Tumor Budding Versus Mismatch Repair Status in Colorectal Cancer - An Exploratory Analysis.

BACKGROUND: Tumor budding and a proficient mismatch repair (pMMR) status are considered adverse prognostic factors in colorectal cancer (CRC). The aim of this pilot study was to assess tumor budding in primary CRC with pMMR versus that with deficient mismatch repair (dMMR). MATERIALS AND METHODS: Tumor budding was retrospectively examined in the tumor from 134 patients with stage II and stage III CRC with known MMR status. The 29 available dMMR cases who developed recurrence or distant metastases (met+) were matched with a dMMR group with no recurrence or metastases (met-), and the pMMR/met+ group with pMMR/met- cases. RESULTS: Using tumor budding cut-offs of 5 and 10, a significantly higher percentage of high-grade tumor budding (≥5 and ≥10) was only found in the dMMR/met+ compared to pMMR/met+ subgroup (p=0.01 and p=0.02, respectively). CONCLUSION: A significantly higher grade of tumor budding was observed in the dMMR/met+ group, suggesting that tumor budding can provide prognostic information for patients with a dMMR status.

AmotL2 disrupts apical-basal cell polarity and promotes tumour invasion.

The establishment and maintenance of apical-basal cell polarity is essential for the functionality of glandular epithelia. Cell polarity is often lost in advanced tumours correlating with acquisition of invasive and malignant properties. Despite extensive knowledge regarding the formation and maintenance of polarity, the mechanisms that deregulate polarity in metastasizing cells remain to be fully characterized. Here we show that AmotL2 expression correlates with loss of tissue architecture in tumours from human breast and colon cancer patients. We further show that hypoxic stress results in activation of c-Fos-dependent expression of AmotL2 leading to loss of polarity. c-Fos/hypoxia-induced p60 AmotL2 interacts with the Crb3 and Par3 polarity complexes retaining them in large vesicles and preventing them from reaching the apical membrane. The resulting loss of polarity potentiates the response to invasive cues in vitro and in vivo in mice. These data provide a molecular mechanism how hypoxic stress deregulates cell polarity during tumour progression.

A randomized trial of transanal hemorrhoidal dearterialization with anopexy compared with open hemorrhoidectomy in the treatment of hemorrhoids.

BACKGROUND: Doppler guidance in hemorrhoidal surgery has become more frequent during the past decade. The method is mainly studied in nonrandomized trials. Data from randomized controlled trials are lacking. OBJECTIVE: The aim of this study was to compare early and midterm results of transanal hemorrhoidal dearterialization with anopexy to open hemorrhoidectomy. DESIGN, SETTINGS, PATIENTS, AND INTERVENTIONS: Forty patients with grade 2 to 3 hemorrhoids were randomly assigned to transanal hemorrhoidal dearterialization with anopexy (group A, n = 20) or open hemorrhoidectomy (group B, n = 20). A diary was used during the first 2 postoperative weeks. A self-reported symptom questionnaire was answered, and a clinical examination was performed preoperatively, after 2 to 4 months, and after 1 year. MAIN OUTCOME MEASURE: The main outcome measure was postoperative pain. RESULTS: Postoperative peak pain was lower in group A during the first week than in group B (p < 0.05), whereas no difference in overall pain was noted. More patients expressed normal well-being in group A (p = 0.045). Pain, bleeding, and the need for manual reduction of the hemorrhoids were all improved in both groups after 1 year (p < 0.05). Soiling had decreased after both methods at early follow-up. After 1 year, soiling was significantly decreased only after open hemorrhoidectomy. The grade of hemorrhoids was significantly reduced after 1 year for both methods, but there was a trend to more patients with remaining grade 2 hemorrhoids in group A (p = 0.06). LIMITATIONS: There was no blinding, the sample size was small, and follow-up was for only 1 year. The questionnaire was not validated. CONCLUSION: The difference in postoperative pain between transanal hemorrhoidal dearterialization with anopexy and open hemorrhoidectomy may be less than expected based on previous literature.

Common variants in human CRC genes as low-risk alleles.

The genetic susceptibility to colorectal cancer (CRC) has been estimated to be around 35% and yet high-penetrance germline mutations found so far explain less than 5% of all cases. Much of the remaining variations could be due to the co-inheritance of multiple low penetrant variants. The identification of all the susceptibility alleles could have public health relevance in the near future. To test the hypothesis that what are considered polymorphisms in human CRC genes could constitute low-risk alleles, we selected eight common SNPs for a pilot association study in 1785 cases and 1722 controls. One SNP, rs3219489:G>C (MUTYH Q324H) seemed to confer an increased risk of rectal cancer in homozygous status (OR=1.52; CI=1.06-2.17). When the analysis was restricted to our 'super-controls', healthy individuals with no family history for cancer, also rs1799977:A>G (MLH1 I219V) was associated with an increased risk in both colon and rectum patients with an odds ratio of 1.28 (CI=1.02-1.60) and 1.34 (CI=1.05-1.72), respectively (under the dominant model); while 2 SNPs, rs1800932:A>G (MSH6 P92P) and rs459552:T>A (APC D1822V) seemed to confer a protective effect. The latter, in particular showed an odds ratio of 0.76 (CI=0.60-0.97) among colon patients and 0.73 (CI=0.56-0.95) among rectal patients. In conclusion, our study suggests that common variants in human CRC genes could constitute low-risk alleles.

Different biological materials are found in neoplastic glands with pores at the invading edge of sporadic colonic carcinomas.

BACKGROUND: Studying the invading edge of colorectal carcinomas it was previously noticed that the neoplastic glands with pores could contain mucin, inflammatory cells and/or necrotic material. AIMS: To systematically record the type of intraglandular materials found in the neoplastic glands with pores at the invading edge of sporadic colonic carcinomas. MATERIALS AND METHODS: Histological sections from 12 adenocarcinomas were selected when the following materials were predominantly found in the neoplastic glands with pores at the invading tumor edge: mucin (3 cases, group I), neutrophilic granulocyes (3 cases, group II), necrotic material (3 cases, group III) and invaginated stroma (3 cases, group IV). Surgical histological sections were stained with hematoxylin and eosin (H&E) and analyzed at 20 magnifications. The length of the invading edge was measured with a translucent millimetre ruler and the number of glands with pores per mm was calculated in each case. RESULTS: Two hundred and ninety-five glands with pores were analyzed in the 12 cases. Mucus was found in 68% (n=55) of the 81 glands with pores in group I, granulocytes in 95% (n=41) of the 43 glands with pores in group II, necrotic material in 72% (n=84) of the 117 glands with pores in group III and stromal invaginations in 61% (n=33) of the 54 glands with pores in group IV. The mean number of glands with pores per mm was 1.02 (55 glands/54 mm) in group I, 0.93 (41 glands/44 mm) in group II, 1.22 (84 glands /69 mm) in group III and 0.62 (33 glands /53 mm) in group IV. DISCUSSION AND CONCLUSION: Neoplastic glands with pores at the invading front of colonic adenocarcinomas may predominantly contain various biological materials. These materials may differ in different individuals. While tumor mucins harbour proteolytic enzymes able to digest the juxtaposed stroma of the host, the possible significance of the other intraglandular materials contributed by the host, such as neutrophils, necrotic material and/or stromal invaginations on tumor growth, is still poorly understood. Further studies are necessary to assess whether each one of these intraglandular materials has any bearing on the progression of colonic carcinomas.

Lack of an association between the TGFBR1*6A variant and colorectal cancer risk.

PURPOSE: Recently a common variant of the TGFBR1 gene, TGFBR1*6A, has been proposed to act as a low-penetrance tumor susceptibility allele for colorectal cancer, but data from published studies with individually low statistical power are conflicting. To further evaluate the relationship between TGFBR1*6A and colorectal cancer risk, we have conducted a large case-control study and a meta-analysis of previously published studies. EXPERIMENTAL DESIGN: A total of 1,042 colorectal cancer cases and 856 population controls were genotyped for the TGFBR1*6A polymorphism. Previously published case-control studies of the relationship between TGFBR1*6A and colorectal cancer were identified, and a meta-analysis was conducted. RESULTS: We found no evidence that homozygosity, heterozygosity or carrier status for the TGFBR1*6A allele confers an increased risk of colorectal cancer; respective odds ratios (OR) were 1.05 [95% confidence interval (95% CI), 0.83-1.32], 0.82 (95% CI, 0.34-1.99), and 0.92 (95% CI, 0.74-1.15), respectively. A meta-analysis of our case-control study and seven other studies that provided data on 2,627 colorectal cancer cases and 3,387 controls also yielded no evidence that possession of the TGFBR1*6A allele is associated with an elevated risk of colorectal cancer; pooled estimate of the OR were 1.20 (95% CI, 0.64-2.24) for homozygosity, 1.11 (95% CI, 0.96-1.29) for heterozygosity, and 1.13 (95% CI, 0.98-1.30) for carriers of TGFBR1*6A. CONCLUSION: Current data provide limited support for the hypothesis that sequence variation in TGFBR1 defined by the TGFBR1*6A allele confers an elevated risk of colorectal cancer.

Prognostic significance of Cyclin A in epidermoid anal cancer.

Ultimately aiming at a more individualized therapeutic approach in epidermoid anal cancer, this study explored the prognostic and predictive impact of a set of tumour markers. From a population-based cohort of 276 patients with epidermoid anal cancer, treated according to prospective protocols, 215 pre-treatment biopsies were investigated using immunohistochemistry. The expression of p53, p21, Cyclin A and CD31 was measured semi-quantitatively. The expression rate was classified as high when immunostaining was seen in > 5% of the tumour cells for p53 and p21, > 20% in Cyclin A and, above median vessel count for CD31. Marker expression was correlated to survival and treatment response. A high Cyclin A expression correlated significantly with improved overall (77% vs 59%, p = 0.005) and tumour-specific (81% vs 64%, p = 0.009) survival at 5 years. Also, the locoregional failure rate was significantly lower in patients with a high Cyclin A expression (12% vs 24%, p < 0.05). In a multivariate Cox analysis Cyclin A was an independent prognostic factor. A low p21 expression correlated with a reduced rate of locoregional failure (14% vs 27%, p < 0.05) but no impact on survival was found. For p53 and CD31 no significant correlations were obtained. Cyclin A may be an indicator of radiosensitivity and a valuable prognostic marker in epidermoid anal cancer.

The CHEK2 1100delC variant in Swedish colorectal cancer.

BACKGROUND: The cell cycle checkpoint kinase 2 (CHEK2) 1100delC variant has recently been identified at high frequency in families with both breast and colorectal cancer, suggesting the possible role of this variant in colorectal cancer predisposition. PATIENTS AND METHODS: To evaluate the role of CHEK2 ll00delC among Swedish colorectal cancer patients, the variant frequency was determined in 174 selected familial cases, 644 unselected cases and 760 controls, as well as in l8 families used in the genome-wide linkage analysis, where weak linkage was seen for the region harboring the CHEK2 gene. RESULTS: CHEK2 l100delC was found in 1.15% of familial and in 0.93% of unselected cases, compared to 0.66% of controls, showing no significant difference between groups. One out of 45 familial cases with a family history of breast cancer was shown to be a carrier. The variant was not identified in the 18 families included in the linkage analysis. CONCLUSION: The CHEK2 1100delC was not significantly increased in Swedish colorectal cancer patients, however, in order to determine the role of the variant in colorectal cancer families with the history of breast cancer a larger sample size is needed.

Reliability of the reported size of removed colorectal polyps.

BACKGROUND: The size of colorectal polyps is important in the clinical management of these lesions. AIM: To audit the accuracy in calculating the size of "polyps" by various specialists. MATERIALS AND METHODS: Eighteen pathologists and four surgeons measured, with a conventional millimetre ruler, the largest diameter of 12 polyp phantoms. The results of two independent measurements (two weeks apart) were compared with the gold standard-size assessed at The Royal Institute of Technology, Sweden. RESULTS: Thirty-one percent (83/264-trial 1) and 33% (88/264-trial 2) of the measurements underestimated or overestimated the gold standard size by >1 mm. Of the 22 experienced participants, 95% (21/22-trial 1) and 91% (20/22-trial 2) misjudged by >1 mm the size of one or more polyps. Values given by 13 participants (4.9%) in trial 1 and by 15 participants (5.7%) in trial 2, differed by > or = +/-4 mm from the gold standard size. In addition, a big difference between the highest and the lowest values was recorded in some polyps (up to 11.4 mm). Those disparate values were regarded as a human error in reading the scale on the ruler. CONCLUSION: Using a conventional ruler (the tool of pathologists worldwide) unacceptably high intra-observer and inter-observer variations in assessing the size of polyp-phantoms was found. The volume and the shape of devices, as well as human error in reading the scale of the ruler were confounding factors in size assessment. In praxis, the size is crucial in the management of colorectal polyps. Considering the clinical implications of the results obtained, the possibility of developing a method that will allow assessment of the true size of removed clinical polyps is being explored.