KRAS Mutation Analysis Using Cell-free DNA of Pancreatic Cancer.

BACKGROUND/AIM: Detection of pancreatic cancer using small samples of the pancreas obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) remains a challenge. The purpose of this study was to investigate whether the detection of KRAS mutations in cell-free DNA (cfDNA) extracted from supernatants of liquid-based fixed cytology (LBC) specimens obtained using EUS-FNA in solid pancreatic cancer can be an auxiliary test for differential diagnosis. The purpose of this study was to investigate whether the detection of KRAS mutations in cell-free DNA (cfDNA) extracted from supernatants of liquid-based fixed cytology (LBC) specimens obtained using EUS-FNA in solid pancreatic cancer can be an auxiliary test for differential diagnosis. PATIENTS AND METHODS: This was a single-institution cohort study that included 50 patients with pancreatic lesions. cfDNA was isolated from the supernatant of fixed LBC samples, and KRAS mutation status was compared between cfDNA samples and FFPE small fragment tissues. RESULTS: Of the 50 cfDNA samples, 84% (42/50) were valid. KRAS mutations were detected in 57.1% (24/42) of the 42 valid samples. The sensitivity, specificity, and accuracy of KRAS mutation detection using cfDNA samples in the pancreatic lesions were 63.2% (24/38), 100.0% (4/4), and 66.7% (28/42), respectively. KRAS mutation status between FFPE small tissues and cfDNA samples were comparable. CONCLUSION: Gene mutation analysis using cfDNA from the supernatant of fixed LBC samples is an effective ancillary diagnostic tool for pancreatic cancer.

Significance of neoadjuvant chemoradiotherapy for borderline resectable pancreatic head cancer: Pathological local invasion and microvessel invasion analysis.

Borderline resectable pancreatic head cancer (BR-PHC) has low resectability due to vascular invasion. Although the clinical effects of neoadjuvant chemoradiotherapy (NAC-RT) for BR-PHC have been examined, few studies have reported its pathological aspects. The present study retrospectively investigated the effect of NAC-RT on the histological features of BR-PHC. A total of 29 patients with BR-PHC who underwent NAC-RT, and 55 controls with resectable PHC, who underwent pancreaticoduodenectomy at the Kurume University Hospital. Tumor staging, lymphovascular invasion (LVI), and microvessel invasion (MVI) were evaluated. The median tumor size in the NAC-RT group was 2.0 cm, and it was smaller than that of the control group (P=0.006). The rates of lymph node metastasis, LVI, and MVI were significantly lower in the NAC-RT group (P<0.001, 0.002, and 0.015, respectively). Overall survival in the NAC-RT group was comparable to that in the control group, although patients with BR-PHC generally had a poorer prognosis than those with resectable PHC. Patients in the NAC-RT group without portal vein invasion (PVI) had a significantly better prognosis than those with PVI in the control group (P=0.002). NAC-RT may be beneficial for patients with BR-PHC by inhibiting local invasion and metastasis as prognosis following resection could be equivalent to that of patients with conventional ductal adenocarcinoma.

Insulinoma-associated protein 1 is a novel diagnostic marker of small cell lung cancer in bronchial brushing and cell block cytology from pleural effusions: Validity and reliability with cutoff value.

BACKGROUND: In recent years, insulinoma-associated protein 1 (INSM1) has been shown to be a key regulator of neuroendocrine development, and it has been evaluated for diagnostic use in some organs. METHODS: To evaluate the relationship between INSM1 and synaptophysin, and to confirm the cutoff value using receiver operating characteristic curve (ROC) analysis, the authors performed INSM1 immunocytochemistry using cell block (CB) samples from 53 cases of bronchial brushings and 32 cases of pleural effusions (29 small cell lung cancer [SCLC] specimens and 56 non-small cell lung cancer specimens). The marker expression ratio was calculated by counting the positive tumor cells, and the tumor proportion score (TPS) was applied. RESULTS: INSM1 was expressed in all SCLC specimens, but generally was expressed in <10% of tumor cells in adenocarcinomas. In bronchial brushing samples of SCLC, the INSM1 TPS was 37.5% (staining of >50%), 25.0% (staining of 25%-50%), 29.5% (staining of 10%-25%), and 8.3% (staining of 1%-10%). There were 3 cases (12.5%) with no detectable synaptophysin expression, although the correlation between nuclear INSM1 expression and cytoplasmic synaptophysin expression was statistically significant (P < .001). Receiver operating characteristic curve analysis indicated that 8.68% was the best cutoff value for INSM1, and the sensitivity and specificity between SCLC and non-small cell lung cancer for expression of INSM1 were 95.8% and 100.0%, respectively, in bronchial brushing samples at that cutoff value. CONCLUSIONS: INSM1 is a novel diagnostic marker for SCLC, and is useful in both bronchial brushing and pleural effusion cytology specimens. Because INSM1 generally is expressed in <10% of tumor cells in adenocarcinomas, determining an accurate cutoff value for INSM1 is important in the diagnosis of SCLC.

Screening system for epidermal growth factor receptor mutation detection in cytology cell-free DNA of cerebrospinal fluid based on assured sample quality.

BACKGROUND: The cobas® epidermal growth factor receptor (EGFR) Mutation Test v2 designed for cell-free DNA (cfDNA) is approved as a companion diagnostic for osimertinib therapy. The aim of this study was to evaluate the concordance of EGFR mutation detection between paired primary or recurrent samples, and cerebrospinal fluid (CSF) cytology samples of lung cancer patients. METHODS: In total, 26 lung cancer patients with supernatant cytology cfDNA in CSF were analysed for EGFR mutations using the cobas® EGFR Mutation Test v2.0 designed for cfDNA, and the concordance rates between CSF cfDNA and primary or recurrent samples were investigated. RESULTS: Of the 26 CSF cytology cfDNA samples, 46.1% (12/26) were valid and 53.9% (14/26) were invalid. Sensitivity, specificity and accuracy between the valid CSF cfDNA samples and primary or recurrent samples for detection of EGFR mutation, including T790M were 87.5%, 100.0% and 91.7%, respectively. Amounts of both inflammatory cells and tumour cells in CSF cytology were higher in the valid evaluation samples than in the invalid samples (P < .05), and mutant EGFR was detected in 80.0% (4/5) of the valid CSF cytology cfDNA samples with a negative cytology diagnosis. CONCLUSIONS: The cobas® EGFR Mutation Test v2.0 can accurately detect EGFR mutations, including T790M, from supernatant cfDNA of CSF cytology samples. Utilisation of supernatant cytology cfDNA in CSF will allow us to perform both EGFR mutation analysis and cytopathological diagnosis at the same time. This represents a new role of cytology in patient treatment, based on assured sample quality.

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.

The expression of programed death ligand-1 could be related with unfavorable prognosis in salivary duct carcinoma.

BACKGROUND: Salivary duct carcinoma (SDC) is a rare tumor occurring in the salivary gland. SDC is a highly aggressive tumor and its prognosis is extremely poor. Effective treatments in advanced SDC have not yet been established. Recently, immune checkpoint inhibitors have paved the way for the treatment of various malignancies. We examined the expressions of programed death ligand (PD-L) 1/PD-L2 and programed death (PD-1), and the correlation of clinicopathological findings. METHODS: We examined 18 cases of SDC and conducted immunohistochemical staining using formalin-fixed paraffin-embedded full-face sections. RESULTS: The expression of PD-L1 and PD-L2 in tumor cells was observed in nine cases (50%) and 14 cases (78%), respectively. Cases with a high expression of PD-L1 and PD-L2 were found in four (22%) and seven cases (39%), respectively. The cases with a high expression of PD-L1 showed significantly shorter overall survival compared to those with low PD-L1 expression and null expression. We also examined the expression of PD-L1/PD-L2 and PD-1 of tumor-infiltrating mononuclear cells (TIMC) in stroma. The expressions of PD-L1 in tumor cells and stroma had a significant correlation. Association between the expressions of PD-L1 in tumor cells and those of PD-1 in stroma was significant. However, PD-L2 expression in the tumor had no significant correlation with expression in TIMCs. PD-L1, PD-L2 and PD-1 expressions in stroma were not associated with patient prognosis. CONCLUSIONS: High PD-L1 expression in SDC was strongly associated with unfavorable prognosis, indicating that PD-1/PD-L1 inhibitors could be effective in SDC.

Copy number gain in recurrent anaplastic lymphoma kinase (ALK) rearrangement-lung adenocarcinoma in the pleural effusion.

Copy number gain (CNG), which includes both numerical and structural chromosomal abnormalities, has been investigated in many human cancers. We report a case of recurrence of anaplastic lymphoma kinase (ALK) rearrangement-positive lung adenocarcinoma with increased cellular pleomorphism and ALK copy number in pleural effusion cytology, and retrospectively compared the recurrent tumor with the primary tumor in terms of cytological features, immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). The patient was a woman in her 50s who was found to have a 20 × 20 mm sized mass in the lung by chest computed tomography (CT), and was diagnosed with ALK rearrangement-positive lung adenocarcinoma. The patient was administered ALK inhibitors, such as alectinib, however 4 years later dissemination to the pleural effusion was detected. The smear was of high cellularity, and a predominant population of large-sized pleomorphic adenocarcinoma cells with prominent nucleoli was observed. On FISH and IHC using cell block material, ALK rearrangement and ALK protein expression were identified again, along with recurrent ALK adenocarcinoma cells, which were observed to have an increased ALK copy number compared with the primary ALK adenocarcinoma cells. On the other hand, there was no discrepancy in the expression of various biomarkers between the primary and corresponding recurrent tumor. The present case showed a marked difference in cytological findings and CNG between the primary and recurrent tumor, indicating that DNA aneuploidy may be related to morphological change such as transformation to bizarre pleomorphic cells in patients receiving alectinib treatment.

Large cell neuroendocrine carcinoma of the maxillary sinus on fine needle aspiration cytology: Report of a rare case with a focus on pitfalls in diagnosis.

Head and neck large cell neuroendocrine carcinoma (LCNEC) is a rare high-grade malignant tumor with neuroendocrine differentiation. We report a case of LCNEC causing difficulty in cytological diagnosis. A 60-year-old man with right-sided face pain presented with a swelling at the right cheek, and he complained of right nasal obstruction and lacrimation. Preoperative fine-needle aspiration cytology (FNAC) showed high cellularity, with a moderate number of clusters of tumor cells on an abundant necrotic background. The clusters were arranged in sheet structures with palisading, and were cohesive with overlapping. The tumor cells had comparatively abundant cytoplasm, with conspicuous large, irregular nucleoli with a fine granular chromatin pattern. Mitotic figures were observed easily. On immunocytochemistry using LBC smear, tumor cells were negative for p40. High-grade carcinoma other than non-keratinizing squamous cell carcinoma was suggested from these findings on FNAC. The pretreatment histological biopsy sample revealed tumor cells with solid growth pattern, necrotic materials and large polygonal cells with abundant cytoplasm, fine granular chromatin, and conspicuous nucleoli. Head and neck LCNEC with abundant cytoplasm, fine granular chromatin patterns, prominent nucleoli, and necrotic background were very characteristic of LCNEC. If considered carefully, these findings can enable us to exclude the majority of non-keratinizing squamous cell carcinomas, and FNAC using ancillary technique can be very useful for proper diagnosis.

Cytopathological and immunocytochemical findings of pancreatic anaplastic carcinoma with ZEB1 expression by means of touch imprint cytology.

Pancreatic anaplastic carcinoma (PAC) is rare and has an aggressive clinical course. We report an autopsy case of PAC focusing on the cytopathological characteristics of the tumor and immunocytochemical staining for vimentin, E-cadherin, and zinc finger E-box binding homeobox 1 (ZEB1), which markers are associated with epithelial markers of epithelial-mesenchymal transition (EMT). A 50-year-old woman presented to our hospital with a chief complaint of jaundice. A pancreatic head tumor and multiple liver nodules were detected on abdominal computed tomography. Biliary cytology under endoscopic retrograde cholangiopancreatography suggested ductal adenocarcinoma. Three months after admission, she died of multiorgan failure. At autopsy, touch imprint cytology using squash preparation of the pancreatic tumor identified two different cell types; numerous isolated malignant cells with large and pleomorphic nuclei and a few clusters showing irregularly overlapped nuclei and irregular contours within the necrotic background. Immunocytochemically, isolated cells were positive for vimentin and ZEB1, and negative for E-cadherin. Conversely, clusters were negative for vimentin and ZEB1, and positive for E-cadherin. Histologically, the tumor was composed of sarcomatous cells with small foci of adenocarcinoma, which were consistent with a diagnosis of PAC. Immunohistochemical staining of the adenocarcinoma and sarcomatous cells corresponded to those of the clusters and isolated malignant cells, respectively. Immunostaining of these EMT markers is useful to distinguish sarcomatous cells from adenocarcinoma and can contribute to the accurate diagnosis of pancreatic tumors with EMT.

HER2/HER3-positive metastatic salivary duct carcinoma in the pleural effusion: A case report.

Salivary duct carcinoma (SDC) is an aggressive form of salivary gland tumor, and SDC patients tend to be older men, more commonly in advanced stage with a poorer prognosis. Although the cytological characteristics of SDC on fine-needle aspiration cytology have been well-described at the primary site, they have not been explored in metastasis. Here we reported a case of HER2/HER3-positive metastatic SDC in the lung and pleural effusion. The patient was a man in his 50s who had undergone extended total parotidectomy in 2008. He was originally diagnosed as having HER2-positive left parotid SDC. Six years later a mass was discovered in the left lung by chest computed tomography (CT) and was diagnosed as metastatic SDC by both bronchial biopsy and cytology. Subsequently he had a recurrent SDC in the left pleural effusion and died of respiratory failure. Cytological findings from bronchial brushing smear showed small sheet clusters in a slightly necrotic background. In the pleural effusion cytology, tumor cells appeared as ball-like clusters of epithelioid cells with apocrine-like findings. In immunocytochemistry, HER3 of SDC cells in pleural effusion was significantly overexpressed relative to the matched primary tumor, even though HER2 amplification did not change. Cytological findings and HER family receptors differed between the primary and metastatic SDC. Therefore, molecular tests, such as protein expression and gene amplification using cytological specimens, may become important in future when determining therapy strategies in patients with distant metastasis.

Granulocyte colony-stimulating factor-producing pancreatic anaplastic carcinoma in ascitic fluid at initial diagnosis: A case report.

Granulocyte colony-stimulating factor (G-CSF)-producing pancreatic tumors are extremely rare. These tumors have an aggressive clinical course and no established treatment. Here, we report an autopsy case of G-CSF-production in pancreatic anaplastic carcinoma (PAC). A 72-year-old woman presented with a large pancreatic head mass and multiple liver metastases. Laboratory data showed leukocytosis (leukocyte count 113.3 × 103 /µL) and high serum G-CSF levels (441 pg/mL; normal range: <39.0 pg/mL). The ascitic fluid was submitted to our pathology laboratory at initial diagnosis. Cytopathology showed that smears from the ascitic fluid were highly cellular and contained numerous malignant cells, mainly in loose groupings. Occasional pseudoglandular formations and giant cells were also present. The malignant cells were round, and no spindle-shaped cells were visible. The nuclei were round to ovoid with coarsely granular chromatin and large prominent nucleoli. Upon immunocytochemistry, tumor cells were positive for G-CSF and vimentin; there was no E-cadherin expression. Histopathological examination of the tumor showed a mixed composition of adenocarcinomatous and sarcomatous regions. Upon immunohistochemistry, both components were positive for G-CSF. Few CD34-positive myeloblasts were observed in the bone marrow. Thus, we diagnosed this as a case of G-CSF production in PAC with leukocytosis. To the best of our knowledge, this is the first report on G-CSF expression immunocytochemically confirmed in PAC. Diagn. Cytopathol. 2017;45:463-467. © 2017 Wiley Periodicals, Inc.

Diagnostic utility of phosphorylated signal transducer and activator of transcription 5 immunostaining in the diagnosis of mammary analogue secretory carcinoma of the salivary gland: A comparative study of salivary gland cancers.

BACKGROUND: Mammary analogue secretory carcinoma (MASC) with an ETS variant gene 6 (ETV6)-neurotrophic tyrosine kinase receptor type 3 (NTRK3) translocation is a newly described type of salivary gland cancer. It is known that overexpression of signal transducer and activator of transcription 5a (STAT5a) occurs in secretory carcinoma of the breast and MASC, and STAT5a expression may be related to the ETV6-NTRK3 translocation. It was hypothesized that phosphorylated signal transducer and activator of transcription 5 (p-STAT5) might be specifically expressed in MASC of the salivary gland. METHODS: The expression of p-STAT5 and mammaglobin (MMG) was examined with immunohistochemistry (IHC)/immunocytochemistry (ICC) in tissue sections from 58 salivary gland cancers (8 MASCs and 50 other salivary gland cancers) and in cytological smears from 17 salivary gland cancers (7 MASCs with paired histologic samples and 10 other salivary gland cancers). RESULTS: p-STAT5 IHC was clearly increased in MASC versus normal salivary gland tissue and other salivary gland cancers. p-STAT5 expression was found in 7 of 8 MASCs (87.5%) and in none of the 50 other salivary gland cancers (0%) by IHC. On cytology, p-STAT5 expression was found in all cases of MASC (7 of 7 or 100%) but in none of the 10 other salivary gland cancers (0%) by ICC. The expression rate of MMG by histology and cytology was higher than that of p-STAT5 in the other salivary gland cancers. CONCLUSIONS: p-STAT5 might be useful as a detection marker of MASC in the differential diagnosis of salivary gland cancers, and initial screening with p-STAT5 IHC/ICC, combined with auxiliary fluorescence in situ hybridization confirmation, is a reliable, economical approach to identifying MASC of the salivary gland.

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.

Neurogenic pulmonary edema following Cryptococcal meningoencephalitis associated with HIV infection.

Neurogenic pulmonary edema (NPE) is a clinical syndrome characterized by the acute onset of pulmonary edema following a significant central nervous system insult. Only a few cases of NPE after Cryptococcal meningitis have been reported. We report a case of NPE following Cryptococcal meningoencephalitis. A 40-year-old man with no medical history was hospitalized for disturbance of consciousness. Blood glucose level was 124 mg/dL. Non-contrast head computed tomography showed no abnormalities. Lumbar puncture revealed a pressure of over 300 mm H2 O and cerebrospinal fluid (CSF) confirmed a white blood cell count of 65/mm(3) . The CSF glucose level was 0 mg/dL. The patient was empirically started on treatment for presumptive bacterial and viral meningitis. Four days after, the patient died in a sudden severe pulmonary edema. Autopsy was performed. We found at autopsy a brain edema with small hemorrhage of the right basal ganglia, severe pulmonary edema and mild cardiomegaly. Histologically, dilated Virchow-Robin spaces, crowded with Cryptococci were observed. In the right basal ganglia, Virchow-Robin spaces were destroyed with hemorrhage and Cryptococci spread to parenchyma of the brain. No inflammatory reaction of the lung was seen. Finally, acute pulmonary edema in this case was diagnosed as NPE following Cryptococcal meningoencephalitis. After autopsy, we found that he was positive for serum antibodies to human immunodeficiency virus.

Heterogeneity of anaplastic lymphoma kinase gene rearrangement in non-small-cell lung carcinomas: a comparative study between small biopsy and excision samples.

INTRODUCTION: The standard diagnostic method for echinoderm microtubule-associated protein-like 4-anaplastic lymphoma receptor tyrosine kinase translocation is fluorescence in situ hybridization (FISH). Recently, immunohistochemistry (IHC) has been reported as a potential method in screening for anaplastic lymphoma kinase (ALK)-positive non-small-cell lung carcinomas (NSCLC), whereas several authors have reported a discordance between FISH and IHC results. We investigated the heterogeneity of ALK gene rearrangement in excision specimens by FISH and also examined whether the FISH score of ALK gene rearrangement corresponded in excision and biopsy samples from the same patient. METHODS: Twenty ALK IHC-positive patients including six patients treated with crizotinib therapy were evaluated for the presence of ALK FISH. For evaluation of heterogeneity of ALK gene rearrangement in excision specimens, we defined six to 10 observation areas in each case, and the number of ALK FISH positive observation areas (≥15% rearrangement detected) was investigated. ALK FISH score in small biopsy samples was classified as positive (≥15% rearrangement detected), equivocal (5-14% rearrangement detected), or negative (<4% rearrangement detected). RESULTS: Of a total of 64 tumor observation areas from nine excision specimens, 50 areas were positive for ALK gene rearrangement (81.8%). In the comparison of excision and small biopsy samples, all excision specimens were ALK FISH-positive (100%; 6 of 6), whereas only three of the small biopsy samples in these patients were positive (50%; 3 of 6), two were equivocal (33%; 2 of 6), and one was negative (17%; 1 of 6). The two equivocal patients received crizotinib and showed a response. CONCLUSION: ALK gene rearrangement heterogeneity was observed in NSCLC specimens by FISH. Our findings suggested that IHC-positive/FISH-equivocal cases should not be considered true "false-negatives" when a small biopsy sample was used for ALK analysis.

Evaluation of immunohistochemistry using two different antibodies and procedures for primary lung adenocarcinoma harboring anaplastic lymphoma kinase rearrangement.

Rearrangements of anaplastic lymphoma kinase (ALK) have been recently identified in non-small cell lung carcinomas. Previous studies have revealed characteristic features, including adenocarcinoma histology and mucin production, in ALK-positive lung carcinoma. The present study evaluated immunohistochemistry (IHC) in ALK-positive lung carcinoma using two different antibodies, clone 5A4 and D5F3, and compared the results. On the basis of the aforementioned characteristic features, out of 359 primary lung carcinomas, the ALK status of 14 adenocarcinomas was screened using the intercalated antibody-enhanced polymer (iAEP) method with antibody 5A4, and this was compared with the ALK status obtained using rabbit monoclonal antibody D5F3 and fluorescence in situ hybridization for ALK. Eight cases were demonstrated to be ALK-positive by IHC. Seven cases exhibited ALK rearrangement, which was demonstrated by fluorescence in situ hybridization. The IHC for ALK obtained using D5F3 was comparable with that of the iAEP and exhibited low heterogeneity. This finding suggests that IHC for ALK could be useful in limited tissue samples, such as biopsy specimens or cytology, for the screening of ALK-positive lung carcinoma. In the present study, it was demonstrated that IHC with ALK monoclonal antibody D5F3 was useful for screening lung adenocarcinoma harboring ALK rearrangement.

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.