Solveig Norheim Andersen

Growth of colorectal polyps: redetection and evaluation of unresected polyps for a period of three years.

BACKGROUND, AIMS, AND PATIENTS: In a prospective follow up and intervention study of colorectal polyps, leaving all polyps less than 10 mm in situ for three years, analysis of redetection rate, growth, and new polyp formation was carried out in 116 patients undergoing annual colonoscopy. The findings in relation to growth and new polyp formation were applied to 58 subjects who received placebo. RESULTS: Redetection rate varied from 75-90% for each year, and was highest in the rectum and sigmoid colon. There was no net change in size of all polyps in the placebo group, however, polyps less than 5 mm showed a tendency to net growth, and polyps 5-9 mm a tendency to net regression in size, both for adenomas and hyperplastic polyps. This pattern was verified by computerised image analysis. Patients between 50 and 60 years showed evidence of adenoma size increase compared with the older patients, and the same was true for those with multiple adenomas (four to five) compared with those with a single adenoma. The new adenomas were significantly smaller and 71% were located in the right side of the colon. Patients with multiple adenomas had more new polyps at all the follow up examinations than patients with a single adenoma. One patient developed an invasive colorectal carcinoma, which may be evolved from a previously overlooked polyp. Two polyps, showing intramucosal carcinoma after follow up for three years, were completely removed, as judged by endoscopy and histological examination. CONCLUSIONS: The results show that follow up of unresected colorectal polyps up to 9 mm is safe. The consistency of growth retardation of medium sized polyps suggests extended intervals between the endoscopic follow up examinations, but the increased number of new polyps in the proximal colon indicates total colonoscopy as the examination of choice. The growth retardation of the medium sized polyps may partly explain the discrepancy between the prevalence of polyps and the incidence of colorectal cancer.

Growth and recurrence of colorectal polyps: a double-blind 3-year intervention with calcium and antioxidants.

Background: Dietary calcium and antioxidants have been suggested as protective agents against colorectal cancer. This has been supported by animal experimental studies, case control and cohort studies. Materials and Methods: In a prospective intervention study of colorectal adenomas, and intermediary stage in colorectal carcinogenesis, 116 polyp-bearing patients received a placebo-controlled daily mixture of β-carotene 15 mg, vitamin C 150 mg, vitamin E 75 mg, selenium 101 µg, and calcium (1.6 g daily) as carbonate for a period of 3 years with annual colonoscopic follow-up to test if the mixture was able to reduce polyp growth or recurrence. All polyps of <10 mm at enrolment or follow-up were left unresected until the end of the study. Results: 87–91% of the patients attended the annual endoscopic follow-up investigations, and 19% of the patients dropped out of the medical intervention. The rest consumed 85% of the total amount of tablets over the 3 years. The fecal calcium concentration was 2.3–2.7 times higher in patients taking active medication compared to the placebo group. Diet registration showed that, when adding the intake of antioxidants and calcium from diet and intervention, there was a significant difference between the intake of these substances in the active and the placebo group. No difference was detected in the growth of adenomas between the active and the placebo group from year to year and for the total study period. Moreover, there was no effect on polyps of <5 or 5–9 mm, or on polyps in the different colonic segments analyzed separately. A reduced growth of adenomas was found in patients <60 years of age taking active medication (n = 8) compared to those taking placebo (n = 6; mean difference 2.3 mm; 95% CI 0.26–4.36). There was a significantly lower number of patients free of new adenomas in the placebo group compared to those taking active medication as tested by logistic regression and Kaplan-Meier analysis (log-rank test p value 0.035). Subgroup analysis showed that only the group of patients with no family history of colorectal cancer, those with only one adenoma at inclusion, and those <65 years benefitted from the intervention medication. Conclusion: The study did not find an overall effect on polyp growth. Our data, however, may support a protective role of calcium and antioxidants on new adenoma formation.

Hypoxic/ischaemic brain damage, especially pallidal lesions, in heroin addicts.

The occurrence of pallidal lesions with or without other hypoxic/ischaemic brain injuries was evaluated in 100 intravenous (i.v.) heroin addicts. The brains were collected consecutively from forensic autopsies during the period from January 1995 to June 1996. The autopsies were required by the police and performed at The Institute of Forensic Medicine, The National Hospital, Oslo. There were 21 women and 79 men, median age 32 (range 21-47) and 34 (19-60) years, respectively. Of 38 brains with abnormalities, twenty-five cases showed isolated or combined lesions of hypoxic/ischaemic origin. Pallidal lesions were found in nine brains; six lesions were old, one was subacute (a couple of weeks), and two were part of recent, generalized hypoxia/ischaemia. Six persons had old infarcts in the hippocampal formation, and one of them in combination with old pallidal infarcts. In seven brains small and old infarcts were found in watershed areas in the cerebellum. Between five and ten percent of i.v. heroin addicts might have pallidal infarcts, either as the sole lesion, or combined with other manifestations of hypoxic/ischaemic brain injury. This might give severe mental disturbances in the affected persons.

Stereospecific determination of citalopram and desmethylcitalopram by capillary electrophoresis and liquid-phase microextraction.

A chiral capillary electrophoresis (CE) system allowing simultaneous enantiomer determination of citalopram (CIT) and its pharmacologically active metabolite desmethylcitalopram (DCIT) was developed. Excellent chiral separation was obtained using 1% sulfated-beta-cyclodextrin (S-beta-CD) as chiral selector in combination with 12% ACN in 25 mM phosphate pH 2.5. Samples were prepared by liquid-phase microextraction (LPME) based on a rodlike porous polypropylene hollow fibre. CIT and DCIT were extracted from 1 ml plasma made alkaline with NaOH, into dodecyl acetate impregnated in the pores of a hollow fibre, and into 20 mM phosphate pH 2.75, inside the hollow fibre. The acceptor solution was directly compatible with the CE system. Efficient sample clean-up was seen, and the recoveries were 46 and 29% for the enantiomers of CIT and DCIT, respectively, corresponding to 31 and 19 times enrichment. The limit of quantification (S/N=10) was <11.2 ng/ml, intra-day precision was <12.8% RSD, and inter-day precision was <14.5% RSD, for all enantiomers. The validated method was successfully applied to simultaneous determination of enantiomer concentrations of CIT and DCIT in plasma samples from nine patients treated with racemic citalopram. The results confirm LPME-CE as a suitable and promising tool for enantiomeric determination of chiral drugs and metabolites in biological matrices.

Liquid-phase microextraction combined with capillary electrophoresis, a promising tool for the determination of chiral drugs in biological matrices.

A disposable device for liquid-phase microextraction (LPME) based on porous polypropylene hollow fibres has recently been introduced. In the present paper, LPME was combined with capillary electrophoresis (CE) and the combination was for the first time evaluated for chiral determination of drugs in biological matrices. The chiral antidepressant drug mianserin was selected as model compound. The mianserin enantiomers were extracted from 0.5 ml of plasma added internal standard and made alkaline with 0.25 ml of 2 M NaOH. The unionised analytes were extracted into di-n-hexyl ether impregnated in the pores of the hollow fibre, and into an acidic solution inside the hollow fibre. This resulted in a three-phase system where the extracts were aqueous, and hence directly compatible with the CE system. Efficient sample clean-up was seen and the extraction recovery was 80% for both enantiomers. Discrimination between the enantiomers in the extraction system was not observed. The limit of quantitation (S/N= 10; 12.5 ng/ml for both enantiomers) and the limit of detection (S/N=3; 4 ng/ml for both enantiomers) were below the therapeutic range for mianserin. The method was validated and successfully applied to determine R- and S-mianserin in plasma samples from seven patients treated with mianserin, indicating that LPME-CE is a promising combination for analysis of racemic drugs present in low concentrations in biological matrices.

Relationship between clinical parameters and the colitis-colorectal cancer interval in a cohort of patients with colorectal cancer in inflammatory bowel disease.

Objective. Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (CRC), but more knowledge is needed about the possible relationship between clinical parameters and the time to development of cancer in IBD. The aim of the study was to determine the variability of the colitis-CRC interval and to analyze the association with clinical variables in an attempt to gain information on predictive factors of time to cancer within a relatively large cohort of CRC patients. Material and methods. Patients diagnosed with IBD prior to 1 May 2005 at three university hospitals in Oslo were matched against the CRC files at the Cancer Registry of Norway. Only histological re-confirmed IBD and adenocarcinoma of the colorectum were included. Results. Sixty-one patients with CRC in ulcerative colitis and 6 in Crohns disease, including 13 CRC in primary sclerosing cholangitis (PSC), covering a follow-up of 1625 patient years, were identified. The median time from diagnosis of IBD to CRC was 17 years. Seven of 58 patients (12%) developed CRC within 10 years from onset of IBD symptoms and 14/67 (21%) within 10 years after the diagnosis of IBD. The colitis-CRC interval decreased by a factor of 0.154 (p=0.018) when age at onset of IBD increased by one year. Mean age at onset of IBD was 30 years in patients with Dukes’ stage C or D compared with 20 years in Dukes’ stage A or B patients (p=0.017). The colitis-CRC interval decreased by a factor of 0.138 (p=0.003) when the percentage of the colitis-CRC interval with active symptoms increased by 1%. Patients with PSC were significantly younger at onset of IBD symptoms (+PSC: 19 years versus no PSC:29 years, p=0.04), but the colitis-CRC interval was similar to IBD without PSC (17 years versus 20 years, p=0.236). Mean duration of the colitis-CRC interval was not related to family history or drug consumption prior to CRC. Conclusions. In the present cohort, for whom the median time from diagnosis of IBD to CRC was 17 years, 21% of the cancers developed before 10 years of disease, which is before colonoscopic screening is usually recommended. High age at onset of IBD may be related to a more aggressive development of CRC in IBD and early inclusion in screening programs might be considered for this group of patients. Symptom activity but not the diagnosis of PSC, family history of CRC or IBD or drug treatment seems to have an effect on the colitis-CRC interval.

Lymph node micrometastases and isolated tumor cells influence survival in stage I and II colon cancer

PURPOSE: Lymph-node status is considered the most important prognostic factor in colorectal cancer. The aim of the present prospective study was to evaluate the influence of micrometastases and isolated tumor cells on recurrence and disease-free survival in colon cancer. METHODS: A total of 193 patients with colon cancer, operated on between 2000 and 2005, were enrolled in the study. All lymph nodes were examined by routine microscopy in hematoxylin and eosin-stained sections. If no metastases were identified in any node, all nodes were examined immunohistochemically with monoclonal antibody CAM 5.2. RESULTS: Ordinary metastases were found in 67 patients, leaving 126 patients in stage I/II. Immunohistochemistry showed that 5% (6/126) of these had micrometastases and 26% (33/126) had isolated tumor cells. A median of 5 years of follow-up revealed local or distant recurrence in 23% (9/39) of stage I/II patients with micrometastases or isolated tumor cells, compared with 7% (6/87) without micrometastases or isolated tumor cells (P = .010). Five-year disease-free survival for patients with and without micrometastases or isolated tumor cells was 75% and 93%, respectively (P = .012). When analyzed separately, patients with isolated tumor cells (excluding micrometastases) had also lower survival than node-negative patients (P = .012). CONCLUSION: The presence of micrometastases and isolated tumor cells was found to be a prognostic factor for recurrence and disease-free survival. This may have implications for future treatment of stage I/II colon cancer.

Total mesorectal excision for rectal cancer : Difference in outcome for low and high rectal cancer

PURPOSEThis prospective study was designed to assess the outcome through the first five years after the introduction of total mesorectal excision in 1993 in a Norwegian central hospital, with special regard to the difference between low (≤6 cm from anal verge) and high (>6 cm) rectal cancers.METHODSA total of 140 patients (81 males; median age, 64 (range, 29–87) years) underwent surgery for rectal cancer under curative intention.RESULTSLocal recurrence rates were 8 of 44 (18 percent) for the low cancers and 5 of 96 (5 percent) for the high, a statistically significant difference (P = 0.0014). Corresponding numbers when the R1 resections are excluded were 5 of 36 (13 percent) for the low and 4 of 92 (4 percent) for the high cancers (P = 0.002). The five-year survival after R0 resections of cancers <6 cm was significantly reduced compared with those >6 cm. The five-year overall survival for the whole material was 72 percent.CONCLUSIONSSurgery alone for rectal cancer can achieve overall good results, with five-year overall survival of 72 percent. The prognosis of the cancers of the lower rectum seems to be inherently different from the tumors of the higher level, both concerning local recurrence and five-year survival, suggesting different biologic behavior of the two cancers.

Villous, hypermucinous mucosa in long standing ulcerative colitis shows high frequency of K-ras mutations.

BACKGROUND K-rasmutation is one of the first genetic alterations in classical colorectal carcinogenesis. AIMS To investigate the role of K-ras mutations in carcinogenesis, in long standing ulcerative colitis. METHODS A total of 161 microdissected and 100 DNA samples from 13 patients were analysed for K-ras codons 12 and 13 mutations by means of a combination of enriched polymerase chain reaction amplification and temporal temperature gradient electrophoresis. RESULTS K-rasmutations were found in 21/161 (13%) microdissected samples in 7/13 large bowels (16 and five in codons 12 and 13, respectively), and in 10/100 (10%) mucosal DNA samples (six and four, respectively). One of four patients with six adenocarcinomas had a K-ras mutation in a carcinoma, as well as one of two patients with large dysplasia associated lesion or mass (DALM). Eight of 13 (61%) areas with villous architecture and large, distended goblet cells, had a K-rasmutation, which was significantly more frequent than in low grade dysplasia (one of 23, 4%) but did not reach significance versus high grade dysplasia (four of 14, 28.5%). K-rasmutations were found in one of 20 (5%) flat lesions indefinite for dysplasia, two of 14 (14%) in non-villous, hypermucinous mucosa, and in one of 57 flat areas negative for dysplasia. CONCLUSION The highest K-ras mutation frequency was found in villous, hypermucinous mucosa. We suggest that this entity should be investigated further as a potential risk lesion for cancer development. It may represent a pathway directly from non-classical dysplasia to cancer, not previously described.

Evaluation of suitable reference genes for normalization of real-time reverse transcription PCR analysis in colon cancer

BackgroundReal-time reverse transcription PCR (qRT-PCR) is frequently used for gene expression quantification due to its methodological reproducibility and sensitivity. The gene expression is quantified by normalization to one or more reference genes which are presumed stably expressed throughout a given experiment. The aim of this study was to validate a standardized experimental setup to identifying reference genes for normalization of qRT-PCR in the metastatic and non-metastatic colon cancer.MethodsIn this study, expression of 16 commonly used reference genes was quantified in tumour tissue and individual-matched normal mucosa in 18 non-metastatic colon cancer patients and 20 colon cancer patients with distant metastases using TaqMan Low Density Array (TLDA). The expression stability was determined and compared by means of geNorm and NormFinder.ResultsTwo pairs of genes, HPRT1/PPIA and IPO8/PPIA, were identified to be suitable to normalize gene expression data in metastatic and non-metastatic colon cancer patients, according to geNorm and NormFinder respectively.ConclusionWe propose a standardized approach of finding the most suitable reference gene(s) in every qRT-PCR experiment using TLDA.