Prevalence of sleep disturbances and their effects on quality of life in adults with untreated pituitary tumor and meningioma.

PURPOSE: To explore the prevalence of sleep disturbances and their effects on quality of life in adults with pituitary tumor or meningioma. METHODS: This prospective study included 33 and 44 patients with pituitary tumor and meningioma, respectively. All participants completed a series of valid questionnaires for assessing sleep and quality of life; all participants wore 3-day actigraph prior to related treatment. The actigraph-derived sleep parameters included total sleep time, sleep onset latency, wake after sleep onset, sleep efficiency, and dichotomy index (I < O) value. RESULTS: The prevalence of insomnia, excessive daytime sleepiness, and poor sleep quality was 46.8%, 6.5%, and 81.8%, respectively. The differences in these sleep parameters between patients with pituitary tumor and those with meningioma were nonsignificant. Only 27 participants completed the actigraphic assessments. The mean I < O value was 95.99%, and nearly 60% participants exhibited circadian rhythm disruption. Sleep quality was the only sleep variable independently correlated with preoperative quality of life, even after adjustments for confounders (B = 0.80, p = 0.02). CONCLUSIONS: Insomnia, poor sleep quality, and disrupted circadian rhythm are highly prevalent in adults with untreated pituitary tumor or meningioma. Sleep quality independently correlated with quality of life. We indirectly confirmed that tumor location may not be a possible cause of sleep changes.

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.

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.

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.

Clinical Relevance of Plasma DNA Methylation in Colorectal Cancer Patients Identified by Using a Genome-Wide High-Resolution Array.

BACKGROUND: DNA methylation is a potential tumor marker for several cancers, including colorectal cancer (CRC), because of its heritable and stable characteristics. METHODS: Using a high-resolution, genome-wide approach, we epigenotyped >450,000 CpG sites in tumor and adjacent non-tumor tissues from 23 microsatellite instability (MSI)/microsatellite stability (MSS) CRC cases. Using matrix-assisted laser desorption ionization-time of flight mass spectrometry, the methylation status of five frequently hypermethylated genes were confirmed in 75 independent CRC series and 353 CRC patients with available plasma. RESULTS: Compared with non-tumor tissues, 13 MSI tumors had 34,836 (7 %) aberrant methylation sites, 87 % of which were hypermethylated. In contrast, only 9,806 (2 %) differentially methylated sites were identified in ten MSS cases (62 % hypermethylated). In both MSI and MSS, 228 promoter-associated CpG islands were hypermethylated, with AGBL4, ZNF625, MDFI, TWIST1, and FLI1 being most frequently hypermethylated. In an independent set of 35 MSI and 40 MSS cases, the methylation status of these five genes significantly differed between tumor and adjacent non-tumor tissues. Of 353 CRC patients, 230 (65.2 %), 232 (65.7 %), and 247 (70.0 %) had AGBL4, FLI1, and TWIST1 promoter hypermethylation in circulating cell-free DNA, respectively. In patients without metastasis, the sensitivity of any two or three hypermethylation markers was 52.8-57.8 and 27.9-38.9 %, respectively. The sensitivity of any two or three markers was significantly high in patients with stage IV disease (73.0 and 55.6 %, respectively). The prognostic value of these epimarkers was inconclusive. CONCLUSION: DNA methylation patterns differed in CRC subtypes. The identified hypermethylation markers in CRC patients may have good sensitivity in different CRC stages.

A comprehensive analysis of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) loss in colorectal cancer.

BACKGROUND: Alterations of PTEN, regulator of the PTEN/PI3K-AKT pathway, are common in several types of cancer. This study aimed to do comprehensive analysis of PTEN in colorectal cancer patients. METHODS: Totally, 198 colorectal cancer patients who received surgery at Taipei Veterans General Hospital from 2006 to 2008 were enrolled. Mutations, loss of protein expression, promoter hypermethylation, and DNA copy number of PTEN were analyzed by sequencing, immunohistochemistry, methylation-specific polymerase chain reaction PCR, and quantitative (QPCR), respectively, and correlated with clinicopathological features and patients' outcome. RESULTS: Genomic mutations, loss of protein expression, promoter hypermethylation, and decreased DNA copy number of PTEN were found in 4 (2.02 %), 68 (34.3 %), 54 (27.3 %), and 36 (18.2 %) tumors, respectively. Of these 68 tumors with loss expression of PTEN, 34 (50 %) tumors had promoter methylation and 18 (26.5 %) had decreased DNA copy number. All four tumors with PTEN mutations demonstrated loss of PTEN expression. In the stage I disease, frequency of loss of PTEN expression was 20 % and significantly increased to 56.9 % in stage IV disease. Either loss expression of PTEN, PTEN hypermethylation or decreased PTEN copy number was not associated with colorectal cancer (CRC) patients' outcome. CONCLUSIONS: PTEN alterations were found in up to one-third of colorectal cancers but did not impact CRC patients' prognosis.

Clinical relevance of alterations in quantity and quality of plasma DNA in colorectal cancer patients: based on the mutation spectra detected in primary tumors.

BACKGROUND: While circulating plasma DNA (cpDNA) likely originates in tumors, its utility is limited without knowledge of tumor mutations. This study assessed mutational spectra in primary tumors and clarified the utility of quantitative and qualitative cpDNA alterations in colorectal cancer (CRC) patients. MATERIALS AND METHODS: Between 2005 and 2006, 191 surgical colorectal cancer patients at Taipei Veterans General Hospital were enrolled in a study of mutational spectra of 155 mutations in 74 genes. Concentrations of cpDNA in 133 patients were measured by Taqman qPCR. The measured endpoint was overall survival (OS) after surgery. The prognostic value was determined using the log-rank test and Cox regression analysis. RESULTS: Of 191 tumors, 208 mutations in 17 genes were found in 137 tumors (71.7 %). Mutation frequencies were 38.7 % in KRAS, followed by APC (23.0 %), TP53 (19.9 %), PIK3CA (7.3 %), and BRAF (4.2 %). The median cpDNA in stage I, II, and III patients was 4,300, 4,800, and 5,600 copies/mL, respectively, increasing to 13,000 copies/mL in stage IV disease (p = .003). From 90 primary tumors with mutations, the sensitivity of cpDNA mutations were 24.0, 45.0, and 27.3 % in the stage I, II, and III disease, respectively, increasing to 87.5 % in stage IV. The 5-year OS of CRC patients with low cpDNA was significantly better than that of patients with high cpDNA (p = .001). Stepwise elimination showed cpDNA to be a strong prognostic factor for OS. CONCLUSIONS: Plasma DNA alteration is a useful tool for clinical surveillance of colorectal cancer patients and might be an independent prognosticator.

The impact of the lymph node ratio is greater than traditional lymph node status in stage III colorectal cancer patients.

BACKGROUND: The prognostic value of nodal status in colorectal cancer (CRC) patients may be influenced by the total number of lymph nodes (LNs) harvested. This study evaluates the impact of LN ratio (LNR) on CRC patients' outcome. METHODS: A total of 612 stage III CRC patients who underwent curative-intent surgery between 2004 and 2008 were enrolled. The measured end point was postoperative disease-free survival (DFS) and overall survival (OS). RESULTS: The metastatic LN numbers were significantly higher in patients with more than 12 LN harvested (4.6 ± 5.81 vs. 2.7 ± 1.97, P < 0.001). The mean LNR was 22.9 ± 20 % (range = 2-100 %, median = 16.7 %). As the cutoff value of LNR was set above 17 %, the impact of the LNR on 5-year DFS became statistically significant. In univariate analysis, the 5-year DFS and OS for patients with high-LNR tumors was 54.4 and 57.3 %, respectively, significantly lower than those for patients with low-LNR tumors (72.8 and 76.4 %; P < 0.001). In multivariate analysis, the independent factors affecting the 5-year DFS and OS were tumor depth, carcinoembryonic antigen level, and LNR. CONCLUSION: The LNR, set at the median value or 17 %, could be an independent prognostic factor for stage III CRC patients.

Hypothermia is an independent risk factor for prolonged ICU stay in coronary artery bypass surgery: an observational study.

Maintenance of normothermia is a critical perioperative issue. The warming process after hypothermia tends to increase oxygen demand, which may lead to myocardial ischemia. This study explored whether hypothermia was an independent risk factor for increased morbidity and mortality in patients receiving CABG. We conducted a retrospective observational study of CABG surgeries performed from January 2018 to June 2019. The outcomes of interest were mortality, surgical site infection rate, ventilator dependent time, intensive care unit (ICU) stay, and hospitalization duration. Data from 206 patients were analysed. Hypothermic patients were taller (p = 0.012), had lower left ventricular ejection fraction (p = 0.016), and had off-pump CABG more frequently (p = 0.04). Our analysis noted no incidence of mortality within 30 days. Hypothermia was not associated with higher surgical site infection rate or longer intubation time. After adjusting for sex, age, cardiopulmonary bypass duration, left ventricular ejection fraction, and EuroSCORE II, higher EuroSCORE II (p < 0.001; odds ratio 1.2) and hypothermia upon ICU admission (p = 0.04; odds ratio 3.8) were independent risk factors for prolonged ICU stay. In addition to EuroSCORE II, hypothermia upon ICU admission was an independent risk factor for prolonged ICU stay in patients receiving elective CABG.

Sleep disturbance in adults with untreated primary brain tumors: prevalence and impact on quality of life.

Purpose: To investigate the frequency of sleep disturbance and its effects on quality of life in adults with untreated primary brain tumors. Methods: This cross-sectional study recruited 68 and 35 patients with newly diagnosed benign and malignant brain tumors, respectively. All participants completed the Chinese versions of the Athens Insomnia Scale, Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Hospital Anxiety and Depression Scale, Brief Fatigue Inventory, and EORTC-QLQ-BN20 for quality-of-life assessment. An actigraph was used to measure sleep parameters [e.g., dichotomy index (I < O)], for at least 3 consecutive days in untreated status. Results: The majority of the patients with benign and malignant tumors had meningioma (57.4%) and glioblastoma (40%), respectively. The prevalence of insomnia, poor sleep quality, and excessive daytime sleepiness was 59.2%, 77.7%, and 4.9%, respectively. The prevalence rates of sleep disturbances were not affected by tumor locations (suprasellar vs. non-suprasellar tumors) and tumor types (benign vs. malignant tumors). Only 36 participants completed actigraphy assessments (I < O = 95.4) due to having a tight schedule, actigraph malfunction, or not having the habit of wearing a wristwatch; 61% of them experienced circadian rhythm disruption (I < O ≤ 97.5). Insomnia was the only sleep parameter that significantly affected quality of life after controlling for potential confounders (B = 0.54, p = 0.03, adjusted R2 = 0.60). Conclusion: More than 60% of the patients with primary malignant and benign brain tumors experienced insomnia, poor sleep quality, and circadian rhythm disruption. Insomnia was independently correlated with quality of life in untreated status. Health-care providers can apply these findings to design effective interventions targeting sleep disturbance to improve quality of life in this population. Supplementary Information: The online version contains supplementary material available at 10.1007/s41105-022-00436-y.

Carbohydrate antigen 19-9 is a valuable prognostic factor in colorectal cancer patients with normal levels of carcinoembryonic antigen and may help predict lung metastasis.

PURPOSE: We retrospectively analyzed preoperative levels of carbohydrate antigen (CA) 19-9 in colorectal cancer (CRC) patients to determine the prognostic value of CA19-9 in CRC patients with normal carcinoembryonic antigen (CEA) levels. METHODS: A total of 639 patients who underwent curative surgery at Taipei Veterans General Hospital between 2002 and 2006 were enrolled. We excluded 254 patients (39.7 %) with high preoperative CEA levels and analyzed 385 patients with normal CEA levels. The measured endpoint was the postoperative disease-free survival (DFS). The prognostic value of CA19-9 was determined using log-rank test and Cox regression analysis. RESULTS: High CA19-9 levels were significantly associated with advanced disease and were detected in 5.8 % of patients with stage I disease, 11.7 % of those with stage II disease, and 22.5 % of those with stage III disease (P < 0.001). The 5-year DFS in patients with normal CA19-9 levels was 82.0 %, which was significantly higher than that in patients with high CA19-9 levels (68 %; P < 0.001). In a multivariate analysis, the most important independent factor affecting the 5-year DFS was tumor-node-metastasis stage (95 % CI, 1.26-2.36; HR = 1.72). After stratification by other factors, high CA19-9 level remained an independent prognostic factor for patients with normal CEA levels. Patients with high CA19-9 levels also showed a higher incidence of lung metastasis (23.1 %) than those with normal CA19-9 levels (7.2 %). CONCLUSIONS: CA19-9 may be a prognostic factor for CRC patients with normal CEA levels. An aggressive follow-up protocol for lung metastasis should be used for these patients.

High concordance of mutation patterns in 10 common mutated genes between tumor tissue and cell-free DNA in metastatic colorectal cancer.

The concordance of mutation patterns between cell-free DNA (cfDNA) and tumor DNA varies in colorectal cancers (CRCs). Next-generation sequencing (NGS) by targeted sequencing can detect novel genes. We aimed to use NGS to test the concordance between cfDNA and tumor DNA in metastatic CRCs. A total of 95 paired tumor and peripheral blood samples from metastatic CRC patients were included. The tumor DNA and cfDNA were analyzed with a 10-gene NGS panel (Illumina HiSeq2500 system). The median number of mutations in tumor samples was 3 (range 0-7). The most commonly mutated gene was TP53 (63.2%), followed by APC (49.5%), KRAS (35.8%) and FAT4 (15.8%). The concordance of mutation patterns in these 10 genes was as high as 91% between cfDNA and tumor samples in these metastatic CRC patients. A sensitivity of 88.2% and specificity of 100% was found when using KRAS mutation status of cfDNA to predict KRAS mutation in tumor tissue. For tumor DNA with TP53, KRAS, or APC mutations, right-sided CRCs were more likely to develop peritoneal metastases, while for tumor DNA with TP53 mutations, left-sided tumors were more likely to have lung metastases. For cfDNA with TP53 or KRAS mutations, right-sided CRCs were more likely to have peritoneal metastases. Due to the high concordance of mutation patterns between cfDNA and tumor samples, monitoring the mutation pattern of cfDNA may be applicable in the treatment of metastatic CRC.

Clinicopathological and Molecular Features of Patients with Early and Late Recurrence after Curative Surgery for Colorectal Cancer.

BACKGROUND: Few reports have investigated genetic alterations between patients with early and late recurrence following curative surgery for colorectal cancer (CRC). METHODS: A total of 1227 stage I-III CRC patients who underwent curative resection were included retrospectively. Among them, 236 patients had tumor recurrence: 139 had early (<2 years after surgery) and 97 had late (≥2 years after surgery) recurrence. Clinicopathological features and genetic alterations were compared between the two groups. RESULTS: Compared to those with late recurrence, patients with early recurrence were more likely to have advanced pathological node (N) categories; tumor, node, metastasis (TNM) stages; adjuvant chemotherapy treatment; liver metastases; APC mutations; and worse five-year overall survival rates. Patients with right-sided colon cancer were more likely to develop early recurrence than were those with left-sided colon cancer or rectal cancer. Regarding rectal cancer, patients with early recurrence were more likely to be at advanced pathological N categories and TNM stages than those with late recurrence. Multivariate analysis revealed old age, early recurrence, multiple-site recurrence, and BRAF and NRAS mutations to be independent prognostic factors. CONCLUSION: CRC patients with early recurrence have a worse OS rate and more APC mutations than those with late recurrence.

Clinicopathological and molecular features between synchronous and metachronous metastases in colorectal cancer.

The molecular difference between synchronous and metachronous metastases in colorectal cancer (CRC) remains unclear. Between 2000 and 2010, a total of 492 CRC patients were enrolled, including 280 with synchronous metastasis and 212 with metachronous metastasis. Clinicopathological and molecular features were compared between the two groups. Patients with synchronous metastasis were more likely to have right-sided CRC, poorly differentiated tumors, lymphovascular invasion, advanced pathological tumor (T) and node (N) categories, and liver metastases than those with metachronous metastasis. For right-sided CRC, patients with synchronous metastasis had more lymphovascular invasion and liver metastases than those with metachronous metastasis. For left-sided CRC, patients with synchronous metastasis were more likely to have poorly differentiated tumors, lymphovascular invasion, advanced pathological T and N categories, and liver metastases than those with metachronous metastasis. Regarding the genetic mutations, patients with metachronous metastasis had more mutations in TP53, NRAS, and HRAS and fewer mutations in APC than those with synchronous metastasis; for right-sided CRC, synchronous metastasis was associated with more APC mutations than metachronous metastasis, while for left-sided CRC, metachronous metastasis was associated with more TP53 and NRAS mutations than synchronous metastasis. The 5-year overall survival (OS) rates were significantly higher in metachronous metastasis patients than in synchronous metastasis patients, especially those with left-sided CRC. Multivariate analysis showed that age, sex, lymphovascular invasion, pathological N category, metachronous metastasis, and BRAF and NRAS mutations were independent prognostic factors affecting OS. CRC patients with synchronous metastasis had a worse OS than those with metachronous metastasis and exhibited distinct genetic mutations.

Clinicopathological and Molecular Features of Colorectal Cancer Patients With Mucinous and Non-Mucinous Adenocarcinoma.

BACKGROUND: The prognosis of mucinous adenocarcinoma (MAC) and non-mucinous adenocarcinoma (NMAC) in colorectal cancer (CRC) is controversial, and the molecular differences between them are unclear. METHODS: Between 2000 and 2010, a total of 1,483 CRC patients were included. Among them, 73 patients (4.9%) were diagnosed with MAC. The clinicopathological features and genetic alterations were compared between MAC and NMAC. RESULTS: After propensity score matching to balance age and sex between MAC and NMAC patients, 292 CRC patients (73 MAC and 219 NMAC) were enrolled in the analysis at a 1:3 ratio. In right-sided colon cancer, patients with MAC were more likely to have Borrmann types 3 and 4 tumors, poor differentiation, and advanced T category and tumor, node, metastasis (TNM) stage, chemotherapy, and a similar 5-year overall survival (OS) rate compared with patients with NMAC. In left-sided colon cancer and rectal cancer, patients with MAC were more likely to have Borrmann types 3 and 4 tumors, poor differentiation, lymphovascular invasion, advanced T and N categories and TNM stages, chemotherapy, and a worse 5-year OS rate than patients with NMAC. Regarding genetic alterations, for NMAC, right-sided colon cancer had more BRAF mutations than left-sided colon cancer and rectal cancer. For MAC, right-sided colon cancer was associated with more microsatellite instability-high tumors and more AKT1 mutations than left-sided colon cancer and rectal cancer. CONCLUSION: The genetic alterations are distinct between MAC and NMAC in CRC. Tumor location may have an impact on genetic alterations and patient prognosis in MAC and NMAC.

Patterns of germline and somatic mutations in 16 genes associated with mismatch repair function or containing tandem repeat sequences.

BACKGROUND: We assumed that targeted next-generation sequencing (NGS) of mismatch repair-associated genes could improve the detection of driving mutations in colorectal cancers (CRC) with microsatellite instability (MSI) and microsatellite alterations at selected tetranucleotide repeats (EMAST) and clarify the somatic mutation patterns of CRC subtypes. MATERIAL AND METHODS: DNAs from tumors and white blood cells were obtained from 81 patients with EMAST(+)/MSI-high (MSI-H), 78 patients with EMAST(+)/microsatellite stable (MSS), and 72 patients with EMAST(-)/MSI-H. The germline and somatic mutations were analyzed with a 16-genes NGS panel. RESULTS: In total, 284 germline mutations were identified in 161 patients. The most common mutations were in EPCAM (24.8%), MSH6 (24.2%), MLH1 (21.7%), and AXIN2 (21.7%). Germline mutations of AXIN2, POLE, POLD1, and TGFBR2 also resulted in EMAST and MSI. EMAST(+)/MSI-H tumors had a significant higher mutation number (205.9 ± 95.2 mut/MB) than tumors that were only EMAST(+) or MSI-H (118.6 ± 64.2 and 106.2 ± 54.5 mut/MB, respectively; both P < .001). In patients with AXIN2 germline mutations, the number of pathological somatic mutations in the tumors was significantly higher than those without AXIN2 germline mutations (176.7 ± 94.2 mut/MB vs 139.6 ± 85.0 mut/MB, P = .002). CONCLUSION: Next-generation sequencing could enhance the detection of familial CRC. The somatic mutation burden might result from not only the affected genes in germline mutations but also through the dysfunction of downstream effectors. The AXIN2 gene might associate with hypermutation in tumors. Further in vitro experiments to confirm the causal relationship is deserved.

Clinicopathological and Molecular Profiles of Sporadic Microsatellite Unstable Colorectal Cancer with or without the CpG Island Methylator Phenotype (CIMP).

BACKGROUND: The 5'-C-phosphate-G-3' island methylator phenotype (CIMP) is a specific phenotype of colorectal cancer (CRC) associated with microsatellite instability-high (MSI-high) tumors. METHODS: In this study, we determined the CIMP status using eight methylation markers in 92 MSI-high CRC patients after excluding five germline mismatch repair (MMR) gene mutations analyzed by next-generation sequencing (NGS) and confirmed by Sanger sequencing. The mutation spectra of 22 common CRC-associated genes were analyzed by NGS. RESULTS: Of the 92 sporadic MSI-high tumors, 23 (25%) were considered CIMP-high (expressed more than 5 of 8 markers). CIMP-high tumors showed proximal colon preponderance and female predominance. The mutation profiles of CIMP-high tumors were significantly different from those of CIMP-low or CIMP-0 tumors (i.e., higher frequencies of BRAF, POLD1, MSH3, and SMAD4 mutations but lower frequencies of APC, TP53, and KRAS mutations). Multivariate analysis demonstrated that tumor, node, metastasis (TNM) stage was the independent prognostic factor affecting overall survival (OS). Among the MSI-high cases, the CIMP status did not impact the outcome of patients with MSI-high tumors. CONCLUSIONS: Only TNM stage was a statistically significant predictor of outcomes independent of CIMP profiles in MSI-high CRC patients. Sporadic MSI-high CRCs with different mechanisms of carcinogenesis have specific mutation profiles and clinicopathological features.

SDF-1alpha G801A polymorphism predicts lymph node metastasis in stage T3 colorectal cancer.

BACKGROUND: The SDF-1/CXCR4 axis plays an important role in cancer metastasis. SDF1alpha genetic polymorphisms, including SDF1alpha-G801A, have been associated with increased cancer risk and may be predictive of distant metastasis. The present study compared the frequency of 6 SDF1alpha single-nucleotide polymorphisms (SNPs) in patients with colorectal cancer (CRC) with and without lymph node (LN) metastasis and determined whether fibroblasts with different SDF-1alpha genotypes influenced cancer cell proliferation and migration. METHODS: The study enrolled 424 patients with primary T3 stage CRC, with and without lymph node metastasis, and a median follow-up of 48 months. The polymerase chain reaction-sequence specific primers (PCR-SSP) technique was used to identify polymorphisms. Fibroblasts were harvested from 14 patients with stage II CRC and fibroblast-mediated enhancement of cancer cell proliferation and migration was evaluated. RESULTS: Only the SDF1alpha-G801A polymorphism was associated with LN metastasis. The frequency of GA/AA genotypes was significantly higher in patients with LN metastasis (54.8%) than in patients without LN metastasis (40.7%). In the latter group, disease-free survival was shorter in patients with the GA/AA genotype (74%) than in patients with the GG genotype (87.6%). In patients with LN metastasis, disease-free survival was similar regardless of genotype. Expression of SDF-1alpha mRNA in GA/AA fibroblasts was three times that in GG fibroblasts. GA/AA (but not GG) fibroblasts enhanced colon cancer cell (HCT116) proliferation and migration. These effects were blocked by an SDF-1alpha neutralizing antibody. CONCLUSIONS: The SDF1alpha-G801A polymorphism may increase expression of SDF-1alpha mRNA and be a predictive marker of lymph node metastasis in colorectal cancer.

Mitochondrial D-loop mutation is a common event in colorectal cancers with p53 mutations.

PURPOSE: p53 is the most frequently mutated gene in colorectal cancer. In mitochondria, p53 protein is involved in regulation of transcription/replication and maintenance of genomic stability. Our aim was to examine the relationship between p53, D-loop mutation, and mitochondrial DNA content in colorectal cancer (CRC). METHODS: A total of 194 patients with sporadic CRC without microsatellite instability who underwent surgery in Taipei Veterans General Hospital from January 1999 to December 2000 were included. The mitochondrial DNA content and D-loop mutation were quantified using real-time PCR and sequencing. RESULTS: D-loop mutation occurred at significantly higher frequency in tumors with p53 mutation (34/88; 38.6%) than in tumors without p53 mutation (23/106; 21.7%). The frequency of the decreased mtDNA content was significantly associated with TNM stage (p = 0.009) and p53 mutation (p = 0.036). The 5-year DFS rate was 39% in patients exhibiting tumors with decreased mtDNA content, and was significantly poorer in these patients than in those exhibiting tumors with normal level of mtDNA content (61%, p = 0.01). The presence of D-loop mutations had no effect on 5-year DFS rate. In multivariate survival analysis, TNM stage, and p53 mutation, but not decreased mtDNA content and D-loop instability, had significant impacts on prognosis. CONCLUSION: Change of mitochondrial DNA is a common event in colorectal cancer with p53 mutation, but is not associated with prognosis of CRC patients.

Clinicopathological and molecular differences in colorectal cancer according to location.

PURPOSE: The incidence, pathogenesis, molecular pathways, and outcomes of colorectal cancer vary depending on the location of the tumor. This study aimed to compare the difference in tumor characteristics and the outcome between right-sided colon cancer and left-sided colorectal cancer (LCRC). MATERIALS AND METHODS: A total of 1503 patients with colorectal cancer who underwent surgery at the Taipei Veterans General Hospital between 2000 and 2010 were enrolled in this study. Right-sided colon cancer was defined as cancers in the cecum, ascending colon, and transverse colon, while LCRC was defined as cancers in the splenic flexure colon, descending colon, sigmoid colon, and rectum. The endpoint was overall survival. The mutations were detected via polymerase chain reaction and MASS array. The prognostic value was determined using the log-rank test and the Cox regression analysis. RESULTS: A total of 407 and 1096 cases were classified as right-sided colon cancer and LCRC, respectively. Compared to patients with LCRC, those with right-sided colon cancer had more mucinous type cancer (7.4% vs. 3.5%), poorly differentiated tumor (11.5% vs. 3.6%), and advanced tumor-node-metastasis stage. The risk for peritoneal tumor seeding was higher in the right-sided colon cancer group (12.8% vs. 5.7%). Overall survival was better in LCRC than in right-sided colon cancer ( P=0.036). CONCLUSIONS: In our study, right-sided colon cancer had a more advanced tumor stage, a higher risk of peritoneal metastasis, and a poorer outcome than LCRC. Moreover, right-sided colon cancer had more gene mutations in BRAF, KRAS, SMAD4, TGF-ß, PIK3CA, PTEN, AKT1, and high microsatellite instability.