Effusion Immunocytochemistry as an Alternative Approach for the Selection of First-Line Targeted Therapy in Advanced Lung Adenocarcinoma

Insights into fourth generation selective inhibitors of (C797S) EGFR mutation combating non-small cell lung cancer resistance: a critical review

Lung cancer is the second most common cause of morbidity and mortality among cancer types worldwide, with non-small cell lung cancer (NSCLC) representing the majority of most cases. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) are among the most commonly used targeted therapy to treat NSCLC. Recent years have seen the evaluation of many synthetic EGFR TKIs, most of which showed therapeutic activity in pertinent models and were classified as first, second, and third-generation. The latest studies have concluded that their efficacy was also compromised by additional acquired mutations, including C797S. Because second- and third-generation EGFR TKIs are irreversible inhibitors, they are ineffective against C797S containing EGFR triple mutations (Del19/T790M/C797S and L858R/T790M/C797S). Therefore, there is an urgent unmet medical need to develop next-generation EGFR TKIs that selectively inhibit EGFR triple mutations via a non-irreversible mechanism. This review covers the fourth-generation EGFR-TKIs' most recent design with their essential binding interactions, the clinical difficulties, and the potential outcomes of treating patients with EGFR mutation C797S resistant to third-generation EGFR-TKIs was also discussed. Moreover, the utilization of various therapeutic strategies, including multi-targeting drugs and combination therapies, has also been reviewed.

Transthoracic sonographic scores in evaluating the success of different scelerosing modalities in patients with malignant pleural effusion

Background

Malignant pleural effusions (MPE) mostly arises from metastases to the pleura from other sites. Management of malignant effusions aims to palliate dyspnea and prevent the reaccumulation of pleural fluid to improve patients’ quality of life. Pleurodesis is the most common palliative treatment for patients with refractory MPE. This study was carried out to evaluate the performance of transthoracic sonographic (TUS) scores (pleural sliding and pleural adherence score) in predicting the success of pleurodesis by different modalities in patients with malignant pleural effusion. One hundred malignant pleural effusion patients were enrolled to an interventional clinical trial from September 2019 to April 2021 for palliative management of dyspnea. Pleurodesis for palliative treatment of dyspnea was done either spontaneously by the intercostal chest tube or by a sclerosing agent such as tetracycline solution or tetracycline poudrage or iodopovidine. Patients were randomly allocated to one of these four groups where each group included 25 patients. Transthoracic ultrasound was performed at baseline, and 1 month after pleurodesis and the lung sliding score and pleural adherence score were evaluated.

Results

Majority of patients (78%) had high baseline lung sliding score (7-8). Post pleurodesis only 11.4% had high scores (p<0.001), also the mean lung sliding score decreased significantly in comparison to the baseline values (p˂ 0.001) in the spontaneous, tetracycline solution, tetracycline poudrage, and iodopovidine groups (7.04 ± 1.02 vs. 4.85 ± 1.60, 7.28± 0.98 vs. 4.48± 1.75, 7.20±0.96 vs. 4.44 ± 1.45, 7.04±0.93 vs. 3.35±1.81, respectively). Iodopovidine pleurodesis group in comparison to the other modalities showed the highest pleural adherence score (12.64 ± 2.98) and absent lung sliding in 72.7% of cases and 70 % success rate. Pleural adherence score at cut off ≥ 12 showed 92.75% sensitivity, 89.47% specificity, 92.1 accuracy, and 0.911 area under the curve (AUC) for predicting successful pleurodesis.

Conclusion

TUS scores is a feasible, bedside, and accurate method to detect the outcome of pleurodesis. Iodopovidone was more effective than tetracycline solution, tetracycline poudrage, and spontaneous pleurodesis.

Trial registration

ClinicalTrials.gov. NCT04074902. Registered on 29 August 2019

Adequacy of pleural fluid cytology for comprehensive molecular analysis of lung adenocarcinoma: Experience of a large health-care system

Objectives:

Pleural fluid evaluation is an effective modality for identifying actionable genetic mutations to guide therapy in lung carcinoma. Clinicians requesting molecular studies often send large volumes of fluid to be processed that is not possible or cost effective and is hence not standard of practice in most cytopathology laboratories. We wanted to establish the characteristics of an adequate specimen that would yield reliable results with current molecular testing platforms.

Material and Methods:

A review of 500 malignant pleural effusions, from pulmonary and non-pulmonary sources, was undertaken over a 4-year period. Of these 44 cases (from 42 patients) that were positive for primary lung adenocarcinoma were included in the study. Molecular analysis was performed on 42 specimens. A complete next generation sequencing (NGS) panel was performed on 36 specimens. Individual testing for estimated glomerular filtration rate, KRAS, anaplastic lymphoma kinase, and ROS1 was performed on six specimens. The number of malignant cells and proportion of tumor to non-tumor nucleated cells (T: NT) on cell blocks was recorded as <20%, 20–50% and >50%.

Results:

The minimum volume on which a complete NGS panel could be performed was 20 ml with cell count of 1000 and T: NT proportion of 20–50%. The minimum number of tumor cells required for successful molecular analysis for T: NT proportion of <20%, 20–50%, and >50% was 300, 250, and 170 cells, respectively.

Conclusion:

We concluded that tumor cell proportion, rather than specimen volume, is of prime importance for determining the efficacy of pleural fluid for molecular studies. Evaluation of both absolute and relative numbers of tumor cells is critical for assessing the adequacy and predicting successful yield for molecular analysis.

Bronchial brushing cytology is comparable to bronchial biopsy for epidermal growth factor receptor mutation test in non-small cell lung cancer

Objectives:

Bronchial brushing (BB) is often used to obtain supplementary samples for diagnosing lung cancer. We examined the possibility of epidermal growth factor receptor (EGFR) testing on BB samples and compared them with bronchial biopsy samples.

Material and Methods:

We used 150 BB samples with non-small cell carcinoma submitted to our department within 2 years. Biopsy samples were concurrently submitted for histologic diagnosis. We used the peptide nucleic acid clamping method for EFGR mutation test. Histologic diagnosis identified 137 cases of adenocarcinomas and 13 cases of non-small cell lung carcinoma, not otherwise specified. Each sample was assessed for adequacy and DNA content for EGFR mutation test.

Results:

Among BB samples, 28 had exon 19 deletion, 21 had mutations in exon 21, 99 were wild type, and analysis of two failed. The EGFR mutation rate in BB samples was 33.1% (49/148). Among bronchial biopsy samples, 26 had exon 19 deletion, 20 had mutations in exon 21, 92 were wild type, and analysis of 12 failed. The EGFR mutation rate using biopsy sample was 33.8% (46/136). The mutation detection results were nearly identical in both groups of samples (131/138, 94.9%). However, in two cases, an exon 21 mZutation was detected in biopsy samples but not in BB samples. In five cases, exon 19 deletion (two cases) and exon 21 mutation (three cases) were detected in BB but not in biopsy samples. The median DNA content was 58.83 ng for BB samples and 48.47 ng for biopsy samples. The failure rate for BB samples was lower than for biopsy samples. Overall, the BB samples were comparable to bronchial biopsy samples in terms of DNA quantity and mutation detection results.

Conclusion:

We conclude that in case of inadequate biopsy samples, BB samples can be used as a substitute material for EGFR mutation test.

Outcome of ultrasound-guided, single session pleurodesis in malignant pleural effusion

Background

Chemical pleurodesis is frequently indicated to relieve symptoms imposed by large/recurrent malignant pleural effusion (MPE). Traditionally, a drain is left in the pleural space till the cessation of fluid accumulation before pleurodesis. Chest ultrasound can detect an amount of pleural fluid as less as 50 ml and can confirm apposition of the pleural surfaces which is required for successful pleurodesis. This work assessed the efficiency and safety of ultrasound-guided, single-session pleurodesis in cases with MPE.

Results

Seventeen of the patients completed a 2-month follow-up. The technique demonstrated a high success rate (88.2%). The mean duration from the start of pleural drainage till pleurodesis was 1.65 ± 0.70 h ranging from 1 to 3 h. A duration of 2.5 h or less was statistically proposed as a cutoff value not to exceed to predict success (sensitivity 100%, specificity 100%). The mean time for total hospital stay related to pleurodesis was 9.88 ± 3.12 h (range 4–12 h). No complications attributed to the procedure were recorded. Pleural Adherence Score and Absent Sliding Score (ASS) had a highly statistically significant correlation (p value < 0.001).

Conclusions

An ultrasound-guided completion of the process of pleurodesis in a single session with a shorter duration of pleural fluid drainage and shorter hospital stay (can be done on a day-care basis) is efficient, safe, and cost-effective. This technique is strongly recommended to replace the traditional practice of keeping the indwelling pleural drain for several days waiting for the cessation of pleural fluid reaccumulation. An ultrasound-derived ASS can be used as early as day 1 and day 15 to confirm pleural adherence and to expect the outcome of pleurodesis.

Immunocytochemistry for predictive biomarker testing in lung cancer cytology

With an escalating number of predictive biomarkers emerging in non-small cell lung carcinoma (NSCLC), immunohistochemistry (IHC) is being used as a rapid and cost-effective tool for the screening and detection of many of these markers. In particular, robust IHC assays performed on formalin-fixed, paraffin-embedded (FFPE) tumor tissue are widely used as surrogate markers for ALK and ROS1 rearrangements and for detecting programmed death ligand 1 (PD-L1) expression in patients with advanced NSCLC; in addition, they have become essential for treatment decisions. Cytology samples represent the only source of tumor in a significant proportion of patients with inoperable NSCLC, and there is increasing demand for predictive biomarker testing on them. However, the wide variation in the types of cytology samples and their preparatory methods, the use of alcohol-based fixatives that interfere with immunochemistry results, the difficulty in procurement of cytology-specific controls, and the uncertainty regarding test validity have resulted in underutilization of cytology material for predictive immunocytochemistry (ICC), and most cytopathologists limit such testing to FFPE cell blocks (CBs). The purpose of this review is to: 1) analyze various preanalytical, analytical, and postanalytical factors influencing ICC results; 2) discuss measures for validation of ICC protocols; and 3) summarize published data on predictive ICC for ALK, ROS1, EGFR gene alterations and PD-L1 expression on lung cancer cytology. Based on our experience and from a review of the literature, we conclude that cytology specimens are in principal suitable for predictive ICC, but proper optimization and rigorous quality control for high-quality staining are essential, particularly for non-CB preparations.

[Influence of Different Therapies on EGFR Mutants by Circulating Cell-free DNA of Lung Adenocarcinoma and Prognosis]

背景与目的

表皮生长因子受体（epidermal growth factor receptor, EGFR）基因突变与肺腺癌患者TKI靶向治疗疗效和预后密切相关，常规组织分析其突变状态有诸多局限。本研究旨在探讨非小细胞肺癌（non-small cell lung cancer, NSCLC）患者血液循环游离DNA（cell-free DNA, cfDNA）检测EGFR基因突变在治疗前、传统化疗以及靶向治疗后的表达差异。分析血液cfDNA是否能准确检测EGFR基因突变并监测耐药基因T790M的变化，以及TKI在靶向治疗患者中的预后价值。

方法

应用ARMS（amplification refractory mutation system）法检测107例（50例治疗前、29例传统化疗和28例靶向治疗）肺癌患者配对血液和肿瘤组织样本的EGFR基因突变并比较其表达差异；计算检测的一致性、敏感性和特异性；分析血检对靶向治疗患者的预后价值。

结果

血浆cfDNA检测EGFR总突变率在107例肺癌患者中为56%（60例），而配对肿瘤组织样本检出率为77.6%（83例）。一一配对比较发现两者总体一致率为68.2%。血检的敏感性是72.3%，特异性为100%。依据治疗状态分组后发现治疗前组患者血液和肿瘤组织样本的检测一致率最高（74%, 37/50），而靶向组一致率最低（57.1%, 16/28），提示靶向治疗改变血浆cfDNA中EGFR基因状态。具体分析靶向组不一致病例发现50%新检出含T790M的双突变，提示靶向治疗后耐药基因出现。生存分析证实血检含T790M双突变组的无进展生存期（progression-free survival, PFS）和总生存期（overall survival, OS）均显著低于无T790M突变组。

结论

应用ARMS法检测血液循环游离DNA（circulating cell-free DNA, cfDNA）的EGFR基因突变是一种特异性高、敏感性好的检测方法。适用于治疗前晚期肺癌患者的EGFR基因突变状态检测。同时，适用于靶向治疗后监测T790M耐药突变状态及预测患者预后。

Detection of epidermal growth factor receptor mutations in lung adenocarcinoma cytological specimens by immunocytochemistry

Tyrosine kinase inhibitors of epidermal growth factor receptor (EGFR) improve the survival of patients with lung adenocarcinoma, and determine the EGFR mutation status before treatment is necessary. In contrast to biopsy samples, cytological specimens are obtained less invasively and are useful for EGFR mutation analyses. Recently, novel antibodies against two major EGFR mutations were developed: SP111, which is specific for the E746-A750 deletion in exon 19; and SP125, which is specific for the L858R mutation. To the best of our knowledge, no study has evaluated cytological specimens using the two novel antibodies, thus their specificity and sensitivity were examined in surgical resection, and cytological lung adenocarcinoma samples in the present study. Previous screening for EGFR mutation status by molecular testing identified delE746-A750 in 3 cases and the L858R mutation in 7 cases; the other cases did not have the L858R or the delE746-A750 mutation. Using a four-grade scoring system (score 0 to 3+), the immunohistochemistry (IHC) and immunocytochemistry (ICC) results were compared with those of molecular testing. Using a score of ≥2 as positive, IHC and ICC using SP111 demonstrated sensitivities of 100 and 33.3%, and specificities of 100 and 100%, respectively. IHC and ICC using SP125 revealed sensitivities of 100 and 71.4%, and specificities of 100 and 100%, respectively. Therefore, screening for EGFR mutations by ICC may facilitate therapeutic decision-making, particularly in medical centers that are unable to perform molecular testing.

Malignant pleural effusion: from bench to bedside

Malignant pleural effusion (MPE) is a common but serious condition that is related with poor quality of life, morbidity and mortality. Its incidence and associated healthcare costs are rising and its management remains palliative, with median survival ranging from 3 to 12 months. During the last decade there has been significant progress in unravelling the pathophysiology of MPE, as well as its diagnostics, imaging, and management. Nowadays, formerly bed-ridden patients are genotyped, phenotyped, and treated on an ambulatory basis. This article attempts to provide a comprehensive overview of current advances in MPE from bench to bedside. In addition, it highlights unanswered questions in current clinical practice and suggests future directions for basic and clinical research in the field.

Immunohistochemistry for EGFR Mutation Detection in Non-Small-Cell Lung Cancer

INTRODUCTION

The sensitivity and specificity of immunohistochemistry (IHC) was compared with the standard polymerase chain reaction (PCR)-based method for detecting common activating epidermal growth factor receptor (EGFR) mutations in non-small-cell lung cancer (NSCLC). Additionally, we evaluated predictive value of IHC EGFR mutation-positive status for EGFR tyrosine kinase inhibitor (TKI) treatment outcome and estimated cost-effectiveness for the upfront IHC testing.

METHODS

The trial included 79 consecutive EGFR mutation-positive and 29 EGFR mutation-negative NSCLC cases diagnosed with reflex PCR-based testing. Two mutation-specific antibodies against the most common exon 19 deletion, namely E746-A750del (clone SP111) and L858R mutation (clone SP125) were tested by using automated immunostainer. Sixty of 79 EGFR mutation-positive cases were treated with EGFR TKIs for advanced disease and included in treatment outcome analysis. A decision tree was used for the cost-effectiveness analysis.

RESULTS

The overall sensitivity and specificity of the IHC-based method compared with the PCR-based method were 84.8% (95% confidence interval [CI] 74.6-91.6) and 100% (95% CI 85.4-100), respectively. The median progression-free survival (PFS) and overall survival (OS) of patients with IHC-positive EGFR mutation status were highly comparable to the total cohort (PFS: 14.3 vs. 14.0 months; OS: 34.4 vs. 34.4 months). The PCR and IHC cost ratio needs to be approximately 8-to-1 and 4-to-1 in White and Asian populations, respectively, to economically justify upfront use of IHC.

CONCLUSION

The trial confirmed an excellent specificity with fairly good sensitivity of IHC with mutation-specific antibodies for common EGFR mutations and the accuracy of IHC testing for predicting response to EGFR TKIs. The use of upfront IHC depends mainly on the population EGFR mutation positivity probability.

MassARRAY, pyrosequencing, and PNA clamping for EGFR mutation detection in lung cancer tissue and cytological samples: a multicenter study

BACKGROUND

Testing for epidermal growth factor receptor (EGFR) mutation is an important process in the therapeutic plan of patients with lung cancer. Recently, MassARRAY, based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, has been shown to be a useful method for somatic mutation analysis with pyrosequencing and peptide nucleic acid clamping (PNAc).

METHODS

A total of 107 tissues and 67 cytological samples, which were confirmed to have lung adenocarcinoma at nine hospitals in Korea, were collected. Among the MassARRAY, pyrosequencing, and PNAc, the concordance rates and sensitivity of EGFR mutation detection were analyzed and validated in comparative tissue and cytological specimens.

RESULTS

The concordance rate between pyrosequencing and PNAc was higher than that between MassARRAY and either of the pyrosequencing and PNAc in both tissue and cytological samples. In a comparison of diagnostic performance, MassARRAY (sensitivity: 85.7 %) was higher than pyrosequencing (74.3 %) and PNAc (70 %) in tissue, although pyrosequencing (80.5 %) was more highly sensitive, compared to MassARRAY (70.7 %) and PNAc (70.7 %) in terms of cytology. Unexpectedly, use of MassARRAY resulted in a significantly different EGFR mutation detection rate between tissue and cytological samples.

CONCLUSIONS

When used for the detection of EGFR mutations, MassARRAY was more sensitive than pyrosequencing or PNA clamping in tissue, but not in cytological samples. In EGFR mutation detection between tissues and cytology, PNAc showed relatively higher concordance than MassARRAY or pyrosequencing.

Diamond: immunohistochemistry versus sequencing in EGFR analysis of lung adenocarcinomas

AIMS

Identification of epidermal growth factor receptor (EGFR) mutations in lung adenocarcinomas is the single most important predictor of clinical response and outcome using EGFR tyrosine kinase inhibitors (TKIs). EGFR E746-A750del and L858R mutations are the most common gene alterations, also predicting the best clinical response to TKIs. We evaluated the accuracy of EGFR mutation-specific antibodies in a large cohort of lung adenocarcinomas, with different molecular settings and types of tissue samples.

METHODS

300 lung adenocarcinomas diagnosed on cytology (48 cell blocks), biopsy (157 cases) and surgical resections (95 cases) were selected. All cases were investigated for EGFR by sequencing and two mutation-specific antibodies (clone 6B6 for E746-A750del; clone 43B2 for L858R) were tested using an automated immunostainer. Discordant results were investigated by next-generation sequencing (NGS).

RESULTS

Overall sensitivity and specificity of mutant-specific antibodies were 58.6% and 98.0%, respectively, and they increased up to 84% and 100% if only tumours harbouring E746-A750del were considered. In 13 discordant cases, NGS confirmed immunohistochemistry results in eight samples.

CONCLUSIONS

The EGFR mutation-specific antibodies have a fair/good sensitivity and good/high specificity in identifying classic mutations, but they cannot replace molecular tests. The antibodies work equally well on biopsies and cell blocks, possibly permitting a rapid screening in cases with poor material.

[Value of Cell Block in the Diagnosis of Malignant Pleural Effusion]

背景与目的  恶性胸腔积液(malignant pleural effusion, MPE)是由原发于胸膜的恶性肿瘤或者是转移至胸膜的恶性肿瘤造成的胸腔积液。对于不明原因的单侧胸腔积液, 首要任务是排除或者是确诊恶性胸腔积液。胸腔积液沉淀物是将送检胸腔积液细胞学剩余的胸腔积液进行离心或者是自然静置所获得的细胞块。此技术具有操作简单、有创性小、重复性高、对恶性胸腔积液的诊断率相对较高等特点, 在恶性胸腔积液的诊断、治疗等方面起着重要的作用。本文主要从沉淀物的制作方法、免疫组织化学染色检查的鉴别诊断价值、沉淀物的诊断优势及沉淀物行基因检测的临床应用价值等方面来论述胸腔积液沉淀物对恶性胸腔积液的诊断价值。

Pre-analytical issues in effusion cytology

Effusions or body cavity fluids are amongst the most commonly submitted samples to the cytology laboratory. Knowledge of proper collection, storage, preservation and processing techniques is essential to ensure proper handling and successful analysis of the sample. This article describes how the effusions should be collected and proper conditions for submission. The different processing techniques to extract the cellular material and prepare slides satisfactory for microscopic evaluation are described such as direct smears, cytospins, liquid based preparations and cell blocks. The article further elaborates on handling the specimens for additional ancillary testing such as immunostaining and molecular tests, including predictive ones, as well as future research approaches.

Comparison of EGFR mutation detection between the tissue and cytology using direct sequencing, pyrosequencing and peptide nucleic acid clamping in lung adenocarcinoma: Korean multicentre study

BACKGROUND

The importance of sensitive methods for the detection of epidermal growth factor receptor (EGFR) mutation is emphasized. The aim of this study is to perform comparative and concordance analyses of direct sequencing, pyrosequencing and peptide nucleic acid (PNA) clamping for detecting EGFR gene mutations using archived tissue and cytology specimens.

METHODS

Samples from a total of 112 cases, which were diagnosed with adenocarcinoma of the lung at nine hospitals in Korea were collected. Using the above three methods, the concordance rates of EGFR mutations in exons 18, 19, 20 and 21 were analysed and validated in comparative tissue and cytology specimens.

RESULTS

Comparison of EGFR mutation detection between the tissue and cytology had a high concordance rate. The diagnostic performance of pyrosequencing and PNA clamping in tissue was higher than that of direct sequencing as well as cytology. Additionally, among some of the patients who had EGFR wild type by single method, EGFR mutations were detected by other methods. Cytology specimens had a diagnostic performance for the detection of EGFR mutations.

CONCLUSIONS

Cytology specimens had a diagnostic performance for the detection of EGFR mutations that was comparable to that of tissues. For detecting EGFR mutations, pyrosequencing or PNA clamping was more sensitive than direct sequencing. In EGFR mutation negative patients who are difficult to obtain tissue, repeating test using pyrosequencing or PNA clamping is recommended to improve the detection rate of EGFR mutation than only one, especially in cytology.

Mutation status concordance between primary lesions and metastatic sites of advanced non-small-cell lung cancer and the impact of mutation testing methodologies: a literature review

Increased understanding of the genetic aetiology of advanced non-small-cell lung cancer (aNSCLC) has facilitated personalised therapies that target specific molecular aberrations associated with the disease. Biopsy samples for mutation testing may be taken from primary or metastatic sites, depending on which sample is most accessible, and upon differing diagnostic practices between territories. However, the mutation status concordance between primary tumours and corresponding metastases is the subject of debate. This review aims to ascertain whether molecular diagnostic testing of either the primary or metastatic tumours is equally suitable to determine patient eligibility for targeted therapies. A literature search was performed to identify articles reporting studies of mutations in matched primary and metastatic aNSCLC tumour samples. Clinical results of mutation status concordance between matched primary and metastatic tumour samples from patients with aNSCLC were collated. Articles included in this review (N =26) all reported mutation status data from matched primary and metastatic tumour samples obtained from adult patients with aNSCLC. Generally, substantial concordance was observed between primary and metastatic tumours in terms of EGFR, KRAS, BRAF, p16 and p53 mutations. However, some level of discordance was seen in most studies; mutation testing methodologies appeared to play a key role in this, along with underlying tumour heterogeneity. Substantial concordance in mutation status observed between primary and metastatic tumour sites suggests that diagnostic testing of either tumour type may be suitable to determine a patient's eligibility for personalised therapies. As with all diagnostic testing, highly sensitive and appropriately validated mutation analysis methodologies are desirable to ensure accuracy. Additional work is also required to define how much discordance is clinically significant given natural tumour heterogeneity. The ability of both primary and metastatic tumour sites to accurately reflect the tumour mutation status will allow more patients to receive therapies personalised to their disease.

Lung cancer coexisting with ipsilateral pleural effusion

SUMMARY 

Invasion beyond the elastic layer of the visceral pleura and/or diffuse pleural metastatic spread affects negatively survival in lung cancer. Presence of pleural effusion is also associated with poor prognosis, and image techniques can be of great help for diagnosis. When pleural fluid cytology is negative, thoracoscopy is advisable before attempting tumor resection, in order to detect unsuspected pleural metastases. If widespread pleural malignancy is confirmed, chemical pleurodesis using graded talc (with particles larger than 20 µm in diameter) is the best option, unless the lung is unable to re-expand. In this case, or when a previous pleurodesis has failed, or there is a short life expectancy, placement of a indwelling pleural catheter is the treatment of choice.

EGFR analysis: current evidence and future directions

Until a few years ago, only lung cancer histological specimens were considered suitable for testing epidermal growth factor receptor (EGFR) mutations. Then, several retrospective studies were designed to test EGFR mutation on a sizeable number of parallel cytological and histological samples obtained from the same patients and, even more recently, several institutions reported their prospective clinical experiences on routine specimens. Basing on these studies the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology have recently considered cytological samples suitable for EGFR testing. Therefore, it seems timely to draw together the threads of this large body of information in order that cytopathologists can be knowledgeable partners in the multidisciplinary process of targeted cancer therapy and to help refine current testing guidelines. This review addresses (1) the more common proposed techniques including the use of direct cytologic smears cell blocks and liquid based cytology; (2) the issues related to current practice, which in Europe is external centralized testing that is usually done on samples containing very few cells; and (3) the future directions based on the implementation on lung cytology of next generation sequencing approaches.

The role of molecular analyses in the diagnosis and treatment of non-small-cell lung carcinomas

Non-small-cell lung cancer (NSCLC) subtyping has recently been a key factor in determining patient management with novel drugs. In addition, the identification of distinct oncogenic driver mutations frequently associated with NSCLC histotype and coupled to the clinical responses to targeted therapies have revolutionized the impact of histologic type and molecular biomarkers in lung cancer. Several molecular alterations involving different genes (EGFR, KRAS, ALK, BRAF, and HER2) seem to have a remarkable predilection for adenocarcinoma and specific inhibitors of EGFR and ALK are now available for patients with adenocarcinoma harboring the relevant gene alterations. The efficacy of histology-based and molecular-targeted therapies had a deep impact in (1) re-defining classification of lung cancer (particularly adenocarcinomas) and (2) routine clinical practice of pathologists involved in optimization of handling of tissue samples in order to guarantee NSCLC subtyping with the help of immunohistochemistry and adequately preserve tumor cells for molecular analysis. In agreement with the modern multidisciplinary approach to lung cancer, we reviewed here the diagnostic and predictive value of molecular biomarkers according to the clinical, pathologic, and molecular biologist viewpoints.

The diagnostic accuracy of pleural effusion and plasma samples versus tumour tissue for detection of EGFR mutation in patients with advanced non-small cell lung cancer: comparison of methodologies

Aims

To evaluate the suitability of malignant pleural effusion (MPE) and plasma as surrogate samples for epidermal growth factor receptor (EGFR) mutation detection, and compare three different detection methods.

Methods

Matched tissue and plasma samples were collected from patients with advanced non-small cell lung cancer (NSCLC) (stage IIIB/IV adenocarcinoma/adenosquamous carcinoma), with matched MPE samples collected from a subgroup. DNA was extracted from tissue, MPE cell block, MPE supernatant and plasma before mutation detection by amplification refractory mutation system (ARMS) (all samples), Sanger sequencing and mutant-specific immunohistochemistry (IHC) (tissue and MPE cell blocks only).

Results

Sensitivity of MPE cell block, MPE supernatant and plasma versus tissue: 81.8% (9/11), 63.6% (7/11) and 67.5% (27/40); specificity was 80.0% (8/10), 100% (10/10) and 100% (46/46), respectively. Sensitivity of Sanger sequencing versus ARMS: 81.8% (27/33) for tissue, 40% (4/10) for MPE cell blocks; specificity was 100% (36/36 and 12/12) for both. Sensitivity of mutant-specific IHC versus ARMS: 54.8% (17/31) for tissue, 50.0% (6/12) for MPE cell blocks; specificity was 97.1% (34/35) and 100% (14/14), respectively.

Conclusions

MPE and plasma are valid surrogates for NSCLC tumour EGFR mutation detection when tissue is not available. ARMS is most suitable for mutation detection in tissue and MPE cell blocks; however, mutant-specific IHC could be a complementary method when DNA-based molecular testing is unavailable.

Pleurodesis with povidone-iodine, as an effective procedure in management of patients with malignant pleural effusion

OBJECTIVE

Overtime, malignant pleural effusion (MPE) arises in advanced-stages of malignancies and frequently heralds a poor prognosis. If the underlying malignancy is chemo sensitive, systemic chemotherapy may control pleural effusion. A common method for the management of the patients with refractory MPE is pleurodesis through the introduction of sclerosing agents such as talc, bleomycin administered/instilled into the pleural cavity. However, the present prospective study aimed to investigate the efficacy and safety of pleurodesis with povidone-iodine (Betadine) in patients with MPE admitted in Sari General Hospital during 2008-2011.

METHODS

Thirty-six patients who underwent pleurodesis by instilling povidone-iodine through a thoracostomy tube, as a bedside procedure were enrolled in the study. For evaluating the effect of povidone-iodine on thyroid gland, the authors measured the thyroid function tests before and after the pleurodesis at 1 week.

RESULTS

The response to this procedure was complete in 26 patients (72.2%) and partial in 7 patients (19.4%). Treatment failure was displayed in 3 patients (8.3%). The overall success rate was 91.6%. In post-procedure, the most common complaints of the patients were pain (35.9%) followed by dyspnea, burning and fever. Povidone-iodine does not affect on thyroid function tests.

CONCLUSIONS

Povidone-iodine is an effective, inexpensive, safe and feasible agent for chemical pleurodesis in management of MPE.

Current and future options for the diagnosis of malignant pleural effusion

INTRODUCTION

Malignant pleural effusion (MPE) is a frequent problem faced by clinicians, but tumor pleural involvement can be seen without effusion.

AREAS COVERED

Imaging, pleural fluid analysis, biomarkers for MPE, needle pleural biopsy and thoracoscopy. To prepare this review, we performed a search using keywords: 'diagnosis' + 'malignant' + 'pleural' + 'effusion' (all fields) in PubMed, and found 4106 articles overall (until 16 January 2013, 881 in the last 5 years).

EXPERT OPINION

Ultrasound techniques will stay as valuable tools for pleural effusions. Biomarkers in pleural fluid do not currently provide an acceptable yield for MPE. In subjects with past history of asbestos exposure, some serum or plasma markers (soluble mesothelin, fibulin) might help in selecting cases for close follow-up, to detect mesothelioma early. Needle pleural biopsy is justified only if used with image-techniques (ultrasound or CT) guidance, and thoracoscopy is better for both diagnosis and immediate palliative treatment (pleurodesis). Animal models of MPE and 'spheroids' are promising for research involving both pathophysiology and therapy. Considering the possibility of direct pleural delivery of nanotechnology-developed compounds-fit to both diagnosis and therapy purposes ('theranostics')-MPE and mesothelioma in particular are likely to benefit sooner than later from this exciting perspective.

EGFR mutation testing in lung cancer: a review of available methods and their use for analysis of tumour tissue and cytology samples

Aims

Activating mutations in the gene encoding epidermal growth factor receptor (EGFR) can confer sensitivity to EGFR tyrosine kinase inhibitors such as gefitinib in patients with advanced non-small-cell lung cancer. Testing for mutations in EGFR is therefore an important step in the treatment-decision pathway. We reviewed reported methods for EGFR mutation testing in patients with lung cancer, initially focusing on studies involving standard tumour tissue samples. We also evaluated data on the use of cytology samples in order to determine their suitability for EGFR mutation analysis.

Methods

We searched the MEDLINE database for studies reporting on EGFR mutation testing methods in patients with lung cancer.

Results

Various methods have been investigated as potential alternatives to the historical standard for EGFR mutation testing, direct DNA sequencing. Many of these are targeted methods that specifically detect the most common EGFR mutations. The development of targeted mutation testing methods and commercially available test kits has enabled sensitive, rapid and robust analysis of clinical samples. The use of screening methods, subsequent to sample micro dissection, has also ensured that identification of more rare, uncommon mutations is now feasible. Cytology samples including fine needle aspirate and pleural effusion can be used successfully to determine EGFR mutation status provided that sensitive testing methods are employed.

Conclusions

Several different testing methods offer a more sensitive alternative to direct sequencing for the detection of common EGFR mutations. Evidence published to date suggests cytology samples are viable alternatives for mutation testing when tumour tissue samples are not available.