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Aims: Knowledge regarding the genetic features of ampullary carcinoma (AC) in European patients is limited. The utility of tumour markers for the establishment of a malignant diagnosis in biopsies from the ampullary region has not been fully elucidated. We aimed to describe the clinical, pathological, immunohistochemical (IHC) and genetic features of a Danish series of surgically resected ACs., Methods: Surgically resected ACs (n=59) were examined regarding (1) clinicopathological features, (2) histological subtypes, (3) expression of IMP3, maspin, MUC5AC and S100P and (4) next-generation sequencing using a hybrid capture-based platform (Illumina HiSeq2500), including 315 cancer-related genes plus introns from 28 genes often rearranged or altered in cancer. Tumour mutational burden (TMB) and microsatellite instability (MSI) were also evaluated., Results: Pancreatobiliary adenocarcinomas (PB-AC), intestinal adenocarcinomas (INT-AC), other ampullary tumours and mixed adenocarcinomas represented 45.8%, 23.7%, 16.9% and 13.6%. The proportion of IHC-positive ACs (score ≥2) was: Maspin (94.9%), IMP3 (67.8%), S100P (39.0%) and MUC5AC (18.6%). Most frequently altered genes were TP53 (59.3%), KRAS (40.7%), APC (27.8%), SMAD4 (20.4%), CDKN2A (16.7%) and ARID2 / PIK3CA (each 11.1%). MUC5AC and S100P were frequently expressed in PB-AC, APC alterations frequent in INT-AC, SOX9 alterations were exclusive in INT-AC and MDM2 and FRS2 alterations in PB-AC. Four of 49 ACs (8.2%) were TMB-high/MSI-high and showed loss of MLH1 and PMS2., Conclusions: PB-AC was the most frequent histological subtype of AC. Maspin and IMP3 were the IHC tumour markers with the highest sensitivity. Adenocarcinoma subtypes differed regarding several genetic alterations, whose predictive value remains to be evaluated., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Mixed neuroendocrine-nonneuroendocrine neoplasm (MiNEN) consisting of adenoma and well-differentiated neuroendocrine tumor (NET) has been recently defined as "MANET." However, the clinico-pathologic and pathogenetic features of this entity are not thoroughly studied. We examined the clinico-pathologic features of 12 MANETs by expanding their p53 and β-catenin expression profiles as well as the presence of microsatellite instability and KRAS, BRAF, and PIK3CA mutations in the 2 tumor components. In all cases, the adenomatous component represented the larger part of the lesions and the NET was localized in the deep central portion of polyps. In 9 cases the latter was represented by NET G1, in 2 by NET G2, and in 1 by NET G3. In all cases, the glandular and NET components were intimately admixed, with zone of transition between the tumor components. The NET component was p53 negative in all cases and 3 of 8 cases showed variable nuclear positivity for β-catenin. All patients with follow-up data were alive and free of disease after a mean follow-up time of 9 years. No mutations in KRAS, BRAF, and PIK3CA genes and no microsatellite instability were found in both tumor components. Review of the literature also identified 59 previously reported MANETs and no tumor-related death has been found. Like mixed adenoneuroendocrine carcinomas, a high-grade malignant form of MiNENs with a poorly differentiated neuroendocrine carcinoma component, a common origin for both tumor constituents may be hypothesized. Moreover, the current series provides evidence that MANET is an indolent disease that needs to be distinguished from aggressive high-grade MiNENs.

Cutaneous metastases from an adenocarcinoma of the Ampulla of Vater are very rare, with only a few cases previously reported. We present here an additional case in a 57-year-old woman who complained of a painful growth on her frontal scalp that she had noticed 4 months earlier. Her medical history included an ampullary adenocarcinoma, which was diagnosed 4 years ago, excised through a Whipple procedure, and treated using chemotherapy and radiotherapy. The scalp biopsy showed a dermal and epidermotropic well-differentiated glandular neoplasm with abundant neutrophils within the luminae of the tumoral glands. The tumor failed to express p63 and cytokeratin 5/6, whereas it was intensively positive for CK7 and E-cadherin. CDX2 expression was weak and focal. The immunohistochemical expression of DNA mismatch-repair proteins (MSH2, MSH6, MLH1, and PMS2) was preserved. Despite oncological treatment, the patient developed multiple cutaneous metastases during the ensuing several months, and eventually died 6 years after her initial diagnosis with widespread metastases.

Neural lesions occur uncommonly in the gastroenteropancreaticobiliary tract. However, due to the growing number of screening colonoscopy procedures, polypoid neural lesions of the colon are being recognised increasingly and range from benign tumours to high-grade malignant neoplasms. Morphological variability of neural tumours can be wide, although some entities share pathological features, and, as such, these lesions can be diagnostically challenging. We review the spectrum of pathology of neural tumours in the gastroenteropancreaticobiliary tract, with the goal of providing a practical approach for practising surgical pathologists., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background: Periodontal pathogens have been linked to oral and gastrointestinal (orodigestive) carcinogenesis. However, the exact mechanisms remain unknown. Treponema denticola (Td) is associated with severe periodontitis, a chronic inflammatory disease leading to tooth loss. The anaerobic spirochete Td is an invasive bacteria due to its major virulence factor chymotrypsin-like proteinase. Here we aimed to investigate the presence of Td chymotrypsin-like proteinase (Td-CTLP) in major orodigestive tumours and to elucidate potential mechanisms for Td to contribute to carcinogenesis., Methods: The presence of Td-CTLP within orodigestive tumour tissues was examined using immunohistochemistry. Oral, tonsillar, and oesophageal squamous cell carcinomas, alongside gastric, pancreatic, and colon adenocarcinomas were stained with a Td-CTLP-specific antibody. Gingival tissue from periodontitis patients served as positive controls. SDS-PAGE and immunoblot were used to analyse the immumodulatory activity of Td-CTLP in vitro., Results: Td-CTLP was present in majority of orodigestive tumour samples. Td-CTLP was found to convert pro MMP-8 and -9 into their active forms. In addition, Td-CTLP was able to degrade the proteinase inhibitors TIMP-1, TIMP-2, and α-1-antichymotrypsin, as well as complement C1q., Conclusions: Because of its presence within tumours and regulatory activity on proteins critical for the regulation of tumour microenvironment and inflammation, the Td-CTLP may contribute to orodigestive carcinogenesis.

Poorly differentiated neuroendocrine carcinoma of the digestive system has a dismal prognosis with limited treatment options. This study aimed to investigate expression of the PD-1/PD-L1 pathway in these tumors. Thirty-seven patients with a poorly differentiated neuroendocrine carcinoma of the digestive system were identified. Their electronic medical records, pathology reports, and pathology slides were reviewed for demographics, clinical history, and pathologic features. Tumor sections were immunohistochemically labeled for PD-1 and PD-L1, and expression of PD-1 and PD-L1 on tumor and tumor-associated immune cells was analyzed and compared between small cell and large cell neuroendocrine carcinomas. The mean age of patients was 61 years old with 18 men and 19 women. The colorectum (n=20) was the most common primary site; other primary sites included the pancreaticobiliary system, esophagus, stomach, duodenum, and ampulla. Expression of PD-1 was detected on tumor cells (n=6, 16%) as well as on tumor-associated immune cells (n=23, 63%). The 6 cases with PD-1 expression on tumor cells also had the expression on immune cells. Expression of PD-L1 was visualized on tumor cells in 5 cases (14%) and on tumor-associated immune cells in 10 cases (27%). There was no difference in PD-1 and PD-L1 expression between small cell and large cell neuroendocrine carcinomas. In conclusion, PD-1/PD-L1 expression is a frequent occurrence in poorly differentiated neuroendocrine carcinomas of the digestive system. Checkpoint blockade targeting the PD-1/PD-L1 pathway may have a potential role in treating patients with this disease., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Well-differentiated gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rare tumors with varying metastatic potential. The underlying molecular basis for metastasis by GEP-NETs remains undefined., Methods: Quantitative PCR and immunohistochemistry (IHC) staining for ubiquitin carboxyl-terminal esterase L1 (UCHL1) gene and protein expression was performed on a group of localized and metastatic well-differentiated GEP-NET samples acquired from a prospectively maintained tissue bank. The ability of extent of UCHL1 IHC staining to differentiate localized and metastatic tumors was compared with Ki-67 index., Results: Among 46 total samples, UCHL1 expression at both the gene and protein level was significantly greater among localized GEP-NETs compared with metastatic tumors and metastases (p < 0.001). Hypermethylation of the UCHL1 promoter was commonly observed among metastatic primary tumors and metastases (those with the lowest UCHL1 expression) but not among localized tumors (p < 0.001). Poor staining (<50 %) for UCHL1 was observed in 27 % of localized tumors compared with 87 % of metastatic tumors (p = 0.001). The presence of <50 % staining for UCHL1 was 88 % sensitive and 73 % specific for identifying metastatic disease. In contrast, there was no association between Ki-67 index and metastatic disease. In multivariable analysis, only UCHL1 staining <50 % [odds ratio (OR) 24.5, p = 0.035] and vascular invasion (OR 38.4, p = 0.03) were independent risk factors for metastatic disease at the time of initial surgery., Conclusions: Loss of UCHL1 expression by CpG promoter hypermethylation is associated with metastatic GEP-NETs. Extent of UCHL1 staining should be explored as a potentially clinically useful adjunct to Ki-67 index in evaluating GEP-NETs for aggressive features.

Cadherin 17 is a member of a multigene family of calcium-dependent, transmembrane proteins that mediates cell-cell adhesion, plays important roles during embryogenesis, and is crucial for tissue morphogenesis and maintenance. Cadherin 17 is exclusively expressed in the epithelial cells of embryonic and adult small intestine and colon, and pancreatic ducts. It has also been reported to be frequently expressed in adenocarcinomas arising in the gastrointestinal tract and pancreas. Owing to its restricted expression in these groups of tumors, cadherin 17 has proven to be a useful immunohistochemical marker for assisting in distinguishing these neoplasms from other malignancies with which they may be confused.

Distinguishing reactive mesothelial cells from metastatic disease, typically adenocarcinoma, in effusion cytology can be challenging at times. We currently use a panel of immunocytochemical markers for select cases including MOC-31 and BerEp4, but difficulties still exist. Enhancer of zeste homologue 2 (EZH2) plays important roles in epigenetic silencing and cell cycle regulation and is upregulated in a wide variety of malignancies. Thus, we hypothesized that EZH2 immunocytochemistry, which to our knowledge has not yet been reported on cytology material, might serve as a unique marker of malignancy in morphologically equivocal effusion specimens by highlighting aberrant protein expression in malignant cells. A total of 96 (48 benign and 48 malignant) effusion cases were selected retrospectively from our department archives. All malignant cases were metastatic adenocarcinomas except for three high grade neuroendocrine carcinomas (two lungs and one ovary), one cervical squamous cell carcinoma, and one epithelioid endometrial stromal sarcoma. The 48 benign cases were all negative for EZH2, and 43 of 48 malignant effusions were positive. As a solitary marker, EZH2 exhibited a sensitivity of 90% and a specificity of 100% (P < 0.0001). EZH2 functioned as a unique and accurate marker of malignancy in this series of effusions. Relative to published data, EZH2 demonstrated a sensitivity comparable to MOC-31 and superior to BerEp4, and a specificity superior to both of these commonly used immunostains. Thus, EZH2 is likely to be of great value as an adjunct to morphology in diagnosing malignancy in effusion specimens., (Copyright © 2013 Wiley Periodicals, Inc.)

Extragastrointestinal stromal tumors (EGISTs) are rare tumors located outside the gastrointestinal tract. While curable resection is accepted as a noninvasive EGIST treatment, the therapeutic strategy for invasive EGISTs has not yet been established. The present report is the first to show a case of invasive EGIST completely resected after downsizing the tumor with imatinib treatment. A 69-year-old female had multiple masses adjacent to the stomach and ileocecum. The primary lesion measured 18 cm in size and had invaded the stomach, pancreas and liver. The histological findings of fine-needle aspiration samples revealed a proliferation of dysplastic spindle cells that exhibited immunoreactivity for anti-c-kit antibodies. The masses were therefore diagnosed as multiple GISTs with invasion to other organs, with origin difficult to determine at the time. Nineteen months after the imatinib treatment, the tumors were downsized and distinct from the stomach, pancreas and liver. Accordingly, the tumors were regarded to be EGISTs derived from the mesentery. Because they slightly regressed 26 months after treatment, surgery was applied to remove the EGISTs. The intraoperative findings showed no invasive signs, and the tumors were completely removed. The histological findings revealed the presence of dysplastic and c-kit-positive spindle cells in the tumor with an MIB-I index of more than 5%, resulting in a final diagnosis of high-risk EGIST derived from the mesentery. No recurrence was detected for 16 months after resection. In conclusion, preoperative treatment with imatinib followed by curable resection is a feasible option to cure invasive EGISTs.

Background/aims: In gastroenteropancreatic neuroendocrine tumors (GEP-NETs), primary lesions cannot be resected when the patients have highly advanced disease or when the primary sites are undefined. Such GEP-NETs cannot be evaluated with Ki-67 or the mitotic index. The aim of this study was to examine the prognosis of GEP-NETs that were ungraded by WHO G1-3 grading (U-NET group)., Methodology: Between 2000 and 2011, 75 patients with sporadic GEP-NETs were treated at our institution. The prognosis of patients graded as new WHO grading (G-NET group) was compared with that of the U-NET group. Cox proportional hazard regression analyses were performed to estimate the risk factors for overall survival (OS)., Results: Overall 1-, 3- and 5-year survival rates were 90.7%, 79.9% and 74.9%, respectively. The odds ratio (OR) of patients with synchronous liver metastasis and U-NET was 1.73 (p=0.01) and 5.84 (p=0.002), respectively. Multivariate analyses of OS according to baseline characteristics revealed the only independent risk factor to be U-NET (OR, 3.95; p=0.02)., Conclusions: The malignant potential of U-NET may be no less than that of G-NET, while WHO-G3 patients have the worst prognoses in the G-NET group.

We evaluated CA19-9 as a marker of various malignancies and compared the results of 2 commercial immunoassays. The Abbott ARCHITECT i2000 and Roche cobas 410 immunoassays were used on 500 consecutive samples to evaluate the frequency of positive results by cancer type and the correlation between assays. The patients were tested before or after surgery and/or during chemotherapy. The rate of results exceeding conventional thresholds was 92.3% in pancreatic cancer, 36.8% in gastric cancer, and ranged from 3.0% to 35.9% in other tumors. Agreement (90.6%) and correlation (R(2) = 0.865) between the 2 assays were good and the frequency of highly discordant results was low (6/500). In some cases, interference by heterophilic antibodies was demonstrated. The 2 methods were comparable in diagnostic accuracy and had good correlation but are not interchangeable. Patients should always be monitored for CA19-9 with the same method and it should be indicated in the report.

Unlabelled: Neuroendocrine tumors (NET) are known for an overexpression of somatostatin receptors (SSTR). In light of very few and partially contradictory publications, the present study aims to achieve a definite immunohistochemical (IHC) quantification and assessment of the distribution of all five SSTR-subtypes on NET and to evaluate an implementable scoring system, comparing the immunoreactive score of Remmele and Stegner (IRS) to the Her2-score. In 21 patients 40 different tumor tissues were IHC analysed using polyclonal antibodies for SSTR1 and 3-5 and the monoclonal antibody UMB-1 for SSTR2A. SSTR expression was quantitatively evaluated according to HER2-score and IRS, correlated among each other and to the maximum standardized uptake value (SUVmax) in tumor lesions as measured by PET/CT using 68Ga-DOTA-NOC., Results: According to the IRS, the expression of SSTR2A and 3 predominated equally with 84%, followed by SSTR4 (44%) and SSTR1 and 5 (32%). With the Her2-scoring system the most frequent subtype was found to be SSTR2A (68%), followed by SSTR3 (64%), SSTR1 (44%), SSTR5 (40%), and SSTR4 (36%). The IRS-classification and the Her2-score were found to be statistically comparable, and their correlation is highly significant for each SSTR assessment (p<0.01)., Conclusion: The results of the analyses revealed heterogeneous expression patterns. SSTR2A and 3 were highly expressed, demonstrating the importance of SSTR for diagnostics and therapy. Relatively high frequency of SSTR3 and 4 on NET give reasons to try pansomatostatin analogues for therapy rather than concentrating only on the SSTR2A. Statistically, none of the immunohistochemical scores was superior. However, due the heterogeneity of the cytoplasmic staining justice we propose the IRS as a uniform scoring scheme for IHC NET diagnostic.

Bile was shown to collect proteins known as potential cancer biomarkers. Thorough proteomic analysis of bile is of particular interest to search for new, more sensitive and more specific, biomarkers of cancers affecting the biliary tract and surrounding organs, such as the pancreas and the liver. Therefore, extending the knowledge of the bile proteome is highly relevant, but this has proved technically difficult. In this study, we describe a strategy that circumvents problems related to the biochemical complexity of this sample and the presence of high concentrations of interfering substances. Bile collected from a patient suffering from a biliary stenosis caused by a pancreatic adenocarcinoma was fractionated by a differential centrifugation scheme, involving a stepwise increase in centrifugation speeds. Pellets and the final supernatant were further fractionated by polyacrylamide gel electrophoresis and proteins were in-gel digested prior to LC-MS/MS analysis. This approach allowed the identification of 445 unique proteins with at least two peptides (812 proteins if single-hit proteins were included), which represents a 3-fold increase in the knowledge of bile proteome. The subsequent literature comparison revealed that numerous biliary proteins identified in this sample were related to pancreas cancer. Immunoblot analysis of some known tumor markers revealed that they were preferentially associated with the soluble fraction rather than with pellets containing cellular components.

The need for standards in the management of patients with endocrine tumors of the digestive system prompted the European Neuroendocrine Tumor Society (ENETS) to organize a first Consensus Conference, which was held in Frascati (Rome) and was based on the recently published ENETS guidelines on the diagnosis and treatment of digestive neuroendocrine tumors (NET). Here, we report the tumor-node-metastasis proposal for foregut NETs of the stomach, duodenum, and pancreas that was designed, discussed, and consensually approved at this conference. In addition, we report the proposal for a working formulation for the grading of digestive NETs based on mitotic count and Ki-67 index. This proposal, which needs to be validated, is meant to help clinicians in the stratification, treatment, and follow-up of patients.

Objective: To investigate whether the needle washing could yield sufficient cells for tumor marker (TM) measurements as an ancillary technique to ensure the accuracy of fine needle aspiration cytology (FNAC) of tumors., Study Design: After obtaining preliminary data that aspirated tumor cells within a 22-gauge needle could be collected by washing it with distilled water for TM measurements, we studied tumor cell numbers and TM values obtained by washing a 22-gauge needle directly after tumor aspiration and another needle after FNAC., Results: Using 8 resected hepatobiliary and pancreatic carcinomas, the used needles yielded 16.8+/-10.5 x 10(4) cells per milliliter. Used needles from 6 adenocarcinomas expelled 479.2+/-406.5 ng/mL of carcinoembryonic antigen, and 6,561.3+/-5,713.1 ng/mL of CA 19-9, while the needles from 2 hepatomas showed normal values of those markers., Conclusion: A needle used for FNAC contains sufficient cells for TM measurements, which can be ancillary to the differential diagnosis.

Serum tumor markers are useful for detection and diagnosis of cancer. Recent advances in cellular and molecular biology have developed procedures of immunohistochemistry including high sensitivity staining and epitope retrieval. Using the immunohistochemical analyses, we can detect various tumor markers, i.e., not only serum tumor markers (serum protein, carbohydrates), but also cellular skeletons, lymphocyte surface antigens, cytoplasmic markers, oncogene products and cell adhesion molecules. This article focuses on several immunohistochemical tumor markers. Carcinoembryonic antigen(CEA) is one of the good markers of colorectal cancer. Recent studies have demonstrated that CEA may function as a metastatic potentiator by different pathway, such as modulation of immune responses, facilitation of intercellular adhesion and cellular migration. CA19-9 (sialyl Le antigen), a member of a family of high molecular weight glycoproteins, was originally described as a gastrointestinal- and pancreatic-specific tumor marker. Recent studies have demonstrated that sialyl Le is a ligand for E-selectin and may play an important role in tumor metastasis. Stromal immunoreactivities of CEA or CA19-9 were correlated with lymph node metastasis and/or vascular invasion. p53 is one of the most important tumor suppressor genes, and the p53 gene product is known to regulate cell growth and proliferation. Mutation of the p53 gene can be detected immunohistochemically as overexpression of its protein in the nucleus. Diffuse p53 immunoreactivity was a histological marker of adenocarcinoma. In conclusion, immunohistochemical tumor markers are useful for histopathological diagnosis and can be prognostic predictors of cancer.

Endocrine tumors (ETs) of the digestive system produce several growth factors including acidic and basic fibroblast growth factors (aFGF and bFGF, respectively), which are thought to be involved in the growth of tumor cells and in the proliferation of tumor stromal cells. Their actions depend on binding to four specific receptors--FGFR1, FGFR2, FGFR3, and FGFR4--whose distribution in normal endocrine cells and related tumors of the gastroenteropancreatic (GEP) system has previously been examined. Formalin-fixed, paraffin-embedded normal tissues and 60 well-characterized GEP endocrine tumors were immunostained using specific antibodies directed against various GEP hormones, aFGF, FGFR1, FGFR2, FGFR3, and FGFR4. Acidic FGF immunoreactivity (IR) was found in gut EC cells; FGFR1 immunoreactivity in rare duodenal endocrine cells and in pancreatic A cells; FGFR2 immunoreactivity in gastric and duodenal G cells, pancreatic B cells, and rectal EC cells; FGFR3 immunoreactivity in duodenal G cells; and FGFR4 immunoreactivity in rectal L cells and in pancreatic B, PP, and A cells. Immunoreactivity for at least one of the four FGFRs was found in all tumors, independently of FGFR expression in the putative cell of origin. EC cell tumors, which were all positive for aFGF, were found to express at least three different FGFRs. FGFRs also were localized in the stromal cells of all the tumors examined. The tumor stroma was more abundant in EC cell tumors than in other types of neoplasms. The results suggest that aFGF-FGFR interaction may be involved in the modulation of normal endocrine cell functions and in the regulation of tumor growth and stromal proliferation of EC cell carcinoids.

Receiver operating characteristic (ROC) curves are limited when several diagnostic tests are available, mainly due to the problems of multiplicity and inter-relationships between the different tests. The program presented in this paper uses the generalised ROC criteria, as well as its confidence interval, obtained from the non-central F distribution, as a possible solution to this problem. This criterion corresponds to the best linear combination of the test for which the area under the ROC curve is maximal. Quantified marker values are assumed to follow a multivariate normal distribution but not necessarily with equal variances for two populations. Other options include Box-Cox variable transformations, QQ-plots, interactive graphics associated with changes in sensitivity and specificity as a function of the cut-off. We provide an example to illustrate the usefulness of data transformation and of how linear combination of markers can significantly improve discriminative power. This finding highlights potential difficulties with methods that reject individual markers based on univariate analyses.

Unlabelled: This study aimed to evaluate the diagnostic utility of 111In-DTPA-D-Phe1-octreotide scintigraphy in the different situations that can be present when an examination is requested during the clinical course of the carcinoid tumor (CT)., Materials and Methods: We have performed 41 scintigraphies with 111In-octreotide (145-185 MBq) in 35 patients (19 females and 16 males) with clinically suspected or confirmed CT. The patients were classified into five groups: Group A: Indolent symptoms of CT (n=9); B: CT staging located in lung (n=4), stomach (n=2), cecum (n=1), thymus (n=1) and pancreas (n=1); C: Carcinoid syndrome (n=1); D: CT staging after surgery located in pancreas (n=1), ovary (n=1), cecum (n=1), stomach (n=1), appendix (n=1) and ileum (n=1); and E: Post-treatment follow-up (n=13), with CT located in bronchial tree (n=5), small intestine (n=3), appendix (n=2), thymus (n=1), ovary (n=1) and unknown primary tumor (n=1). Three patients of this group had one scintigraphic study before the treatment. Head and neck, thorax and abdomen images were obtained at 4 and 24 h in all of the patients and SPECT images of the abdomen (n=14), thorax (n=10), and brain (n=1) were obtained at 24 h in 25 patients., Results: Group A: In the 3 patients with a positive scintigraphy, the definitive diagnosis was meningioma, Hurtle cell's carcinoma and lung adenocarcinoma. The clinical follow-up in the six other patients, at least during one year, did not show any evidence of CT. Group B: Six of the 9 CT were detected with the scintigraphy. In 2 cases of bronchial CT, the scan showed sarcoidotic regional lymph node involvement and CT hepatic and bone metastases, respectively. Group C: The scintigraphy detected hepatic metastases from an unknown primary tumor. Group D: The scintigraphy was positive in 3 cases (hepatic or/and abdominal metastases) and was normal in the other 3. The scintigraphy was negative in one patient with peritoneal metastases. Group E: The scintigraphy was normal in 7 patients in concordance with the clinical follow-up. In 3 patients with a scintigraphy performed prior to treatment, the scintigraphy detected recurrence (thymic CT), progression of the metastatic disease (ovarian CT) and partial regression of the hepatic metastases (carcinoid syndrome). In the three other patients, the scintigraphy showed metastases located in liver in one patient and hepatic and extra-hepatic metastases in the two other patients. The sensitivity and specificity of 111In-Octreotide in the detection of the primary tumor and metastases were 72% and 84% respectively., Conclusions: The 111In-Octreotide scintigraphy has a low diagnostic utility in patients with indolent symptoms of CT. However, it is the first line of diagnosis for the staging of the CT and to evaluate the follow up after therapy.

Objective: To study the expression of thyroid transcription factor 1 (TTF-1) and cytokeratin 20 (CK20) in pulmonary small cell carcinomas, extrapulmonary small cell carcinomas, and Merkel cell carcinomas, and thereby determine whether these markers are helpful in distinguishing these 3 groups of small cell neuroendocrine carcinomas., Materials and Methods: Immunostaining for TTF-1 and CK20 was performed in 102 cases of small cell carcinoma (pulmonary, 52; extrapulmonary, 50) and 23 cases of Merkel cell carcinoma. The results for the 3 groups were compared., Results: Thyroid transcription factor 1 was expressed in 82.7% of pulmonary small cell carcinomas, 42.0% of extrapulmonary small cell carcinomas (range, 33.3--53.3% for the various sites), and 0% of Merkel cell carcinomas. Cytokeratin 20 staining was consistently negative in pulmonary small cell carcinomas, and positive in 4.0% of extrapulmonary small cell carcinomas and 100% of Merkel cell carcinomas., Conclusions: Immunostaining for TTF-1, especially when combined with immunostaining for CK20, can aid in the distinction between Merkel cell carcinoma and small cell carcinoma (both pulmonary and extrapulmonary). However, in individual cases, these markers cannot be used to distinguish between pulmonary and extrapulmonary small cell carcinomas due to the extensive overlap in immunophenotypes.

The gastrointestinal tract including oral cavity is the most common location of extranodal lymphomas. In this retrospective study, the histomorphological, immunohistochemical and clinical features of 21 Macedonian cases with diagnosed malignant lymphomas were investigated. The series included 15 males and 6 females, mean age 44 (4-78) years. The most common locations were hard palate (n = 7), gastric site (n = 5), small intestinal wall (n = 2), large intestinal wall (n = 5), and lingual root (n = 2). All cases were B cell lymphomas, 23.8% of them low grade B cell lymphoma of mucosa associated lymphoid tissue, 4.7% mantle cell lymphoma, 47.6% diffuse large cell lymphoma, and 23.8% Burkitt type lymphoma. There was no T cell lymphoma. Most of the cases were positive for CD20 and CD79a. Monoclonality was confirmed by light chain restriction, except for nine cases where it failed due to poor tissue preservation. The fact that eight cases were in the clinically advanced third and fourth stage implied a conclusion that not only primary non-Hodgkin's lymphomas but also secondary lesions could invade the gastrointestinal tract. Immunohistochemical staining was helpful in differentiation between benign and malignant infiltration in low grade lymphomas, and in distinguishing diffuse large cell lymphomas from undifferentiated epithelial neoplasms.

Activin A and inhibin A, first isolated from the ovary, are dimeric proteins able to modulate pituitary FSH secretion. Inhibin A is a heterodimer composed of one alpha-subunit and one betaA-subunit (alpha-betaA), while activin A is a homodimer of the betaA-subunit (betaA-betaA). Their identification in several tissues has suggested that they have numerous physiological functions, acting as either paracrine or autocrine factors. The aim of this study was to evaluate the expression of activin A and inhibin A in normal endocrine cells and in 70 endocrine tumours from different sites in the gastro-entero-pancreatic system, using specific monoclonal antibodies directed against the alpha- and betaA-subunits of inhibin/activin. Immunoreactivity for the betaA-subunit, but not for the alpha-subunit, was observed in normal G, EC, and GIP cells of the antrum and duodenum, and in pancreatic A cells. BetaA-subunit expression was observed in G cell and A cell tumours, and in a few insulinomas and ileal EC cell carcinoids. The alpha-subunit was found in rare cells in 7 of the 70 tumours and was colocalized with the betaA-subunit in only 1 tumor. Specific types of endocrine cells from the gut and pancreas appear to produce only activin A, a possible paracrine or autocrine modulator. Activin A is mainly produced by tumours derived from endocrine cells that normally express it.

Background: Human papillomavirus (HPVs) types 6 and 11, are frequently found in non-malignant anogenital condylomas and laryngeal papillomas. However, in an ongoing epidemiological study in Argentina in which 163 anogenital and aero-respiratory cancer biopsies were analyzed, several cases infected with low-risk HPVs could be detected., Methods: Tumor samples were analyzed by Southern blot hybridization, using HPVs 6, 11, 16, 18, 30, 31, 33 and 35 as probes, and polymerase chain reaction (PCR) with type-specific primers and probes., Results: Four invasive carcinomas containing HPV 6 or 11 could be detected (2.4%) by Southern blot technique. HPV 6 DNA was found in a penile carcinoma, a groin carcinoma, and in a tonsillar carcinoma. One cervical carcinoma harbored HPV 11 DNA. Using HPVs 6, 11, 16, 18 and 33 anticontamination primers and probes in PCR, no additional high-risk HPV types could be detected in these four cancers., Conclusion: This report shows the presence of low-risk HPVs (HPV 6 and 11) associated to malignant tumors in a frequency higher than usually observed. The data raise questions about which are the circumstances which may favor low-risk HPV related oncogenesis.

Tumor metastasis is one of the most life-threatening aspects of tumor progression in patients with cancer. One of the cell surface molecules that has been implicated to play an important role in tumor metastasis is CD44. Earlier results provide the initial optimism that CD44 isoform expression may be a marker for human cancers. However, more recent studies revealed that regulation of CD44 isoform expression is a complex and not well-understood phenomenon. Expression of CD44 in tumor cells can be regulated quantitatively by increasing the expression of one particular CD44 isoform or quantitatively by altering the expression of CD44 isoforms. Downregulation of CD44 is important in the metastasis of some tumor cells. We summarize some of the recent results on the potential of CD44 as a diagnostic or prognostic marker for patients with cancers.

Guanylin is a recently discovered peptide hormone that activates intestinal guanylate cyclase (GC-C) and thereby stimulates intestinal chloride secretion. Immunohistochemistry showed its presence in enterochromaffin (EC) cells of the gut. In vitro studies suggested that guanylin plays an important role in the endogenous modulation of intestinal salt and water secretion. In the present study the concentration of circulating immunoreactive (IR)-guanylin in plasma of patients with intestinal diarrhoea due to chronic bowel inflammation and patients with carcinoid tumours were measured with a specific radioimmunoassay. In 22 patients with Crohn's disease and eight patients with ulcerative colitis, plasma concentrations of IR-guanylin were 44 +/- 3 and 42 +/- 4 fmol mL-1, respectively. Levels were not different from that in 44 healthy volunteers suggesting that the circulating hormone is not involved in diarrhoea of these patients. In 17 patients with symptomatic carcinoid tumors the median concentration of circulating IR-guanylin was significantly enhanced (94 +/- 16 fmol mL-1, range 37-312 fmol mL-1). Immunohistochemistry revealed the presence of immunoreactive guanylin in carcinoid tissues, suggesting that these tumours co-release guanylin along with their usual resident hormone, serotonin. Enhanced local secretion of guanylin may play a causal role in diarrhoea of these patients and its elevation in plasma may be of diagnostic value in this type of endocrine tumours.

Background: It is now well documented that patients with squamous cell carcinoma of the upper aerodigestive tract frequently develop additional squamous cell carcinoma in the same field., Methods: p53 expression in 95 patients with multicentric squamous cell carcinoma and in squamous epithelia surrounding multicentric squamous cell carcinomas of the upper aerodigestive tract in 20 patients was examined by immunohistochemistry. In addition, p53 expression in 129 patients with supposedly unicentric squamous cell carcinoma and in squamous epithelia surrounding unicentric squamous cell carcinoma in 22 patients was also examined by immunohistochemistry., Results: Among the 95 patients with multicentric squamous cell carcinoma, 62 (65%) had a clearly positive reaction for p53 protein, whereas 56 (43%) of 129 patients with unicentric squamous cell carcinoma had a positive reaction for p53 protein. The frequency of positive nuclear p53 staining in multicentric squamous cell carcinoma appeared higher than that in unicentric squamous cell carcinoma. However, there was no significant difference between the two groups. Among the nondysplastic squamous epithelia surrounding multicentric squamous cell carcinomas in 20 patients, 12 (60%) were p53 positive, whereas only five (22%) of 22 patients with nondysplastic squamous epithelia surrounding unicentric squamous cell carcinomas were positive. The difference between the two groups was significant (P < 0.05)., Conclusions: The present results suggest that nuclear accumulation of p53 in the squamous epithelium surrounding multicentric squamous cell carcinoma is probably due to heavier exposure and increased susceptibility to mutagens of the affected individuals, although this remains to be verified.

Alterations in the normal glycosylation process are often associated with oncogenic transformation. Using an anti-Tn monoclonal antibody, MLS128, we have investigated the immunohistochemical localization of Tn antigen in normal and malignant tissues of the digestive tract. In normal tissues, MLS128 was immunoreactive with the squamous epithelium of the esophagus and was weakly reactive with the columnar epithelia of the stomach, duodenum, colon, bile duct and pancreatic duct. In malignant tissues, positive immunostaining was detected with high frequency (75%-100%) in carcinomas of the esophagus, stomach colon, biliary tract and pancreas, whereas 2 of 11 (18%) hepatocellular carcinomas were positive. Tn antigen was detected in the upper two-thirds of the normal squamous epithelium, and was often detected in squamous cell carcinomas with cancer pearls (keratinization). These results suggest that the expression of Tn antigen is related to the differentiation of squamous epithelium, or to keratinization. In normal columnar epithelial cells. Tn antigen was localized mainly to the Golgi area. This intracellular localization was preserved in well-differentiated papillary adenocarcinomas of the colon, but was lost in most cases of tubular adenocarcinomas.

Amylin was isolated from human insulinomas, but there has been only preliminary data regarding whether this peptide can also be detected in other types of gastroenteropancreatic endocrine tumors. In the present study, immunohistochemical staining of 87 gastroenteropancreatic endocrine tumors demonstrated amylin immunoreactivity in 21.8% of the neoplasmas. Thirteen of 15 insulinomas, three of 21 gastrinomas, two of 29 nonfunctioning tumors, and one of 18 carcinoids were amylin-immunoreactive. Seventeen of the 19 amylin-immunoreactive tumors were primarily located in the pancreas, but two tumors were found in the intestine. Measurements of amylin messenger RNA expression in a few tumors revealed amylin synthesis in these tumors. Amylin immunoreactivity did not correlate with invasion and metastasis. However, the rate of curative resections was significantly higher in amylin-immunoreactive tumors. These results demonstrate for the first time that amylin immunoreactivity is not restricted to insulinomas and can also occur rarely in endocrine tumors of the intestine.

Neuroendocrine tumors of the digestive system are slow growing neoplasms which often present with pronounced fibrosis around tumor cells and in the peritoneal cavity. In this report 30 midgut carcinoids and endocrine pancreatic tumors were examined for the expression of peptide growth factors and their receptors, both by immunohistochemistry and in situ hybridization. Our data indicate that multiple peptide growth factors, PDGF, TGF-beta, and bFGF are expressed by these tumors. PDGF was expressed on tumor cells and stroma in 70% of tissues examined. PDGF alpha-receptor was seen on clusters of tumor cells and occasionally on adjacent stroma, whereas PDGF beta-receptor was seen only in the stroma. Our data suggest that PDGF may be involved in the autocrine stimulation of tumor cells and stimulation of stromal cell growth through paracrine and possibly autocrine mechanism. In addition, tumor tissues express all three isoforms of TGF-beta in more than half of the tissues examined. Tumor cells produce small latent complexes causing an escape from potent inhibitory effect of TGF-beta and stimulation of stromal cell growth and matrix deposition through paracrine mechanism. bFGF, a potent stimulant of endothelial cell growth, was expressed by all tumor tissues examined. Our data suggest that multiple peptide growth factors may have an important role in tumor progression and desmoplastic reaction accompanying these tumors.

The multiple actions of somatostatin are mediated by specific membrane-bound receptors present in all somatostatin target tissues, such as brain, pituitary, pancreas, and gastrointestinal tract. Three different types of tissues in the human gastrointestinal tract express somatostatin receptors: (1) the gastrointestinal mucosa, (2) the peripheral nervous system, and (3) the gut-associated lymphoid tissue, where the receptors are preferentially located in germinal centers. In all these cases, somatostatin binding is of high affinity and specific for bioactive somatostatin analogs. Somatostatin receptors are also expressed in pathological states, particularly in neuroendocrine tumors of the gastrointestinal tract. Ninety percent of the carcinoids and a majority of islet-cell carcinomas, including their metastases, usually have a high density of somatostatin receptors. Only 10 percent of the colorectal carcinomas and none of the exocrine pancreatic carcinomas, however, contain somatostatin receptors. The somatostatin receptors in tumors are identified with in vitro binding methods or with in vivo imaging techniques; the latter allow the precise localization of the tumors and their metastases in the patients. Since somatostatin receptors in gastroenteropancreatic tumors are functional, their identification can be used to assess the therapeutic efficacy of octreotide to inhibit excessive hormone release in the patients.

Thirty-six patients underwent biopsy of clinically suspicious lesions of the mucosa of the upper aerodigestive tract. The biopsy material was evaluated histologically and cytologic smears out of the same lesion underwent quantitative DNA analysis using a numerical index derived from the single cell DNA content. In 30 patients, histologically diagnosed squamous cell cancer was confirmed by DNA analysis with the malignancy grade correlating with the morphologic differentiation of the tumor. Six lesions were histologically benign: i.e. dysplasia (n = 3), hyperplasia (n = 2) and chronic inflammation (n = 1). DNA analysis confirmed the benign nature in 4 cases, but in 2 cases of dysplasia, a diagnosis of malignancy was made. From these results, there appears to be an excellent correlation between DNA analysis and the histologic diagnosis of malignancy. It remains to be proven if this technique of DNA analysis will prove to be a more accurate determinant of malignant potential in premalignant conditions and a method to determine aggressiveness of behavior. An added advantage is that this technique can be performed on cytologic smears, without the need for incisional biopsy.

c-myc is a conserved cellular gene. The gene product is a nuclear-bound 62,000 molecular weight phosphoprotein (p62c-myc). Although p62c-myc levels have been measured in colorectal cancers, little is known about the expression of the protein in upper gastrointestinal tumours and tissues. Studies were performed on tumour and mucosal specimens from 87 patients with colorectal cancer, from two with polyposis coli, from six with squamous oesophageal carcinomas and from 18 with gastric carcinomas. The mean p62c-myc content was measured in units of fluorescence in the G1 diploid and G2 diploid peaks of the cell cycle by multiparameter flow cytometry using the 6E10 antibody. The nuclear p62c-myc content increased with DNA synthesis in tumours and mucosa. G2 levels of p62c-myc were higher in glandular mucosa than in adenocarcinomas. No differences in peak nuclear c-myc expression were found in relation to histological grade or to anatomical site of colorectal tumours. There was a broadly inverse relationship between G2 p62c-myc levels in tumours and mucosa and their in vivo 5-bromo-2'-deoxyuridine labelling indices. Nuclear p62c-myc levels are cell cycle related but the protein has not been shown to be a marker of increased tissue proliferation or of gastrointestinal malignancy. The reduction of the nuclear p62c-myc content of many adenocarcinoma cells compared with glandular mucosa cells suggests that reduced synthesis or nuclear retention of the normal protein may be a factor in the development of gastrointestinal adenocarcinomas, although the mechanism by which this may occur is not clear.

The immunohistochemical localization of DU-PAN-2 antigen and CA19-9 antigen in carcinomas of the digestive tract was studied using an immunoperoxidase technique. Staining for DU-PAN-2 antigen and CA19-9 antigen was observed in 104 (79%) and 96 (73%) of 131 carcinomas of the digestive tract, respectively. Diffuse staining (more than 20% of carcinoma cell stained) for DU-PAN-2 was detected in 14 of 21 (67%) pancreatic carcinomas and 11 of 19 (58%) carcinomas of the biliary tract (including cholangiocarcinoma). Diffuse staining for CA19-9 was detected in 15 (71%) of pancreatic carcinomas and nine (47%) of the carcinomas of the biliary tract. In colon carcinomas, no diffuse staining for DU-PAN-2 was observed, whereas diffuse staining for CA19-9 was found in 41%. There was a positive correlation between the differentiation degree (or grade) of the adenocarcinomas of the colon and the expression of CA19-9, but not that of DU-PAN-2. These immunohistochemical studies showed that DU-PAN-2 antigen is expressed diffusely in most cases of adenocarcinoma of the pancreas and biliary tract and is more specific for adenocarcinomas of the pancreas and biliary tract than CA19-9.