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Objective This study aimed to assess psychological functioning, quality of life, and regret about screening after a positive fecal immunochemical test (FIT) and subsequent colonoscopy, and to evaluate changes over time. Methods This is a prospective cohort study. Individuals aged 55 to 75 with a positive FIT that were referred for colonoscopy between July 2017 and November 2018, were invited to complete questionnaires related to psychological distress and health‐related quality of life at three predefined time points: before colonoscopy, after histopathology result notification, and after 6 months. Four questionnaires were used: the Psychological Consequences Questionnaire (PCQ), the six‐item Cancer Worry Scale (CWS), the Decision Regret Scale (DRS), and the 36‐item Short‐Form (SF‐36). Results A total of 1066 participants out of 2151 eligible individuals were included. Patients with cancer showed a significant increase in psychological dysfunction (P = .01) and cancer worry (P = .008) after colonoscopy result notification, and a decline to pre‐colonoscopy measurements after 6 months. In the no‐cancer groups, psychological dysfunction and cancer worry significantly decreased over time (P 25). A good global quality of life was reported in participants with no cancer. Conclusion Some psychological distress remains up to 6 months after colonoscopy in participants who tested false‐positive in the Dutch bowel cancer screening program.

Significance: Colorectal cancer incidence has decreased largely due to detection and removal of polyps. Computer-aided diagnosis development may improve on polyp detection and discrimination. Aim: To advance detection and discrimination using currently available commercial colonoscopy systems, we developed a deep neural network (DNN) separating the color channels from images acquired under narrow-band imaging (NBI) and white-light endoscopy (WLE). Approach: Images of normal colon mucosa and polyps from colonoscopies were studied. Each color image was extracted based on the color channel: red/green/blue. A multilayer DNN was trained using one-channel, two-channel, and full-color images. The trained DNN was then tested for performance in detection of polyps. Results: The DNN performed better using full-colored NBI over WLE images in the detection of polyps. Furthermore, the DNN performed better using the two-channel red + green images when compared to full-color WLE images. Conclusions: The separation of color channels from full-color NBI and WLE images taken from commercially available colonoscopes may improve the ability of the DNN to detect and discriminate polyps. Further studies are needed to better determine the color channels and combination of channels to include and exclude in DNN development for clinical use.

α-Linolenic acid (ALA, 18:3n-3) and γ-gamma linolenic acid (GLA, 18:3n-6) are polyunsaturated fatty acids (PUFA) that improve the human health. The present study focused on testing the in vitro antitumor actions of pure ALA and GLA on the HT-29 human colorectal cancer cell line. Cell viability was checked by MTT ((3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test, cell membrane damage by the lactate dehydrogenase assay, apoptosis was tested by both caspase-3 activity trial and transmission electron microscopy images, and protein composition was analyzed by quantitative proteomics analysis. MTT test revealed IC50 values of 230 and 255 μM for ALA and GLA, respectively, at 72 h. After 24 h of incubation, both ALA and GLA induced apoptosis on HT-29 colorectal cancer cells according to the caspase-3 assay and microscopy images. SWATH/MS analysis evidenced that ALA significantly affected the mitochondrial protein import pathway and the citric acid cycle pathway, while GLA did not significantly affect any particular pathway. In summary, both ALA and GLA showed concentration-dependent inhibitory effects on HT-29 cells viability and induced cell death by apoptosis. ALA significantly affected cellular pathways, while GLA does not have specific actions on either pathway. Both n-3 and n-6 C18 PUFA are bioactive food components useful in the colorectal cancer prevention.

Significance: Many studies in colorectal cancer (CRC) use murine ectopic tumor models to determine response to treatment. However, these models do not replicate the tumor microenvironment of CRC. Physiological information of treatment response derived via diffuse reflectance spectroscopy (DRS) from murine primary CRC tumors provide a better understanding for the development of new drugs and dosing strategies in CRC. Aim: Tumor response to chemotherapy in a primary CRC model was quantified via DRS to extract total hemoglobin content (tHb), oxygen saturation (StO2), oxyhemoglobin, and deoxyhemoglobin in tissue. Approach: A multimodal DRS and imaging probe (0.78 mm outside diameter) was designed and validated to acquire diffuse spectra longitudinally—via endoscopic guidance—in developing colon tumors under 5-fluoruracil (5-FU) maximum-tolerated (MTD) and metronomic regimens. A filtering algorithm was developed to compensate for positional uncertainty in DRS measurements Results: A maximum increase in StO2 was observed in both MTD and metronomic chemotherapy-treated murine primary CRC tumors at week 4 of neoadjuvant chemotherapy, with 21 ± 6 % and 17 ± 6 % fold changes, respectively. No significant changes were observed in tHb. Conclusion: Our study demonstrates the feasibility of DRS to quantify response to treatment in primary CRC models.

OBJECTIVE: Even when medical treatments are limited, supporting patients' coping strategies could improve their quality of life. Greater understanding of patients' coping strategies, and influencing factors, can aid developing such support. We examined the prevalence of coping strategies and associated variables.METHODS: We used sociodemographic and baseline data from the ACTION trial, including measures of Denial, Acceptance, and Problem-focused coping (COPE; Brief COPE inventory), of patients with advanced cancer from six European countries. Clinicians provided clinical information. Linear mixed models with clustering at hospital level were used.RESULTS: Data from 675 patients with stage III/IV lung (342, 51%) or stage IV colorectal (333, 49%) cancer were used; mean age 66 (10 SD) years. Overall, patients scored low on Denial and high on Acceptance and Problem-focused coping. Older age was associated with higher scores on Denial than younger age (β = 0.05; CI[0.023; 0.074]), and patients from Italy (β = 1.57 CI[0.760; 2.388]) and Denmark (β = 1.82 CI[0.881; 2.750]) scored higher on Denial than patients in other countries.CONCLUSIONS: Patients with advanced cancer predominantly used Acceptance and Problem-focused coping, and Denial to a lesser extent. Since the studied coping strategies of patients with advanced cancer vary between subpopulations, we recommend taking these factors into account when developing tailored interventions to support patients' coping strategies.

Approximately 50% of all colorectal cancer (CRC) patients will develop metastasis to the liver. 90Y selective internal radiation therapy (SIRT) is an established treatment for metastatic CRC. There is still a fundamental lack of understanding regarding the radiobiology underlying the dose response. This study was designed to determine the radiosensitivity of two CRC cell lines (DLD-1 and HT-29) to 90Y β − radiation exposure, and thus the relative effectiveness of 90Y SIRT in relation to external beam radiotherapy (EBRT). A 90Y-source dish was sandwiched between culture dishes to irradiate DLD-1 or HT-29 cells for a period of 6 d. Cell survival was determined by clonogenic assay. Dose absorbed per 90Y disintegration was calculated using the PENELOPE Monte Carlo code. PENELOPE simulations were benchmarked against relative dose measurements using EBT3 GAFchromic™ film. Statistical regression based on the linear-quadratic model was used to determine the radiosensitivity parameters and using R. These results were compared to radiosensitivity parameters determined for 6 MV clinical x-rays and 137Cs γ-ray exposure. Equivalent dose of EBRT in 2 Gy ( ) and 10 Gy ( ) fractions were derived for 90Y dose. HT-29 cells were more radioresistant than DLD-1 for all treatment modalities. Radiosensitivity parameters determined for 6 MV x-rays and 137Cs γ-ray were equivalent for both cell lines. The ratio for 90Y β −-particle exposure was over an order of magnitude higher than the other two modalities due to protraction of dose delivery. Consequently, an 90Y SIRT absorbed dose of 60 Gy equates to an of 28.7 and 54.5 Gy and an of 17.6 and 19.3 Gy for DLD-1 and HT-29 cell lines, respectively. We derived radiosensitivity parameters for two CRC cell lines exposed to 90Y β −-particles, 6 MV x-rays, and 137Cs γ-ray irradiation. These radiobiological parameters are critical to understanding the dose response of CRC lesions and ultimately informs the efficacy of 90Y SIRT relative to other radiation therapy modalities.

ObjectiveChemotherapy‐induced sensory peripheral neuropathy (CIPN) is common among colorectal cancer (CRC) survivors. The aim of this study was to examine whether CIPN is associated with both psychological distress (ie, anxiety and depression) and fatigue and whether the relationship between CIPN and fatigue can (partly) be explained by psychological distress.MethodsAll CRC survivors diagnosed between 2000 and 2009 as registered by the population‐based Netherlands Cancer Registry (Eindhoven region) were eligible for participation. Chemotherapy‐treated survivors completed questions on CIPN (EORTC QLQ‐CIPN20), psychological distress (HADS), and fatigue (FAS) on average 5.6 years after diagnosis. Simple and multiple mediation analyses were performed to examine anxiety and depression as possible mediators in the association between CIPN and fatigue.ResultsSurvivors with high (ie, upper 30% of scores) CIPN (n = 172) reported more anxiety and depressive symptoms and more fatigue compared with those with low CIPN (n = 299). Furthermore, among survivors with high CIPN, those who were anxious, depressed, or both reported more fatigue compared with those without psychological distress. These differences were clinically relevant. Finally, mediation analyses showed that while CIPN was directly associated with fatigue, the relationship between CIPN and fatigue was also significantly mediated by both anxiety and depression.ConclusionsCRC survivors with high CIPN report more fatigue, especially those who are also anxious and/or depressed. More research is needed on the direction of the relationship between CIPN, psychological distress, and fatigue. For now, the treatment of fatigue should also focus on addressing psychological distress, as treating fatigue alone might not be sufficient.

Colonoscopy is routinely performed for colorectal cancer screening but lacks the capability to accurately characterize precursor lesions and early cancers. High-resolution microendoscopy (HRME) is a low-cost imaging tool to visualize colorectal polyps with subcellular resolution. We present a computer-aided algorithm to evaluate HRME images of colorectal polyps and classify neoplastic from benign lesions. Using histopathology as the gold standard, clinically relevant features based on luminal morphology and texture are quantified to build the classification algorithm. We demonstrate that adenomatous polyps can be identified with a sensitivity and specificity of 100% and 80% using a two-feature linear discriminant model in a pilot test set. The classification algorithm presented here offers an objective framework to detect adenomatous lesions in the colon with high accuracy and can potentially improve real-time assessment of colorectal polyps.

Objective: More people are living with the consequences of cancer and comorbidity. We describe frequencies of comorbidities in a colorectal cancer cohort and associations with health and well‐being outcomes up to 5 years following surgery.Methods: Prospective cohort study of 872 colorectal cancer patients recruited 2010 to 2012 from 29 UK centres, awaiting curative intent surgery. Questionnaires administered at baseline (pre‐surgery), 3, 9, 15, 24 months, and annually up to 5 years. Comorbidities (and whether they limit activities) were self‐reported by participants from 3 months. The EORTC QLQ‐C30 and QLQ‐CR29 assessed global health/quality of life (QoL), symptoms, and functioning. Longitudinal analyses investigated associations between comorbidities and health and well‐being outcomes.Results: At baseline, the mean age of participants was 68 years, with 60% male and 65% colon cancer. Thirty‐two per cent had 1 and 40% had ≥2 comorbidities. The most common comorbidities were high blood pressure (43%), arthritis/rheumatism (32%), and anxiety/depression (18%). Of those with comorbidities, 37% reported at least 1 that limited their daily activities. Reporting any limiting comorbidities was associated with poorer global health/QoL, worse symptoms, and poorer functioning on all domains over 5‐year follow‐up. Controlling for the most common individual comorbidities, depression/anxiety had the greatest deleterious effect on outcomes.Conclusions: Clinical assessment should prioritise patient‐reported comorbidities and whether these comorbidities limit daily activities, as important determinants of recovery of QoL, symptoms, and functioning following colorectal cancer. Targeted interventions and support services, including multiprofessional management and tailored assessment and follow‐up, may aid recovery of health and well‐being in these individuals.

Most solid cancers are treated by surgical resections to reduce the burden of disease. Surgeons often face the challenge of detecting small areas of residual neoplasm after resection or finding small primary tumors for the initial resection. Intraoperative molecular imaging (IMI) is an emerging technology with the potential to dramatically improve cancer surgery operations by allowing surgeons to better visualize areas of neoplasm using fluorescence imaging. Over the last two years, two molecular optical contrast agents received U.S. Food and Drug Administration approval, and several more drugs are now on the horizon. Thus a conference was organized at the University of Pennsylvania to bring together oncologic surgeons from different specialties to discuss the current clinical status of IMI trials with a specific focus on phase 2 and phase 3 studies. In addition, phase 1 and experimental trials were also discussed briefly, to highlight other novel techniques. Our review summarizes the discussions from the conference and delves into the types of cancers discussed, different contrast agents in human trials, and the clinical value being studied. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License.

pColorectal cancer is the second most common malignancy diagnosed globally. Critical gaps exist in diagnostic and surveillance imaging modalities for colorectal neoplasia. Although prior studies have demonstrated the capability of photoacoustic imaging techniques to differentiate normal from neoplastic tissue in the gastrointestinal tract, evaluation of deep tissue with a fast speed and a large field of view remains limited. To investigate the ability of photoacoustic technology to image deeper tissue, we conducted a pilot study using a real-time co-registered photoacoustic tomography (PAT) and ultrasound (US) system. A total of 23italicex vivo/italichuman colorectal tissue samples were imaged immediately after surgical resection. Co-registered photoacoustic images of malignancies showed significantly increased PAT signal compared to normal regions of the same sample. The quantitative relative total hemoglobin (rHbT) concentration computed from four optical wavelengths, the spectral features, such as the mean spectral slope, and 0.5-MHz intercept extracted from PAT and US spectral data, and image features, such as the first- and second-order statistics along with the standard deviation of the mean radon transform of PAT images, have shown statistical significance between untreated colorectal tumors and the normal tissue. Using either a logistic regression model or a support vector machine, the best set of parameters of rHbT and PAT intercept has achieved area-under-the-curve (AUC) values of 0.97 and 0.95 for both training and testing data sets, respectively, for prediction of histologically confirmed invasive carcinoma./p.

In the last decades, laparoscopic surgery has become the gold standard in patients with colorectal cancer. To overcome the drawback of reduced tactile feedback, real-time tissue classification could be of great benefit. In this ex vivo study, hyperspectral imaging (HSI) was used to distinguish tumor tissue from healthy surrounding tissue. A sample of fat, healthy colorectal wall, and tumor tissue was collected per patient and imaged using two hyperspectral cameras, covering the wavelength range from 400 to 1700 nm. The data were randomly divided into a training (75%) and test (25%) set. After feature reduction, a quadratic classifier and support vector machine were used to distinguish the three tissue types. Tissue samples of 32 patients were imaged using both hyperspectral cameras. The accuracy to distinguish the three tissue types using both hyperspectral cameras was 0.88 (STD=0.13) on the test dataset. When the accuracy was determined per patient, a mean accuracy of 0.93 (STD=0.12) was obtained on the test dataset. This study shows the potential of using HSI in colorectal cancer surgery for fast tissue classification, which could improve clinical outcome. Future research should be focused on imaging entire colon/rectum specimen and the translation of the technique to an intraoperative setting.

BACKGROUND Molecular characterization of circulating tumor cells (CTCs) holds great promise for monitoring metastatic progression and characterizing metastatic disease. However, leukocyte and red blood cell contamination of routinely isolated CTCs makes CTC-specific molecular characterization extremely challenging. METHODS Here we report the use of a paper-based medium for efficient extraction of microRNAs (miRNAs) from limited amounts of biological samples such as rare CTCs harvested from cancer patient blood. Specifically, we devised a workflow involving the use of Flinders Technology Associates (FTA)® Elute Card with a digital PCR-inspired “partitioning” method to extract and purify miRNAs from plasma and CTCs. RESULTS We demonstrated the sensitivity of this method to detect miRNA expression from as few as 3 cancer cells spiked into human blood. Using this method, background miRNA expression was excluded from contaminating blood cells, and CTC-specific miRNA expression profiles were derived from breast and colorectal cancer patients. Plasma separated out during purification of CTCs could likewise be processed using the same paper-based method for miRNA detection, thereby maximizing the amount of patient-specific information that can be derived from a single blood draw. CONCLUSIONS Overall, this paper-based extraction method enables an efficient, cost-effective workflow for maximized recovery of small RNAs from limited biological samples for downstream molecular analyses.

In the past few years, optical magnification endoscopy and chromoscopy have gained renewed interest in the West as a means for the early detection of minute lesions in patients with Barrett's oesophagus and in patients referred for colonic cancer screening. In Barrett's oesophagus, the vast majority of data on the use of chromoscopy deals with the application of methylene blue. Conventional videoendoscopy in combination with methylene blue staining improves the detection of Barrett's mucosa. A correlation has been shown between variation and intensity of staining and histologically verified stages of dysplasia or cancer. Magnification endoscopy and chromoscopy improve the detection of colonic non-polypoid lesions associated with neoplasia and carcinoma. Pitt pattern analysis enables the distinction of non-neoplastic non-polypoid lesions (type I and II) from neoplastic type non-polypoid lesions (type III-V) with great accuracy. It is certain that "old fashioned" chromoscopy combined with advanced endoscopic technology carry a great diagnostic potential and should be further put to the test for use in daily clinical practice.

The three autosomal dominant inherited polyposis syndromes, familial adenomatous polyposis, juvenile polyposis, and Peutz-Jeghers polyposis predispose to colorectal cancer as does hereditary non-polyposis colorectal cancer syndrome. Uncovering the genetic background of these four cancer traits provides the possibility for genetic testing of the family members of an affected patient. Before testing identification of the underlying family specific pathogenic mutation is mandatory. This is possible in about 60% to 95% of families. Endoscopic surveillance can be safely discontinued in mutation negative family members and surveillance or prophylactic surgery can be targeted to mutation positive members alone. Testing requires genetic counselling and written informed consent to prevent misunderstanding and to minimise untoward effects such as anxiety. Permanent surveillance and adequate prophylactic treatment for all mutation positive subjects and families is best ensured in national or regional polyposis registries with the capacity to take care of long term follow up from generation to generation.

Introduction In 2000–2004 there were, on average, 93 8 new cases of colorectal cancer (CRC) diagnosed per annum in Northern Ireland, accounting for 13.9% of all cancers. The two week “red flag” referral system aims to detect 90% of patients with CRC for prompt treatment. The aim of this study is to examine the impact of the “red flag” referral system on identification of patients with CRC, time to treatment and stage of disease. Methods A random sample of 200 patients referred via the “red flag” system was identified from the local cancer patient tracker database. Data pertaining to demographics, time to hospital appointment, appropriateness of referral and diagnosis were collected. For patients identified with CRC, the stage of disease and time to first definitive treatment were also documented. Results Of the 200 patients, 56% were female. The age range was 27–93 years. Eighty three percent were seen within 14 days of referral. Referrals adhered to the guidelines in 45% of cases. There were 4 pancreatic cancers, 1 endometrial cancer, 1 ovarian cancer and 1 myelodysplasia diagnosed. Three patients were diagnosed with CRC (1.5%). Of these, 1 was palliative and the remaining 2 commenced definitive management within 6 days of decision to treat. Conclusion The “red flag” referral system does not appear to be effective in identifying patients with CRC but did identify patients with other types of cancer. Less than half of the referrals adhered to the guidelines. A review of this system should be undertaken.

Aims/Background—The aim of this study was to identify p53 and K-ras gene mutations in carcinoma of the rectum among Finnish women. Mutation patterns might give clues to aetiological factors when comparisons are made with other human tumours. Methods—Of 134 women with carcinoma of the rectum, paraffin wax embedded specimens of the tumour tissue were obtained from 118 patients. Genomic DNA was extracted, and exons 4–8 of the p53 gene and codons 12/13 and 61 of the K-ras gene were amplified, and analysed for mutations by single strand conformation polymorphism and direct sequencing. The production of p53 and K-ras proteins was studied by immunohistochemistry. Results—The overall crude frequency for mutations in the p53 gene was 35% but the true frequency appears to be higher (up to 56%). In the K-ras gene, the mutation frequency (15%) was significantly lower than that reported for colon cancer. In the p53 gene, the mutation frequency increased significantly with patient age. In a high proportion of patients (14%) the rectal tumours contained small subclones of tumour cells that displayed extremely rare mutations at codons 110 and 232 of the p53 gene. Hot spot codon 175 mutations were significantly less common in rectal cancer than in cancer of the colon. Conclusions—Rectal cancer among Finnish women has characteristics in the mutations of the p53 and K-ras genes that are uncommon in other human tumours, including cancer of the colon. A biological explanation of these findings is not clear at present, but might be associated with an unidentified genetic factor in Finland.

Objective: Colorectal cancer (CRC) is the third most common type of cancer with resulting major mortality. In a bid to reduce the mortality, bowel cancer screening has been established in the United Kingdom. The screening programme was commenced in Northern Ireland in 2010 within the Northern Health and Social Care Trust, following its implementation in England and Scotland. This study aimed to look at early outcome data for bowel cancer screening in Northern Ireland and compare data with other regions in the UK. Design: A retrospective analysis was conducted of patients who tested faecal occult blood (FOB) positive and attended for pre-assessment between May 2010 and May 2011. Data was also collected from the computerised endoscopy database (Endoscribe®). Patient demographics, colonoscopic depth of insertion, findings and complications were documented. Subsequent surgical management, pathological staging and final outcome were also noted. Results: 182 patients attended for pre-assessment in the time frame and 178 patients proceeded to colonoscopy. The commonest pathology encountered was polyps, identified in 95 (52.7%) patients. Macroscopically 13 cancers were seen on endoscopy and a further two were found on post-operative histology of polyps that were not amenable to endoscopic resection. In addition, 5 malignant polyps were found on histological analysis of the excised polyps. The staging of cancers was favourable with 35% being Dukes’ A stage. Conclusion: Outcomes from the first year of colorectal cancer screening in the Northern Trust are in keeping with early results from previous studies in terms of cancer detection rates per colonoscopy and proportion of early stage cancers. However, the adenoma detection rate was higher than anticipated.

Objectives Carcinogenic action of meat-related exposures, such as heterocyclic amines (HCAs), polycyclic aromatic hydrocarbons (PAHs), and N-nitroso compounds (NOCs), might explain positive associations between red and processed meat and colorectal neoplasia. Single nucleotide polymorphisms in xenobiotic metabolizing enzyme (XME) genes could alter activation/detoxfication of these compounds. Methods We evaluated interactions between several XME genes (CYP1A1, CYP1B1, CYP2A6, CYP2C9, CYP2E1, CYP3A4, EPHX1, GSTM1, GSTM2, GSTT1, NAT1, NAT2, NQO1, SULT1A1, and SULT1A2) and meat-related exposures using a pathway-based approach in 720 advanced colorectal adenoma cases of the distal colon or rectum and 746 controls from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Using meat-related databases, we estimated intake of the HCAs, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-amino-1-methyl-6-phenyl-imidazo[4,5-b]pyridine (PhIP), the PAH, benzo[a]pyrene (B[a]P), and nitrate/nitrite, as NOC precursors. Results There were possible interactions between PhIP and CYP1B1 (Pinteraction=0.019) and NQO1 (Pinteraction=0.007), B[a]P and CYP1B1 (Pinteraction=0.005) and CYP3A4 (Pinteraction=0.021), and nitrate/nitrite and CYP1A1 (Pinteraction=0.022) in relation to colorectal adenoma. However, none of these interactions were statistically significant using a false discovery rate threshold of 0.20. Conclusions Common variants in XME genes may modify the association of HCAs, PAHs, and nitrate/nitrite with advanced colorectal adenoma, but investigation in other populations is required, especially within consortia.

Gastroscopy, small bowel endoscopy, and colonoscopy are uncomfortable because they require comparatively large diameter flexible cables to be pushed into the bowel, which carry light by fibreoptic bundles, power, and video signals. Small bowel endoscopy is currently especially limited by problems of discomfort and failure to advance enteroscopes far into the small bowel. There is a clinical need for better methods to examine the small bowel especially in patients with recurrent gastrointestinal bleeding from this site.

Aims—Laser capture microdissection is a recent development that enables the isolation of specific cell types for subsequent molecular analysis. This study describes a method for obtaining proteome information from laser capture microdissected tissue using colon cancer as a model. Methods—Laser capture microdissection was performed on toluidine blue stained frozen sections of colon cancer. Tumour cells were selectively microdissected. Conditions were established for solubilising proteins from laser microdissected samples and these proteins were separated by two dimensional gel electrophoresis. Individual protein spots were cut from the gel, characterised by mass spectrometry, and identified by database searching. These results were compared with protein expression patterns and mass spectroscopic data obtained from bulk tumour samples run in parallel. Results—Proteins could be recovered from laser capture microdissected tissue in a form suitable for two dimensional gel electrophoresis. The solubilised proteins retained their expected electrophoretic mobility in two dimensional gels as compared with bulk samples, and mass spectrometric analysis was also unaffected. Conclusion—A method for performing two dimensional gel electrophoresis and mass spectrometry using laser capture microdissected tissue has been developed.

Objectives A study was conducted to investigate cancer risks in a cohort of pulp and paper workers. Methods All male workers with at least 1 year of employment in 14 pulp and paper mills in 1950-1992 were studied. Standardized incidence ratios (SIR) were used to compare the cancer incidence of the cohort with that of the Canadian male population. Record linkage with the National Cancer Registry was performed using the generalized iterative record linkage method. Results Altogether 1756 cancer cases were observed in the entire cohort. For 15 years of work or more, the entire cohort had significantly increased SIR values for pleural and prostate cancer and skin melanoma; there was also a significantly increased risk for skin melanoma among workers in the kraft process only, rectal cancer among workers in the sulfite process only, and stomach and prostate cancer and all leukemias combined among workers in both the kraft and sulfite processes. A separate analysis comparing workers in pulping and papermaking with those in the pulping process only did not reveal any difference in cancer risk and hence did not modify the results. The SIR values for skin melanoma were not significantly increased in a comparison using the British Columbia male population. Nine of 10 pleural cancers were mesotheliomas, which likely reflect past asbestos exposure. Conclusions The results suggest that long-term work in the pulp and paper industry is associated with excess risks of prostate and stomach cancers and all leukemias for work in both kraft and sulfite processes and of rectal cancer for work in the sulfite process only.