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List of tumor and plasma variants and their ctDNA detection thresholds

Substantial improvements have been made in the management of metastatic colorectal cancer (mCRC) in the last two decades, but disease monitoring remains underdeveloped. Circulating tumor DNA (ctDNA) is a promising prognostic and predictive biomarker; however, ctDNA as a marker for mCRC patients is not well established, and there is still no consensus about how to utilize it most cost-effectively. In this study, we aim to investigate plasma ctDNA levels as a biomarker for therapeutic response of mCRC patients. We performed next-generation sequencing (NGS) by using a 12-gene panel to identify genetic variants in 136 tumor tissue and ctDNA samples from 32 mCRC patients. Genetic variants were detected in approximately 70% of samples, and there was a high concordance (85%) between tumor tissue and plasma ctDNA. We observed ctDNA changes in 18 follow-up patients, including the emergence of new variants. Changes in ctDNA levels significantly correlated with tumor shrinkage (P = 0.041), and patients with a ctDNA decrease >80% after treatment had a longer progression-free survival compared with patients with a ctDNA decrease of P = 0.015). The objective response rate among patients with a ctDNA decrease of >80% was better than those with a ctDNA decrease P = 0.007). In conclusion, this study demonstrates that monitoring of genetic ctDNA variants can serve as a valuable biomarker for therapeutic efficacy in mCRC patients, and that using a moderate-sized 12-gene NGS panel may be suitable for such clinical monitoring. Mol Cancer Ther; 17(10); 2238–47. ©2018 AACR.

Although cigarette smoking is a well-known risk factor for anastomotic leakage during rectal surgery, the proper duration of smoking cessation that can decrease anastomotic leakage in patients undergoing sphincter-preserving surgery is unclear. This study aimed to investigate the optimal duration of smoking cessation that can reduce this complication.Between January 1, 2000, and December 31, 2012, we enrolled 1246 consecutive patients who underwent curative-intent sphincter-preserving surgery without preventive stoma at the Division of Colorectal Surgery of a tertiary referral center in Taiwan. Questionnaires were used to record their pre-surgical smoking status. The receiver operating characteristic (ROC) curve was used to determine the optimal cut-off duration of smoking cessation. Multivariate analysis was used to verify the effect of cigarette cessation on anastomotic leakage.The ROC curve showed a cut-off value of 10.5 years of cessation duration. Therefore, the former-smoker group was further divided using a cessation duration of 10 years. The overall anastomotic leakage rate was 5.29%. However, the anastomotic leakage rate in current smokers (9.3%) and in those who quit for 10 years (12.9%) was significantly higher than that in non-smokers (3.3%) and those who quit for ≥ 10 years (4.5%). On multivariate analysis, current smokers (p = 0.022), former smokers with 10 years of smoking cessation (OR 2.725; p = 0.029), male sex (p = 0.015), and low rectal cancer (p 0.001) were all independently related to the development of anastomotic leakage.Smoking cessation for 10 years remains a risk factor for anastomotic leakage in patients with mid-to-low rectal cancer undergoing sphincter-preserving surgery.

It is controversial whether patients who achieve clinical complete remission (cCR) of rectal cancer should be treated with the “watch and wait” (W&W) or radical resection (RR) strategy. Our study aimed to compare the survival outcomes and ostomy rate of the W&W and RR strategies. Between January 2008 and December 2015, we investigated 26 patients who achieved pathologic complete remission after undergoing RR and 36 patients who adopted the W&W strategy because of cCR. The tumor regrowth, salvage surgery, recurrence, disease-free, and overall survival (OS) rates were assessed. In our study, recurrences occurred in nine and two patients from the W&W and RR groups, respectively. Each patient in the RR group had a temporary or permanent ostomy, but only three (8.3%) had an ostomy in the W&W group. The 5-year recurrence rate was 25.0% in the W&W group and 7.7% in the RR group. Six patients (16.7%) had tumor regrowth in the W&W group, and all were resectable when regrowth. The 5-year OS rates between the two groups were nonsignificant. There is no specific risk factor for recurrence and OS. Under close surveillance, the W&W group achieved similar OS to the RR group and benefited from a lower ostomy rate.

Substantial improvements have been made in the management of metastatic colorectal cancer (mCRC) in the last two decades, but disease monitoring remains underdeveloped. Circulating tumor DNA (ctDNA) is a promising prognostic and predictive biomarker; however, ctDNA as a marker for mCRC patients is not well established, and there is still no consensus about how to utilize it most cost-effectively. In this study, we aim to investigate plasma ctDNA levels as a biomarker for therapeutic response of mCRC patients. We performed next-generation sequencing (NGS) by using a 12-gene panel to identify genetic variants in 136 tumor tissue and ctDNA samples from 32 mCRC patients. Genetic variants were detected in approximately 70% of samples, and there was a high concordance (85%) between tumor tissue and plasma ctDNA. We observed ctDNA changes in 18 follow-up patients, including the emergence of new variants. Changes in ctDNA levels significantly correlated with tumor shrinkage (P = 0.041), and patients with a ctDNA decrease >80% after treatment had a longer progression-free survival compared with patients with a ctDNA decrease of 80% was better than those with a ctDNA decrease

Background: The neutrophil-to-lymphocyte ratio is a significant prognostic marker in resectable colorectal cancer; however, there are no equivalent findings for perforated colon cancer. Using our colorectal cancer database, we retrospectively analyzed the data from 1995 to 2015 to determine whether the preoperative neutrophil-to-lymphocyte ratio is associated with survival outcomes in patients with perforated colon cancer.Methods: One-to-one propensity score matching was applied to minimize the difference between the high (>5) and low (≤5) neutrophil-to-lymphocyte ratio groups. Clinicopathological factors, long-term overall survival, and disease-free survival were analyzed and compared between the two groups. The primary outcomes were overall survival and disease-free survival.Results: Before propensity score matching, the high neutrophil-to-lymphocyte ratio group had a significantly higher prevalence of leukocytosis (low vs. high neutrophil-to-lymphocyte ratio groups: 12 [12.9%] vs. 46 [59.7%], pvs. high neutrophil-to-lymphocyte ratio groups: 30 [32.3%] vs. 42 [54.5%], p=0.003), and a higher emergent operation rate (low vs. high neutrophil-to-lymphocyte ratio groups: 5 [5.4%] vs. 20 [26.0%], pConclusions: The neutrophil-to-lymphocyte ratio has limited predictive value for determining outcomes in patients with perforated colon cancer.

The impact of immune cells (ICs) expressing various markers remains poorly understood in nonmetastatic colorectal cancer patients who have undergone colectomy. Here, we aimed to clarify the correlation between IC density and clinical parameters and survival. Programmed death protein-1 (PD-1), programmed cell death protein ligand-1 (PD-L1), clusters of differentiation (CD)-3, CD-8, and CD45RO immunostaining was performed for 421 patients using tissue microarray and automatic counting. Tumor stroma area immune density was assessed in comparison to clinical histological factors and surgical outcomes. High-density CD-8 expression was significantly associated with current smoking habits or a smoking history (P = .006). High-density of PD-1 expression was correlated with Lynch syndrome patients (P

Background: The neutrophil-to-lymphocyte ratio is a significant prognostic marker in resectable colorectal cancer; however, there are no equivalent findings for perforated colon cancer. Using our colorectal cancer database, we retrospectively analyzed the data from 1995 to 2015 to determine whether the preoperative neutrophil-to-lymphocyte ratio is associated with survival outcomes in patients with perforated colon cancer.Methods: One-to-one propensity score matching was applied to minimize the difference between the high (>5) and low (≤5) neutrophil-to-lymphocyte ratio groups. Clinicopathological factors, long-term overall survival, and disease-free survival were analyzed and compared between the two groups. The primary outcomes were overall survival and disease-free survival.Results: Before propensity score matching, the high neutrophil-to-lymphocyte ratio group had a significantly higher prevalence of leukocytosis (low vs. high neutrophil-to-lymphocyte ratio groups: 12 [12.9%] vs. 46 [59.7%], pvs. high neutrophil-to-lymphocyte ratio groups: 30 [32.3%] vs. 42 [54.5%], p=0.003), and a higher emergent operation rate (low vs. high neutrophil-to-lymphocyte ratio groups: 5 [5.4%] vs. 20 [26.0%], pConclusions: The neutrophil-to-lymphocyte ratio has limited predictive value for determining outcomes in patients with perforated colon cancer.

Background Colorectal cancer (CRC) is a major health concern globally, but exhibits regional and/or environmental distinctions in terms of outcome especially for patients with stage III CRC. Methods From 2014 to 2016, matched pairs of tumor and adjacent normal tissue samples from 60 patients with stage I–IV CRC Chang Gung Memorial Hospital in Taiwan were analyzed using next-generation sequencing. The DNA, mRNA, and miRNA sequences of paired tumor tissues were profiled. An observational study with survival analysis was done. Online datasets of The Cancer Genome Atlas (TCGA) and The International Cancer Genome Consortium (ICGC) were also integrated and compared. Results The gene that exhibited the highest mutation rate was adenomatous polyposis coli (APC) (75.0%), followed by TP53 (70.0%), KRAS (56.6%), and TTN (48.3%). APC was also the most frequently mutated gene in TCGA and ICGC datasets. Surprisingly, for non-metastatic cases (stages I-III), CRC patients with mutated APC had better outcome in terms of overall survival (p = 0.041) and recurrence free survival (p = 0.0048). Particularly for stage III CRC, the overall survival rate was 94.4% and 67.7%, respectively (p = 0.018), and the recurrence free survival rate was 94.4% and 16.7%, respectively (p = 0.00044). Further clinical and gene expression analyses revealed that the APC wt specimens to a greater extent exhibit poor differentiation state as well as EGFR upregulation, providing molecular basis for the poor prognosis of these patients. Finally, based on integrated transcriptome analysis, we constructed the mRNA-miRNA networks underlying disease recurrence of the stage III CRC and uncovered potential therapeutic targets for this clinical condition. Conclusion For stage III CRC, patients with mutated APC had better overall and recurrence free survival.

The purpose of this study was to report the clinicopathological characteristics and treatment outcomes of 45 rectal cancer patients who have a history of cervical cancer with or without remote radiotherapy. Twenty-nine patients (64.4%) with a history of cervical cancer treated with pelvic radiotherapy were classified as group A, 16 (35.6%) patients with a history of cervical cancer not treated with radiotherapy were classified as group B. The median duration between radiotherapy for cervical cancer and rectal adenocarcinoma diagnosis was 18 years. At the time of rectal cancer diagnosis, 5 (17.2%) patients presented stage I disease, 15 (51.7%) had stage II, 1 (3.4%) had stage III, and 8 (27.6%) had stage IV. The patients in group A had older age, higher rates of gross ulcerative lesions, low hemoglobin levels, and a lower rate of lymph node metastases. The patients with secondary rectal cancer developed after radiotherapy for cervical cancer usually presented with abnormal abdominal symptoms, such as proctitis, cystitis, or rectal fistula. Higher colostomy rate was found in this group of patients due to severe pelvic fibrosis or proctitis.

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. While both genetic and environmental factors have been linked to the incidence and mortality associated with CRC, an ethnic aspect of its etiology has also emerged. Since previous large-scale cancer genomics studies are mostly based on samples of European ancestry, the patterns of clinical events and associated mechanisms in other minority ethnic patients suffering from CRC are largely unexplored. We collected 104 paired and adjacent normal tissue and CRC tumor samples from Taiwanese patients and employed an integrated approach – paired expression profiles of mRNAs and microRNAs (miRNAs) combined with transcriptome-wide network analyses – to catalog the molecular signatures of this regional cohort. On the basis of this dataset, which is the largest ever reported for this type of systems analysis, we made the following key discoveries: (1) In comparison to the The Cancer Genome Atlas (TCGA) data, the Taiwanese CRC tumors show similar perturbations in expressed genes but a distinct enrichment in metastasis-associated pathways. (2) Recurrent as well as novel CRC-associated gene fusions were identified based on the sequencing data. (3) Cancer subtype classification using existing tools reveals a comparable distribution of tumor subtypes between Taiwanese cohort and TCGA datasets; however, this similarity in molecular attributes did not translate into the predicted subtype-related clinical outcomes (i.e., death event). (4) To further elucidate the molecular basis of CRC prognosis, we developed a new stratification strategy based on miRNA–mRNA-associated subtyping (MMAS) and consequently showed that repressed WNT signaling activity is associated with poor prognosis in Taiwanese CRC. In summary, our findings of distinct, hitherto unreported biosignatures underscore the heterogeneity of CRC tumorigenesis, support our hypothesis of an ethnic basis of disease, and provide prospects for translational medicine.

Background Local excision (LE) is a feasible treatment approach for rectal cancers in stage pT1 and presents low pathological risk, whereas total mesorectal excision (TME) is a reasonable treatment for more advanced cancers. On the basis of the pathology findings, surgeons may suggest TME for patients receiving LE. This study compared the survival outcomes between LE with/without chemoradiation and TME in mid and low rectal cancer patients in stage pT1/pT2, with highly selective intermediate pathological risk. Methods This retrospective study included 134 patients who received TME and 39 patients who underwent LE for the treatment of intermediate risk (pT1 with poor differentiation, lymphovascular invasion, perineural invasion, relatively large tumor, or small-sized pT2 tumor) rectal cancer between 1998 and 2016. Results Overall survival (OS), disease-free survival (DFS), and cumulative recurrence rate (CRR) were similar between the LE (3-year DFS 92%) and TME (3-year DFS 91%) groups. Following subgrouping into an LE with adjuvant therapy group and a TME without adjuvant therapy group, the compared survival outcomes (OS, DFS, and CRR) were found not to be statistically different. The temporary and permanent ostomy rates were higher in the TME group than in the LE group (p < 0.001). Rates of early and late morbidity following surgery were higher in the TME group (p = 0.005), and LE had similar survival compared with TME. Conclusion For patients who had mid and low rectal cancer in stage pT1/pT2 and intermediate pathological risk, LE with chemoradiation presents an alternative treatment option for selected patients.

The prediction of tumor in the TNM staging (tumor, node, and metastasis) stage of colon cancer using the most influential histopathology parameters and to predict the five years disease-free survival (DFS) period using machine learning (ML) in clinical research have been studied here. From the colorectal cancer (CRC) registry of Chang Gung Memorial Hospital, Linkou, Taiwan, 4021 patients were selected for the analysis. Various ML algorithms were applied for the tumor stage prediction of the colon cancer by considering the Tumor Aggression Score (TAS) as a prognostic factor. Performances of different ML algorithms were evaluated using five-fold cross-validation, which is an effective way of the model validation. The accuracy achieved by the algorithms taking both cases of standard TNM staging and TNM staging with the Tumor Aggression Score was determined. It was observed that the Random Forest model achieved an F-measure of 0.89, when the Tumor Aggression Score was considered as an attribute along with the standard attributes normally used for the TNM stage prediction. We also found that the Random Forest algorithm outperformed all other algorithms, with an accuracy of approximately 84% and an area under the curve (AUC) of 0.82 &plusmn, 0.10 for predicting the five years DFS.

Clinicopathologic factors relating to developing metachronous colorectal cancer (CRC) have been reported. However, the effects of different diagnostic intervals on these risk factors required further analysis. This retrospective study comprised 14,481 patients diagnosed from January 1995 to December 2012. Metachronous CRC was defined as the occurrence of a second colorectal cancer at least 1 year post-operatively. A total of 153 (1.06%) patients developed metachronous CRCs during the follow-up. Significantly higher rates of developing metachronous cancer occurred in male patients (1.2 vs 0.9%), patients with synchronous CRC (2.0 vs 1.0%), and patients with a positive family history of CRC (1.4 vs 0.9%). Pertaining to diagnostic intervals related to clinicopathological features, more severe staging was significant in the diagnostic interval between 2 and 3 years (35 vs 7.7%, 20.6%, 17.5%, P = .01) compared with other intervals. Male patients were more frequently detected to have CRC within 3 years compared with females (53.1 vs 29.1%, P = .005). For a diagnostic interval ≧ 5 years, a significantly higher rate of metachronous CRC located at the right colon was observed than that located at the left colon (36.6 vs 19.7%, p = 0.03). We evinced that a diagnostic interval between 2 and 3 years was a key time for metachronous CRC diagnosis with worse staging distribution. Based on current findings, we recommend the stratification of metachronous CRCs into diagnostic intervals of 1–2, 2–3, and ≧ 3 years, as they exhibit significantly different characteristics.

(1) Background: The aim of this study was to develop a prediction model for assessing individual mPC risk in patients with pT4 colon cancer. Methods: A total of 2003 patients with pT4 colon cancer undergoing R0 resection were categorized into the training or testing set. Based on the training set, 2044 Cox prediction models were developed. Next, models with the maximal C-index and minimal prediction error were selected. The final model was then validated based on the testing set using a time-dependent area under the curve and Brier score, and a scoring system was developed. Patients were stratified into the high- or low-risk group by their risk score, with the cut-off points determined by a classification and regression tree (CART). (2) Results: The five candidate predictors were tumor location, preoperative carcinoembryonic antigen value, histologic type, T stage and nodal stage. Based on the CART, patients were categorized into the low-risk or high-risk groups. The model has high predictive accuracy (prediction error ≤5%) and good discrimination ability (area under the curve &gt, 0.7). (3) Conclusions: The prediction model quantifies individual risk and is feasible for selecting patients with pT4 colon cancer who are at high risk of developing mPC.

Routine postoperative surveillance is recommended for the patients with colorectal cancer (CRC). This study aimed to clarify the conditions indicate initial suspicion of CRC recurrence in different preoperative serum carcinoembryonic antigen (CEA) level groups, including positive physical signs/symptoms, elevated CEA level, positive radiologic studies results, and other elevated tumor markers.A total of 2268 patients with recurrence after curative surgery for CRC were enrolled in this study. The patients were classified into 3 groups according to preoperative serum CEA level (low

Liver resection (LR) is the standard procedure for treating colorectal cancer (CRC) hepatic metastasis; however, LR associated with a high recurrence incidence. This study aimed to determine an optimal post-LR adjuvant chemotherapeutic strategy to improve overall long-term patient outcomes. A retrospective study of 490 patients who had undergone curative LR for CRC hepatic metastasis was performed. Patients who underwent post-LR adjuvant chemotherapy demonstrated high overall survival (OS) rates (hazard ratio [HR] = 0.58, P = .002) but not high recurrence-free survival (RFS) rates (HR = 1.02, P = .885). Moreover, OS was significantly longer in patients who underwent 5-fluorouracil + leucovorin (5-FU/LV; HR = 0.63, P = .039), oxaliplatin-based chemotherapy (HR = 0.45, P

The rate of postoperative morbidity and mortality is reportedly high in patients aged ≥ 75 years with colorectal cancer (CRC). In such patients, a comparison of the short-term outcome between open method and laparoscopy has not been clearly defined in Taiwan. We aimed to compare postoperative morbidity and mortality parameters after open method and laparoscopy in CRC patients aged ≥ 75 years. We retrospectively analyzed patients who underwent surgery for CRC from February 2009 to September 2015 at the Linkou Chang Gung Memorial Hospital in Taiwan and analyzed their clinicopathological factors. Postoperative morbidity and mortality were analyzed for evaluating if laparoscopic surgery offers more favorable outcomes than open surgery in the elderly. A total of 1133 patients were enrolled and analyzed in this study; they were divided into two groups (open method vs. laparoscopy = 797 vs. 336). The anastomotic leakage rate was significantly higher in the laparoscopy group than in the open method group (3.3 vs. 0.9%, p = 0.003). Overall postoperative morbidity and mortality rates showed no significant difference between these two groups. Postoperative hospital stay was significantly shorter in the laparoscopy group than in the open method group (10.4 ± 8.7 vs. 13.8 ± 13.5 days, p

Background The preoperative carcinoembryonic antigen (CEA) level as a prognostic factor of colorectal cancer (CRC) has been in debate. Methods A consecutive case series were collected from our database of CRC from 1995 to 2010. Clinicopathological factors were matched by propensity score methods with calliper width of 0.05 and a 1:4 ratio. Long-term overall survival (OS) and disease-specific survival (DSS) were analysed and compared between 3 different serum CEA levels. Results A total number of 9634 patients were included initially. After exclusion and matching, a number of 6099 cases were matched by propensity score matching methods with median follow-up period 86 months. The survival analysis showed poor OS in elevated serum CEA groups than normal CEA level (5 year survival rate: 75% vs. 66% vs. 61%) and was also presented in both subgroups divided by lymph node (LN) stage (LN positive: 69% vs. 56% vs. 50%, LN negative: 83% vs. 77% vs. 72%) but not between elevated groups. In contrast, DSS showed significantly poor outcome between each group and was proportional to serum CEA elevation (5 year survival rate: 83% vs. 76% vs. 69%, p In multivariate Cox regression model after adjusted with TNM stage, smoking, DM, renal insufficiency, liver cirrhosis and other factors, elevated CEA showed higher risk in DSS (5 to 10 ng/ml HR=1.540,>10 ng/ml HR=1.910, both p Conclusions Elevated preoperative serum CEA can be an independent prognostic factor for stage I to III CRC patients after curative resection with poor long-term overall and oncological outcome.

Impaired kidney function is associated with different diseases. However, its impact on colorectal cancer has not been clarified. In order to understand the effect of preoperative kidney function on the outcome of patients with cancer, we analyzed colorectal cancer patients with localized or regional diseases.In total, 3731 stage I to III colorectal cancer (CRC) patients were analyzed in Chang Gung Memorial Hospital. Modification of Diet in Renal Disease (MDRD) formula was used for estimated glomerular filtration rate (eGFR). Receiver operating characteristic (ROC) analysis for kidney function cut-off value; Chi-square method, independent t test, or analysis of variance (ANOVA) method for clinicopathological factors; Kaplan-Meier method for disease-free survival (DFS); Cox proportional hazard model for multivariate analysis.Among colon cancer patients, low eGFR (MDRD70) was associated with more male patients, T2 stage, patients without adjuvant chemotherapy, and patients with elevated creatinine level. Low eGFR is a significant risk factor only for stage III colon cancer (hazard ratio 1.70, 95% CI: 1.28-2.26; P0.001). Furthermore, postoperative adjuvant chemotherapy did not significantly increase 5-year DFS for both high and low eGFR groups in stage II patients (5 yrs DFS, 94.8% vs. 84.1%, P = 0.098 for high eGFR subgroup; and 75.0% vs. 75.8%, P = 0.379 for low eGFR subgroup). However, significant improvement of 5-yrs DFS after chemotherapy was found in low eGFR stage III colon cancer patients (64.7% vs. 39.4%, P0.001 for low eGFR subgroup). In contrast, no significant DFS difference was caused by chemotherapy for high eGFR stage III subgroup (70.5% vs. 63.9%, P = 0.110).Although low eGFR is an independent risk factor for stage III colon cancer. However, the adjuvant chemotherapy impacts on stage III colon cancer patients differently according to eGFR status.

Enumeration of circulating tumor cells (CTCs) has been proven as a prognostic marker for metastatic colorectal cancer (m-CRC) patients. However, the currently available techniques for capturing and enumerating CTCs lack of required sensitivity to be applicable as a prognostic marker for non-metastatic patients as CTCs are even more rare. We have developed a microfluidic device utilizing antibody-conjugated non-fouling coating to eliminate nonspecific binding and to promote the multivalent binding of target cells. We then established the correlation of CTC counts and neoplasm progression through applying this platform to capture and enumerate CTCs in 2 mL of peripheral blood from healthy (n = 27), benign (n = 21), non-metastatic (n = 95), and m-CRC (n = 15) patients. The results showed that the CTC counts progressed from 0, 1, 5, to 36. Importantly, after 2-year follow-up on the non-metastatic CRC patients, we found that those who had ≥5 CTCs were 8 times more likely to develop distant metastasis within one year after curable surgery than those who had

The BRAF V600E mutation is one of the most common mutations implicated in the development of several types of cancer including colorectal cancer (CRC), where it is associated with aggressive disease phenotypes and poor outcomes. The status of the BRAF V600E mutation is frequently determined by direct DNA sequencing. However, no previous study has sought to quantify the BRAF V600E protein in cancer specimens. Here, we evaluated immunoenrichment coupled with two MS-based quantitative techniques, namely multiple reaction monitoring (MRM) and single ion monitoring conjugated accurate inclusion mass screening (SIM-AIMS), to detect and precisely quantify wild-type (WT) and V600E mutant BRAF proteins in DNA sequence-confirmed CRC tissue specimens. WT and V600E BRAF proteins were immunoprecipitated from a CRC cell line (HT-29), and their representative peptides ( 592 IGDFGLATVK 601 and 592 IGDFGLATEK 601 , respectively) were confirmed by LC-MS/MS analysis and then quantified by MRM or SIM-AIMS with spiked stable isotope-labeled peptide standards. Both assays worked well for measuring WT BRAF from different amounts of HT-29 cell lysates, but the MRM assay was more sensitive than SIM-AIMS assay for quantifying lower levels of V600E BRAF. In protein extracts (2 mg) from 11 CRC tissue specimens, the MRM assay could measure WT BRAF in all 11 cases (0.32–1.66 ng) and the V600E BRAF in two cases (0.1–0.13 ng; mutant-to-WT ratio, 0.16–0.17). The SIM-AIMS assay could also detect WT and V600E BRAF in CRC specimens, but the measured levels of both targets were lower than those determined by MRM assay. Collectively, this study provides an effective method to precisely quantify WT and V600E BRAF proteins in complex biological samples using immunoenrichment-coupled targeted MS. Since the V600E BRAF protein has emerged as an important therapeutic target for cancer, the developed assay should facilitate future BRAF-related basic and clinical studies.

Background: The benefit of oxaliplatin as postoperative adjuvant chemotherapy in the real world practice remained further clarified. Clinically, choosing oral 5-FU drug or FOLFOX regimen may depend to drug toxicity and patient’s age and comorbidities. Methods: Patients included in this study was from Chang Gung Memorial Hospital (CGMH) colorectal cancer registry database. Treatment outcomes were compared based on the type of chemotherapy in terms of OS and DFS. Multivariate Cox-regression modelling was used to adjust for the potential confounders. Results: Between 2007 Jan and 2012 Dec, 688 stage III colon cancer patients were collected including fluorouracil-leucovorin plus oxaliplatin (FOLFOX-6) (283 patients), Capecitabine (259 patients), and Tegafur-uracil (146 patients). Patients receiving FOLFOX-6 were significantly younger (mean age 56.5 yrs vs 65,1 yrs and 66,9 yrs ), more poor differentiation (15.9% vs 8.1% and 8.2%), deeper tumor invasion (T4 lesion 25.1% vs 15.8% and 17.1%), more advanced nodal involvement (N2/3 51.9% vs 18.1% and 20.5%) and had less comorbidity (50.2% vs 61.4% and 65.1%). Rate of completeness of chemotherapies (88.0% vs 87.6% and 81.5%) was no significant difference. Treatment outcome, by balancing confounding factors including co-morbidities, multivariate analysis showed that impact on OS in patients receiving FOLFOX-6 regimen was no difference comparing with capecitabine (HR=1.32, p=0.32) while Tegafur-uracil was statistically significant worse than Tegafur (HR=1.69, p=0.03). However, disease free survival (DFS) was no significantly different for FOLFOX-6 (HR 0.97, p=0.88) and Tegafur (HR 1.08, p=0.72) comparing with capecitabine. Conclusions: In this retrospective study, as post-operative adjuvant setting, we found oral chemotherapy (Capecitabine or UFUR) compared with FOLFOX-6 for stage III colon cancer patients demonstrated similar DFS after balancing bias on imbalanced use of oxaliplatin-based chemotherapy.

We evaluated the effect of neutrophil-to-lymphocyte ratio (NLR) on disease-free survival in patients with stages I to III colorectal cancer (CRC).There were 3857 patients identified from our database. We used receiver operating characteristic (ROC) analysis to identify the best cutoff value of NLR. A 5-year disease-free survival was used as end point. Survival analysis was used to assess the NLR effect, after stratification by several clinopathologic factors.In the ROC analysis, NLR = 3 had the highest sensitivity and specificity. Elevated NLR (3) in colon cancer seemed to accompany larger tumor size (~5 cm) and more advanced T stage. By multivariate analysis, elevated NLR in colon cancer was associated with an increased risk of disease progression or cancer death [hazard ratio (HR) 1.377, 95 % confidence interval 1.104-1.717, P = 0.014]. However, elevated NLR in rectal cancer lost its significance in multivariate analysis (HR 1.121, 95 % confidence interval 0.941-1.336, P = 0.200). Patients with elevated NLR had worse outcome, especially for colon cancer.Preoperative NLR influenced the disease-free survival in patients with stages I to III CRC. Elevated NLR (3) was associated with worse outcome (5-year disease-free survival 66.3 % vs. 78.9 % in colon cancer, P 0.001; 60. 5 % vs. 66.2 % in rectal cancer, P = 0.008). The difference was larger in colon cancer than in rectal cancer. NLR should be considered as a prognostic factor for stages I to III CRC patients after curative surgery.

Background. The cancer cell secretome has been recognized as a valuable reservoir for identifying novel serum/plasma biomarkers for different cancers, including colorectal cancer (CRC). This study aimed to verify four CRC cell-secreted proteins (tumor-associated calcium signal transducer 2/trophoblast cell surface antigen 2 (TACSTD2/TROP2), tetraspanin-6 (TSPAN6), bone marrow stromal antigen 2 (BST2), and tumor necrosis factor receptor superfamily member 16 (NGFR)) as potential plasma CRC biomarkers.Methods. The study population comprises 152 CRC patients and 152 controls. Target protein levels in plasma and tissue samples were assessed by ELISA and immunohistochemistry, respectively.Results. Among the four candidate proteins examined by ELISA in a small sample set, only BST2 showed significantly elevated plasma levels in CRC patients versus controls. Immunohistochemical analysis revealed the overexpression of BST2 in CRC tissues, and higher BST2 expression levels correlated with poorer 5-year survival (46.47% versus 65.57%;p=0.044). Further verification confirmed the elevated plasma BST2 levels in CRC patients (2.35 ± 0.13 ng/mL) versus controls (1.04 ± 0.03 ng/mL) (p<0.01), with an area under the ROC curve (AUC) being 0.858 comparable to that of CEA (0.867).Conclusion. BST2, a membrane protein selectively detected in CRC cell secretome, may be a novel plasma biomarker and prognosticator for CRC.

Background Colonic lymphoma is an uncommon presentation of extranodal lymphoma. Colonic mucosa-associated lymphoid tissue lymphoma is a different entity from gastric mucosa-associated lymphoid tissue lymphoma, and very rare. The presentation and management of colonic mucosa-associated lymphoid tissue are highly variable in the literature. Case presentation We report the case of a 59-year-old Taiwanese man who underwent a colonoscopy after a positive test for fecal occult blood. His past history included hypertension and hyperthyroidism. The colonoscopy revealed an adenomatous polyp and mucosa-associated lymphoid tissue lymphoma. We successfully performed a polypectomy and endoscopic mucosal resection. The lymphoma was staged according to the Ann Arbor system modified by Musshoff as E-I. Our patient showed no lymphoma recurrence over a 3-year follow-up. Conclusions Endoscopic mucosal resection for colonic mucosa-associated lymphoid tissue lymphoma without disseminated disease may be feasible. We successfully used colonoscopic treatment without adjuvant therapy to treat early-stage pathogen-free colonic mucosa-associated lymphoid tissue lymphoma.

Background/aims To evaluate outcome and prognostic factors of patients with anorectal melanoma. Methodology Twenty-two consecutive patients with anorectal melanoma received operation from 1993 through 2011 were reviewed. The definitions of stage I, II and III are local disease, locoregional lymphadenopathy and metastatic disease, respectively. Results The patients included 8 men and 14 women, aged from 36 to 83 years (mean, 58.4 years). At the end of the follow-up period, 19 patients died of disease and only 3 patients were alive with disease. Only two patients were alive longer than 5 years after operation. For stage I and II tumors that underwent clinical curative resection (n=17), stage II (p=0.04), tumor size >3 cm (p=0.008) and invasion depth to muscle (p=0.021) all showed poorer prognosis in overall survival. Though wide local excision (WLE) were performed in the patients with earlier tumors, there was no statistical difference in overall (p=0.063) and disease-free survival (p=0.333) between WLE and radical surgery. Furthermore, patients with WLE had more chance of local recurrence than radical surgery (6/7 vs. 3/10, p=0.050). Four salvage radical operations could be performed after local recurrence in WLE group. Conclusions WLE increases the chance of local recurrence more than radical surgery. Care should be taken to avoid microseeding during performed WLE.

Background/aims Long course concurrent chemoradiotherapy provides potential tumor downstaging. When local recurrent rectal cancer without distant metastases is diagnosed, a potentially curative resection can be performed. The aim of this study was to assess the outcome of concurrent chemoradiotherapy in treating isolated local recurrent rectal cancer. Methodology Patients (n=102) with isolated local recurrent rectal cancer within the pelvis were scheduled for concurrent chemoradiotherapy, consisting of pelvic irradiation with a total dose of 50.4 Gy in 28 fractions. Chemotherapy was administered concurrently and included 85 mg/m2 oxaliplatin by venous infusion over 2 h on day 1, followed by 1,200 mg*m-2*day-1 of continuous venous infusion for 2 days. This regimen was repeated every 2 weeks for 6 cycles. The overall survival rate, responses, disease-free interval and toxicities were assessed. Results A total of 96 patients completed planned concurrent chemoradiation. Complete clinical responses were found in 13 of the 96 patients (14%), partial responses in 59 (61%), stable disease in 21 (22%) and disease progression in 3 (3%). The overall survival and disease-free survival rates in all the 96 patients were 45% and 14%, respectively. Conclusions The treatment of locally recurrent rectal cancer is complicated. Concurrent chemoradiation can increase disease-free survival and overall survival by increasing complete resection rate of locally recurrent tumors and even complete response of the tumors. Ongoing treatment strategies aim to enhance response rates and to accurately assess the extent of local recurrent tumor response to concurrent chemoradiation.