Comparison of the expression levels of napsin A, thyroid transcription factor-1, and p63 in nonsmall cell lung cancer using cytocentrifuged bronchial brushings

Advances in diagnostic liquid-based cytology

Liquid-based cytology (LBC) has changed the landscape of gynaecological cytology. A growing demand exists for LBC in diagnostic cytology, particularly for ancillary testing, such as immunocytochemistry and molecular testing. Ancillary testing solely based on conventional preparation (CP) methods remains challenging. Recently, the increased demand for specialist testing and minimally invasive techniques, such as endoscopic ultrasonography fine-needle aspiration, to obtain cellular samples has led to an increasing demand for ancillary testing on cytology LBC supernatant, slides and cell block (CB). This facilitates the diagnosis and prognosis in cytology samples enabling personalized treatment. An understanding of the history and future prospects of LBC is crucial for its application in routine diagnostics by cytopathologists and cytotechnologists. In this review, we initiated an internet search using the keyword 'liquid-based cytology', and we conducted a literature review to discuss the usefulness of combined diagnosis of LBC and CP, immunocytochemistry and molecular testing and assessed the quality of nucleic acids in diagnostic LBC. High-quality and cell-rich diagnostic LBC surpassed the CP method alone in terms of reliability and versatility of ancillary testing in cytological diagnosis. Conclusively, diagnostic LBC lends itself to various new technologies and is expected to continue evolving with innovations in the future.

Immunoexpression of TTF1 and p63 Differentiates Lung Adenocarcinomas in Sputum Samples

Context

Differentiating NSCLC as either adeno or squamous type and identification of Epidermal Growth Factor Receptor (EGFR) mutations is clinically relevant for lung cancer patients for selecting treatment. Thyroid transcription factor-1 (TTF-1) and p63 were demonstrated as useful markers for histologic typing of lung cancer. Mutation and overexpression of EGFR has been reported in a subset of non-small cell lung cancers. If these markers can be validated for the differential diagnosis of adenocarcinoma in a sputum sample itself, it will be highly beneficial for lung cancer patients.

Aims

To evaluate whether immunocytochemical expression of TTF-1, p63, and EGFR proteins in sputum samples can be used for differential diagnosis of lung adenocarcinoma by comparing with that of the corresponding tissue samples.

Settings and Design

Ninety sputum samples and matched tissue samples were used for the study.

Subjects and Methods

Monolayered smears and cell blocks of sputum and the corresponding tissue samples were immunostained with the standard ABC method. The expression patterns of these markers were analyzed statistically and compared with clinic-pathological parameters.

Statistical Analysis Used

Chi-square test and paired t-test.

Results

The p63 protein had a positive expression in 73.9% of SCC whereas TTF1 had positive expression in 75.8% of ADC. The EGFR expression was positive in 27 cases of adenocarcinoma, 21 cases of SCC and 19 cases of NSCLC.

Conclusions

Immunocytochemistry of the aforementioned antibodies in sputum samples can be used as supplementary evidence for the subtyping of NSCLC.

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.

Insulinoma-associated protein 1 expression in pancreatic neuroendocrine tumours in endoscopic ultrasound-guided fine-needle aspiration cytology: An analysis of 14 patients

BACKGROUND

Insulinoma-associated protein 1 (INSM1) has been reported to be a useful marker for diagnosing pancreatic neuroendocrine tumours (PNETs). However, INSM1 expression in endoscopic ultrasound-guided fine needle aspiration cytology has not been examined. We evaluated INSM1 expression in the cytology of cases diagnosed with PNETs.

METHODS

We immunocytochemically stained INSM1 and Ki-67 in 14 PNET cases, and according to the 2017 World Health Organisation criteria, seven PNET Grade 1 cases, four Grade 2 cases and three Grade 3/neuroendocrine carcinoma cases were identified. As a control for INSM1 and Ki-67 expression, we used cytological specimens from 15 cases of pancreatic ductal adenocarcinoma.

RESULTS

In PNET cases, INSM1-expressing tumour cells were identified in all cytological specimens of PNET. The median INSM1 expression rate in Grade 1 cases was 49.8% (mean ± standard deviation: 55.1 ± 12.5%, min: 39.3%, max: 74.1%), and in Grade 2 and Grade 3/neuroendocrine carcinoma cases was 81.1% (mean ± standard deviation: 77.6 ± 18.6%, min: 50.3%, max: 100%). However, there was no correlation between INSM1 and Ki-67 expression (r = -0.15). The median expression rate in PNET cases was 64.3%, which was significantly higher than that in pancreatic ductal adenocarcinoma cases (P < 0.0001).

CONCLUSION

INSM1 immunocytochemistry of cytological specimens obtained from endoscopic ultrasound-guided fine needle aspiration cytology can accurately diagnose PNETs; therefore, INSM1 could be an important diagnostic tool in assessing therapeutic strategies, including molecular-targeted therapy.

SurePath® LBC improves the diagnostic accuracy of intrahepatic and hilar cholangiocarcinoma

INTRODUCTION

The current study aimed to compare cytology using SurePath^® (SP)-LBC and biliary tissue histology (BTH) for the diagnosis of biliary disease.

METHODS

Between January 2014 and December 2016, 57 patients underwent endoscopic retrograde cholangiopancreatography for the diagnosis of biliary disease. Biliary cytological samples were processed using SP-LBC and subsequently BTH was performed. A final diagnosis was confirmed by surgery (23 malignant cases) and clinical follow-up (34 benign and malignant cases): 18 extrahepatic cholangiocarcinoma; 17 intrahepatic/hilar cholangiocarcinoma (intra/H-CC); eight other malignant disease; and 14 benign biliary disease. The diagnoses made using SP-LBC and BTH were classified into four categories: (1) benign; (2) indeterminate; (3) suspicious for malignancy/malignant; and (4) inadequate. In addition, diagnostic accuracy was compared between SP-LBC and BTH.

RESULTS

Although 23% (13/57) of BTH samples were classified as inadequate, all SP-LBC cases were classified as adequate. Among 43 malignant cases, 11 normal, four indeterminate and 28 suspicious for malignancy/malignant were found using SP-LBC (26%, 9% and 65%, respectively), in contrast to 10 inadequate, nine normal, 10 indeterminate and 14 suspicious for malignancy/malignant observed using BTH (23%, 21%, 23%, and 33%, respectively). The identification of malignant cells was strikingly different between SP-LBC and BTH. Furthermore, limited to intra/H-CC, accuracy was significantly higher using SP-LBC than using BTH (P < .001).

CONCLUSIONS

SP-LBC of the biliary tract is a useful and reliable method for diagnosing biliary malignant disease and has an advantage over BTH for detecting malignant cells and accurately diagnosing intra/H-CC.

Laparoscopic adrenalectomy for solitary adrenal metastasis from lung cancer

BACKGROUND AND OBJECTIVES

Several studies have been reported on the problem of determining when laparoscopic adrenalectomy is indicated for solitary adrenal metastasis of malignant tumors. Our efforts at answering this question constitute the basis of this report.

METHODS

From June 2010 to June 2011, laparoscopic adrenalectomy was performed in 10 lung cancer patients with solitary adrenal metastases (5 adenocarcinomas, 1 squamous cell carcinoma, 1 large cell carcinoma, 1 small cell carcinoma, and 2 pleomorphic carcinomas). The surgical results of all 10 patients were examined.

RESULTS

Adrenal swelling was detected by computed tomography in all patients except 1 case of pleomorphic carcinoma. The findings of positron emission tomography-computed tomography were positive in 8 patients, including the 2 cases with pleomorphic carcinomas. Laparoscopic surgery was successfully performed in 9 cases. In the eighth patient (a case of pleomorphic carcinoma with adrenal swelling), laparoscopic adrenalectomy was attempted but conversion to open surgery was required because of clear evidence of pancreatic invasion.

CONCLUSION

The results obtained in this study, along with other published reports, support 4 criteria as operative indications for laparoscopic adrenalectomy in solitary adrenal metastasis from the lung: (1) the primary lung cancer is resected or can be cured by radical chemotherapy, (2) metastasis is limited to the adrenal gland only, (3) adrenal metastasis does not invade the surrounding organs, and (4) the size of the adrenal tumor does not exceed 10 cm. In cases of pleomorphic carcinoma, laparoscopic adrenalectomy should be performed when positron emission tomography-computed tomography results are positive.

Epidermal growth factor receptor mutation status in cell-free DNA supernatant of bronchial washings and brushings

BACKGROUND

The aim of the current study was to examine whether it would be possible to detect epidermal growth factor receptor (EGFR) mutations in cytology cell-free DNA (ccfDNA) from the supernatant fluids of bronchial cytology samples.

METHODS

This study investigated cell damage via immunostaining with a cleaved caspase 3 antibody and the quantity of cell-free DNA in supernatant fluid from 2 cancer cell lines, and the EGFR mutation status was evaluated via polymerase chain reaction (PCR) analysis. EGFR mutations were also evaluated via PCR analysis in 74 clinical samples of ccfDNA from bronchial washing samples with physiological saline or from bronchial brushing liquid-based cytology samples with CytoRich Red.

RESULTS

The quantity and fragmentation of cell-free DNA in the supernatant fluid and the cell damage and cleaved caspase 3 expression in the sediment gradually increased in a time-dependent manner in the cell lines. In the 74 clinical samples, the quantity of ccfDNA extracted from the supernatant was adequate to perform the PCR assay, whereas the quality of ccfDNA in physiological saline was often decreased. The detection of EGFR mutations with ccfDNA showed a sensitivity of 88.0%, a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 89.7%, and an accuracy of 94.1% in samples with malignant or atypical cells.

CONCLUSIONS

These results suggest that activating EGFR mutations can be detected with ccfDNA extracted from the supernatant fluid of liquid-based samples via a PCR assay. This could be a rapid and sensitive method for achieving a parallel diagnosis by both morphology and DNA analysis in non-small cell lung cancer patients.

Immunostaining for thyroid transcription factor 1, Napsin A, p40, and cytokeratin 5 aids in differential diagnosis of non-small cell lung carcinoma

The present study aimed to examine the effectiveness of immunostaining of cytological specimens in discerning squamous from non-squamous cell carcinoma. Various combinations of six antibodies were examined in order to determine the optimal combination for use in differential diagnosis. Immunostaining was performed using tumor imprint smears obtained from 70 lung carcinoma cases. The results were scored based on positive area and intensity. For objective evaluation, scores for thyroid transcription factor 1 (TTF-1), napsin A, and CK CAM5.2 were expressed with positive values, while those for p40, cytokeratin (CK) 5/6 and CK5 were expressed with negative values. Histograms were produced to evaluate which combination was the most effective in differentiating squamous cell carcinoma from adenocarcinoma. The sensitivity for these molecules in adenocarcinoma was 88% for TTF-1, 85% for napsin A, and 100% for CAM5.2. In squamous cell carcinomas, sensitivity was determined to be 90% for p40, 86% for CK5, and 76% for CK5/6. The specificity for these molecules was calculated as 100%, 95%, 43%, 98%, 100% and 95%, respectively. Each combination was evaluated for scoring and the values were averaged. The most effective combination for mode and mean was TTF-1, napsin A, p40, and CK5, for which all adenocarcinomas had a score >1, and all squamous cell carcinomas scored <-2. Immunostaining scoring may therefore be useful for the differential diagnosis of these carcinomas when a limited number of tumor cells are present.

The high diagnostic accuracy of combined test of thyroid transcription factor 1 and Napsin A to distinguish between lung adenocarcinoma and squamous cell carcinoma: a meta-analysis

Background

Accurate classification of non-small cell lung cancer (NSCLC) using morphological features has several limitations. However, the use of thyroid transcription factor 1 (TTF-1) and Napsin A as markers for the identification of various subtypes of NSCLC has shown promise. This meta-analysis was designed to evaluate the diagnostic value of combined TTF-1 and Napsin A test to distinguish lung adenocarcinoma from squamous cell carcinoma.

Methods

The Medline, EMBASE and Web of Science databases were searched, along with the reference lists of relevant articles (up to May 4, 2014). Ten studies containing 1,446 subjects were identified. The sensitivity, specificity, diagnostic odds ratio (DOR) and area under the summary receiver operating characteristics curve (AUC) were calculated to estimate the combined diagnostic value of TTF-1 and Napsin A.

Results

The pooled sensitivity and specificity were 0.76 (95% CI: 0.69–0.83) and 1.00 (95% CI: 0.92–1.00), respectively. The positive and negative likelihood ratios were 877.60 (95% CI: 8.40–91533.40) and 0.24 (95% CI: 0.18–0.32). The DOR was 3719 (95% CI: 33–414884). The AUC was 0.92 (95%CI: 0.89–0.94). The patient's location was a source of heterogeneity for sensitivity. The patient's location, the study's sample size and the threshold used to determine positive staining were consistently found to be sources of heterogeneity for specificity in subgroup analyses and meta-regression.

Conclusions

The combined test of TTF-1 and Napsin A presents a promising alternative method, useful to distinguish between lung adenocarcinoma and squamous cell carcinoma.

Fixation effect of SurePath preservative fluids using epidermal growth factor receptor mutation-specific antibodies for immunocytochemistry

BACKGROUND

Cytological diagnosis of respiratory disease has become important, not only for histological typing using immunocytochemistry (ICC) but also for molecular DNA analysis of cytological material. The aim of this study was to investigate the fixation effect of SurePath preservative fluids.

METHODS

Human lung cancer PC9 and 11-18 cell lines, and lung adenocarcinoma cells in pleural effusion, were fixed in CytoRich Blue, CytoRich Red, 15% neutral-buffered formalin, and 95% ethanol, respectively. PC9 and 11-18 cell lines were examined by ICC with epidermal growth factor receptor (EGFR) mutation-specific antibodies, the EGFR mutation DNA assay, and fluorescence in situ hybridization. The effect of antigenic storage time was investigated in lung adenocarcinoma cells in pleural effusion by ICC using the lung cancer detection markers.

RESULTS

PC9 and 11-18 cell lines in formalin-based fixatives showed strong staining of EGFR mutation-specific antibodies and lung cancer detection markers by ICC as compared with ethanol-based fixatives. DNA preservation with CytoRich Blue and CytoRich Red was superior to that achieved with 95% ethanol and 15% neutral-buffered formalin fixatives, whereas EGFR mutations by DNA assay and EGFR gene amplification by fluorescence in situ hybridization were successfully identified in all fixative samples. Although cytoplasmic antigens maintained high expression levels, expression levels in nuclear antigens fell as storage time increased.

CONCLUSIONS

These results indicate that CytoRich Red is not only suitable for ICC with EGFR mutation-specific antibodies, but also for DNA analysis of cytological material, and is useful in molecular testing of lung cancer, for which various types of analyses will be needed in future.

Immunohistochemical profiling of ALK fusion gene-positive adenocarcinomas of the lung

Our aim was to determine whether or not non-small-cell lung cancer is squamous cell carcinoma (SQCC); even in small samples, it is essential in view of the side effects attendant on new therapeutics. Lung adenocarcinoma (ADC) with the EML4-ALK fusion gene has been described as demonstrating mucinous cribriform/acinar growth and signet-ring cells, sometimes partially simulating SQCC. We investigated the relation among morphology, anaplastic lymphoma kinase (ALK) rearrangement, and immunophenotype in 321 ADCs by tissue microarray using SQCC markers cytokeratin (CK)5/6, CK14, desmocollin-3, desmoglein-3, p40, p63 versus ADC markers thyroid transcription factor (TTF)-1 and napsin A. Unlike 312 ALK-negative ADCs, 9 ALK-positive cases were negative for 4 SQCC markers. Only 1 ALK-positive ADC showing assertive morphology was positive for CK5/6 and p63 as well as for TTF-1 and napsin A. Coexpression of TTF-1/p40 was not observed, unlike that of TTF-1/p63 reported previously. There was no statistically significant difference between ALK-negative and ALK-positive ADC by immunohistochemical profiling.

Napsin A is an independent prognostic factor in surgically resected adenocarcinoma of the lung

INTRODUCTION

Napsin A is regarded as a marker of lung adenocarcinoma. However, no comprehensive analyses of napsin A-positive lung ADCs or the prognostic significance of napsin A expression have been reported to date.

METHODS

110 primary lung adenocarcinoma cases were analyzed for clinicopathologic parameters, including overall survival, stage, histology, napsin A and TTF-1 expression, EGFR mutation, and ALK rearrangement.

RESULTS

Napsin A-positive adenocarcinomas were significantly more prevalent among tumors characterized as relatively small (p = 0.023), non-solid predominant (p < 0.001), non-mucinous/enteric (p < 0.001), positive for TTF-1 expression (p < 0.001), and positive for EGFR mutation (p = 0.001). Multivariate analysis of overall survival demonstrated that the absence of napsin A was an independent prognostic factor for reduced survival time (p = 0.002).

CONCLUSION

Clinicopathologic characteristics associated with napsin A-positive lung ADC are similar to and overlap with those of TTF-1-positive ADCs. The absence of napsin A is an independent poor prognostic factor in surgically resected adenocarcinoma. Further studies are necessary to determine the role of napsin A in the progression of lung adenocarcinoma.