Cellular debris on negative liquid-based cytology cervicovaginal smears.

OBJECTIVES: To determine the prevalence of cellular debris (CD) on benign cervicovaginal liquid-based cytology (LBC) smears and which factors predict the presence and larger amount of CD. METHODS: Cervicovaginal smears evaluated as negative for intraepithelial lesion or malignancy (NILM) between 1 January and 31 March 2020 were retrospectively reviewed to record the presence and amount of CD. All smears were prepared with the SurePath platform. Patient ages and past medical and surgical histories were also retrieved. Multivariate regression analyses were performed to find positive predictors of a larger amount of CD. RESULTS: Three hundred forty-nine NILM smears were included in this study. The cohort consisted of 222 cervical smears (CS), and 127 vaginal smears (VS) taken from patients who had undergone hysterectomy. Overall, CD was observed in 111 (31.8%) cases. The positive predictors of CD were increasing age, specimen type (VS compared to CS), history of chemotherapy or radiation therapy (CRT), and more than mild background inflammation. Among the VS group, CD was present in 64 cases (50.4%) regardless of the time between the hysterectomy and specimen collection. Positive predictors in the VS group were age and more than mild inflammation. By contrast, the prevalence of CD in the CS group was 21.2%, and age was the only positive predictor. Histories of CRT, conisation, and inflammation were not statistically significant positive predictors for CD among CS. CONCLUSIONS: Cellular debris could be seen in as much as 50% of NILM smears taken after hysterectomy, regardless of the time since the procedure. Increasing age was a positive predictor of the presence and a larger quantity of CD. These findings are helpful when evaluating smears with moderate to abundant debris in the background with questionable cellular atypia.

Insulinoma-associated protein 1 (INSM1) is a useful marker for pancreatic neuroendocrine tumor.

Insulinoma-associated protein 1 (INSM1) is an important biomarker of Achaete-scute homolog-like 1-driven pathways. For diagnosis of pancreatic neuroendocrine tumors (PanNET), chromogranin A (CGA), synaptophysin (SYP), and neural cell adhesion molecule (NCAM) were also considered as potential biomarkers. However, it is often difficult to diagnose it immunohistochemically. Hence, we examined the expression pattern of INSM1 in pancreatic solid tumors. We detected INSM1, CGA, SYP, and NCAM immunohistochemically, in 27 cases of NET [pure type: 25 cases, mixed adenoneuroendocrine carcinoma (MANEC): 2 cases]. We included 5 cases of solid-pseudopapillary neoplasm (SPN), 7 cases of acinar cell carcinoma (ACC), and 15 cases of pancreatic ductal adenocarcinoma (PDAC) as the control group. Nuclear expression of INSM1 was found in all PanNET pure type cases. However, expression of INSM1 was negative in PDAC, ACC, and SPN in all cases, whereas faint expression was seen in the cytoplasm from SPN. MANEC comprises of two components: neuroendocrine carcinoma and adenocarcinoma components. The NET component was positive for INSM1 expression, whereas the PDAC component does not express INSM1, which aids in distinguishing these components. Our results suggest that INSM1 is a useful immunohistochemical marker for diagnosing pancreatic neuroendocrine tumor.

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.

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.

The correlation between FDG uptake and biological molecular markers in pancreatic cancer patients.

PURPOSE: We examined whether fluorine-18 fluorodeoxyglucose (FDG) uptake is related to the mammalian target of rapamycin (mTOR) signal pathway and its related proteins in pancreatic cancer patients. METHODS: We retrospectively studied 53 pancreatic cancer patients who underwent FDG positron emission tomography (PET) or FDG PET/CT, and complete curative surgical resection. The SUV max, the tumor to nontumor activity of pancreas [T/N (P)] ratio and the T/N of liver [T/N (L)] ratio were calculated. The expressions of glucose transporter-1(Glut-1) and mTOR pathway proteins in pancreas cell lines were examined by immune blots. Excised tumor tissue was analyzed by immunohistochemistry using monoclonal antibodies for Glut-1, epidermal growth factor receptor (EGFR), mTOR, p70S6kinase (p70S6) and S6 ribosomal protein (S6). RESULTS: The expressions of Glut-1, EGFR and p70S6 were significantly correlated with the SUV max, T/N (P) ratio and T/N (L) ratio. The expressions of mTOR and S6 were not correlated with all parameters. The expression of Glut-1 was positively correlated with the expressions of EGFR and p70S6, but not with mTOR or S6. S6 was positively correlated with p70S6. CONCLUSIONS: Glut-1, EGFR and p70S6 expressions are associated with the FDG uptake mechanism of pancreatic cancer. FDG uptake may predict the levels of EGFR and p70S6 expressions, and FDG uptake reflects glucose metabolism and cancer progression.

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.

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.

Evaluation of endoscopic cytological diagnosis of unresectable pancreatic cancer prior to and after the introduction of endoscopic ultrasound-guided fine-needle aspiration.

With the advances in the multidisciplinary treatment of pancreatic cancer (PC) over the last few years, it is crucial to obtain a histopathological diagnosis prior to treatment. Histopathological diagnosis for unresectable PC is currently performed with endoscopic retrograde cholangiopancreatography (ERCP) in combination with endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). We retrospectively assessed the results of these two methods and investigated diagnostic performance according to the location of the lesion and the complications. This study was conducted on a series of 263 consecutive cases of unresectable PC diagnosed with endoscopic cytology. Up to 2006, ERCP-guided cytology (group A) was performed as the first choice for the diagnosis of PC. EUS-FNA was introduced in 2007 and became the first choice thereafter (group B), except in cases with obstructive jaundice, in which ERCP-guided cytology during endoscopic biliary stenting (EBS) remains the first choice. There were statistically significant differences in the overall cancer-positive rate between groups A and B (60.4 vs. 75.3%, P=0.01). The cancer-positive rate in the pancreatic body and tail was significantly higher in group B (59.5 vs. 83.3%, P=0.005), whereas there were no significant differences regarding cancer of the pancreatic head. The complication rate was 4.95% in group A and 3.09% in group B (P=0.448). The endoscopic cytology cancer-positive rate in unresectable PC cases was increased as a result of the introduction of EUS-FNA. In conclusion, we recommend performing EUS-FNA in combination with ERCP-guided cytology in cases with a lesion in the pancreatic head that requires EBS.

Evaluation of endoscopic transpapillary brushing cytology for the diagnosis of bile duct cancer based on the histopathologic findings.

BACKGROUND AND AIM: Diagnosis of the bile duct cancer still needs more accuracy. Studies on endoscopic retrograde cholangiopancreatography (ERCP)-guided brushing cytology were carried to evaluate the role of the endoscopic transpapillary brushing cytology for the diagnosis of bile duct cancer. PATIENTS AND METHOD: The study involved 76 consecutive patients who underwent ERCP-guided bile duct cytology for the diagnosis of bile duct cancer from 2008 to August 2012. Three types of cytological specimens were obtained using different sampling methods, i.e., bile aspiration cytology (BAC), brush tip cytology (BTC), and post brushing bile cytology (PBC), to investigate their diagnostic abilities, and comparatively studied with each macroscopic type of the surgically resected specimens. RESULTS: The cancer-positive rate was 67.1 % (BAC alone: 41.9 %), and the use of BTC and PBC in addition to BAC yielded a statistically significant increase of the cancer-positive rate (p = 0.0031). In 34 resected cases, the cancer-positive rate in relation to the macroscopic type was improved by the addition of BTC and PBC to BAC alone for the papillary (87.5 vs. 40.0 %, p = 0.071) and nodular (100 vs. 70.0 %, p = 0.0603) types, but not for the flat type (62.5 vs. 57.1 %; p = 0.7651). CONCLUSION: The diagnostic ability of ERCP-guided brushing cytology could be improved by the addition of PBC. However, the cancer-positive rate was the lowest for the flat type of bile duct cancer.

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.

Potential usefulness of mucin immunohistochemical staining of preoperative pancreatic biopsy or juice cytology specimens in the determination of treatment strategies for intraductal papillary mucinous neoplasm.

We classified resected intraductal papillary mucinous neoplasms (IPMNs) into four subtypes (gastric, intestinal, pancreatobiliary and oncocytic) according to their morphological features and mucin expression, determined their clinicopathological characteristics and investigated the possibility of preoperatively diagnosing these subtypes. Sixty resected tumors, 4 preoperative tumor biopsies and 10 preoperative pancreatic juice cytology specimens were analyzed. The gastric and intestinal types accounted for the majority of IPMNs. Non-gastric type IPMNs were of high-grade malignancy. Many of the pancreatobiliary-type IPMNs were in an advanced stage and were associated with a poor prognosis. The results of mucin immunohistochemical staining of preoperative biopsy and surgically resected specimens were in agreement with each other, and in close agreement with those for pancreatic juice cytology specimens obtained from 10 patients during endoscopic retrograde cholangiopancreatography (ERCP). The immunostaining of preoperative biopsy specimens and ERCP-obtained pancreatic juice cytology specimens may be useful in the differential diagnosis of gastric and intestinal types of IPMN. If such techniques enable the preoperative diagnosis of IPMN subtypes, their use in combination with conventional preoperative imaging modalities may lead to surgical treatment best suited for the biological characteristics of the four subtypes.

Clinicopathological significance of hypoxia-inducible factor-1 alpha (HIF-1α) expression in gastric cancer.

BACKGROUND: Hypoxia is a common feature of rapidly growing solid tumors. Therefore, cellular adaptation to hypoxia and altered glucose metabolism are fundamental to the biology of cancer cells. Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor for more than 60 genes recognized to control the delivery of oxygen and nutrients through the induction of angiogenesis and glycolysis under hypoxic conditions. Therefore, inhibition of the expression of HIF-1α can be expected to be potentially tumor-specific molecular target-based therapy. In this study, we evaluated the significance of HIF-1α expression in relationship to clinicopathological factors, prognosis, vascular endothelial growth factor (VEGF) expression, and microvessel density (MVD). METHODS: Paraffin-embedded tumor specimens from 128 patients who underwent gastrectomy at Kurume University from 2004 to 2005 were used to assess the clinical significance of HIF-1α expression. We used the ABC method to perform an immunohistochemical analysis of the HIF-1α and VEGF expression. RESULTS: Eighty-four (65.6%) of gastric cancer specimens were positive for HIF-1α expression. Multivariate analysis showed that histology, depth of invasion, VEGF expression, and MVD were significantly associated with HIF-1α expression. On relapse-free and overall survival curves, the HIF-1α-negative group was significantly higher than the HIF-1α-positive group. Moreover, HIF-1α(+)/VEGF(+) patients had the worst prognosis. HIF-1α expression was identified as a significant predictor of relapse-free survival and overall survival by multivariate Cox's proportional hazard analyses. CONCLUSION: Overexpression of HIF-1α was found to be an indicator of poor prognosis for patients with gastric cancer and was significantly correlated with histology, depth of invasion, VEGF, and MVD.

Decreased expression of insulin and increased expression of pancreatic transcription factor PDX-1 in islets in patients with liver cirrhosis: a comparative investigation using human autopsy specimens.

BACKGROUND: Glucose intolerance in patients with liver cirrhosis (LC), known as hepatogenous diabetes, is thought to be distinct from type 2 diabetes (T2DM) in some aspects. Hyperinsulinemia and/or insulin resistance in liver disease is associated with hepatocarcinogenesis, growth of hepatocellular carcinoma, and poor prognosis. However, the pathophysiological processes in islets that are responsible for hyperinsulinemia in LC are still not precisely known. Therefore, we investigated the histopathological differences in islets of Langerhans cells between LC and T2DM. METHODS: A total of 35 human autopsy pancreatic tissue samples were used in this study (control, n = 18; T2DM, n = 6; LC, n = 11). The expression of insulin, glucagon, somatostatin, pancreatic duodenal homeobox-1 (PDX-1), proliferating cell nuclear antigen (PCNA), and Ki-67 was examined using immunohistochemistry and quantitated by image analysis. RESULTS: Islet hypertrophy and a significant increase in PCNA-positive cells in islets were observed in the tissues from LC cases. The insulin-positive areas in islets were significantly decreased in LC cases compared with control and T2DM cases (P = 0.001, P = 0.035, respectively), whereas the PDX-1-positive area was significantly increased in LC cases (P = 0.001) compared with the control. Furthermore, disorganization of pancreatic endocrine cells and nucleocytoplasmic translocation of PDX-1 were both seen in the LC subjects. CONCLUSIONS: In LC, islets undergo hypertrophy and exhibit paradoxical expression of insulin and PDX-1. In the subjects autopsied, insulin expression was decreased, whereas expression of the pancreatic transcription factor PDX-1 was increased in LC. These results point to important distinctions between LC and T2DM.

A diagnostic algorithm using EGFR mutation-specific antibodies for rapid response EGFR-TKI treatment in patients with non-small cell lung cancer.

BACKGROUND: We previously reported that EGFR mutation-specific antibodies performed well in immunohisto/cytochemical analysis. Assessment of EGFR mutation status for EGFR-TKIs (tyrosin kinase inhibitors) treatment of non-small cell lung cancer (NSCLC) patients can be performed by DNA-based assay. To establish a testing algorithm for EGFR mutation status in NSCLC patients, we utilized the peptide nucleic acid-locked nucleic acid (PNA-LNA) PCR clamp assay to determine the EGFR mutation, and immunostaining to detect the delE746-A750 and L858R mutation protein. PATIENTS AND METHODS: One hundred thirty-three patients with NSCLC were examined by immunostaining with EGFR mutation-specific antibodies, and by the PNA-LNA PCR clamp assay, using histological or cytological samples. The expression levels of immunostaining were classified as positive (score 2+), negative (score 0) or equivocal (score 1+), indicating questionable, negative or weak expression. Of these patients, 42 NSCLC patients received EGFR-TKIs treatment and we analyzed whether expression of mutant EGFR proteins was correlated with progression-free survival in patients with NSCLC treated with EGFR-TKIs. RESULTS: In the 133 samples, positive, negative and equivocal results for EGFR mutation-specific antibodies were observed in 37 patients (27.8%), 85 patients (63.9%) and 11 patients (8.3%), respectively. Thirty-seven patients showed positive EGFR expression by immunostaining, and 35 (94.6%) of these also tested positive in the DNA-based assay. Of 85 EGFR-negative patients by immunostaining, 77 (90.6%) also tested negative in the DNA-based assay. Of the 11 patients with equivocal immunostaining results, DNA-based assay detected EGFR mutation in 8 (72.7%) patients. Immunostaining for the EGFR mutation-specific antibodies showed a sensitivity of 81.4%, specificity of 97.5%, positive predictive value of 94.6% and negative predictive value of 90.6%, excluding the 11 patients with equivocal results. In NSCLC patients treated with EGFR-TKIs, the progression-free survival after the start of EGFR-TKIs treatment was significantly longer in patients with EGFR positive expression than in those with equivocal and negative expression (P=0.002). CONCLUSIONS: Our results suggest that patients testing positive for EGFR mutations by immunostaining are good candidates for rapid response EGFR-TKI therapy. Immunostaining for EGFR mutation-specific antibodies is a new test for EGFR-TKI inhibition and could be a useful indicator with regard to patient management.

Intraductal neoplasm of the intrahepatic bile duct: clinicopathological study of 24 cases.

AIM: To investigate the clinicopathological features of intraductal neoplasm of the intrahepatic bile duct (INihB). METHODS: Clinicopathological features of 24 cases of INihB, which were previously diagnosed as biliary papillomatosis or intraductal growth of intrahepatic biliary neoplasm, were reviewed. Mucin immunohistochemistry was performed for mucin (MUC)1, MUC2, MUC5AC and MUC6. Ki-67, P53 and ß-catenin immunoreactivity were also examined. We categorized each tumor as adenoma (low grade), borderline (intermediate grade), and malignant (carcinoma in situ, high grade including tumors with microinvasion). RESULTS: Among 24 cases of INihB, we identified 24 tumors. Twenty of 24 tumors (83%) were composed of a papillary structure; the same feature observed in intraductal papillary neoplasm of the bile duct (IPNB). In contrast, the remaining four tumors (17%) showed both tubular and papillary structures. In three of the four tumors (75%), macroscopic mucin secretion was limited but microscopic intracellular mucin was evident. Histologically, 16 tumors (67%) were malignant, three (12%) were borderline, and five (21%) were adenoma. Microinvasion was found in four cases (17%). Immunohistochemical analysis revealed that MUC1 was not expressed in the borderline/adenoma group but was expressed only in malignant lesions (P = 0.0095). Ki-67 labeling index (LI) was significantly higher in the malignant group than in the borderline/adenoma group (22.2 ± 15.5 vs 7.5 ± 6.3, P < 0.01). In the 16 malignant cases, expression of MUC5AC showed borderline significant association with high Ki-67 LI (P = 0.0622). Nuclear expression of ß-catenin was observed in two (8%) of the 24 tumors, and these two tumors also showed MUC1 expression. P53 was negative in all tumors. CONCLUSION: Some cases of INihB have a tubular structure, and are subcategorized as IPNB with tubular structure. MUC1 expression in INihB correlates positively with degree of malignancy.

NDRG1/Cap43/Drg-1 may predict tumor angiogenesis and poor outcome in patients with lung cancer.

OBJECTIVE: Expression of N-myc downstream-regulated gene 1 (NDRG1)/Cap43 is a prognostic indicator of human malignancies according to the tumor type in which it occurs. We investigated how NDRG1/Cap43 could affect tumor growth and angiogenesis in non-small-cell lung cancer (NSCLC) in vivo using an animal experimental model, and also how it could affect tumor angiogenesis and prognosis in NSCLC patients. METHODS AND RESULTS: Knockdown of NDRG1/Cap43 in lung cancer cells using a specific small interfering RNA resulted in growth rates in culture that were similar to those of counterpart control cells, but decreased tumor growth rates in vivo markedly. Stable NDRG1/Cap43 knockdown did not induce consistent changes in the expression of Epidermal growth factor receptor (EGFR) family proteins and c-Met in two human lung cancer cell lines in vitro. However, cell lines with NDRG1/Cap43 knockdown showed markedly decreased production of the potent angiogenic factors vascular endothelial growth factor-A and interleukin-8. Cells with knockdown of NDRG1/Cap43 showed marked reduction of tumor-induced angiogenesis. Using immunohistochemistry, we examined 182 surgically resected specimens of NSCLC for expression of NDRG1/Cap43 and tumor angiogenesis. High microvessel density in the tumor was significantly associated with nuclear positivity for NDRG1/Cap43 in both adenocarcinoma (p = 0.003) and squamous cell carcinoma (p=0.041). For both adenocarcinoma (p = 0.031) and squamous cell carcinoma (p=0.034), the survival curve of patients negative for nuclear NDRG1/Cap43 expression differed significantly from that of patients who were positive. CONCLUSION: Therefore, the expression of NDRG1/Cap43 may be predictive of tumor angiogenesis and poor prognosis in NSCLC.

The utility of a novel antibody in the pathological diagnosis of pancreatic acinar cell carcinoma.

AIMS: Acinar cell carcinomas (ACCs) are rare tumours of the exocrine pancreas accounting for about 1-2% of all pancreatic neoplasms in adults. It is therefore difficult to come across a large number of ACC cases in a single medical institution, and only a few serial studies have been published. Since ACCs present a wide variety of morphological patterns, immunohistochemical analysis is useful. In this study, the authors established a novel monoclonal antibody 2P-1-2-1 by means of a subtractive immunisation method. METHODS: Immunohistochemical staining was performed using 50 primary pancreatic tumors, including 7 ACCs, 7 neuroendocrine tumours (NETs), 5 solid-pseudopapillary neoplasms (SPNs), and 31 ductal carcinomas and organs other than the pancreas. RESULTS: Non-neoplastic acinar cells were stained diffusely, but epithelial cells of the pancreatic duct and the islets of Langerhans were not stained. In pancreatic tumours, all the seven ACCs were diffusely positive for the 2P-1-2-1 antibody. However, no positive staining was found in other pancreatic tumours including NETs, SPNs and ductal adenocarcinomas. The sensitivity and specificity of the 2P-1-2-1 antibody for ACCs were both 100%. In other organs studied, positive staining was observed only in the ectopic pancreas. CONCLUSIONS: It was shown that the 2P-1-2-1 antibody specifically stained the pancreatic acinar cells and tumours of acinar cell origin, such as ACCs. Although it remains unclear at this time to which proteins the monoclonal antibody 2P-1-2-1 is directed, it is suggested to be useful for the pathological diagnosis of ACCs and for the exclusion of other pancreatic tumours.