Are Metastatic Central Lymph Nodes (D3 volume) in right-sided Colon Cancer a Sign of Systemic Disease? A sub-group Analysis of an Ongoing Multicenter Trial.

OBJECTIVE: Assess outcomes of patients with right-sided colon cancer with metastases in the D3 volume after personalized surgery. BACKGROUND: Patients with central lymph node metastasis (D3-PNG) are considered to have a systemic disease with a poor prognosis. A 3-dimensional definition of the dissection volume allows the removal of all central nodes. MATERIALS AND METHODS: D3-PNG includes consecutive patients from an ongoing clinical trial. Patients were stratified into residual disease negative (D3-RDN) and residual disease positive (D3-RDP) groups. D3-RDN was further stratified into 4 periods to identify a learning curve. A personalized D3 volume (defined through arterial origins and venous confluences) was removed " en bloc" through medial-to-lateral dissection, and the D3 volume of the specimen was analyzed separately. RESULTS: D3-PNG contained 42 (26 females, 63.1 SD 9.9 y) patients, D3-RDN:29 (17 females, 63.4 SD 10.1 y), and D3-RDP:13 (9 females, 62.2 SD 9.7 y). The mean overall survival (OS) days were D3-PNG:1230, D3-RDN:1610, and D3-RDP:460. The mean disease-free survival (DFS) was D3-PNG:1023, D3-RDN:1461, and D3-RDP:74 days. The probability of OS/DFS were D3-PNG:52.1%/50.2%, D3-RDN:72.9%/73.1%, D3-RDP: 7.7%/0%. There is a significant change in OS/DFS in the D3-RDN from 2011-2013 to 2020-2022 (both P =0.046) and from 2014-2016 to 2020-2022 ( P =0.028 and P =0.005, respectively). CONCLUSION: Our results indicate that surgery can achieve survival in most patients with central lymph node metastases by removing a personalized and anatomically defined D3 volume. The extent of mesenterectomy and the quality of surgery are paramount since a learning curve has demonstrated significantly improved survival over time despite the low number of patients. These results imply a place for the centralization of this patient group where feasible.

DNA Repair Protein Expression and Oxidative/Nitrosative Stress in Ulcerative Colitis and Sporadic Colorectal Cancer.

BACKGROUND/AIM: Chronic inflammation generates large quantities of reactive oxygen and nitrogen species that damage DNA. DNA repair is important for cellular viability and genome integrity. MATERIALS AND METHODS: Expression levels of the DNA repair proteins OGG1, XPA, MLH1, PARP1, and XRCC6, which function in base excision repair, nucleotide excision repair, mismatch repair, single-strand break repair and double-strand break repair, respectively, were assessed using immunohistochemistry in ulcerative colitis and sporadic colorectal cancer biopsies. Levels of oxidative/ nitrosative stress biomarkers were also assessed. RESULTS: Ulcerative colitis and colorectal cancer lesions expressed significantly higher levels of all DNA repair proteins and oxidative/ nitrosative stress biomarkers compared to normal colonic mucosa. Ulcerative colitis had the highest XPA and XRCC6 expression. CONCLUSION: Oxidative/nitrosative stress is prevalent in the colon of both diseases. Nucleotide excision repair and non-homologous end-joining double-strand break repair may be compromised in colorectal cancer, but not in ulcerative colitis.

Role of the Wnt signaling pathway in keratoacanthoma.

BACKGROUND: Keratoacanthoma (KA) has a unique life cycle of rapid growth and spontaneous regression that shows similarities to the hair follicle cycle, which involves an active Wnt signaling during physiological regeneration. We analyzed the expression of the Wnt signaling proteins ß-catenin, Lef1, Sox9, and Cyclin D1 in young and old human KAs to investigate a possible role for Wnt signaling in KAs. AIM: To investigate the role of the Wnt/ß-catenin signaling pathway in human KAs. METHODS AND RESULTS: Formalin-fixed, paraffin-embedded tissue samples of 67 KAs were analyzed for protein expression using immunohistochemistry. The majority of KAs were positive for Sox9 and Cyclin D1 but not for nuclear-localized ß-catenin or Lef-1. No significant differences in protein expressions were seen between young and old KAs. However, we found a significant association between Ki67 and Cyclin D1 proteins (P= .008). CONCLUSIONS: The Wnt signaling pathway does not appear to play a significant role in the biogenesis of human KA. Sox9 overexpression may be indicative of inhibition of Wnt signaling. Sox-9 and Cyclin D1 are proliferation markers that are most likely transactivated by alternate signaling pathways.

Induction of Apoptosis in Intestinal Toxicity to a Histone Deacetylase Inhibitor in a Phase I Study with Pelvic Radiotherapy.

PURPOSE: When integrating molecularly targeted compounds in radiotherapy, synergistic effects of the systemic agent and radiation may extend the limits of patient tolerance, increasing the demand for understanding the pathophysiological mechanisms of treatment toxicity. In this Pelvic Radiation and Vorinostat (PRAVO) study, we investigated mechanisms of adverse effects in response to the histone deacetylase (HDAC) inhibitor vorinostat (suberoylanilide hydroxamic acid, SAHA) when administered as a potential radiosensitiser. MATERIALS AND METHODS: This phase I study for advanced gastrointestinal carcinoma was conducted in sequential patient cohorts exposed to escalating doses of vorinostat combined with standard-fractionated palliative radiotherapy to pelvic target volumes. Gene expression microarray analysis of the study patient peripheral blood mononuclear cells (PBMC) was followed by functional validation in cultured cell lines and mice treated with SAHA. RESULTS: PBMC transcriptional responses to vorinostat, including induction of apoptosis, were confined to the patient cohort reporting dose-limiting intestinal toxicities. At relevant SAHA concentrations, apoptotic features (annexin V staining and caspase 3/7 activation, but not poly-(ADP-ribose)-polymerase cleavage) were observed in cultured intestinal epithelial cells. Moreover, SAHA-treated mice displayed significant weight loss. CONCLUSION: The PRAVO study design implemented a strategy to explore treatment toxicity caused by an HDAC inhibitor when combined with radiotherapy and enabled the identification of apoptosis as a potential mechanism responsible for the dose-limiting effects of vorinostat. To the best of our knowledge, this is the first report deciphering mechanisms of normal tissue adverse effects in response to an HDAC inhibitor within a combined-modality treatment regimen.

Tp53/p53 status in keratoacanthomas.

BACKGROUND: Keratoacanthoma (KA) is a common keratinocytic skin neoplasm that typically develops rapidly and undergoes complete spontaneous regression. As the pro-apoptotic p53 protein may be involved in the lifecycle of KA, we studied the p53 status throughout the main stages of KA that include proliferation, maturation and regression in a large series of lesions. METHODS: One-hundred and twenty-four KAs were characterized with respect to age of the lesions both clinically and histopathologically, in addition to phenotypic characteristics such as cellular atypia, infiltration, inflammation and fibrosis. Tp53 mutations were detected by capillary electrophoresis, and p53 protein levels were assessed by immunohistochemistry. RESULTS: Tp53 mutations were detected in 49 cases (39.5%) and were associated with high p53 protein levels (p = 0.007) and histopathologic age of the lesions (p = 0.044). Significant association was also seen between high p53 protein levels and atypia (p = 0.036), whereas the association with infiltration showed borderline significance (p = 0.057). High p53 protein levels were significantly associated with gene mutations in transplanted, but not in non-transplanted patients. CONCLUSION: We show a high frequency of Tp53 mutations in KAs that is associated with increased p53 levels. The results indicate a role for the p53 protein in KA development.

The endothelin axis in the metastatic process of colon carcinoma.

BACKGROUND: The endothelin axis has recently emerged as an important factor in tumour metastasis. The aim of this study was to investigate the endothelin axis and its downstream pathways related to metastasis in colon carcinoma. MATERIALS AND METHODS: mRNA expression of 36 genes associated with the endothelin axis in 18 non-metastatic and 20 metastatic colon carcinomas with individual-matched normal mucosa were evaluated using real-time reverse transcription polymerase chain reaction. RESULTS: Seventeen out of 36 genes, including endothelin A receptor, were significantly overexpressed in the tumour tissue compared to the individual-matched normal mucosa. Seven out of 36 genes, including endothelin B receptor, were significantly down-regulated in tumour tissue. Phosphatase and tensin homolog (PTEN) was significantly down-regulated in the metastatic patients compared to the non-metastatic patients. CONCLUSION: This study indicated that central genes in the endothelin axis are overexpressed when colon tissue becomes malignant. Down-regulation of PTEN may promote a progressive phenotype of colon carcinomas.

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.

The Prognostic Impact of Protein Expression of E-Cadherin-Catenin Complexes Differs between Rectal and Colon Carcinoma.

The E-cadherin-catenin complex provides cell-cell adhesion. In order for a carcinoma to metastasize, cancer cells must let go of their hold of neighboring cells in the primary tumor. The presence of components of the E-cadherin-catenin complex in 246 rectal adenocarcinomas was examined by immunohistochemistry and compared to their presence in 219 colon carcinomas. The expression data were correlated to clinical information from the patients' records. There were statistically significant differences in protein expression between the rectal and the colon carcinomas regarding membranous beta-catenin, gamma-catenin, p120-catenin, and E-cadherin, as well as nuclear beta-catenin. In the rectal carcinomas, there was a significant inverse association between the expression of p120-catenin in cell membranes of the primary tumors and the occurrence of local recurrence, while membranous protein expression of beta-catenin was inversely related to distant metastases.

Widespread but not localized neoplasia in inflammatory bowel disease worsens the prognosis of colorectal cancer.

BACKGROUND: Patients with inflammatory bowel disease (IBD) are at increased risk of colorectal cancer (CRC). Recently, new phenotypes of CRC in IBD have been suggested. Studies of the prognosis of CRC in IBD have shown conflicting results. The aim of the study was to analyze factors for prognosis in CRC-IBD, including the impact of the new phenotypes. METHODS: By using the nationwide, population-based Cancer Registry of Norway, we compared survival of a CRC-IBD cohort with CRC in the background population (all-CRC), adjusting for the topographical distribution of dysplasia at cancer diagnosis (widespread versus localized neoplasia in IBD) and other factors. We also analyzed prognostic factors within CRC-IBD. RESULTS: The mean age at CRC diagnosis was 43 years in widespread, 52 years in localized neoplasia IBD, and 70 years in all-CRC (P < 0.05). Adjusted for cofactors, prognosis of CRC-IBD was poorer compared to all-CRC (mortality rate ratio [MRR] 3.71, 95% confidence interval [CI]: 2.54-5.42, P < 0.001). Prognosis of widespread neoplasia IBD was poorer compared to all-CRC (MRR 4.27, 95% CI: 2.83-6.44, P < 0.001) and compared to localized neoplasia IBD (MRR 3.58, 95% CI: 0.87-14.72, P = 0.076). Survival was not significantly different between localized neoplasia IBD and all-CRC (P = 0.132). CONCLUSIONS: The results demonstrate lower age and poorer survival of CRC in IBD compared to CRC in the background population. The unfavorable effect of IBD on prognosis of CRC was pronounced in widespread neoplasia IBD. The diagnosis of this phenotype seems to be an important prognostic sign in patients with CRC in IBD.

Differences in protein expression and gene amplification of cyclins between colon and rectal adenocarcinomas.

Adenocarcinomas of rectum and colon may be different with regard to the cellular biological basis for cancer development. A material of 246 rectal cancers removed surgically at Akershus University Hospital in the years 1992-2000 was investigated and was compared to a material of 219 colon cancers operated on at Akershus University Hospital during the years 1988, 1990 and 1997-2000. There were highly significant differences between the rectal and the colon cancers in the protein expression of cyclin D1, cyclin D3, cyclin E, nuclear beta-catenin, and c-Myc and in gene amplification of cyclin A2, cyclin B1, cyclin D1, and cyclin E. Gene amplification and protein expression in the rectal cancers correlated significantly for the cyclins B1, D3, and E. A statistically significant relation was observed between overexpression of cyclin A2 and local relapse of rectal carcinomas, as higher expression of cyclin A2 was associated with lower local recurrence rate.

Two distinct groups of colorectal cancer in inflammatory bowel disease.

BACKGROUND: The histological variability in colitis-associated colorectal cancer (CRC in inflammatory bowel disease [IBD]) and the association to clinical factors is unknown. METHODS: In population-based material including 67 patients with CRC in IBD, histopathology of the cancers and tissue samples from different colorectal localizations were reevaluated, and relationships to clinical factors analyzed. RESULTS: Forty-three of 60 patients (75%) showed dysplasia in the colorectum apart from the cancer, while 17 (25%) had no dysplasia at cancer diagnosis. Mean age at onset of IBD was 22 years in patients with and 34 years in patients without dysplasia (P = 0.01). The mean duration of colitis-CRC interval was 21 years in patients with and 16 years in patients without dysplasia (P = 0.02). The latter group included all patients with a colitis-CRC interval <10 years. Active inflammation was more likely to occur in patients with dysplasia (odds ratio [OR] 4.2). The 2 groups were not discriminated by gender, family history of CRC or IBD, diagnosis of PSC, medical treatment, active symptoms, or histological features like type of cancer and differentiation. In multiple logistic regression analysis the age at onset of IBD was the strongest predictive variable for dysplasia at cancer diagnosis (P = 0.025). CONCLUSIONS: Widespread neoplasia occurs in the majority of cases with CRC in IBD and is associated with early onset of IBD. Localized neoplasia occurs in about a quarter of the patients and shows an association with late-onset IBD. The 2 groups probably represent different pathogenetic entities of neoplasia in IBD. This might have consequences for surveillance strategies.

Sentinel node mapping does not improve staging of lymph node metastasis in colonic cancer.

PURPOSE: This study was designed to evaluate the reliability of the sentinel node concept in colonic cancer. METHODS: Patent blue was used as tracer. The four blue nodes closest to the tumor were defined as the sentinel node(s) by the pathologist. All nodes were examined by routine microscopy (hematoxylin-eosin staining). If no metastases were detected, all lymph nodes were examined immunohistochemically with antibody to cytokeratin. RESULTS: Two hundred colon specimens were examined. Sentinel node(s) were identified in 93 percent. Sixty contained metastases in hematoxylin-eosin sections. In 32 these were found in sentinel nodes (sensitivity 53 percent). Twenty-eight patients had metastases in nonsentinel nodes only, giving a false-negative rate of 47 percent. Immunostaining revealed 39 (30 percent) micrometastases or submicrometastases in 131 TNM Stages I and II patients, and in 17 of these patients metastases were found in nonsentinel nodes only (false-negative rate 44 percent). CONCLUSIONS: Sentinel lymph node mapping shows low sensitivity for detection of ordinary metastases, micrometastases, and submicrometastases. If only the sentinel nodes had been examined, approximately half of the metastases would have been lost after routine staining, as well as half of the micrometastases and submicrometastases when immunohistochemical examination was added.

[Colorectal polyps]. / Kolorektale polypper.

BACKGROUND: Colorectal polyps are common, but there is a large geographical variation--and Norway has one of the highest incidences. There is circumstantial evidence that most cancers develop from polyps; so detection, eradication and follow-up stategies for polyps are important. The article provides an update on these topics. MATERIAL AND METHODS: The article is based on the authors' own research and clinical experience, and on literature retrieved through a non-systematic search of Pubmed. RESULTS AND INTERPRETATION: Classification of polyps is based on morphology and histology, and the risk of malignancy depends on both. Colonoscopy is the primary method for detection of polyps; biopsies can be taken and treatment initiated during the procedure. CT colography (virtual colonoscopy) may be on the verge of becoming a diagnostic tool. Pedunculated polyps are usually removed by endoscopical snare resection, which is sufficient even when cancer has developed in the head of the polyp. Large sessile polyps, with considerable risk of malignancy, may be removed by transanal endoscopic microsurgery in the rectum, while surgical localised resection will often be required in the colon. Between these extremes, many polyps may be removed by more advanced endoscopic techniques, and at times with supplementary ablation.

Microsatellite instability in long-standing ulcerative colitis.

OBJECTIVE: Ulcerative colitis (UC) is a chronic inflammatory disease of the colon associated with a high risk of developing colorectal cancer. Several genetic alterations have been documented in dysplasia and cancer developing in UC. Concerning microsatellite instability (MSI), many contradictory results have been published. We therefore analysed a large, well-characterized UC material for MSI to elucidate its significance in long-standing UC. MATERIAL AND METHODS: From 33 patients, a total of 159 microdissected lesions and 165 mucosa samples obtained adjacent to the tissue blocks were analysed for MSI using the five standard markers recommended by the National Cancer Institute; D2S123, D5S346, D17S250, BAT-25 and BAT-26. In addition, 12 of the patients were investigated by a mini-satellite marker at the D1S7 locus. RESULTS: High-level MSI (MSI-H) was detected in one villous adenoma with high-grade dysplasia and right-sided location. This represents 3.6% (1/28) of dysplastic mucosa investigated. No other lesions showed MSI in the five standard markers or at the D1S7 locus. CONCLUSIONS: This study suggests that MSI is rare in UC-related neoplasia as well as non-neoplastic lesions, and does not contribute to the development of dysplasia.

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

PURPOSE: This 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 (< or =6 cm from anal verge) and high (>6 cm) rectal cancers. METHODS: A total of 140 patients (81 males; median age, 64 (range, 29-87) years) underwent surgery for rectal cancer under curative intention. RESULTS: Local 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. CONCLUSIONS: Surgery 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.

Mitochondrial microsatellite instability in colorectal carcinomas--frequency and association with nuclear microsatellite instability.

The D310 mononucleotide repeat in the D-loop region in mitochondrial DNA has been identified as a hotspot for alterations in primary tumours. We examined D310 alterations as well as repeats in the ND1 and ND5 genes, in 95 colorectal carcinomas and in 95 controls without known gastrointestinal malignancy. D310 alterations were found in 32 (34%) of the carcinomas, in contrast to two persons (2%) in the control group. Thus, when frequency is concerned, D310 seems to be a hotspot for alterations in colorectal cancer. No mutations were found in the ND1 and ND5 genes. D310 instability was not associated with nuclear microsatellite instability, indicating different mechanisms of occurrence.