Incisionless fluorescent cholangiography (IFC): a pilot survey of surgeons on procedural familiarity, practices, and perceptions.

BACKGROUND: Incisionless fluorescent cholangiography (IFC) has recently been proven feasible, safe, and efficacious as an intraoperative procedure to help identify extrahepatic bile ducts during laparoscopic cholecystectomies (LC). We conducted a pilot survey of 51 surgeons attending an international conference who perform endoscopic cholecystectomies to identify their typical LC practices, and perceptions of IFC. METHODS: An international panel of ten IFC experts, all with > 500 prior IFC procedures and related research publications, convened during the 4th International Congress of Fluorescence-Guided Surgery in Boca Raton, Florida in February 2017. The panel was charged with developing questions about LC practices and experience with IFC, and perceptions regarding its advantages, barriers to use, and indications. These questions then were asked to other congress attendees during one of the didactic sessions using an online polling application. Attendees, who ranged from zero to considerable experience performing IFC, accessed the survey via their portable devices. RESULTS: Of the 51 survey participants, 51% were from North America; 77% identified themselves as general/minimally invasive surgeons, and roughly 60% performed under 50 cholecystectomies/year. Only 12% performed routine intraoperative cholangiography (IOC), while 72.3% routinely performed critical safety reviews. Thirty-five percent estimated that their institution's laparoscopic-to-open surgery conversion rate was > 1% during LC. Roughly 95% of respondents felt that surgeons should have access to a noninvasive method for evaluating extrahepatic biliary structures; 84% felt that the most advantageous characteristic of IFC is the lack of any biliary-tree incision; and 93.3% felt that IFC would have considerable educational value in surgical training programs; and 78% felt that any surgeon who performs LC could benefit. CONCLUSIONS: Surgeons who participated in our survey overwhelmingly recommended the routine use of IFC during laparoscopic cholecystectomy as a complimentary imaging technique. Prospective randomized clinical trials remain necessary to determine whether IFC reduces the incidence of bile duct injuries and other LC complications.

Randomized Trial of Near-infrared Incisionless Fluorescent Cholangiography.

BACKGROUND: Incisionless near-infrared fluorescent cholangiography (NIFC) is emerging as a promising tool to enhance the visualization of extrahepatic biliary structures during laparoscopic cholecystectomies. METHODS: We conducted a single-blind, randomized, 2-arm trial comparing the efficacy of NIFC (n = 321) versus white light (WL) alone (n = 318) during laparoscopic cholecystectomy. Using the KARL STORZ Image1 S imaging system with OPAL1 technology for NIR/ICG imaging, we evaluated the detection rate for 7 biliary structures-cystic duct (CD), right hepatic duct (RHD), common hepatic duct, common bile duct, cystic common bile duct junction, cystic gallbladder junction (CGJ), and accessory ducts -before and after surgical dissection. Secondary calculations included multivariable analysis for predictors of structure visualization and comparing intergroup biliary duct injury rates. RESULTS: Predissection detection rates were significantly superior in the NIFC group for all 7 biliary structures, ranging from 9.1% versus 2.9% to 66.6% versus 36.6% for the RHD and CD, respectively, with odds ratios ranging from 2.3 (95% CI 1.6-3.2) for the CGJ to 3.6 (1.6-9.3) for the RHD. After dissection, similar intergroup differences were observed for all structures except CD and CGJ, for which no differences were observed. Significant odds ratios ranged from 2.4 (1.7-3.5) for the common hepatic duct to 3.3 (1.3-10.4) for accessory ducts. Increased body mass index was associated with reduced detection of most structures in both groups, especially before dissection. Only 2 patients, both in the WL group, sustained a biliary duct injury. CONCLUSIONS: In a randomized controlled trial, NIFC was statistically superior to WL alone visualizing extrahepatic biliary structures during laparoscopic cholecystectomy. REGISTRATION NUMBER: NCT02702843.

Loss of heterozygosity at thymidylate synthase locus in Barrett's metaplasia, dysplasia, and carcinoma sequences.

BACKGROUND: Thymidylate synthase (TS) is known to have a unique 28 bp tandemly repeated sequence in the promoter region, and the majorities of subjects have a heterozygous double repeat/triple repeat genotype in their non-cancerous tissue. Loss of heterozygosity (LOH) at the TS locus is known to occur in cancer patients, but there is no evidence that it is present in precancerous tissue. The aim of this study was to analyze the frequency and timing of LOH at the TS locus in Barrett-associated adenocarcinoma (BA) and its precursory lesions, such as intestinal metaplasia (IM) and dysplasia. METHODS: One hundred twenty-three samples (including 37 with gastroesophageal reflux disease (GERD), 29 with IM, 13 with dysplasia, and 44 with BA) were obtained from 100 patients. Biopsies were obtained from the lower esophageal mucosa/IM/dysplasia/BA, when available. Normal squamous tissue from the upper esophagus was taken as a control. All tissues were analyzed for the TS genotype and TS mRNA expression using the real-time reverse-transcription polymerase chain reaction (RT-PCR) method after laser-capture microdissection. RESULTS: Among the patients with informative heterozygous genotype in their control samples, no sample with LOH at the TS locus was observed in the lower esophageal mucosa in GERD patients (0/22 samples). However, 6 out of 21 samples (28.6%) had LOH in IM, 2 of 7 (28.6%) in dysplasia, and 10 of 25 (40.0%) in BA. No significant difference in TS mRNA expression levels was observed between TS genotypes. CONCLUSION: Our results demonstrate that LOH is a relatively frequent and early event in the IM-BA sequence.

Dwarfs in disguise: multiple spinal abscesses and spondylodiscitis caused by an Enterococcus faecium small-colony variant.

Small-colony variants are slow-growing subpopulations of bacteria known to be involved in latent or recurrent infections, especially in deep-seated foci. Their atypical growth in small colonies can hamper prompt and correct identification in clinical specimens. Here, we present the first case of multiple spinal abscesses and spondylodiscitis associated with an Enterococcus faecium small-colony-variant in an immunocompetent patient. This case demonstrates the diagnostic challenges when encountering this phenotype in the diagnostic laboratory.

Acne inversa.

Acne inversa is a chronic inflammatory skin disease featuring cutaneous and subcutaneous nodular inflammation, fistula formation and discharge of foul-smelling secretions. The disease can lead to functional impairment and psychological problems. There is inflammation of the terminal hair follicles in intertriginous regions, especially perianal, axillary and inguinal areas. Less often there is submammary, periumbilical, retroauricular or nuchal involvement. Without treatment the disease is chronic and progressive. The causes of acne inversa are multifactorial and pathogenesis is still not well understood. Besides a positive family history, obesity and cigarette smoking are trigger factors. Early diagnosis and therapy of acne inversa saves the patient years of suffering. The most effective treatment is undoubtedly the radical wide excision of the affected areas. Local measures such as radiotherapy, photodynamic therapy and cryotherapy have provided little benefit; the same is true for systemic antibiotic treatment or hormonal therapy with anti-androgens. TNF-alpha antagonists seem to have a promising influence on the disease. Further studies investigating the effect of these substances on acne inversa are warranted.

Genomic profiling associated with recurrence in patients with rectal cancer treated with chemoradiation.

PURPOSE: Stage II and III adenocarcinoma of the rectum has an overall 5-year survival rate of approximately 50%, and tumor recurrence remains a major problem despite an improvement in local control through chemotherapy and radiation. The efficacy of chemoradiation therapy may be significantly compromised as a result of interindividual variations in clinical response and host toxicity. Therefore, it is imperative to identify those patients who will benefit from chemoradiation therapy and those who will develop recurrent disease. In this study, we tested whether a specific pattern of 21 polymorphisms in 18 genes involved in the critical pathways of cancer progression (i.e., drug metabolism, tumor microenvironment, cell cycle regulation, and DNA repair) will predict the risk of tumor recurrence in rectal cancer patients treated with chemoradiation. PATIENTS AND METHODS: A total of 90 patients with Stage II or III rectal cancer treated with chemoradiation were genotyped using polymerase chain reaction (PCR)-based techniques for 21 polymorphisms. RESULTS: A polymorphism in interleukin (IL)-8 was individually associated with risk of recurrence. Classification and regression tree analysis of all polymorphisms and clinical variables developed a risk tree including the following variables: node status, IL-8, intracellular adhesion molecule-1, transforming growth factor-beta, and fibroblast growth factor receptor 4. CONCLUSION: Genomic profiling may help to identify patients who are at high risk for developing tumor recurrence, and those who are more likely to benefit from chemoradiation therapy. A larger prospective study is needed to validate these preliminary data using germline polymorphisms on tumor recurrences in rectal cancer patients treated with chemoradiation.

Gene expression levels of epidermal growth factor receptor, survivin, and vascular endothelial growth factor as molecular markers of lymph node involvement in patients with locally advanced rectal cancer.

BACKGROUND: Patients diagnosed with locally advanced rectal cancer usually receive surgical resection and adjuvant chemoradiation therapy. Lymph node involvement is an important clinical prognostic factor affecting recurrence and survival. Few studies have explored molecular markers associated with lymph node involvement of rectal cancer. PATIENTS AND METHODS: Tissue was obtained from 59 patients with locally advanced rectal cancer who were treated with adjuvant chemoradiation therapy. We assessed messenger RNA (mRNA) levels of genes involved in pathways of angiogenesis (vascular endothelial growth factor [VEGF], cyclooxygenase-2), apoptosis (survivin), tumor growth and epidermal growth factor receptor (EGFR), DNA repair (ERCC1, Rad51), and the DNA synthesis in tumor tissue and tumor-adjacent normal tissue from paraffin-embedded samples using laser-capture microdissection methods. RESULTS: Twenty-four patients had no involvement of regional lymph nodes and 35 had lymph node metastases. In univariate analysis, patients with lymph node involvement had higher mRNA levels of VEGF and survivin in tumor tissue and EGFR in tumor-adjacent normal tissue compared with patients with no lymph node involvement (P < 0.1; t test). Multivariate analysis using recursive partitioning showed that mRNA levels of EGFR, survivin, and Rad51 are primarily responsible for delineating node positive from node negative. CONCLUSION: Gene expression of VEGF, survivin, and EGFR could be associated with lymph node involvement in patients with locally advanced rectal cancer. Further independent studies of those gene expression levels and lymph node involvement are warranted to better characterize the associations.

Identification of dysregulated genes in cutaneous squamous cell carcinoma.

Carcinogenesis is a multi-step process resulting from the accumulation of genetic mutations and subsequently leading to dysregulated genes, but the number and identity of differentially expressed genes in cutaneous squamous cell carcinoma (SCC) is unknown at present. In order to identify dysregulated genes, we examined the relative mRNA expression present in cutaneous SCC and its precursor lesion actinic keratosis (AK) by comparison to normal skin. Snap frozen biopsies from 20 specimens of normal skin, 10 AK, and 10 cutaneous SCC were examined. Total-RNA was extracted, reversely transcribed, and 14 genes were investigated using gene-specific intron-flanking primers and quantitative real-time reverse transcription PCR. Specificity was confirmed by sequencing of the PCR amplicons. Ten of 14 genes were significantly dysregulated in AK and/or cutaneous SCC by comparison to normal skin. The genes CNN2, COX4I1, COX5B, COX7C, CRLF3, CTSC, NDRG1, and LMNA showed increased expression in skin cancer (p < 0.02), while RPL15 and LGTN were down-regulated (p < 0.03). The genes differentially expressed during skin carcinogenesis may prove useful in order to understand the origin and progression of cutaneous SCC and for diagnostic approaches.

Intratumoral COX-2 gene expression is a predictive factor for colorectal cancer response to fluoropyrimidine-based chemotherapy.

PURPOSE: Cyclooxygenase-2 (COX-2) is generally elevated in tumors compared with normal tissue and apparently has an important role in tumor development. A number of studies have found high expression of COX-2 to be an unfavorable prognostic factor for overall survival in several cancers. However, the influence of COX-2 expression levels on tumor response to chemotherapy has been relatively little studied. The purpose of this study was to ascertain if COX-2 gene expression is associated with tumor response in the clinical treatment of colorectal cancer with the fluoropyrimidine-based therapy S-1. EXPERIMENTAL DESIGN: Patients with advanced (stage IV) colorectal cancer were treated with S-1 twice daily based on the patient's body surface area (BSA; BSA < 1.25 m2, 80 mg/d; 1.25 m2 < or = BSA < 1.5 m2, 100 mg/d; BSA > or = 1.5 m2, 120 mg/d) for 28 days followed by a 2-week period rest. mRNA was isolated from paraffin-embedded pretreatment primary tumor specimens and expression levels of COX-2 relative to beta-actin as the internal reference gene were measured using a quantitative reverse transcription-PCR (Taqman) system. RESULTS: The overall response rate in a group of 44 patients treated with S-1 was 40.9%. Sufficient tumor tissue was available from 40 of these patients for COX-2 mRNA quantitation. COX-2 gene expression was significantly lower in the responding tumors compared with the nonresponders (P = 0.012, Wilcoxon test). Patients with COX-2 values above the cutoff value of 3.28 x 10(-3) had a significantly shorter survival than those with COX-2 gene expressions below the cutoff value (adjusted P = 0.031). CONCLUSIONS: Intratumoral COX-2 gene expression is associated with likelihood of response to chemotherapy with S-1 and is a prognostic factor for survival of patients after the start of S-1 chemotherapy.

Survivin as a therapeutic target for radiation sensitization in lung cancer.

Expression of survivin is elevated in most malignancies, especially in radiation-resistant cell lines. In this study, we investigated how radiation affects survivin expression in primary endothelial cells as well as in malignant cell lines. We found that 3 Gy significantly reduced survivin protein level in human umbilical vein endothelial cells (HUVECs) but not in tumor cell lines. Flow cytometry studies suggest that the down-regulation of survivin is independent of cell cycle. In addition, survivin mRNA level was also down-regulatable by irradiation. However, it was abrogated by actinomycin D-mediated inhibition of gene transcription. Luciferase reporter gene assays suggest that irradiation suppressed the survivin promoter. p53 overexpression reduced survivin expression, but overexpression of a p53 mutant failed to abolish the radiation-induced down-regulation in HUVECs. Alteration of p53 status in Val138 lung cancer cell line also failed to restore the radiation-inducible down-regulation. Overexpression of survivin in 293 cells prevented apoptosis induced by irradiation and increased cell viability after irradiation. The inhibition of survivin using antisense oligonucleotides caused a significant decrease in cell viability of irradiated H460 lung cancer cells. These data suggest that radiation transcriptionally down-regulates survivin in HUVECs. This regulatory mechanism is defective in malignancies and is not mediated by p53. Survivin overexpression may lead to resistance to radiotherapy by inhibiting apoptosis and enhancing cell viability. The inhibition of survivin results in sensitization of H460 lung cancer cells to radiation. These studies suggest that survivin may be a target for cancer therapy.

A multigene expression panel for the molecular diagnosis of Barrett's esophagus and Barrett's adenocarcinoma of the esophagus.

In order to identify genes or combination of genes that have the power to discriminate between premalignant Barrett's esophagus and Barrett's associated adenocarcinoma, we analysed a panel of 23 genes using quantitative real-time RT-PCR (qRT-PCR, Taqman and bioinformatic tools. The genes chosen were either known to be associated with Barrett's carcinogenesis or were filtered from a previous cDNA microarray study on Barrett's adenocarcinoma. A total of 98 tissues, obtained from 19 patients with Barrett's esophagus (BE group) and 20 patients with Barrett's associated esophageal adenocarcinoma (EA group), were studied. Triplicate analysis for the full 23 gene of interest panel, and analysis of an internal control gene, was performed for all samples, for a total of more than 9016 single PCR reactions. We found distinct classes of gene expression patterns in the different types of tissues. The most informative genes clustered in six different classes and had significantly different expression levels in Barrett's esophagus tissues compared to adenocarcinoma tissues. Linear discriminant analysis (LDA) distinguished four genetically different groups. The normal squamous esophagus tissues from patients with BE or EA were not distinguishable from one another, but Barrett's esophagus tissues could be distinguished from adenocarcinoma tissues. Using the most informative genes, obtained from a logistic regression analysis, we were able to completely distinguish between benign Barrett's and Barrett's adenocarcinomas. This study provides the first non-array parallel mRNA quantitation analysis of a panel of genes in the Barrett's esophagus model of multistage carcinogenesis. Our results suggest that mRNA expression quantitation of a panel of genes can discriminate between premalignant and malignant Barrett's disease. Logistic regression and LDAs can be used to further identify, from the complete panel, gene subsets with the power to make these diagnostic distinctions. Expression analysis of a limited number of highly selected genes may have clinical usefulness for the treatment of patients with this disease.

Downregulation of TS, DPD, ERCC1, GST-Pi, EGFR, and HER2 gene expression after neoadjuvant three-modality treatment in patients with esophageal cancer.

BACKGROUND: To find out if neoadjuvant therapy could alter tumor response determinants that might affect tumor sensitivity to the treatment, we investigated intratumoral expressions of genes associated with chemosensitivity, radiosensitivity, or both before and after radiochemotherapy. STUDY DESIGN: Twenty-four patients with locally advanced, resectable esophageal cancer (cT2-4,Nx,M0) received neoadjuvant 5-FU/cisplatin/36 Gy treatment followed by transthoracic en bloc esophagectomy. Expression levels of thymidylate synthase, dihydropyrimidine dehydrogenase, excision repair cross-complementing gene 1 , glutathione S-transferase Pi, epidermal growth factor receptor, and HER2 were measured in matched preradiochemotherapy endoscopic tumor biopsies and in postradiochemotherapy resection specimens. mRNA was isolated from formalin-fixed, paraffin-embedded, laser microdissected tumor tissues, and a quantitative fluorescent dye real-time reverse transcription polymerase chain reaction system was used for gene expression measurement. RESULTS: There was a significant reduction in the expression levels of thymidylate synthase (p < 0.01), dihydropyrimidine dehydrogenase (p = 0.03), excision repair cross-complementing gene 1 (p < 0.01), glutathione S-transferase Pi (p = 0.03), HER2 (p < 0.01), and epidermal growth factor receptor (p = 0.04). The change in the levels of epidermal growth factor receptor mRNA in post- compared with pretreatment specimens was significantly associated with the histopathologic grade of regression (p = 0.01). CONCLUSIONS: The expression levels of a set of genes that are possible determinants of 5-FU/cisplatin/radiation therapy antitumor activity are significantly downregulated by neoadjuvant radiochemotherapy in esophageal cancer.

Osteopontin but not osteonectin messenger RNA expression is a prognostic marker in curatively resected non-small cell lung cancer.

PURPOSE: The purpose of this study was to better define the role of osteopontin (OPN) and osteonectin [also known as secreted protein acidic and rich in cysteine (SPARC)] in lung tumorigenesis by comparing the expressions of these genes in lung tumor tissue and matched normal tissue and by determining the prognostic significance of the gene expressions. EXPERIMENTAL DESIGN: Quantitative real-time reverse transcription-PCR was used to analyze OPN and SPARC mRNA expression in normal lung tissue and matching tumor samples from 82 patients with non-small cell lung cancer. Gene expression data for each patient were matched to survival data. RESULTS: The overall median mRNA expression level of OPN was about 20-fold higher in tumor tissues than in matching normal lung tissues (P < 0.001), whereas SPARC gene expression was not significantly different in both tissue types. Forty of 82 patients had high (>or=4.1) intratumoral OPN expression, and 15 of 82 patients had high (>or15.5) SPARC expression. High OPN expression in the tumor tissue was associated with inferior survival (P = 0.014), whereas high SPARC expression showed a trend toward longer survival (P = 0.095). The impact of high OPN and low SPARC expression on patient survival was additive (P = 0.001). CONCLUSIONS: The large increase in OPN expression in tumors compared with normal tissue and its association with survival suggest a role for OPN in lung tumorigenesis.

Loss of heterozygosity at the thymidylate synthase (TS) locus on chromosome 18 affects tumor response and survival in individuals heterozygous for a 28-bp polymorphism in the TS gene.

Thymidylate synthase (TS), the target enzyme of the fluoropyrimidine class of drugs, has a 28-bp repeat polymorphism in the promoter region that has been associated with response of tumors to 5-fluorouracil-based therapy. Patients homozygous for the double repeat (2R/2R) in the TS gene have an overall better outcome from treatment than patients homozygous for the triple repeat (3R/3R). However, due to loss of heterozygosity at the TS locus on chromosome 18 in cancer cells, heterozygous 2R/3R individuals can acquire the 2R/loss or the 3R/loss genotype in their tumors. The purpose of this study was to determine whether the response of colorectal cancer to fluoropyrimidine therapy is associated with the resulting tumor TS genotype when loss of heterozygosity occurs in tumor DNA. A total of 30 colorectal cancer patients treated with the fluoropyrimidine-based combination S-1, all of whom had stage IV disease, were studied. The response rate to S-1 in this group of patients was 13 of 30 (43%). The heterozygous 2R/3R genotype was found in 22 of 30 normal tissues, whereas 10 (45%) of the matched cancer tissues showed only the 2R-sequence band (2R/loss), and 7 cancer tissues (32%) showed only the 3R-sequence band (3R/loss). The response rate of the 2R/loss tumor genotype patients was 80% (8 of 10) compared with 14% (1 of 7) in the 3R/loss genotype group (P = 0.029). Patients with tumor 3R/loss genotypes had significantly lower survival than 2R/loss genotypes. Heterozygous patients with a 2R/loss tumor genotype had the same survival as 2R/2R patients, whereas patients with a 2R/3R tumor genotype had a short survival similar to homozygous 3R/3R genotypes. These results show that: (a) response to 5-fluorouracil-based therapy is determined by tumor genotype; and (b) the 3R repeat is a direct negative determinant of outcome.

Quantitative O(6)-methylguanine DNA methyltransferase methylation analysis in curatively resected non-small cell lung cancer: associations with clinical outcome.

PURPOSE: Hypermethylation of the O(6)-methylguanine DNA methyltransferase (MGMT) promoter region leads to transcriptional repression of the MGMT gene and is a common event in primary human neoplasia. The purpose of this study was to determine the frequency and clinical relevance of MGMT gene promoter hypermethylation in curatively resected non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: MGMT hypermethylation, expressed as the ratio between methylated MGMT to unmethylated MYOD1 in genomic DNA, was analyzed in normal and matching tumor tissue from 90 patients with NSCLC, and a control group of 10 patients without cancer using a methylation-specific fluorogenic Real-Time PCR (Taqman) system. RESULTS: Hypermethylation of the MGMT promoter was detected in 34 of 90 (38%) tumor specimens and 16 of 90 (18%) matching normal lung tissues of patients with NSCLC, and in 0 (0%) cases of the control group without lung cancer. The mean MGMT methylation level was significantly higher in tumor than in matching normal tissue (P < 0.001). MGMT methylation in normal tissue was always accompanied with MGMT methylation in matching tumor tissue. Patients without MGMT promoter hypermethylation showed a significantly better survival than patients with MGMT promoter hypermethylation (P = 0.017). Multivariate analysis revealed MGMT promoter methylation as an independent unfavorable prognostic factor (P = 0.030). CONCLUSIONS: MGMT promoter hypermethylation is a common event in patients with primary NSCLC. This epigenetic alteration is associated with inferior survival, suggesting that MGMT promoter hypermethylation might be an important biomarker for a biological aggressive disease in NSCLC.

Increased acid exposure in patients with gastroesophageal reflux disease influences cyclooxygenase-2 gene expression in the squamous epithelium of the lower esophagus.

HYPOTHESIS: Although genetic changes associated with the progression to Barrett esophagus and adenocarcinoma have been identified, changes in gene expression associated with gastroesophageal reflux disease have not been reported. We examined expression levels of several genes important in carcinogenesis and compared expression levels with alterations in esophageal acid exposure. PATIENTS, DESIGN, AND SETTING: Prospective analysis of 61 patients initially seen with reflux symptoms at a private academic hospital. INTERVENTIONS: Paired esophageal biopsy specimens of squamous epithelium 3 cm above the squamocolumnar junction. All patients had 24-hour pH monitoring performed. MAIN OUTCOME MEASURES: Cyclooxygenase (COX) 1, COX-2, thymidylate synthase, human telomerase reverse transcriptase (hTERT), Bcl-2 protein, survivin protein, secreted protein acidic and rich in cysteine (SPARC), tetraspan (TSPAN), and caudal-type homeobox transcription factor 2 (CDX2) messenger RNA expression analysis was performed on snap-frozen, microdissected tissue using a quantitative reverse transcriptase-polymerase chain reaction method. Linear regression and the Pearson product moment correlation were used to relate gene expression to parameters of the 24-hour pH record. RESULTS: Expression levels of COX-2 correlated positively with the 24-hour pH score (r = 0.25, P =.05). There was no correlation between the expression of other tested genes and esophageal acid exposure. There was also no significant increase in COX-2 expression in patients with esophagitis or in those who used nonsteroidal anti-inflammatory drugs. CONCLUSIONS: To our knowledge, these data provide among the first reported correlation of genetic changes and increased esophageal acid exposure in patients with gastroesophageal reflux symptoms. The changes in gene expression occur before any metaplastic changes in the tissue are apparent, and may in the future be useful in predicting which patients will progress through a metaplasia-dysplasia carcinoma sequence.

Quantitative, tissue-specific analysis of cyclooxygenase gene expression in the pathogenesis of Barrett's adenocarcinoma.

Cyclooxygenase (Cox-2) is implicated in the pathogenesis of many cancers including esophageal adenocarcinoma (EAC), whereas the role of the isoform Cox-1 in carcinogenesis is not well understood. To further elucidate the role of these factors in the development of EAC, we measured the gene expressions (mRNA levels) of Cox-2 and Cox-1 by real-time quantitative polymerase chain reaction (QRT-PCR) in tissues from normal esophagus with and without erosive gastroesophageal reflux disease (GERD), Barrett's esophagus (BE), dysplasia, adenocarcinoma, and in healthy gastric antrum. All tissues were purified by laser capture microdissection from endoscopic or surgical resection specimens. Median Cox-2 gene expression did not differ significantly among the esophageal control groups but was elevated 5-fold in BE, 8-fold in dysplasia and 16-fold in EAC compared to normal esophageal controls with no erosive GERD. Erosive GERD tissue had slightly higher median Cox-2 expression but Cox-2 expression in normal antrum was much higher than that in a normal esophagus, close to that of dysplasia. In contrast to that of Cox-2, Cox-1 expression was significantly decreased in all neoplastic tissues compared to normal controls. Cox-1 and Cox-2 expression varied over a wide range in the neoplastic tissues but over a relatively narrow range in the esophageal normal tissues. The occurrence of substantial alterations in Cox-1 and Cox-2 expression at the BE stage indicates that these are early events in the development of EAC. These results confirm the important role of Cox-2 amplification in the pathogenesis of esophageal adenocarcinoma, but the unexpected down-regulation of Cox-1 raises questions about its role in carcinogenesis.

Quantitative determination of p16 gene expression by RT-PCR.

In recent years, gene expression quantitation of tumor cells has become of principal importance to analyze gene patterns responsible for cancer development, progression, and resistance to treatment. Whereas semi-quantitative methods, such as Northern blotting analysis, allow only a dichotomous differentiation between positive and negative gene expressions, the real-time quantitative polymerase chain reaction (qRT-PCR) combines a large range of results with an accurate and highly reproducible quantitation of genes. In addition to forward and reverse primers, as used in a conventional PCR, the qRT-PCR system utilizes a probe that is labeled with a fluorescent dye. The probe is an oligonucleotide, homologous to a DNA sequence between the two flanking PCR primers. Degradation of the probe by the activity of the Taq DNA polymerase generates a fluorescent signal that will be detected by means of a laser integrated in the sequence detector. This chapter will cover the isolation of total RNA from frozen tissue, the transcription of RNA to cDNA, and the analysis of the relative gene expression by qRT-PCR. Although in principle applicable to any gene of interest, we will use as an example the qRT-PCR analysis of p16INK4a, whose gene product is involved in cell cycle and senescence checkpoint control.

Multimodal fusion imaging ensemble for targeted sentinel lymph node management: initial results of an innovative promising approach for anatomically difficult lymphatic drainage in different tumour entities.

PURPOSE: There are situations where exact identification and localisation of sentinel lymph nodes (SLNs) are very difficult using lymphoscintigraphy, a hand-held gamma probe and vital dye, either a priori or a posteriori. We developed a new method using a simultaneous injection of two lymphotropic agents for exact topographical tomographic localisation and biopsy of draining SLNs. The purpose of this prospective pilot study was to investigate the feasibility and efficacy of this method ensemble. METHODS: Fourteen patients with different tumour entities were enrolled. A mixture of (99m)Tc-nanocolloid and a dissolved superparamagnetic iron oxide was injected interstitially. Dynamic, sequential static lymphoscintigraphy and SPECT served as pathfinders. MR imaging was performed 2 h after injection. SPECT, contrast MRI and, if necessary, CT scan data sets were fused and evaluated with special regard to the topographical location of SLNs. The day after injection, nine patients underwent SLN biopsy and, in the presence of SLN metastasis, an elective lymph node dissection. RESULTS: Twenty-five SLNs were localised in the 14 patients examined. A 100% fusion correlation was achieved in all patients. The anatomical sites of SLNs detected during surgery showed 100% agreement with those localised on the multimodal fusion images. SLNs could be excised in 11/14 patients, six of whom had nodal metastasis. CONCLUSION: Our novel approach of multimodal fusion imaging for targeted SLN management in primary tumours with lymphatic drainage to anatomically difficult regions enables SLN biopsy even in patients with lymphatic drainage to obscure regions. Currently, we are testing its validity in larger patient groups and other tumour entities.

Gene expression in tumor-adjacent normal tissue is associated with recurrence in patients with rectal cancer treated with adjuvant chemoradiation.

Recurrence is a significant clinical problem for patients with rectal cancer treated with adjuvant chemoradiation. Previous studies have suggested that determining intratumoral gene expression of key genes may be helpful in predicting clinical outcome of patients with gastrointestinal malignancies undergoing chemotherapy. The role of molecular predictors for prediction of recurrence in the setting of adjuvant chemoradiotherapy is not well established. The present study was designed to identify a genetic profile that would be associated with recurrence in patients with rectal cancer treated with adjuvant chemoradiation therapy. A retrospective study with a longitudinal cohort and a cross-sectional cohort of 67 patients with locally advanced rectal cancer who underwent cancer resection, followed by 5-fluorouracil (5-FU) plus pelvic radiation was conducted. Total RNA was extracted from formalin-fixed, paraffin-embedded, laser-captured-microdissected tissue. We determined mRNA levels of genes involved in the 5-FU pathway (thymidylate synthase, dihydropyrimidine dehydrogenase), DNA-repair (excision-repair cross-complementing factor 1, Rad51), angiogenesis/radiation sensitivity [vascular endothelial growth factor (VEGF)] and radio-sensitivity [epidermal growth factor receptor (EGFR)] in tumor tissue and tumor-adjacent normal tissue by quantitative reverse transcriptase-polymerase chain reaction. In univariate analysis, only intratumoral gene expression level of VEGF (P = 0.055) was associated with recurrence, whereas elevated mRNA expression levels of thymidylate synthase (P = 0.008), VEGF (P = 0.023) and EGFR (P = 0.004) in tumor-adjacent normal tissue were significantly associated with recurrence. Multivariate analysis using recursive partitioning indicated that distinct groups of recurrence could be defined by elevated mRNA expression levels of VEGF, EGFR in tumor-adjacent normal tissue, and Rad51 in tumor tissue. These data suggest that the genetic profile of the tumor-adjacent normal tissue may be associated with treatment failure, indicating that tumor microenvironment may be more important in the development of recurrence of rectal tumors than formerly expected.