of KRAS p.G12C mutant plasma samples and 26/28 of cfDNA, Idylla confirmed the NGS results. In conclusion, the Idylla NSCLC KRAS liquid biopsy assay may represent a reliable tool to assess KRAS p.G12C mutation.

MRI radiomic signature predicts intracranial progression-free survival in patients with brain metastases of ALK-positive non-small cell lung cancer

Background

Intracranial progression is considered an important cause of treatment failure in anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) patients. Recent advances in targeted therapy and radiomics have generated considerable interest for the exploration of prognostic imaging biomarkers to predict the clinical course. Here, we developed a magnetic resonance imaging (MRI) radiomic signature that can stratify survival and intracranial progression.

Methods

We analyzed 87 brain metastatic lesions in 24 ALK-positive NSCLC patients undergoing ALK-inhibitor ensartinib therapy and divided them into training (n=61) and validation (n=26) sets. Radiomic features were extracted and screened from contrast-enhanced MR images. Combined with these selected features, the Rad-score was calculated with multivariate logistic regression. The predictive model and Rad-score performance were assessed in the training set and validated in the validation set; decision curve analysis was performed with the combined training and validation sets to estimate Rad-score’s patient-stratification ability.

Results

The prediction model constructed with nine selected radiomic features could predict intracranial progression within 51 weeks (AUC =0.84 and 0.85 in the training and validation sets, respectively), while clinical and regular MRI characteristics were independent of progression (P>0.05). The decision-curve analysis showed that the radiomic prediction model was clinically useful. The Kaplan-Meier analysis showed that the progression-free survival (PFS) difference between the high- and low-risk groups distinguished by the Rad-score was significant (P=0.017).

Conclusions

Radiomics may provide prognostic information and improve pretreatment risk stratification in ALK-positive NSCLC patients with brain metastases undergoing ensartinib treatment, allowing follow-up and treatment to be tailored to the patient’s individual risk profile.

Tumor mutational burden on cytological samples: A pilot study

BACKGROUND

Immune-checkpoint inhibitors (ICIs) represent an important treatment option for patients who have advanced stage non-small cell lung cancer (NSCLC). Currently, evaluation of the expression level of programmed death-ligand 1 (PD-L1) has proven highly successful as a positive predictive biomarker for ICIs. In addition to PD-L1, other promising predictive biomarkers are emerging, including high tumor mutational burden (TMB-H). However, measuring TMB-H remains challenging for several reasons, among which is the difficulty in obtaining adequate tissue material from NSCLC patients. There are no data in the current literature regarding the possibility of adopting cell blocks (CBs) for TMB evaluation; therefore, our goal was to evaluate the feasibility of analyzing TMB on CBs.

METHODS

For evaluation of differences in run metric parameters, 8 pairs of histological and CB samples from patients with NSCLC were analyzed using the Oncomine Tumor Mutational Load Assay on Ion Torrent S5 GS next-generation sequencing (NGS) platform.

RESULTS

Most CBs (6/8, 75.0%) were successfully analyzed by adopting the broad NGS panel approach. CBs provided results similar to those obtained on histological matched specimens in terms of median total reads (7207048.80 vs 7558817.80), median mapped reads (7075753.83 vs 7513822.00), median read lengths (115.50 vs. 113.00), median percentage of reads on-target (97.49% vs. 98.45%), median average reads per amplicon (454.67 vs 476.14), and median uniformity of amplicon coverage (83.52% vs 84.13%).

CONCLUSION

In this pilot study, we demonstrated the technical feasibility of assessing TMB on CBs.

Liquid biopsy for BRAF mutations testing in non-small cell lung cancer: a retrospective study

V-Raf murine sarcoma viral oncogene homolog B (BRAF) gene mutations have recently been approved to select advanced stages non-small cell lung cancer (NSCLC) patients for tyrosine kinase inhibitors treatments. In this setting, liquid biopsy may represent a valuable option for BRAF mutational testing in patients without tissue availability. Here, we reviewed 196 plasma based liquid biopsies analysed by an in-house developed next generation sequencing panel, termed SiRe. On the overall, 6 (3.1%) out of 196 BRAF mutated cases were identified, with an overall median allelic frequency of 3.4%. Exon 15 p.V600E was the most common detected mutation (2/6, 33.3%). Our data highlighted that the SiRe panel is a robust tool for BRAF mutation assessment on circulating tumour DNA. Further investigation is required to develop a diagnostic algorithm to harmonise BRAF testing on tissue and blood in advanced stages NSCLC patients.

Liquid Biopsy of Non-Plasma Body Fluids in Non-Small Cell Lung Cancer: Look Closer to the Tumor!

Liquid biopsy is a rapidly emerging field due to an increasing number of oncogenic drivers and a better understanding of resistance mechanisms to targeted therapies in non-small cell lung cancer (NSCLC). The sensitivity of the most widely used blood-based assays is, however, limited in particular in cases of low tumor volume where shed of tumor-derived material can be limited. A negative result thus requires biopsy confirmation using minimally invasive sampling procedures that can result in small specimens, which are often not suitable for genotyping. Liquid biopsy is not limited to plasma, and tumor DNA circulating in other body fluids such as urine, pleural fluid, cerebrospinal fluid, or cytology specimen-derived supernatant can be exploited. In comparison to cell blocks, these fluids in close contact to the tumor may contain a more abundant and less analytically demanding tumor DNA. In this review, we discuss the potential applications of circulating tumor DNA derived from cytology samples in NSCLC, from early stage (screening, nodule characterization) to metastatic disease.

Concomitant Rare KRAS and BRAF Mutations in Lung Adenocarcinoma: A Case Report

In July 2020, an active smoker, 63-year old man was admitted to the oncology unit of A.O.R.N. Sant’Anna e San Sebastiano (Caserta, Italy). Chest radiology highlighted right pleural effusion. Total-body CT scanning revealed a solid lesion with lobulated contours in the apical segment of the upper right lobe. The patient’s oncologist requested a molecular assessment of EGFR, ALK, ROS1, BRAF, and KRAS, as well as an evaluation of PD-L1 expression level. To this end, we carried out NGS analysis, on DNA extracted from cytospins, by adopting a custom-designed NGS panel (SiRe®). Overall, no actionable mutations in the tested genes were identified. Conversely, concomitant BRAF exon 11 p.G469A and a KRAS exon 4 p.A146T mutations were detected. Owing to the limited data on the presence of KRAS exon 4 p.A146T point mutation in lung adenocarcinoma patients, a further molecular confirmatory analysis was carried out with a dedicated KRAS cartridge on a fully automated real time polymerase chain reaction. When DNA was extracted from the TTF-1 positive tumor cell slide, the same KRAS alteration was observed. Unfortunately, the patient died in August 2020 before having the chance to start any type of treatment.

BRAF as a positive predictive biomarker: Focus on lung cancer and melanoma patients

In the era of personalized medicine, BRAF mutational assessment is mandatory in advanced-stage melanoma and non-small cell lung cancer (NSCLC) patients. The identification of actionable mutations is crucial for the adequate management of these patients. To date various drugs have been implemented in clinical practice. Similarly, various methods may be adopted for the identification of BRAF mutations. Here, we briefly review the current literature on BRAF in melanoma and NSCLC, focusing attention in particular on the different methods and drugs adopted in these patients. In addition, an overview of the real-world practice in different Italian laboratories with high expertise in molecular predictive pathology testing is provided.

KRAS mutations testing in non-small cell lung cancer: the role of Liquid biopsy in the basal setting

In advanced stage non-small cell lung cancer (NSCLC) patients, Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) testing may soon acquire a predictive significance to select patients for AMG510 treatment. Since tissue samples are not always available, liquid biopsy may represent a viable option for KRAS testing. Here, we review the last three years clinical practice performed on 194 plasma based liquid biopsies by next generation sequencing (NGS) SiRe^® panel. In particular, 36 (18.6%) KRAS mutated cases were identified, with an overall median allelic frequency of 5.0% (ranging between 0.2% and 46.8%). No concomitant mutations were observed in the other NSCLC clinical relevant genes included in the SiRe^® panel, such as epidermal growth factor receptor (EGFR) and v-Raf murine sarcoma viral oncogene homolog B (BRAF). Exon 2 p.G12C was the most common detected mutation (13/36, 36.1%). In conclusion, our data update and confirm that SiRe^® NGS panel represents a robust analytical tool to assess KRAS mutational status on circulating tumor DNA. Further investigation is required to design more cost-effective diagnostic algorithms to harmonize clinical relevant biomarker testing on tissue and blood in advanced stage NSCLC clinical practice.

Cytology meets next generation sequencing and liquid biopsy: A case of lung adenocarcinoma presenting as metastasis to the phalanx

Carcinomas do rarely metastasize to the finger. Non-small-cell lung cancer is most frequently involved. To date, only a few cases have been reported, on histology. Here we describe the cytological features of a metastatic lung adenocarcinoma case to the phalanx of the right forefinger as initial manifestation of the neoplastic disease in a 69-years-old woman. The cytological microscopic findings, complemented by a wide array of ancillary techniques, were confirmed by histology. Neoplastic cells were positive for cytokeratin 7 (CK7) and thyroid transcription factor 1 (TTF-1), harboring, in tissue and in bloodstream samples, an uncommon epidermal growth factor receptor (EGFR) exon 20 p.S768_D760DUP, detected by next generation sequencing (NGS) and liquid biopsy. Cytology corroborated by immunocytochemistry, NGS, and liquid biopsy is a modern approach to provide diagnostic and therapeutic information even in rare and challenging cases.

Current and future applications of liquid biopsy in nonsmall cell lung cancer from early to advanced stages

Liquid biopsy refers to the analysis of any tumour-derived material circulating in the blood or any other body fluid. This concept is particularly relevant in lung cancer as the tumour is often difficult to reach and may need an invasive and potentially harmful procedure. Moreover, the multitude of anticancer drugs and their sequential use underline the importance of conducting an iterative assessment of tumour biology. Liquid biopsies can noninvasively detect any targetable genomic alteration and guide corresponding targeted therapy, in addition to monitoring response to treatment and exploring the genetic changes at resistance, overcoming spatial and temporal heterogeneity.In this article, we review the available data in the field, which suggest the potential of liquid biopsy in the area of lung cancer, with a particular focus on cell-free DNA and circulating tumour cells. We discuss their respective applications in patient selection and monitoring through targeted therapy, as well as immune checkpoint inhibitors. The current data and future applications of liquid biopsy in the early stage setting are also investigated.Liquid biopsy has the potential to help manage nonsmall cell lung cancer throughout all stages of lung cancer: screening, minimal residual disease detection to guide adjuvant treatment, early detection of relapse, systemic treatment initiation and monitoring of response (targeted or immune therapy), and resistance genotyping.

Comparison between two different next generation sequencing platforms for clinical relevant gene mutation test in solid tumours

In the present study, we analysed 44 formalin fixed paraffin embedded (FFPE) from different solid tumours by adopting two different next generation sequencing platforms: GeneReader (QIAGEN, Hilden, Germany) and Ion Torrent (Thermo Fisher Scientific, Waltham, Massachusetts, USA). We highlighted a 100% concordance between the platforms. In addition, focusing on variant detection, we evaluated a very good agreement between the two tests (Cohen's kappa=0.84) and, when taking into account variant allele fraction value for each variant, a very high concordance was obtained (Pearson's r=0.94). Our results underlined the high performance rate of GeneReader on FFPE samples and its suitability in routine molecular predictive practice.

Is the Idylla EGFR Mutation Assay feasible on archival stained cytological smears? A pilot study

AIM

The rapid and fully automated Idylla EGFR Mutation Assay has been specifically designed to process formalin-fixed, paraffin-embedded sections without requiring preliminary DNA extraction. This study evaluates whether this approach can also process archival smears from patients with non-small cell lung cancer (NSCLC) by scraping the stained cellular material directly into the cartridge.

METHODS

The study was divided into two parts. In the first part, we carried out Idylla EGFR Mutation Assay on archival stained smears from 39 patients with NSCLC. Among these, 14 cases harboured a mutation in either exon 19 (n=11) or exon 21 (n=3), previously detected on DNA extracts by fragment length and TaqMan assays. In the second part, we evaluated whether de-staining of the smears could reduce background fluorescence.

RESULTS

The Idylla EGFR Mutation Assay confirmed the presence of EGFR mutation in 11 instances (78.6%). However, concordance was higher for exon 19 deletions (10/11) than for exon 21 p.L858R assessments. Raw data showed a high background fluorescence in channel 2, where the EGFR exon 21 p.L858R mutation was detected. This interference, due to dye residues from the original staining, was partially reduced by de-staining the cytological material.

CONCLUSIONS

Our data, although preliminary, show that the Idylla EGFR Mutation Assay can reliably process most archival smears without requiring preliminary DNA extraction. Results may be further improved by de-staining the cellular material before insertion into the cartridge.

Role of Cytomorphology in the Era of Liquid Biopsy

In the late stages of non-small cell lung cancer, the detection of sensitizing mutations of the epidermal growth factor receptor (EGFR) is mandatory to select patients' treatment with first- or second-generation tyrosine kinase inhibitors (TKIs). In patients showing progressive disease, the assessment of the EGFR exon 20 resistance point mutation p.T790M is required for third-generation TKI administration. However, molecular analysis does not capture all the different mechanisms of resistance against these molecules. A variety of morphological changes associated with acquired resistance have also been described. Since an altered morphology may be the only clue to acquired resistance, cytopathology still plays a relevant role in this setting. In this comprehensive review, we have focused on the relevance of squamous cell carcinoma, small cell lung cancer and large-cell neuroendocrine carcinoma transitions from adenocarcinoma resistant to TKIs.

EGFR exon 19 deletion switch and development of p.L792Q mutation as a new resistance mechanism to osimertinib: a case report and literature review

Epidermal growth factor receptor (EGFR) gene mutations play an important role in the treatment management of non-small cell lung cancer (NSCLC) patients. After a first- or second-generation EGFR tyrosine kinase inhibitor (TKI) therapy, the most common resistance mechanism involves the selection of a resistant clone carrying the exon 20 p.T790M point mutation. However, also for these patients, treated with a third-generation TKI (osimertinib) several mechanisms of acquired resistance are described. Here we report the case of a 68-year-old man with an EGFR exon 19 deletion treated with gefitinib in first line and osimertinib in second line besides on the presence of a p.T790M mutation, who developed an uncommon EGFR exon 20 p.L792Q point mutation at the progression to osimertinib, with the concomitant modification of the original sensitizing EGFR exon 19 deletion and the loss of p.T790M mutation.

Liquid Biopsy and Lung Cancer

The identification of non-small cell lung cancer (NSCLC) patients potentially responsive to targeted therapies relies on a number of relevant biomarkers, including EGFR, ALK, ROS-1, and PD-L1. Biomarker identification is most commonly based on surgical sample collection. However, when tissues are difficult to reach or when multiple analyses are necessary to monitor tumor progression and treatment response, liquid biopsy is a valid noninvasive alternative. This analysis, which is preferentially performed on circulating tumor DNA (ctDNA) extracted from plasma samples, has the major advantage of reducing the inherent risks and discomfort of tissue biopsy. However, a major disadvantage is that it yields only a low number of ctDNA targets. Thus, to avoid false-positive and false-negative results, it is important to adopt and validate technologies with high sensitivity and specificity in the pre-analytical phase of sampling. This review succinctly addresses the principal methodologies for analyzing plasma-derived ctDNA in NSCLC patients.

Liquid biopsy of fine-needle aspiration supernatant for lung cancer genotyping

BACKGROUND

Tumor genotyping is transforming lung cancer care but requires adequate tumor tissue. Advances in minimally invasive biopsy techniques have increased access to difficult-to-access lesions, but often result in smaller samples. With the advent of highly sensitive DNA genotyping methods used for plasma analysis, we hypothesized that these same methods might allow genotyping of free DNA derived from fine needle aspiration supernatant (FNA-S).

METHODS

We studied patients with known or suspected lung cancer undergoing fine needle aspirate (FNA). After spinning the sample for cellblock, the FNA-S (usually discarded) was saved for genotyping. Supernatant cell-free DNA (SN-cfDNA) was extracted and tested by both droplet digital PCR (EGFR, BRAF, KRAS mutations) and highly sensitive amplicon-based next-generation sequencing (NGS).

RESULTS

17 samples were studied, including 11 FNAs from patients with suspected lung cancer and 6 FNAs from patients with lung cancer and acquired drug resistance. Of 6 newly diagnosed adenocarcinomas, 4 had a driver mutations (1 EGFR, 2 KRAS, 1 HER2) found on tissue; all of these could be detected in SN-cfDNA. The EGFR driver mutation was detected in all 5 adenocarcinomas with acquired EGFR resistance and the EGFR T790 M in three cases, in agreement with cellblock.

CONCLUSIONS

FNA-S is a rich source of fresh tumor DNA, potentially increasing the diagnostic yield from small FNAs. Through use of emerging techniques for highly sensitive genotyping, this widely available biospecimen has potential for facilitating rapid cancer genotyping at diagnosis and after drug resistance.

Molecular Pathology of Lung Cancer Cytology Specimens: A Concise Review

CONTEXT

- There has been a paradigm shift in the understanding of molecular pathogenesis of lung cancer. A number of oncogenic drivers have been identified in non-small cell lung carcinoma, such as the epidermal growth factor receptor ( EGFR) mutation and anaplastic lymphoma kinase ( ALK) gene rearrangement. Because of the clinical presentation at an advanced stage of disease in non-small cell lung carcinoma patients, the use of minimally invasive techniques is preferred to obtain a tumor sample for diagnosis. These techniques include image-guided biopsies and fine-needle aspirations, and frequently the cytology specimen may be the only tissue sample available for the diagnosis and molecular testing for these patients.

OBJECTIVE

- To review the current literature and evaluate the role of cytology specimens in lung cancer mutation testing. We reviewed the types of specimens received in the laboratory, specimen processing, the effect of preanalytic factors on downstream molecular studies, and the commonly used molecular techniques for biomarker testing in lung cancer.

DATA SOURCES

- PubMed and Google search engines were used to review the published literature on the topic.

CONCLUSIONS

- Mutation testing is feasible on a variety of cytologic specimen types and preparations. However, a thorough understanding of the cytology workflow for the processing of samples and appropriate background knowledge of the molecular tests are necessary for triaging, and optimum use of these specimens is necessary to guide patient management.

Cell free DNA analysis by SiRe® next generation sequencing panel in non small cell lung cancer patients: focus on basal setting

Background

Non small cell lung cancer (NSCLC) is diagnosed in most cases on small tissue samples, such as cytological preparations and histological biopsies; these limited tissue specimens may be not always sufficient for testing epidermal growth factor receptor (EGFR) mutations and other relevant predictive biomarkers. Cell-free DNA (cfDNA) can be used as a surrogate for EGFR mutational testing, whenever tissue is unavailable. However, the detection of gene mutations on cfDNA is challenging; in fact, the extremely low concentration of circulating tumor DNA requires the implementation of highly sensitive and validated next generation techniques.

Methods

Thus, we have recently validated a novel next generation sequencing (NGS) assay, employing the SiRe^® gene panel to detect on cfDNA mutations of EGFR and KRAS, NRAS, BRAF, cKIT and PDGFR genes. In this current study, we report on a series of NSCLC patients, without available tissue for EGFR testing, who prospectively underwent SiRe^® NGS analysis.

Results

The results confirm the high clinical performance, in terms of success rate and mutation detection, of NGS based analysis of cfDNA.

Conclusions

SiRe^® NGS panel represent an effective diagnostic tool in cfDNA analysis setting.

Preanalytic specimen triage: Smears, cell blocks, cytospin preparations, transport media, and cytobanking

With increasing requests for the evaluation of prognostic and predictive molecular biomarkers, great attention must be paid to the preanalytical issues regarding sample quality and DNA/RNA yield from all different types of cytological preparations. The objectives of this review were: 1) to provide an update regarding the importance of specimen triage as well as specimen handling and collection; 2) to discuss the different cell preparations that can be used for molecular testing, their advantages and limitations; and 3) to highlight the strategies for biobanking cytology samples. Good-quality DNA/RNA can be harvested from fresh cells in cell suspensions, formalin-fixed paraffin-embedded cell blocks, archival stained smears, archival unstained cytospin preparations, liquid-based cytology slides, FTA cards, and cryopreserved cells. In contrast to formalin-fixed paraffin-embedded tissue specimens (small biopsies and surgical resections), the multitude of types of sample preparations as well as the diversity in sample collection and processing procedures make cytology an ideal specimen for most genomic platforms, with less DNA and RNA degradation and a purer sample, usually with a higher concentration of tumor cells. The broad incorporation of cytological specimens into clinical practice. A should increase the number of samples potentially available for molecular tests and avoid repeat invasive procedures for tissue procurement, thereby increasing patient safety. In this context, it is of utmost importance that cytopathologists become familiar with the variables that can affect test results and embrace the goal of excellence in sample quality. Cancer Cytopathol 2017;125(6 suppl):455-64. © 2017 American Cancer Society.

Plasma genotyping in patients with non-small-cell lung cancer: simplifying or confusing the diagnosis?

The identification of driver mutations in patients with advanced non-small-cell lung cancer has changed the treatment outcomes for patients with actionable driver mutations. Lack of tissue at diagnosis, however, remains a central obstacle in making optimal treatment decisions in patients with advanced disease. Although the US FDA has approved one plasma-based test for detecting epidermal growth factor receptor mutations in patients with advanced stage disease, sensitivity of these assays remains mediocre, necessitating additional tissue testing and possible delays in patients with negative results. Serial monitoring for response and early detection of acquired resistance to targeted therapies is also possible with cell-free DNA, however the benefit of switching therapy prior to detection of changes on imaging is unknown currently.

Simple multiplexed PCR-based barcoding of DNA for ultrasensitive mutation detection by next-generation sequencing

Detection of extremely rare variant alleles within a complex mixture of DNA molecules is becoming increasingly relevant in many areas of clinical and basic research, such as the detection of circulating tumor DNA in the plasma of cancer patients. Barcoding of DNA template molecules early in next-generation sequencing (NGS) library construction provides a way to identify and bioinformatically remove polymerase errors that otherwise make detection of these rare variants very difficult. Several barcoding strategies have been reported, but all require long and complex library preparation protocols. Simple, multiplexed, PCR-based barcoding of DNA for sensitive mutation detection using sequencing (SiMSen-seq) was developed to generate targeted barcoded libraries with minimal DNA input, flexible target selection and a very simple, short (∼4 h) library construction protocol. The protocol comprises a three-cycle barcoding PCR step followed directly by adaptor PCR to generate the library and then bead purification before sequencing. Thus, SiMSen-seq allows detection of variant alleles at <0.1% frequency with easy customization of library content (from 1 to 40+ PCR amplicons) and a protocol that can be implemented in any molecular biology laboratory. Here, we provide a detailed protocol for assay development and describe software to process the barcoded sequence reads.

Profile of the Roche cobas® EGFR mutation test v2 for non-small cell lung cancer

INTRODUCTION

The discovery of driver mutations in non-small cell lung cancer (NSCLC) has led to the development of genome-based personalized medicine. Fifteen to 20% of adenocarcinomas harbor an epidermal growth factor receptor (EGFR) activating mutation associated with responses to EGFR tyrosine kinase inhibitors (TKIs). Individual laboratories' expertise and the availability of appropriate equipment are valuable assets in predictive molecular pathology, although the choice of methods should be determined by the nature of the samples to be tested and whether the detection of only well-characterized EGFR mutations or rather, of all detectable mutations, is required. Areas covered: The EGFR mutation testing landscape is manifold and includes both screening and targeted methods, each with their own pros and cons. Here we review one of these companion tests, the Roche cobas® EGFR mutation test v2, from a methodological point of view, also exploring its liquid-biopsy applications. Expert commentary: The Roche cobas® EGFR mutation test v2, based on real time RT-PCR, is a reliable option for testing EGFR mutations in clinical practice, either using tissue-derived DNA or plasma-derived cfDNA. This application will be valuable for laboratories with whose purpose is purely diagnostic and lacking high-throughput technologies.

Development of a gene panel for next-generation sequencing of clinically relevant mutations in cell-free DNA from cancer patients

Background:

When tumour tissue is unavailable, cell-free DNA (cfDNA)can serve as a surrogate for genetic analyses. Because mutated alleles in cfDNA are usually below 1%, next-generation sequencing (NGS)must be narrowed to target only clinically relevant genes. In this proof-of-concept study, we developed a panel to use in ultra-deep sequencing to identify such mutations in cfDNA.

Methods:

Our panel (‘SiRe') covers 568 mutations in six genes (EGFR, KRAS, NRAS, BRAF, cKIT and PDGFRα)involved in non-small-cell lung cancer (NSCLC), gastrointestinal stromal tumour, colorectal carcinoma and melanoma. We evaluated the panel performance in three steps. First, we analysed its analytical sensitivity on cell line DNA and by using an artificial reference standard with multiple mutations in different genes. Second, we analysed cfDNA from cancer patients at presentation (n=42), treatment response (n=12) and tumour progression (n=11); all patients had paired tumour tissue and cfDNA previously genotyped with a Taqman-derived assay (TDA). Third, we tested blood samples prospectively collected from NSCLC patients (n=79) to assess the performance of SiRe in clinical practice.

Results:

SiRe had a high analytical performance and a 0.01% lower limit of detection. In the retrospective series, SiRe detected 40 EGFR, 11 KRAS, 1 NRAS and 5 BRAF mutations (96.8% concordance with TDA). In the baseline samples, SiRe had 100% specificity and 79% sensitivity relative to tumour tissue. Finally, in the prospective series, SiRe detected 8.7% (4/46) of EGFR mutations at baseline and 42.9% (9/21) of EGFR p.T790M in patients at tumour progression.

Conclusions:

SiRe is a feasible NGS panel for cfDNA analysis in clinical practice.

Next generation sequencing techniques in liquid biopsy: focus on non-small cell lung cancer patients

The advent of genomic based personalized medicine has led to multiple advances in the molecular characterization of many tumor types, such as non-small cell lung cancer (NSCLC). NSCLC is diagnosed in most cases on small tissue samples that may be not always sufficient for EGFR mutational assessment to select patients for first and second generations' tyrosine kinase inhibitors (TKIs) therapy. In patients without tissue availability at presentation, the analysis of cell free DNA (cfDNA) derived from liquid biopsy samples, in particular from plasma, represent an established alternative to provide EGFR mutational testing for treatment decision making. In addition, a new paradigm for TKIs resistance management was recently approved by Food and Drug Administration, supporting the liquid biopsy based genotyping prior to tissue based genotyping for the detection of T790M mutation to select patients for third generation TKIs. In these settings, real time PCR (RT-PCR) and digital PCR 'targeted' methods, which detect known mutations by specific probes, have extensively been adopted. Taking into account the restricted reference range and the limited multiplexing power of these targeted methods, the performance of liquid biopsy analyses may be further improved by next generation sequencing (NGS). While most tissue based NGS genotyping is well established, liquid biopsy NGS application is challenging, requiring a careful validation of the whole process, from blood collection to variant calling. Here we review this evolving field, highlighting those methodological points that are crucial to accurately select NSCLC patients for TKIs treatment administration by NGS on cfDNA.

Utilization of ancillary studies in the cytologic diagnosis of respiratory lesions: The papanicolaou society of cytopathology consensus recommendations for respiratory cytology

The Papanicolaou Society of Cytopathology has developed a set of guidelines for respiratory cytology including indications for sputum examination, bronchial washings and brushings, CT-guided FNA and endobronchial ultrasound guided fine needle aspiration (EBUS-FNA), as well as recommendations for classification and criteria, ancillary testing and post-cytologic diagnosis management and follow-up. All recommendation documents are based on the expertise of committee members, an extensive literature review, and feedback from presentations at national and international conferences. The guideline documents selectively present the results of these discussions. The present document summarizes recommendations for ancillary testing of cytologic samples. Ancillary testing including microbiologic, immunocytochemical, flow cytometric, and molecular testing, including next-generation sequencing are discussed. Diagn. Cytopathol. 2016;44:1000-1009. © 2016 Wiley Periodicals, Inc.

EGFR mutation detection on lung cancer cytological specimens by the novel fully automated PCR-based Idylla EGFR Mutation Assay

AIMS

In everyday practice, epidermal growth factor receptor (EGFR) testing is centralised in referral laboratories that receive paucicellular cytological specimens. Ideally, EGFR testing should be carried out in the centre where the patient is diagnosed such that the most cellular slide can be selected from in-house collected cytological material. However, available techniques are little standardised and difficult to be implemented in settings with little expertise in molecular testing. The Idylla EGFR prototype assay is a rapid and fully automated test which may easily be adopted by a wider number of pathological centres. This study assessed whether an Idylla EGFR prototype assay can be reliably applied to cytological lung cancer specimens.

METHODS

The limit of detection (LOD) of the Idylla EGFR prototype assay was assessed by cell line dilution studies. A total of 10 ng was directly placed inside an Idylla EGFR prototype assay cartridge. Idylla results were compared with fragment length (exon 19 del) and Taqman assays.

RESULTS

The Idylla EGFR prototype assay showed an LOD of 1% mutant allele and yielded valid results in 74/76 (97.3%) samples, detecting all the mutant cases (n=32) identified by standard techniques; in addition, Idylla detected two low abundance EGFR exon 19 deletions and two G719X exon 18 point mutations, not covered by our standard reference method.

CONCLUSIONS

Idylla EGFR prototype assay is sensitive on extracted DNA and can reliably be applied on cytological samples, enabling implementation of EGFR testing even in less experienced diagnostic units.

Biomarker Testing in Lung Carcinoma Cytology Specimens: A Perspective From Members of the Pulmonary Pathology Society

The advent of targeted therapy in lung cancer has heralded a paradigm shift in the practice of cytopathology with the need for accurately subtyping lung carcinoma, as well as providing adequate material for molecular studies, to help guide clinical and therapeutic decisions. The variety and versatility of cytologic-specimen preparations offer significant advantages to molecular testing; however, they frequently remain underused. Therefore, evaluating the utility and adequacy of cytologic specimens is critical, not only from a lung cancer diagnosis standpoint but also for the myriad ancillary studies that are necessary to provide appropriate clinical management. A large fraction of lung cancers are diagnosed by aspiration or exfoliative cytology specimens, and thus, optimizing strategies to triage and best use the tissue for diagnosis and biomarker studies forms a critical component of lung cancer management. This review focuses on the opportunities and challenges of using cytologic specimens for molecular diagnosis of lung cancer and the role of cytopathology in the molecular era.

EGFR mutation detection on routine cytological smears of non-small cell lung cancer by digital PCR: a validation study

Highly sensitive genotyping techniques are useful to detect epidermal growth factor receptor (EGFR) mutations on lung cancer cytological samples, when these specimens feature only few neoplastic cells. This study aimed to validate digital PCR (dPCR) methodology on cytological material. In plasmid model system, dPCR allowed for the detection of a minimal percentage (1%) of EGFR mutant alleles. Cytological samples (n = 30), with neoplastic cell percentage ranging from 10% to 80% and yielding a quantity of extracted DNA ranging from 1.75 to 60 ng/µL were selected. Results previously generated by fragment length and TaqMan assays (n = 8 exon 19 deletions, n = 2 L858R mutations and n = 20 wild-type DNA) were compared with those obtained by dPCR. Data were highly concordant (96.6%). However, dPCR detected an additional L858R mutation that had been missed by TaqMan assay on a paucicellular smear. This mutation was confirmed by cloning PCR products and sequencing. Thus, dPCR can reliably be used to increase EGFR mutation detection rate on scarcely cellular lung cancer smears.

Recent advances in the pathology and molecular genetics of lung cancer: A practical review for cytopathologists

Lung cancer is one of the most common causes of cancer-related death worldwide. Better understanding of the molecular genetic characteristics of non-small cell lung carcinoma (NSCLC), particularly adenocarcinoma, has opened the opportunity for targeted therapies. With the different molecular abnormalities and the different responses to new targeted therapies based on the histological subtype of NSCLC, there came a need to further classify NSCLC into squamous cell carcinoma and adenocarcinoma, and to perform the appropriate molecular testing in these different subtypes to guide management decisions. Given that approximately 70% of lung cancer patients have only small biopsies or cytology specimens available, incorporating the testing of these specimens into the cytopathology laboratory has been crucial. Herein, we review current concepts and recommendations on NSCLC subtyping and molecular testing that are relevant for the cytopathology community.

ALK gene expression status in pleural effusion predicts tumor responsiveness to crizotinib in Chinese patients with lung adenocarcinoma

Objective

The relationship between anaplastic lymphoma kinase (ALK) expression in malignant pleural effusion (MPE) samples detected only by Ventana immunohistochemistry (IHC) ALK (D5F3) and the efficacy of ALK-tyrosine kinase inhibitor therapy is uncertain.

Methods

Ventana anti-ALK (D5F3) rabbit monoclonal primary antibody testing was performed on 313 cell blocks of MPE samples from Chinese patients with advanced lung adenocarcinoma, and fluorescence in situ hybridization (FISH) was used to verify the ALK gene status in Ventana IHC ALK (D5F3)-positive samples. The follow-up clinical data on patients who received crizotinib treatment were recorded.

Results

Of the 313 MPE samples, 27 (8.6%) were confirmed as ALK expression-positive, and the Ventana IHC ALK (D5F3)-positive rate was 17.3% (27/156) in wild-type epidermal growth factor receptor (EGFR) MPE samples. Twenty-three of the 27 IHC ALK (D5F3)-positive samples were positive by FISH. Of the 11 Ventana IHC ALK (D5F3)-positive patients who received crizotinib therapy, 2 patients had complete response (CR), 5 had partial response (PR) and 3 had stable disease (SD).

Conclusions

The ALK gene expression status detected by the Ventana IHC ALK (D5F3) platform in MPE samples may predict tumor responsiveness to crizotinib in Chinese patients with advanced lung adenocarcinoma.

Preanalytic parameters in epidermal growth factor receptor mutation testing for non-small cell lung carcinoma: A review of cytologic series

The results from molecular assays can be affected significantly by the preanalytic condition of cytologic samples. The authors review current knowledge on the use of cytologic samples for epidermal growth factor receptor (EGFR) mutation testing in non–small cell lung cancer with a focus on preanalytic parameters. A systematic electronic search of the MEDLINE database was performed to identify original articles that reported the use of cytologic samples for EGFR molecular analysis and included a minimum of 100 samples. The information collected included author(s), journal, and year of publication; number of patients and samples; sampling method; type of preparation; type of fixative; staining techniques; mutation analysis techniques; tumor cellularity; the percentage of tumor cells; data on DNA quantity, quality, and concentration; failed assays; and the mutation rate. EGFR mutation analysis was conducted on 4999 cytologic samples from 22 studies that fulfilled the inclusion criteria. Fine‐needle aspirates and pleural effusions were the most common types of specimens used. DNA was mainly extracted from cell blocks and smears, and the most commonly reported fixatives included formalin, ethanol, and CytoLyt. Cellularity assessments and DNA yields were available from 5 studies each. The average success rate for the assays that used cytologic specimens was 95.87% (range, 85.2%‐100%). The mutation rate ranged from 6% to 50.46%, and a higher mutation detection rate and lower numbers of insufficient cases were reported for pleural effusions and lymph node samples from endobronchial ultrasound‐guided transbronchial needle aspiration compared with histologic specimens. Low cellularity and a low percentage of tumor cells were associated with higher test failure rates. Future guidelines should consider the current data for specific recommendations regarding cytologic samples. Cancer (Cancer Cytopathol) 2015;123:633–643. © 2015 American Cancer Society.

Preanalytic parameters for epidermal growth factor receptor mutation testing are reviewed in non–small cell lung cancer using 4999 cytologic samples from 22 studies. A higher mutation detection rate and lower numbers of insufficient cases are observed for pleural effusions and lymph node samples obtained using endobronchial ultrasound‐guided transbronchial needle aspiration compared with histologic specimens, and low cellularity and a lower percentage of tumor cells are associated with higher test failure rates. Future guidelines should consider the current data for specific recommendations regarding cytologic samples.