The Transcriptional Landscape of Coding and Noncoding RNAs in Recurrent and Nonrecurrent Colon Cancer.

A number of patients with colon cancer with local or local advanced disease suffer from recurrence and there is an urgent need for better prognostic biomarkers in this setting. Here, the transcriptomic landscape of mRNAs, long noncoding RNAs, snRNAs, small nucleolar RNAs (snoRNAs), small Cajal body-specific RNAs, pseudogenes, and circular RNAs, as well as RNAs denoted as miscellaneous RNAs, was profiled by total RNA sequencing. In addition to well-known coding and noncoding RNAs, differential expression analysis also uncovered transcripts that have not been implicated previously in colon cancer, such as RNA5SP149, RNU4-2, and SNORD3A. Moreover, there was a profound global up-regulation of snRNA pseudogenes, snoRNAs, and rRNA pseudogenes in more advanced tumors. A global down-regulation of circular RNAs in tumors relative to normal tissues was observed, although only a few were expressed differentially between tumor stages. Many previously undescribed transcripts, including RNU6-620P, RNU2-20P, VTRNA1-3, and RNA5SP60, indicated strong prognostic biomarker potential in receiver operating characteristics analyses. In summary, this study unveiled numerous differentially expressed RNAs across various classes between recurrent and nonrecurrent colon cancer. Notably, there was a significant global up-regulation of snRNA pseudogenes, snoRNAs, and rRNA pseudogenes in advanced tumors. Many of these newly discovered candidates demonstrate a strong prognostic potential for stage II colon cancer.

Proteomic Profiling of Colorectal Adenomas Identifies a Predictive Risk Signature for Development of Metachronous Advanced Colorectal Neoplasia.

BACKGROUND & AIMS: Colonic adenomatous polyps, or adenomas, are frequent precancerous lesions and the origin of most cases of colorectal adenocarcinoma. However, we know from epidemiologic studies that although most colorectal cancers (CRCs) originate from adenomas, only a small fraction of adenomas (3%-5%) ever progress to cancer. At present, there are no molecular markers to guide follow-up surveillance programs. METHODS: We profiled, by mass spectrometry-based proteomics combined with machine learning analysis, a selected cohort of formalin-fixed, paraffin-embedded high-grade (HG) adenomas with long clinical follow-up, collected as part of the Danish national screening program. We grouped subjects in the cohort according to their subsequent history of findings: a nonmetachronous advanced neoplasia group (G0), with no new HG adenomas or CRCs up to 10 years after polypectomy, and a metachronous advanced neoplasia group (G1) where individuals developed a new HG adenoma or CRC within 5 years of diagnosis. RESULTS: We generated a proteome dataset from 98 selected HG adenoma samples, including 20 technical replicates, of which 45 samples belonged to the nonmetachronous advanced neoplasia group and 53 to the metachronous advanced neoplasia group. The clear distinction of these 2 groups seen in a uniform manifold approximation and projection plot indicated that the information contained within the abundance of the ∼5000 proteins was sufficient to predict the future occurrence of HG adenomas or development of CRC. CONCLUSIONS: We performed an in-depth analysis of quantitative proteomic data from 98 resected adenoma samples using various novel algorithms and statistical packages and found that their proteome can predict development of metachronous advanced lesions and progression several years in advance.

Delta tocotrienol as a supplement to FOLFOXIRI in first-line treatment of metastatic colorectal cancer. A randomized, double-blind, placebo-controlled phase II study.

PURPOSE: Triplet chemotherapy might be more effective than doublet chemotherapy in metastatic colorectal cancer (mCRC), but it may also be marked by increased toxicity. To investigate whether δ-tocotrienol, a vitamin E analogue, with possible neuroprotective and anti-inflammatory effects, reduces the toxicity of triplet chemotherapy, we conducted a randomized, double-blind, placebo-controlled trial in mCRC patients receiving first-line 5-fluorouracil, oxaliplatin and irinotecan (FOLFOXIRI). MATERIAL AND METHODS: Seventy patients with mCRC were randomly assigned (1:1) to receive FOLFOXIRI plus either δ-tocotrienol or placebo at the Department of Oncology, Vejle Hospital, Denmark. Eligibility criteria were adenocarcinoma in the colon or rectum, age 18-75 years and ECOG performance status 0-1. FOLFOXIRI was given in eight cycles followed by four cycles of 5-fluorouracil. δ-tocotrienol 300 mg or placebo × 3 daily was added during chemotherapy and for a maximum of two years. The primary endpoint was time to hospitalization or death during treatment with chemotherapy. RESULTS: Median time to first hospitalization or death was 3.7 months in the placebo group (95% CI 1.93-not reached (NR)), and was NR in the δ-tocotrienol group (95% CI 1.87-NR) with a hazard ratio of 0.70 (95% CI 0.36-1.36). Grade 3-4 toxicities were uncommon in both groups, except for neutropenia, which occurred in 19 patients (58%) in the placebo group and 17 patients (50%) in the δ-tocotrienol group. There were no grade 3 or 4 peripheral sensory neuropathy. In the placebo group, 24 patients (71%) had oxaliplatin dose reductions compared to 17 patients (47%) in the δ-tocotrienol group (p = 0.047). CONCLUSION: The addition of δ-tocotrienol to FOLFOXIRI did not statistically significant prolong the time to first hospitalization or death compared to FOLFOXIRI plus placebo. Toxicity was manageable and not statistically different. There was a statistically significant difference in dose reductions of oxaliplatin pointing to a possible neuroprotective effect of δ-tocotrienol.

Randomized Phase II trial of combination chemotherapy with panitumumab or bevacizumab for patients with inoperable biliary tract cancer without KRAS exon 2 mutations.

Biliary tract cancers (BTC) are rare and often diagnosed in late stages with advanced, nonresectable disease. The targeted agents panitumumab and bevacizumab have shown promising outcomes in combination with chemotherapy in other gastrointestinal (GI) cancers. We wanted to investigate if panitumumab or bevacizumab was the most promising drug to add to chemotherapy. Eighty-eight patients were randomized to combination chemotherapy supplemented by either panitumumab 6 mg/kg or bevacizumab 10 mg/kg on Day 1 in Arm A and Arm B, respectively. All patients received gemcitabine 1000 mg/m2 on Day 1, oxaliplatin 60 mg/m2 on Day 1 and capecitabine 1000 mg/m2 twice daily from Days 1 to 7. Treatment was repeated every 2 weeks until progression or for a maximum of 6 months. At progression, crossover was made to the other treatment arm. The primary endpoint was progression-free survival (PFS) at 6 months. With 19 of 45 in Arm A and 23 of 43 in Arm B PFS at 6 months, the primary endpoint was not met. The overall response rate (ORR) was 45% vs 20% (P = .03), median PFS was 6.1 months vs 8.2 months (P = .13) and median overall survival (OS) was 9.5 months vs 12.3 months (P = .47) in Arm A and Arm B, respectively. Our study showed no consistent differences between adding panitumumab or bevacizumab to chemotherapy in nonresectable BTC and none of the two regimens qualify for testing in Phase III. However, we found a higher response rate in the panitumumab arm with potential implication for future trials in the neoadjuvant setting.

A streamlined mass spectrometry-based proteomics workflow for large-scale FFPE tissue analysis.

Formalin fixation and paraffin-embedding (FFPE) is the most common method to preserve human tissue for clinical diagnosis, and FFPE archives represent an invaluable resource for biomedical research. Proteins in FFPE material are stable over decades but their efficient extraction and streamlined analysis by mass spectrometry (MS)-based proteomics has so far proven challenging. Herein we describe a MS-based proteomic workflow for quantitative profiling of large FFPE tissue cohorts directly from histopathology glass slides. We demonstrate broad applicability of the workflow to clinical pathology specimens and variable sample amounts, including low-input cancer tissue isolated by laser microdissection. Using state-of-the-art data dependent acquisition (DDA) and data independent acquisition (DIA) MS workflows, we consistently quantify a large part of the proteome in 100 min single-run analyses. In an adenoma cohort comprising more than 100 samples, total workup took less than a day. We observed a moderate trend towards lower protein identification in long-term stored samples (>15 years), but clustering into distinct proteomic subtypes was independent of archival time. Our results underscore the great promise of FFPE tissues for patient phenotyping using unbiased proteomics and they prove the feasibility of analyzing large tissue cohorts in a robust, timely, and streamlined manner. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Long-term risk of colorectal cancer after screen-detected adenoma: Experiences from a Danish gFOBT-positive screening cohort.

Fecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all FOBT-positive persons have screen-detected adenomas. Despite removal of these, patients with large/multiple adenomas have increased risk of later developing new advanced adenomas and CRC. International guidelines exist for colonoscopic surveillance following adenoma removal. These divide patients into low-, intermediate- and high-risk groups. We followed 711 FOBT-positive patients with screening adenoma identified during population-based CRC screening in two Danish counties in 2005-2006. As reference population, we included 1,240,348 persons in the same age group from the rest of Denmark not included in the screening. We estimated the long-term CRC risk stratified by adenoma findings during screening and compared to the reference group. After 12 years follow-up, the CRC incidence among all adenoma patients was 322 cases per 100,000 person-years (95% confidence interval [CI]: 212-489) ranging from 251 (95% CI: 94-671) to 542 (95% CI: 300-978) cases per 100,000 person-years in the low- and high-risk groups, respectively. In the reference population, the CRC incidence was 244 (95% CI: 242-247) per 100,000. Patients with screen-detected high-risk adenomas after a positive FOBT had an almost doubled risk of CRC compared to the reference population (adjusted hazard ratio [aHR] 1.95, 95% CI: 1.08-3.51), and the incidence in those with no follow-up visits was over 3.6 (aHR 3.64, 95% CI: 1.82-7.29) times the incidence in the reference population. The increased CRC risk could be controlled if high-risk patients underwent follow-up colonoscopy (aHR 0.87, 95% CI: 0.28-2.69).

Phase II study of gemcitabine, oxaliplatin and capecitabine in patients with KRAS exon 2 mutated biliary tract cancers.

Background: Molecular markers may identify subgroups of patients with clinically distinct behavior and response to treatment. In some gastrointestinal tumors, KRAS has prognostic value and negative predictive value. This is the first prospective study to report the outcome of combination chemotherapy in biliary tract cancer patients with KRAS mutation.Methods: From 2009 to 2015, 25 patients were included from two Scandinavian centers. Main inclusion criteria were non-resectable biliary tract cancer, ECOG performance status 0-2 and tumor KRAS mutation. A bi-weekly cycle of chemotherapy was administered as gemcitabine 1000 mg/m2 and oxaliplatin 85 mg/m2 day 1, followed by 7 days of oral capecitabine 1000 mg/m2. Response evaluation was done every six treatment and the primary endpoint was the fraction with progression free survival (PFS) at 6 months. The study also included a non-preplanned analysis of circulating tumor specific DNA.Results: Chemotherapy was given for a median of 5 months (range 0-14) and among 17 patients evaluable for response, best responses were complete response (1), partial response (2), and stable disease (14). Eighteen patients had CT-verified progression, six died between evaluations and one patient is still progression-free. Median PFS was 6.8 months (95% CI 3.1-11.0) and median overall survival (OS) was 11.2 months (95% CI 6.6-14.3). The fraction with PFS at 6 months was 52% (95% CI 31-69%). Exploratory analyses found an improved survival in patients with a low level of plasma DNA.Conclusion: Pretreatment molecular characterization was feasible in BTC, but the rate of KRAS mutations was low. The study met its primary endpoint with a fraction of PFS at six months of 52%. The effect of combination chemotherapy with gemcitabine, oxaliplatin and capecitabine in this selected population was comparable to results from unselected groups with PFS and OS of 6.8 and 11.2 months, respectively. ClinicalTrials.gov NCT00779454.

Programmed Death Ligand-1 expression in stage II colon cancer - experiences from a nationwide populationbased cohort.

BACKGROUND: Patients suffering from high risk stage II colon cancer (CC) may benefit from adjuvant onco-therapy, but additional prognostic markers are needed for better treatment stratification. We investigated the prognostic value of Programmed Death Ligand-1 (PD-L1) in a true population-based cohort of patients with stage II CC. METHODS: PD-L1 expression on tumour cells was evaluated by immunohistochemistry in 572 colon cancers. Whole sections from tumour blocks representing the deepest invasive front of the primary tumour were used for analysis. A cut-off of 5% positivity was used for dichotomizing the data. The prognostic value was investigated in Cox proportional hazard models for recurrence-free survival (RFS) and overall survival (OS). RESULTS: Overall, 6% of the tumours were classified as high PD-L1. High PD-L1 was related to female gender (p = 0.028), high malignancy grade (< 0.001), right side localization (p < 0.001) and microsatellite instability (MSI) (p < 0.001). Thirty-one (18%) of the MSI and 4 (1%) of the microsatellite stable tumours were classified as high PD-L1, respectively. PD-L1 expression provided no prognostic value as a single marker. In patients with MSI tumours, high PD-L1 expression had no significant impact regarding OS or RFS. CONCLUSIONS: PD-L1 expression in tumour cells of stage II CC did not provide any prognostic impact, neither in the entire population-based cohort nor in the group of MSI patients. Additional investigations of the immunogenic microenvironment are needed for evaluating the prognostic information in CC.

Co-Detection of miR-21 and TNF-α mRNA in Budding Cancer Cells in Colorectal Cancer.

MicroRNA-21 (miR-21) is upregulated in many cancers including colon cancers and is a prognostic indicator of recurrence and poor prognosis. In colon cancers, miR-21 is highly expressed in stromal fibroblastic cells and more weakly in a subset of cancer cells, particularly budding cancer cells. Exploration of the expression of inflammatory markers in colon cancers revealed tumor necrosis factor alpha (TNF-α) mRNA expression at the invasive front of colon cancers. Surprisingly, a majority of the TNF-α mRNA expressing cells were found to be cancer cells and not inflammatory cells. Because miR-21 is positively involved in cell survival and TNF-α promotes necrosis, we found it interesting to analyze the presence of miR-21 in areas of TNF-α mRNA expression at the invasive front of colon cancers. For this purpose, we developed an automated procedure for the co-staining of miR-21, TNF-α mRNA and the cancer cell marker cytokeratin based on analysis of frozen colon cancer tissue samples (n = 4) with evident cancer cell budding. In all four cases, TNF-α mRNA was seen in a small subset of cancer cells at the invasive front. Evaluation of miR-21 and TNF-α mRNA expression was performed on digital slides obtained by confocal slide scanning microscopy. Both co-expression and lack of co-expression with miR-21 in the budding cancer cells was noted, suggesting non-correlated expression. miR-21 was more often seen in cancer cells than TNF-α mRNA. In conclusion, we report that miR-21 is not linked to expression of the pro-inflammatory cytokine TNF-α mRNA, but that miR-21 and TNF-α both take part in the cancer expansion at the invasive front of colon cancers. We hypothesize that miR-21 may protect both fibroblasts and cancer cells from cell death directed by TNF-α paracrine and autocrine activity.

Prognostic impact of CDX2 in stage II colon cancer: results from two nationwide cohorts.

BACKGROUND: The aim of the present study was to validate the prognostic impact of CDX2 in patients with stage II colon cancer. METHODS: Two unbiased population-based cohorts representing all patients operated for stage II colon cancer in Denmark in 2002 and 2003. The CDX2 expression was evaluated by immunohistochemistry on whole tumour sections. Patients were classified into three groups, CDX2-positive, -moderate, and -negative, for comparison with the clinical data. RESULTS: A total of 1157 patients were included. We found a significant relationship between loss of CDX2 expression and poor disease-free survival in both cohorts, p = 0.0267 and 0.0118, respectively. Five-year disease-free survival rates were 66%, 72% and 74% in the first cohort and 62%, 65%, and 75% in the second cohort for the negative, moderate, and positive CDX2 expression groups, respectively. Multiple Cox regression analysis performed on the combined cohorts confirmed an independent prognostic impact of CDX2 on disease-free survival, hazard ratio 1.543 (95% confidence interval 1.129-2.108), p = 0.0065. CONCLUSIONS: This retrospective study provides validation regarding the prognostic impact of CDX2 in patients with stage II colon cancer. The results justify prospective validation clarifying its clinical impact.

Tumor-stroma ratio predicts recurrence in patients with colon cancer treated with neoadjuvant chemotherapy.

BACKGROUND: Neoadjuvant chemotherapy represents a new treatment approach to locally advanced colon cancer. The aim of this study was to analyze the ability of tumor-stroma ratio (TSR) to predict disease recurrence in patients with locally advanced colon cancer treated with neoadjuvant chemotherapy. MATERIAL AND METHODS: This study included 65 patients with colon cancer treated with neoadjuvant chemotherapy in a phase II trial. All patients were planned for three cycles of capecitabine and oxaliplatin before surgery. Hematoxylin and eosin stained tissue sections from surgically resected primary tumors were sampled and analyzed by conventional microscopy. Patients were divided into stroma-high (>50%, i.e. TSR low) and stroma-low (≤50%, i.e. TSR high) for the comparison with clinical data. RESULTS: A low TSR was found in 47% of the surgically resected primary tumors and correlated to a significantly higher T- and N-category compared, to tumors with a high TSR (p < .01). A low TSR was also significantly associated with disease recurrence (p = .008), translating into significant differences in disease free survival (DFS) and overall survival, p < .002. The 5-year DFS rate for patients with a low TSR was 55%, compared to 94% in the group of patients with a high TSR. CONCLUSIONS: TSR assessed in the surgically resected primary tumor from patients with locally advanced colon cancer treated with neoadjuvant chemotherapy provides prognostic value and may serve as a relevant parameter in selecting patients for post-operative treatment.

The prognostic value of tumour stroma ratio and tumour budding in stage II colon cancer. A nationwide population-based study.

PURPOSE: High-risk patients with stage II colon cancer (CC) may benefit from adjuvant chemotherapy, but additional prognostic markers are needed for better stratification. We investigated the prognostic value of tumour stroma ratio (TSR) and tumour budding (TB). METHODS: A nationwide population-based cohort of 573 patients with stage II CC was included. TSR was scored on hematoxylin and eosin sections as low TSR (> 50% stroma) and high TSR (≤ 50% stroma). TB was evaluated in hotspots on pan-cytokeratin stained sections in 10 high power fields (HPF) at the invasive front and classified by the mean number of buds per HPF as high grade budding (≥ 10 buds) or low-grade budding (< 10 buds). The prognostic value was investigated in Cox proportional hazard models for recurrence-free survival (RFS) and overall survival (OS). RESULTS: Low TSR was associated with worse RFS (HR = 1.342 (95% CI 1.006-1.791), p = 0.045) and OS (HR = 1.376 (95% CI 1.016-1.862), p = 0.039). Furthermore, an association was found between low TSR and microsatellite stabile tumours (p < 0.001). The mean number of buds per HPF was associated to TSR with increasing number of buds related to a lower TSR (p = 0.026). No statistically significant prognostic impact of TB regarding OS or RFS was detected. CONCLUSIONS: TSR provided valuable prognostic information, and adding TSR to the current risk stratification may contribute to better patient selection. The estimates of TSR and TB were found to be associated, but no prognostic value of TB was documented.

Long-term risk of colorectal cancer after negative colonoscopy in a Danish gFOBT screening cohort.

Faecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all screen positive persons have negative colonoscopy, but consensus is lacking on how these persons should be followed up. Health authorities in Denmark and The Netherlands recommend suspending screening for 8-10 years, while patients in UK are invited to screening after 2 years. In this cohort-study, we followed 166,277 individuals invited to FOBT-screening in 2005-2006 and a reference group comprising the remaining 1,240,348 Danes of the same age. We linked Danish population and health service registers to obtain information about colonoscopy outcome and incident CRC. We estimated CRC risk by colonoscopy outcome (adenoma, other colorectal pathology or negative colonoscopy) for the reference group, the screening group, and subgroups. Persons with positive screening FOBT followed by negative colonoscopy had the same long-term CRC risk as persons with adenoma detected due to a positive screening FOBT (aHR 1.33, 95% CI: 0.65-2.71). We found no difference in the long-term CRC risk between persons with negative colonoscopy after a positive FOBT screening test and the unscreened reference population (aHR 1.05, 95% CI: 0.62-1.78). Since FOBT screen positive persons in our study remained at average risk of CRC despite of a negative index colonoscopy, we question the safety of suspending FOBT screening for this group. It needs to be monitored whether recent efforts to improve colonoscopy quality have been successful in ensuring low CRC risk after negative colonoscopy also in FOBT positive persons.

High-dose chemoradiotherapy and watchful waiting for distal rectal cancer: a prospective observational study.

BACKGROUND: Abdominoperineal resection is the standard treatment for patients with distal T2 or T3 rectal cancers; however, the procedure is extensive and mutilating, and alternative treatment strategies are being investigated. We did a prospective observational trial to assess whether high-dose radiotherapy with concomitant chemotherapy followed by observation (watchful waiting) was successful for non-surgical management of low rectal cancer. METHODS: Patients with primary, resectable, T2 or T3, N0-N1 adenocarcinoma in the lower 6 cm of the rectum were given chemoradiotherapy (60 Gy in 30 fractions to tumour, 50 Gy in 30 fractions to elective lymph node volumes, 5 Gy endorectal brachytherapy boost, and oral tegafur-uracil 300 mg/m(2)) every weekday for 6 weeks. Endoscopies and biopsies of the tumour were done at baseline, throughout the course of treatment (weeks 2, 4, and 6), and 6 weeks after the end of treatment. We allocated patients with complete clinical tumour regression, negative tumour site biopsies, and no nodal or distant metastases on CT and MRI 6 weeks after treatment to the observation group (watchful waiting). We referred all other patients to standard surgery. Patients under observation were followed up closely with endoscopies and selected-site biopsies, with surgical resection given for local recurrence. The primary endpoint was local tumour recurrence 1 year after allocation to the observation group. This study is registered with ClinicalTrials.gov, number NCT00952926. Enrolment is closed, but follow-up continues for secondary endpoints. FINDINGS: Between Oct 20, 2009, and Dec 23, 2013, we enrolled 55 patients. Patients were recruited from three surgical units throughout Denmark and treated in one tertiary cancer centre (Vejle Hospital, Vejle, Denmark). Of 51 patients who were eligible, 40 had clinical complete response and were allocated to observation. Median follow-up for local recurrence in the observation group was 23·9 months (IQR 15·3-31·0). Local recurrence in the observation group at 1 year was 15·5% (95% CI 3·3-26·3). The most common acute grade 3 adverse event during treatment was diarrhoea, which affected four (8%) of 51 patients. Sphincter function in the observation group was excellent, with 18 (72%) of 25 patients at 1 year and 11 (69%) of 16 patients at 2 years reporting no faecal incontinence at all and a median Jorge-Wexner score of 0 (IQR 0-0) at all timepoints. The most common late toxicity was bleeding from the rectal mucosa; grade 3 bleeding was reported in two (7%) in 30 patients at 1 year and one (6%) of 17 patients at 2 years. There were no unexpected serious adverse reactions or treatment-related deaths. INTERPRETATION: High-dose chemoradiotherapy and watchful waiting might be a safe alternative to abdominoperineal resection for patients with distal rectal cancer. FUNDING: CIRRO-The Lundbeck Foundation Center for Interventional Research in Radiation Oncology and The Danish Council for Strategic Research.

Neoadjuvant chemotherapy in locally advanced colon cancer. A phase II trial.

BACKGROUND: Neoadjuvant chemotherapy has proven valuable in several tumors, but it has not been elucidated in colon cancer. The present phase II trial addressed the issue in high-risk patients selected by computed tomography (CT) scan. MATERIAL AND METHODS: Patients with resectable colon cancer fulfilling the following criteria were offered inclusion; Histopathological verification of adenocarcinoma, T3 tumor on CT scan with extramural tumor invasion > 5 mm or T4 tumor, age ≥ 18 years, PS ≤ 2, adequate hematology, and informed consent. Patients with KRAS, BRAF or PIK3CA mutation or unknown mutational status received three cycles of capecitabine 2000 mg/m(2) days 1-14 q3w and oxaliplatin 130 mg iv day 1 q3w. Wild-type patients received the same chemotherapy supplemented with panitumumab 9 mg/kg iv q3w. After the operation, patients fulfilling the international criteria for adjuvant chemotherapy, i.e. high-risk stage II and III patients, received five cycles of the same chemotherapy without panitumumab. Patients not fulfilling the criteria were offered follow-up only. The primary endpoint was the fraction of patients not fulfilling the criteria for adjuvant chemotherapy (converted patients). Secondary endpoints were recurrence rate, disease-free survival (DFS), and toxicity. RESULTS: The study included 77 patients. The conversion rate was 42% in the wild-type group compared to 51% in patients with a mutation. The cumulative recurrence rate in converted versus unconverted patients was 6% versus 32% (p = 0.005) translating into a three-year DFS of 94% versus 63% (p = 0.005). CONCLUSION: Neoadjuvant chemotherapy in colon cancer is feasible and the results suggest that a major part of the patients can be spared adjuvant chemotherapy. Validation in a randomized trial is warranted.

The prognostic value of microRNA-126 and microvessel density in patients with stage II colon cancer: results from a population cohort.

BACKGROUND: Angiogenesis plays a pivotal role in malignant tumour growth and the metastatic process. We analysed the prognostic value of two angiogenesis parameters, microRNA-126 (miRNA-126) and microvessel density (MVD), in a population based cohort of patients operated for stage II colon cancer. METHODS: A total of 560 patients were included. Analyses were performed on formalin fixed paraffin embedded tissue from the primary tumours. The analysis of miRNA-126 expression was performed by qPCR. Microvessels were visualised by CD105 and quantified in hot spots using a light microscope. The analyses were correlated with recurrence-free cancer specific survival (RF-CSS) and overall survival (OS). RESULTS: Low miRNA-126 expression was significantly correlated to T4, high malignancy grade, tumour perforation, fixation, and the presence of microsatellite instability. A prognostic impact on OS was detected in the simple analysis favouring patients with high miRNA-126 expression p = 0.03, and borderline significance as to RF-CSS, p = 0.08. The impact on OS demonstrated borderline significance in a following multiple Cox regression analysis, hazard ratio 0.76 (95% confidence interval, 0.58-1.00), p = 0.051. The MVD estimate was not associated with either RF-CSS, p = 0.49, or OS, p = 0.94. CONCLUSION: The current population based study of patients operated for stage II colon cancer demonstrated correlations between several prognostic unfavourable characteristics and miRNA-126 and argues for a possible prognostic impact on overall survival. An influence on survival by the MVD estimate was not detected.

Selection of colon cancer patients for neoadjuvant chemotherapy by preoperative CT scan.

OBJECTIVE: Preoperative staging is essential to plan correct treatment of colon cancer and calls for objective, accurate methods for the introduction of neoadjuvant chemotherapy, which represents a new treatment option. PURPOSE: To evaluate the diagnostic accuracy of multislice computed tomography (CT) in local staging of colon cancer correlated with histopathological parameters, including criteria for adjuvant chemotherapy. MATERIAL AND METHODS: A total of 74 included patients had preoperative CT scans and surgical resection of their colon tumors. Tumor stage (T-stage), extramural tumor invasion (ETI), nodal stage (N-stage), extramural venous invasion (EVI) and the distance from tumor to nearest retroperitoneal fascia (DRF) were retrospectively assessed on the CT scan and compared blindly with the results of the pathological examination, including evaluation of the criteria for adjuvant chemotherapy. Advanced tumors were defined as T3 with ETI ≥5 mm or T4. RESULTS: Sixty-nine percent of the tumors were correctly T-staged by CT, 7% were overstaged and 24% were understaged. As to correct recognition of ETI on the CT scan, the observer was 73% accurate compared with histology (70% sensitivity (95% CI: 53-82%), 78% specificity (95% CI: 60-90%), 81% positive predictive value (PPV) (95% CI: 63-91%) and 66% negative predictive value (NPV) (95% CI: 49-80%). N-stage, EVI and DRF had poor accuracy: 53%, 53% and 64%. All patients with advanced tumors on CT fulfilled the criteria for adjuvant chemotherapy. Positive predictive value: 100% (95% CI: 88-100%). CONCLUSION: CT has a potential in the preoperative selection of advanced tumors suitable for neoadjuvant chemotherapy without overtreatment of low-risk patients.

A Comparison of Cellular Immune Response and Immunological Biomarkers in Laparoscopic Surgery for Colorectal Cancer and Benign Disorders.

BACKGROUND: Surgical trauma causes immune impairment, but it is largely unknown whether surgery for cancer and benign diseases instigate comparable levels of immune inhibition. Here, we compared the impact of laparoscopic surgery on immunological biomarkers in patients with colorectal cancer (CRC) and ventral hernia (VH). METHODS: Natural Killer cell activity (NKA), leukocyte subsets, and soluble programmed death ligand 1 (sPD-L1) were measured in blood samples collected from CRC (n = 29) and VH (n = 9) patients preoperatively (PREOP) and on postoperative day (POD) 1, 3-6, 2 weeks and 3 months. NKA was evaluated by the NK Vue assay that uses the level of IFNγ as a surrogate marker of NKA. Normal NKA was defined as IFNγ > 250 pg/mL and low NKA was defined as IFNγ < 250 pg/mL. RESULTS: The CRC cohort was classified into either PREOPLOW having preoperative low NKA or PREOPHIGH having preoperative normal NKA. The median NKA of the PREOPLOW subset was only in the normal range in the POD3 months sample, whereas median NKA of the PREOPHIGH subset and the VH cohort were only low in the POD1 sample. While PREOPLOW differed from VH in the PREOP-, POD1-, and POD3-6 samples (P =.0006, P = .0181, and P = .0021), NKA in PREOPHIGH and VH differed in the POD1 samples (P = .0226). There were no apparent differences in the distribution of leukocyte subsets in the perioperative period between the cohorts. CONCLUSION: CRC patients with preoperative normal NKA and VH patients showed the same pattern of recovery in NKA, while the CRC subset with preoperative low NKA seemed to experience prolonged NK cell impairment. As low NKA is associated with recurrence, preoperative level of NKA may identify patients who will benefit from immune-enhancing therapy in the perioperative period.

International Validation of the Immunoscore Biopsy in Patients With Rectal Cancer Managed by a Watch-and-Wait Strategy.

PURPOSE: No biomarker capable of improving selection and monitoring of patients with rectal cancer managed by watch-and-wait (W&W) strategy is currently available. Prognostic performance of the Immunoscore biopsy (ISB) was recently suggested in a preliminary study. METHODS: This international validation study included 249 patients with clinical complete response (cCR) managed by W&W strategy. Intratumoral CD3+ and CD8+ T cells were quantified on pretreatment rectal biopsies by digital pathology and converted to ISB. The primary end point was time to recurrence (TTR; the time from the end of neoadjuvant treatment to the date of local regrowth or distant metastasis). Associations between ISB and outcomes were analyzed by stratified Cox regression adjusted for confounders. Immune status of tumor-draining lymph nodes (n = 161) of 17 additional patients treated by neoadjuvant chemoradiotherapy and surgery was investigated by 3'RNA-Seq and immunofluorescence. RESULTS: Recurrence-free rates at 5 years were 91.3% (82.4%-100.0%), 62.5% (53.2%-73.3%), and 53.1% (42.4%-66.5%) with ISB High, ISB Intermediate, and ISB Low, respectively (hazard ratio [HR; Low v High], 6.51; 95% CI, 1.99 to 21.28; log-rank P = .0004). ISB was also significantly associated with disease-free survival (log-rank P = .0002), and predicted both local regrowth and distant metastasis. In multivariate analysis, ISB was independent of patient age, sex, tumor location, cT stage (T, primary tumor; c, clinical), cN stage (N, regional lymph node; c, clinical), and was the strongest predictor for TTR (HR [ISB High v Low], 6.93; 95% CI, 2.08 to 23.15; P = .0017). The addition of ISB to a clinical-based model significantly improved the prediction of recurrence. Finally, B-cell proliferation and memory in draining lymph nodes was evidenced in the draining lymph nodes of patients with cCR. CONCLUSION: The ISB is validated as a biomarker to predict both local regrowth and distant metastasis, with a gradual scaling of the risk of pejorative outcome.