Detection and clinical significance of CEACAM5 methylation in colorectal cancer patients.

Colorectal cancer (CRC) is a globally common cancer, and the serum carcinoembryonic antigen (sCEA) is widely applied as a diagnostic and prognostic tumor marker in CRC. This study aimed to elucidate the mechanism of CEA expression and corresponding clinical features to improve prognostic assessments. In CRC cells, hypomethylation of the CEACAM5 promoter enhanced CEA expression in HCT116 and HT29 cells with 5-aza-2'-deoxycytidine (5-Aza-dC) treatment. Our clinical data indicated that 64.7% (101/156) of CRC patients had an sCEA level above the normal range, and 76.2% (77/101) of those patients showed a lower average CpG methylation level of the CEACAM5 promoter. The methylation analysis showed that both CRC cell lines and patient samples shared the same critical methylation CpG regions at -200 to -500 and -1000 to -1400 bp of the CEACAM5 promoter. Patients with hypermethylation of the CEACAM5 promoter showed features of a BRAF mutation, TGFB2 mutation, microsatellite instability-high, and preference for right-sided colorectal cancer and peritoneal seeding presentation that had a similar clinical character to the consensus molecular subtype 1 (CMS1) of colorectal cancer. Additionally, hypermethylation of the CEACAM5 promoter combined with evaluated sCEA demonstrated the worst survival among the patients. Therefore, the methylation status of the CEACAM5 promoter also served as an effective biomarker for assessing disease prognosis. Results indicated that DNA methylation is a major regulatory mechanism for CEA expression in colorectal cancer. Moreover, our data also highlighted that patients in a subgroup who escaped from inactivation by DNA methylation had distinct clinical and pathological features and the worst survival.

The Negative Prognostic Impact of Lymph Node Skip Metastasis in Stage III Colon Cancer With pN1 Disease: A Single-Center and Retrospective Cohort Study.

BACKGROUND: Lymph node skip metastasis is a subgroup of lymph node metastatic patterns with low incidence in node-positive colon cancer. Its clinical significance is still unclear. OBJECTIVE: This study aimed to investigate the prognostic impact of lymph node skip metastasis in stage III colon cancer. DESIGN: This is a retrospective observational analysis. SETTINGS: The study was conducted at the Taipei Veterans General Hospital. PATIENTS: This study included patients with stage III colon cancer who underwent D3 lymphadenectomy between 2006 and 2015. MAIN OUTCOME MEASURES: The patients were divided into a lymph node skip metastasis-positive group and a negative group. Recurrence-free survival and overall survival were compared using Kaplan-Meier curves and log-rank test. Cox regression was applied to identify related risk factors influencing survival. RESULTS: A total of 461 patients were reviewed, and lymph node skip metastasis-positive patients represented 13.2% of our sample. Patients with lymph node skip metastasis tended to present with a higher proportion of right-sided cancer, lower positive lymph nodes, lower lymph node ratio, and higher mean BMI. Liver recurrence was more prevalent in the lymph node skip metastasis group ( p = 0.028) than in the negative group. The presence of lymph node skip metastasis was a negative prognostic factor for 5-year recurrence-free survival (51.4% vs 68.7%; p = 0.002) and 5-year overall survival (66.4% vs 80.4%; p = 0.024) in Kaplan-Meier curves and multivariate Cox regression. Subgroup analysis revealed the survival significance of recurrence-free survival ( p = 0.001) and overall survival ( p = 0.011) in lymph node skip metastasis with pN1 disease. LIMITATIONS: This study was limited by its retrospective design, single-center nature, and sampling error. CONCLUSIONS: Lymph node skip metastasis is an independent negative prognostic factor in stage III colon cancer with pN1 disease. More intensive surveillance may be necessary for patients of this subgroup. See Video Abstract at https://links.lww.com/DCR/C60 . IMPACTO PRONSTICO NEGATIVO DE LAS METSTASIS DISCONTNUAS GANGLIONARES LINFTICAS EN CASOS DE CNCER DE COLON ESTADIO III CON ENFERMEDAD PN ESTUDIO DE COHORTES RETROSPECTIVO MONOCENTRICO: ANTECEDENTES:Las metástasis discontínuas ganglionares linfáticas, son un subgrupo de patrones metastásicos en los ganglios linfáticos con baja incidencia en el cáncer de colon con nódulos positivos. Su significado clínico aún no está claro.OBJETIVO:Estudio que tiene por objetivo el investigar el impacto pronóstico de las metástasis discontínuas de los ganglios linfáticos en el cáncer de colon de estadio III.DISEÑO:Análisis observacional retrospectivo.AJUSTES:El estudio se realizó en el Hospital General de Veteranos de Taipei.PACIENTES:Pacientes con cáncer de colon en estadio III que se sometieron a linfadenectomía D3 entre 2006 y 2015.PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes se dividieron en un grupo positivo de metástasis discontínuas en los ganglios linfáticos y un otro grupo negativo. La sobrevida libre de recidiva y la sobrevida global, fueron comparadas mediante las curvas de Kaplan-Meier y la prueba de rango logarítmico. Se aplicó la regresión de Cox para identificar los factores de riesgo relacionados que influyeron en la sobrevida.RESULTADOS:Se revisaron un total de 461 casos, donde los pacientes positivos con metástasis en los ganglios linfáticos representaron el 13,2% de nuestra muestra. Los pacientes con metástasis discontínuas ganglionares linfáticas tendían a presentar una mayor proporción de cáncer localizado en el lado derecho del colon, presentar un menor numéro de ganglios linfáticos positivos y una proporción menor de ganglios linfáticos con un IMC promedio más alto. Las recidivas hepáticas fueron más prevalentes en el grupo de metástasis discontínuas ganglionares linfáticas ( p = 0,028) que en el grupo negativo. La presencia de metástasis discontínuas ganglionares linfáticas fué un factor de pronóstico negativo en la sobrevida libre de recidiva a 5 años (51,4% frente a 68,7%, p = 0,002) y la sobrevida general a 5 años (66,4% frente a 80,4%, p = 0,024) evaluada por las curvas de Kaplan-Meier y la regresión multivariada de Cox. El análisis de subgrupos reveló la importancia de la sobrevida libre de recidiva ( p = 0,001) y la sobrevida general ( p = 0,011) en los casos con metástasis discontínuas ganglionares linfáticas con enfermedad pN1.LIMITACIONES:Diseño retrospectivo, naturaleza de centro único y error de muestreo.CONCLUSIONES:Las metástasis discontínuas ganglionares linfáticas son un factor pronóstico negativo independiente en los casos de cáncer de colon estadio III con enfermedad pN1. Tal vez sea necesaria una mayor vigilancia de los pacientes en este subgrupo.Consulte Video Resumen en https://links.lww.com/DCR/C60 . (Traducción-Dr. Xavier Delgadillo ).

Clinical outcome of local treatment and radical resection for pT1 rectal cancer.

BACKGROUND: Rectal cancer is mainly cured by radical resection with neoadjuvant chemoradiation or adjuvant chemotherapy. Pathological T1 lesions can be managed by local treatment and radiotherapy thereafter. Lower morbidity is the key benefit of these local treatments. Since nodal metastasis is important for staging, radical resection (RR) is suggested. Rectal cancer has higher surgical morbidity than colon cancer; local treatment has been the preferred choice by patients. METHODS: We retrospectively enrolled data of 244 patients with pT1 rectal adenocarcinoma. A total of 202 patients (82.8%) underwent RR, including low anterior resection (LAR) and abdomino-perineal resection (APR), and 42 patients (17.2%) underwent LT, including transanal excision and colonoscopic polypectomy. RESULTS: In our study, seven patients (16.7%) had loco-regional recurrence and distant metastasis from the LT group while eight patients (4.0%) had distant metastasis without loco-regional recurrence from the RR group. The lymph node metastasis rate in RR group was 8.4%. Forty-seven patients (24.2%) underwent LAR with temporary stoma, and its reversal rate was 100%. In the RR group, postoperative complication rate was 10.4% with a mortality rate of 0.5%. Recurrence-free survival (RFS) was 95.7% for RR and 80.2% for LT (P = 0.001), and overall survival (OS) was 93.7% for RR and 70.0% for LT (P = 0.001). CONCLUSION: This study found that RFS and OS in patients of pT1 rectal adenocarcinoma that had received RR were better than receiving LT. Further adjuvant chemotherapy was possible for some RR patients. A higher recurrence rate after LT must be balanced against the morbidity and mortality associated with RR.

Three-dimensional versus conventional two-dimensional laparoscopic colectomy for colon cancer: A 3-year follow-up study.

Background: Three-dimensional (3D) laparoscopy was developed to overcome the drawbacks of two-dimensional (2D) laparoscopy, namely lack of depth perception. However, the benefit of 3D laparoscopy in colorectal surgery is inconclusive. Here, we compare the 3-year follow-up outcomes of 3D and 2D laparoscopic colectomy. Patients and Methods: A total of 91 consecutive patients who underwent either 3D or 2D laparoscopy colectomy from October 2015 to November 2017 by a single surgical team for colon cancer were enrolled. Data were collected from a prospectively constructed database, including clinico-pathological features and operative parameters. The pathological results, recurrence, survival and systemic treatment were collected from the Taiwan Cancer Database. Results: There were 47 patients in the 3D group and 44 in the 2D group. There were no significant differences in characteristics of patients, operation data, pathological results, complications, operative time, blood loss or the number of lymph node harvested between the two groups. In addition, disease-free survival and overall survival were equal between the two groups. Conclusions: This is the first long-term result of a 3D laparoscopic colectomy. In our 3-year follow-up, there was no difference in long-term outcomes between 2D and 3D laparoscopy for colorectal surgery in an experienced centre.

The efficacy of anti-EGFR therapy in treating metastatic colorectal cancer differs between the middle/low rectum and the left-sided colon.

BACKGROUND: Clinically, metastatic rectal cancer has been considered a subset of left-sided colon cancer. However, heterogeneity has been proposed to exist between high and middle/low rectal cancers. We aimed to examine the efficacy of anti-epidermal growth factor receptor (EGFR) treatment for middle/low rectal and left-sided colon cancers. METHODS: This study enrolled 609 patients with metastatic colorectal cancer who were treated with anti-EGFR therapy. They were divided into groups based on primary tumour locations: the right-sided colon, the left-sided colon or the middle/low rectum. The efficacy of first-line and non-first-line anti-EGFR treatment was analysed. Genomic differences in colorectal cancer data from The Cancer Genome Atlas (TCGA) were investigated and visualised with OncoPrint and a clustered heatmap. RESULTS: On first-line anti-EGFR treatment, patients with middle/low rectal tumours had significantly lower progression-free survival, overall survival, and overall response rates (6.8 months, 27.8 months and 43%, respectively) than those with left-sided colon cancer (10.1 months, 38.3 months and 66%, respectively). Similar outcomes were also identified on non-first-line anti-EGFR treatment. In TCGA analysis, rectal tumours displayed genetic heterogeneity and shared features with both left- and right-sided colon cancer. CONCLUSIONS: Anti-EGFR treatment has lower efficacy in metastatic middle/low rectal cancer than in left-sided colon cancer.

Insulin-Like Growth Factor 2 mRNA-Binding Protein 1 (IGF2BP1) Is a Prognostic Biomarker and Associated with Chemotherapy Responsiveness in Colorectal Cancer.

Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) is an RNA-binding protein and serves as a post-transcriptional fine-tuner regulating the expression of mRNA targets. However, the clinicopathological roles of IGF2BP1 in colorectal cancer (CRC) remains limited. Thus, we aimed to elucidate the clinical significance and biomarker potentials of IGF2BP1 in CRC. A total of 266 specimens from two sets of CRC patients were collected. IGF2BP1 expression was studied by immunohistochemical (IHC) staining. The Kaplan-Meier survival plot and a log-rank test were used for survival analysis. The Cox proportional hazards model was applied to determine the survival impact of IGF2BP1. Public datasets sets from The Cancer Genome Atlas (TCGA) and Human Cancer Metastasis Database (HCMDB), receiver operating characteristic (ROC) plotter, and two CRC cell lines, HCT-116 and DLD-1, were used for validating our findings. We showed that IGF2BP1 was overexpressed in tumor specimens compared to 13 paired normal parts by examining the immunoreactivity of IGF2BP1 (p = 0.045). The increased expression of IGF2BP1 in primary tumor parts was observed regardless of metastatic status (p < 0.001) in HCMDB analysis. IGF2BP1 expression was significantly associated with young age (59.6% vs. 46.7%, p-value = 0.043) and advanced stage (61.3% vs. 40.0%, p-value = 0.001). After controlling for confounding factors, IGF2BP1 remained an independent prognostic factor (HR = 1.705, p-value = 0.005). TCGA datasets analysis indicated that high IGF2BP1 expression showed a lower 5-year survival rate (58% vs. 65%) in CRC patients. The increased expression of IGF2BP1 in chemotherapy non-responder rectal cancer patients was observed using a ROC plotter. Overexpression of IGF2BP1 promoted the colony-forming capacity and 5-fluorouracil and etoposide resistance in CRC cells. Here, IGF2BP1 was an independent poor prognostic marker in CRC patients and contributed to aggressive phenotypes in CRC cell lines.

SMAD3 Hypomethylation as a Biomarker for Early Prediction of Colorectal Cancer.

The incidence and mortality rates of colorectal cancer (CRC) have been high in recent years. Prevention and early detection are crucial for decreasing the death rate. Therefore, this study aims to characterize the alteration patterns of mothers against decapentaplegic homolog 3 (SMAD3) in patients with CRC and its applications in early detection by using a genome-wide methylation array to identify an aberrant hypomethylation site in the intron position of the SMAD3 gene. Quantitative methylation-specific polymerase chain reaction showed that hypomethylated SMAD3 occurred in 91.4% (501/548) of Taiwanese CRC tissues and 66.6% of benign tubular adenoma polyps. In addition, SMAD3 hypomethylation was observed in 94.7% of patients with CRC from The Cancer Genome Atlas dataset. A decrease in circulating cell-free methylation SMAD3 was detected in 70% of CRC patients but in only 20% of healthy individuals. SMAD3 mRNA expression was low in 42.9% of Taiwanese CRC tumor tissues but high in 29.4% of tumors compared with paired adjacent normal tissues. Hypomethylated SMAD3 was found in cancers of the digestive system, such as liver cancer, gastric cancer, and colorectal cancer, but not in breast cancer, endometrial cancer, and lung cancer. In conclusion, SMAD3 hypomethylation is a potential diagnostic marker for CRC in Western and Asian populations.

Comparison of the Clinicopathological Characteristics and Genetic Alterations Between Patients with Gastric Cancer with or Without Helicobacter pylori Infection.

BACKGROUND: Helicobacter pylori (HP) can induce epithelial cells and intestinal metaplasia with genetic damage that makes them highly susceptible to the development of gastric cancer (GC). MATERIALS AND METHODS: Between 2005 and 2010, 356 patients with gastric cancer who received curative surgery were enrolled. Analysis of HP, Epstein-Barr virus (EBV) infection, PIK3CA amplification, and mutation analysis of 68 mutations in eight genes using a mass spectrometric single-nucleotide polymorphism genotyping technology was conducted. The clinicopathological characteristics of patients with or without HP infection were compared. RESULTS: Among the 356 patients, 185 (52.0%) had HP infection. For intestinal-type GC, patients with HP infection were more likely to be younger and had fewer PI3K/AKT pathway genetic mutations than those without HP infection. For diffuse-type GC, patients with HP infection were characterized by less male predominance, less lymphoid stroma, fewer microsatellite instability-high tumors, and fewer PI3K/AKT pathway genetic mutations than those without HP infection. Patients with HP infection had less tumor recurrence and a better 5-year overall survival (87.7% vs. 73.9%, p = .012) and disease-free survival (64.1% vs. 51.3%, p = .013) than those without HP infection, especially for intestinal-type GC. For EBV-negative GC, patients with HP infection had fewer PI3K/AKT pathway mutations and a better 5-year overall survival and disease-free survival than those without HP infection. Multivariate analysis demonstrated that HP infection was an independent prognostic factor regarding overall survival and disease-free survival. CONCLUSION: Patients with GC with HP infection were associated with fewer PI3K/AKT pathway genetic mutations and better survival than those without HP infection, especially for EBV-negative and intestinal-type GC. IMPLICATIONS FOR PRACTICE: Patients with gastric cancer with Helicobacter pylori (HP) infection had fewer PI3K/AKT pathway genetic mutations, less tumor recurrence, and better survival than those without HP infection, especially for Epstein-Barr virus (EBV)-negative and intestinal-type gastric cancer. HP infection is an independent prognostic factor regarding overall survival and disease-free survival. Future in vivo and in vitro studies of the correlation among HP infection, PI3K/AKT pathway, and EBV infection in gastric cancer are required.

Combined Microsatellite Instability and Elevated Microsatellite Alterations at Selected Tetranucleotide Repeats (EMAST) Might Be a More Promising Immune Biomarker in Colorectal Cancer.

BACKGROUND: The form of microsatellite instability (MSI) affecting tetranucleotide repeats known as elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) has emerged as a new potential biomarker in multiple cancers. In colorectal cancer (CRC), the correlation between EMAST and MSI mutations remain inconclusive. MATERIALS AND METHODS: We evaluated 1,505 patients with CRC using five EMAST markers (D20S82, D20S85, D8S321, D9S242, and MYCL1) and the Bethesda panel of MSI markers. Most commonly, mutations involved in CRCs were identified by MassArray Assay, and DNA repair genes were analyzed by next-generation sequencing. Clinical characteristics and prognostic relevance were correlated with EMAST and MSI. RESULTS: Tumors that were EMAST positive and MSI high (MSI-H) were detected in 159 (10.6%) and 154 (10.2%) of 1,505 patients with CRC. Patients were divided into four groups according to EMAST and MSI status (EMAST-positive and MSI-H, EMAST-positive and microsatellite-stable [MSS], EMAST-negative and MSI-H, and EMAST-negative and MSS). The EMAST-positive and MSI-H group was associated with female predominance, higher prevalence of proximal colon tumors, early stage tumors, poorly differentiated tumors, mucinous histology, and higher incidence of mutations in PI3KCA, BRAF, TGFBR, PTEN, and AKT1 compared with other groups. Furthermore, compared with only EMAST-positive tumors or only MSI-H tumors, tumors that were both EMAST-positive and MSI-H had a higher frequency of MLH1, MSH3, MSH6, PMS2, and EXO1 gene mutations. Finally, the presence of EMAST-positive and MSI-H tumors was a good prognostic indicator in CRC. CONCLUSION: High mutations in several DNA repair genes in EMAST-positive and MSI-H tumors suggest that this subtype of CRC might be more suitable for treatment with immune therapy. IMPLICATIONS FOR PRACTICE: Elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) is a unique molecular subtype of colorectal cancer (CRC). The current study demonstrated that the EMAST-positive and MSI-high (MSI-H) group was associated with female predominance, higher prevalence of proximal colon tumors, early stage tumors, poorly differentiated tumors, mucinous histology, and higher incidence of mutations in PI3KCA, BRAF, TGFBR, PTEN, and AKT1 compared with other groups. Most importantly, high mutations in DNA repair genes and MSI-related genes in EMAST-positive and MSI-H tumors suggest that this subtype of CRC might be more suitable for treatment with immune therapy compared with MSI-H tumors alone.

Prognosticators of Long-Term Outcomes of TNM Stage II Colorectal Cancer: Molecular Patterns or Clinicopathological Features.

BACKGROUND: Patients with stage II colorectal cancer (CRC) have a higher risk of recurrence when they have certain risk factors, including clinical and pathological patterns. However, as the prognostic role of molecular patterns for stage II disease is still unclear, this study aimed to investigate it. METHODS: A total of 509 patients with stage II CRC were enrolled, and all clinical, pathological, and molecular data were collected. Molecular patterns included microsatellite instability (MSI); elevated microsatellite alterations at selected tetranucleotides (EMAST) status; and expression of RAS/RAF genes, genes of the APC pathway, and other gene mutations. The endpoints were oncological outcomes, including overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), local recurrence (LR), and distant recurrence (DR). Cox regression analysis was used. RESULTS: Numerous molecular patterns influenced the oncological outcomes on univariate analysis, but no variable reached significance in LR. On multivariate analysis, a mucinous component (MC) > 50% (P < 0.01) was significant for OS and CSS. Lymphovascular invasion (LVI; P< 0.01), MC > 50% (P < 0.01), and EMAST-H (P = 0.02) significantly influenced DFS, whereas LVI (P < 0.01), MC > 50% (P < 0.01), and TP53 mutation (P = 0.02) were significant for DR. CONCLUSIONS: In this study, MSI, EMAST, and RAS/RAF alterations did not influence the oncological outcomes. Overall, LVI and MC were two significant prognostic factors for DFS and DR. Thus, the histopathology, rather than the genes, plays a major role in the prognosis of patients with stage II CRC.

Risk factors for delayed perineal wound healing and its impact on prolonged hospital stay after abdominoperineal resection.

BACKGROUND: Perineal wound complications are a long-lasting issue for abdominoperineal resection (APR) patients. Complication rates as high as 60% have been reported, with the most common complication being delayed perineal wound healing. The aim of this study was to identify risk factors for delayed perineal wound healing and its impact on prolonged hospital stay. METHODS: We included low rectal tumor patients who underwent APR at a referral medical center from April 2002 to December 2017; a total of 229 patients were included. The basic characteristics and surgical outcomes of the patients were analyzed to identify risk factors for delayed perineal wound healing (> 30 days after APR) and prolonged hospital stay (post-APR hospital stay > 14 days). RESULTS: All patients received primary closure for their perineal wound. The majority of patients were diagnosed with adenocarcinoma (N = 213, 93.1%). In the univariate analysis, patients with hypoalbuminemia (albumin < 3.5 g/dL) had an increased risk of delayed wound healing (39.5% vs. 60.5%, P = 0.001), which was an independent risk factor in the multivariable analysis (OR 2.962, 95% CI 1.437-6.102, P = 0.003). Patients with delayed wound healing also had a significantly increased risk of prolonged hospital stay (OR 6.404, 95% CI 3.508-11.694, P < 0.001). CONCLUSIONS: Hypoalbuminemia was an independent risk factor for delayed wound healing, which consequently led to a prolonged hospital stay. Further clinical trials are needed to reduce the incidence of delayed perineal wound healing by correcting albumin levels or nutritional status before APR.

Clinical significance of the BRAFV600E mutation in Asian patients with colorectal cancer.

BACKGROUND: To investigate the clinicopathological features and prognostic significance of the BRAFV600E mutation in Asian patients with colorectal cancer. METHODS: We retrospectively reviewed the medical records of 1969 patients with colorectal cancer admitted to Taipei Veterans General Hospital for surgical treatment between 2000 and 2013. The measured endpoint was overall survival after surgery. The prognostic value of the BRAFV600E mutation was analyzed using the log-rank test and Cox regression analysis. RESULTS: The BRAFV600E mutation was detected in 106 (5.4%) patients and associated with female gender, abnormal cancer antigen (CA)19-9 at diagnosis, microsatellite status, right-sided primary tumors, mucinous histology, poor differentiation, and lymphovascular invasion. Metastatic patterns were more common in non-regional lymph node metastasis (20.8 vs. 7.4%, p = 0.06) and peritoneal seeding (41. vs. 21.2%, p = 0.04). Mutations were not prognostic in the overall survival of the entire study group but only in specific patients: age < 65, normal carcinoembryonic antigen at diagnosis, and stage IV disease. CONCLUSION: The BRAFV600E mutation was associated with distinct clinicopathological features and metastatic patterns. The overall survival rate was lower in selected colorectal patients with the BRAFV600E mutation.

Differences in gene mutations according to gender among patients with colorectal cancer.

BACKGROUND: The incidence, site distribution, and mortality rates of patients with colorectal cancer differ according to gender. We investigated gene mutations in colorectal patients and wanted to examine gender-specific differences. METHODS: A total of 1505 patients who underwent surgical intervention for colorectal cancer were recruited from March 2000 to January 2010 at Taipei Veterans' General Hospital and investigated for gene mutations in K-ras, N-ras, H-ras, BRAF, loss of 18q, APC, p53, SMAD4, TGF-ß, PIK3CA, PTEN, FBXW7, AKT1, and MSI. RESULTS: There were significant differences between male and female patients in terms of tumor location (p < 0.0001) and pathological stage (p = 0.011). The female patients had significantly more gene mutations in BRAF (6.4 vs. 3.3%, OR 1.985, p = 0.006), TGF-ß (4.7 vs. 2.5%, OR 1.887, p = 0.027), and revealed a MSI-high status (14.0 vs. 8.3%, OR 1.800, p = 0.001) than male patients. Male patients had significantly more gene mutations in N-ras (5.1 vs. 2.3%, OR 2.227, p = 0.012); however, the significance was maintained only for mutations in BRAF (OR 2.104, p = 0.038), MSI-high status (OR 2.003 p = 0.001), and N-ras (OR 3.000, p = 0.010) after the groups were divided by tumor site. CONCLUSION: Gene mutations in BRAF, MSI-high status, and N-ras differ according to gender among patients with colorectal cancer.

Molecular and Clinicopathological Differences by Age at the Diagnosis of Colorectal Cancer.

We compared the clinicopathological and molecular profiles between different age groups of sporadic colorectal cancer (CRC) patients (age <50, 56-60, 60-70, 70-80, and >80); 1475 CRC patients were enrolled after excluding 30 individuals with Lynch syndrome. The mutation spectra for APC, TP53, KRAS, PIK3CA, FBXW7, BRAF, NRAS, HRAS, TGFbR, Akt1, and PTEN were analyzed using polymerase chain reaction (PCR), followed by MassArray and microsatellite (MSI-high) analysis by performing genotyping. Male patients (74.1%) were significantly predominant to females (25.9%) in the older age group (70-80, >80). There was an insignificantly linear trend between TNM staging and age-onset of CRC diagnosis. Patients aged < 50 had 58.7% diseases in the advanced stages (Stage III: 36.5% and IV: 22.2% respectively), while this decreased to 40.2% (Stage III: 26.2% and IV; 14.0% respectively) in patients >80. The distributions of mutation frequency were similar in majority of the genes studied among different age groups. Additionally, patients aged <50 had significantly higher frequency of MSI-high, PTEN, and HRAS mutations than those of other groups. Age-onset at diagnosis significantly affected overall survival (HR = 1.46; 95% CI: 1.35-1.58), but not cancer-specific survival (HR = 1.08; 95% CI: 0.99-1.18) in multivariate analysis. In conclusion, molecular and clinicopathological differences were not as significant among different age groups of CRC patients as previously suspected.

Clinical significance of circulating plasma DNA in gastric cancer.

With the progression of molecular techniques, the detection of circulating plasma DNA (cpDNA) is clinically feasible. However, the role of the cpDNA levels in gastric cancer is not well understood. This study assessed the mutational profile in primary tumors and clarified the clinical utility of quantitative and qualitative cpDNA alterations in 277 patients with advanced gastric cancer. The concentrations of cpDNA were measured by TaqMan qPCR, and 68 mutations in 8 genes were studied for cpDNA mutations. The median cpDNA concentrations in patients with stages I, II, and III gastric cancer were 3979, 3390 and 4278 copies/mL, respectively, and increased to 11,380 copies/mL in patients with Stage IV gastric cancer (p < 0.001). Among the 35 patients harboring cpDNA mutations, Stage IV patients (100%) were more likely to display high cpDNA levels than were Stage I (33.3%), II (75%) and III patients (66.7%) (p = 0.037). Patients displaying high cpDNA levels were more likely to experience peritoneal recurrence and exhibited significantly lower 5-year overall survival rates (39.2% vs. 45.8%, p = 0.039) than did patients displaying low cpDNA levels. Only for late stage (Stages III or IV) gastric cancer, patients harboring cpDNA mutations were more likely to experience vascular invasion (20% vs. 2.4%, p = 0.036) and exhibited a lower 5-year overall survival rate than did those lacking cpDNA mutations (5.6% vs. 31.5%, p = 0.028). High cpDNA levels are associated with peritoneal recurrence and poor prognosis in patients with advanced gastric cancer; harboring cpDNA mutations is associated with poor prognosis among patients with late stage gastric cancer.

Mutation Spectra of Common Cancer-Associated Genes in Different Phenotypes of Colorectal Carcinoma Without Distant Metastasis.

BACKGROUND: Colorectal cancer (CRC) is a heterogeneous disease caused by genetic and epigenetic alterations. This study aimed to describe the mutation frequency of 12 genes in different CRC phenotypes. METHODS: Patients who underwent surgery at the Taipei Veterans General Hospital during 2000-2010 for CRC (n = 1249) were enrolled. The endpoint was overall survival. The prognostic value was determined with the log-rank test and Cox regression analysis. RESULTS: We found 1836 mutations of 12 genes in 997 (79.8%) tumors. Mutations were most frequently in KRAS (485, 38.8%), TP53 (373, 29.9%), APC (363, 29.0%), and PIK3CA (179, 14.3%); 137 (11.0%) cancers had high microsatellite instability (MSI). Women had significantly higher high MSI (14.3%) and BRAF mutation (6.3%) frequencies. The abnormal MSI (21.7%) and KRAS (44.6%), BRAF (8.6%), PIK3CA (19.4%), AKT1 (2.2%), and TGF - ßR (9.6%) mutation frequencies were significantly higher in proximal colon cancer. The high MSI (35.6%) and BRAF (20.3%), TGF - ßR (18.6%), PTEN (5.1%), and AKT1 (3.4%) mutation frequencies were significantly higher in 59 (4.7%) poorly differentiated tumors. The high MSI (21.3%) and KRAS (51.9%), BRAF (8.3%), PIK3CA (25.0%), AKT1 (4.6%), and SMAD4 (8.3%) mutation frequencies were significantly higher in 108 mucinous tumors. TNM stage, lymphovascular invasion, and mucinous histology were significantly associated with patient outcomes in univariate and multivariate analyses. Only NRAS mutation (hazard ratio 1.59, 95% confidence interval 1.06-2.38) affected patient survival. CONCLUSIONS: Mutational spectra differ significantly between CRC subtypes, implying diverse carcinogenetic pathways. The NRAS mutation is important, despite its low frequency.

Immunohistochemical detection of the BRAF V600E mutant protein in colorectal cancers in Taiwan is highly concordant with the molecular test.

AIMS: The aims of this study were to investigate the incidence of BRAF mutations in colorectal cancers (CRCs) in Taiwan and the sensitivity and specificity of VE1 immunohistochemistry in detecting the BRAF(V) (600E) mutation. METHODS AND RESULTS: A total of 425 resected colorectal adenocarcinoma specimens were recruited into this study. Direct Sanger sequencing of exon 15 of the BRAF gene was performed for all cases. The incidence of BRAF mutation was 5.4% (23 of 425). Tissue microarrays were constructed for VE1 immunohistochemistry, and the staining intensity was scored as negative (0), weak (1+), moderate (2+) and strong (3+). In BRAF-mutated cases, two (8.7%) scored as 0, three (13.0%) as 1+, 13 (56.5%) as 2+ and five (21.7%) as 3+. Among 402 BRAF wild-type cases, five (1.2%) were scored as 1+, while the others were negative. The sensitivity and specificity of VE1 expression in detecting the BRAF mutation was 91.3% and 98.8%, respectively. CONCLUSIONS: Immunohistochemistry for VE1 antibody is a sensitive and specific marker for detection of BRAF mutations in CRCs. Incorporation of VE1 immunohistochemistry into Lynch syndrome screening protocol may be a reliable and cost-effective method.

Improved outcomes of colorectal cancer patients with liver metastases in the era of the multidisciplinary teams.

PURPOSE: The use of multidisciplinary teams (MDTs), which address colorectal cancer treatment planning through weekly regular group meetings, was begun in October 2007. We analyzed and compared the outcomes of colorectal cancer patients with metastatic disease before and after the era of MDTs. METHODS: From 2001 to 2010, 1075 patients who presented with stage IV disease and were treated in Taipei Veterans General Hospital were enrolled in the study. Among these patients, 439 (40.8%) were diagnosed after MDTs had been established. The percentage of patients receiving surgical treatment for metastatic disease was calculated and compared before and after MDTs were established, and the survival rate was compared using a log-rank test, with a significance of P < 0.05. RESULTS: A significantly improved survival rate in patients with stage IV disease was observed after establishment of MDTs, with the 3-year survival rate increasing from 25.6 to 38.2% (P < 0.001). Based on multivariate analysis, establishment of a MDT was an independent prognostic factor in patients with stage IV disease (hazard ratio = 0.74, 95% confidence interval = 0.624∼0.866, P < 0.001). The percentage of liver resection in patients with liver metastasis increased from 19.6 to 35.2% after the establishment of MDTs, whereas the percentage of lung resection in patients with lung metastasis remained stationary from 12.4 to 14.3%. CONCLUSIONS: In the era of MDTs, intensive cooperation between different specialists has increased the referral rate for metastasectomy, resulting in significantly improved outcomes of colorectal patients in initial stage IV disease.

Elevated serum alpha-fetoprotein in poorly differentiated adenocarcinoma with neuroendocrine differentiation of the ascending colon: a case report.

BACKGROUND: Colorectal cancer (CRC) is the most common form of cancer and the third leading cause of death in Taiwan. Serum alpha-fetoprotein (AFP) has been extensively used as a biomarker for hepatocellular carcinoma (HCC) and yolk sac tumors. CASE PRESENTATION: This case report presents a 90-year-old woman with right abdominal pain and poor appetite for 1 week. The computed tomography (CT) showed wall thickening in the proximal ascending colon with ruptured appendicitis. Preoperative serum AFP was high. There was no definite liver metastasis or other abnormal findings in the hepatobiliary systems. After initial empirical antibiotic treatment, we performed laparoscopic right hemicolectomy. The pathological assessment was poorly differentiated adenocarcinoma with neuroendocrine differentiation in the ascending colon. The tumor cells did not produce AFP. Amazingly, the follow-up serum AFP level 1 month after the surgery declined to normal range. The patient had an uneventful course after the surgery and was free of recurrence or metastasis within 5 months of follow-up. CONCLUSIONS: AFP may be a useful tumor marker in poorly differentiated colorectal cancer with neuroendocrine component patients and a prediction of early treatment response.

Circulating Cell-Free DNA Levels Could Predict Oncological Outcomes of Patients Undergoing Esophagectomy for Esophageal Squamous Cell Carcinoma.

Circulating cell-free DNA (cfDNA) is a potential biomarker for cancer progression but its role is unclear in patients with esophageal squamous cell carcinoma (ESCC) after esophagectomy. We investigated relationships between plasma cfDNA levels and clinicopathological parameters in ESCC patients. Eighty-one ESCC patients who received esophagectomy were enrolled. Plasma samples from these patients and 95 normal controls were collected. DNA copy numbers were measured by real-time quantitative PCR. Subjects were divided into two groups by cfDNA level. Clinicopathological data were collected retrospectively and relationships between cfDNA levels and clinical parameters were evaluated. The cfDNA level in normal controls ranged from 0-4157 copies/mL. The cfDNA level of 96.3% ESCC patients was higher than the cutoff value (2447.26 copies/mL) with a specificity of 94.1%. The mean cfDNA concentration was 5918 copies/mL in lower and 53,311 copies/mL in higher cfDNA groups. No correlations were found between clinicopathological factors and cfDNA levels except for lymphovascular invasion. Higher cfDNA levels were associated with tumor relapse (p = 0.018). Five-year disease-free survival (DFS) and overall survival (OS) rates were 34.7% and 33.8%, respectively. Patients with higher cfDNA levels had poorer DFS (p = 0.013). Patients with higher cfDNA levels had poorer OS, but not significantly (p = 0.164). Circulating cfDNA could be a biomarker for tumor relapse of ESCC with high sensitivity and specificity. Higher cfDNA levels were associated with tumor relapse and shorter DFS after esophagectomy in ESCC patients.