Combining Artificial Intelligence and Simplified Image Processing for the Automatic Detection of Mycobacterium tuberculosis in Acid-fast Stain: A Cross-institute Training and Validation Study.

Tuberculosis (TB) poses a significant health threat in Taiwan, necessitating efficient detection methods. Traditional screening for acid-fast positive bacilli in acid-fast stain is time-consuming and prone to human error due to staining artifacts. To address this, we present an automated TB detection platform leveraging deep learning and image processing. Whole slide images from 2 hospitals were collected and processed on a high-performance system. The system utilizes an image processing technique to highlight red, rod-like regions and a modified EfficientNet model for binary classification of TB-positive regions. Our approach achieves a 97% accuracy in tile-based TB image classification, with minimal loss during the image processing step. By setting a 0.99 threshold, false positives are significantly reduced, resulting in a 94% detection rate when assisting pathologists, compared with 68% without artificial intelligence assistance. Notably, our system efficiently identifies artifacts and contaminants, addressing challenges in digital slide interpretation. Cross-hospital validation demonstrates the system's adaptability. The proposed artificial intelligence-assisted pipeline improves both detection rates and time efficiency, making it a promising tool for routine pathology work in TB detection.

Colorectal neuroendocrine carcinoma and mixed neuroendocrine-non-neuroendocrine neoplasm: Prognostic factors and PD-L1 expression.

Colorectal neuroendocrine carcinoma (NEC) and mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) are rare malignancies with unclear boundaries and poor prognoses. Our study aimed to conduct a comparative analysis of these diseases, identify prognostic factors, and explore potential therapeutic targets. We collected and analyzed clinicopathological data of NEC and MiNEN in our hospital from 2011 to 2020. Immunohistochemical staining for PD-L1, BRAF V600E, and mismatch repair proteins was performed. We identified 14 NEC and 7 MiNEN cases. Demographic data, including median overall survival (17.1 months for NEC and 18.5 months for MiNEN), did not significantly differ. NEC showed a higher tendency to occur in the rectum and sigmoid colon (p = 0.025) and had fewer cases with metastatic adenocarcinoma components in lymph nodes (p = 0.009) compared to MiNEN. Adverse prognostic factors were age ≥70 years (p = 0.012), N2 nodal status (p = 0.032), and stage IV disease (p = 0.013) based on multivariate Cox regression analysis. We identified five PD-L1 positive cases, two BRAF V600E mutated cases, and one Lynch syndrome case with MSH2 and MSH6 loss. Patients with colorectal NEC or MiNEN exhibited poor survival rates. Adverse prognostic factors included older age, N2 nodal status, and distant metastasis. Potential therapeutic avenues such as immune checkpoint and BRAF inhibitors were suggested for patients with these carcinomas.

Assessment of Elastic Laminal Invasion Contributes to an Objective pT3 Subclassification in Colon Cancer.

The extent of tumor spread influences on the clinical outcome, and which determine T stage of colorectal cancer. However, pathologic discrimination between pT3 and pT4a in the eighth edition of the American Joint Committee on Cancer (AJCC)-TNM stage is subjective, and more objective discrimination method for deeply invasive advanced colon cancer is mandatory for standardized patient management. Peritoneal elastic laminal invasion (ELI) detected using elastic staining may increase the objective discrimination of deeply invasive advanced colon cancer. In this study, we constructed ELI study group to investigate feasibility, objectivity, and prognostic utility of ELI. Furthermore, pT classification using ELI was investigated based on these data. At first, concordance study investigated objectivity using 60 pT3 and pT4a colon cancers. Simultaneously, a multi-institutional retrospective study was performed to assess ELI's prognostic utility in 1202 colon cancer cases from 6 institutions. In the concordance study, objectivity, represented by κ, was higher in the ELI assessment than in pT classification. In the multi-institutional retrospective study, elastic staining revealed that ELI was a strong prognostic factor. The clinical outcome of pT3 cases with ELI was significantly and consistently worse than that of those without ELI. pT classification into pT3 without ELI, pT3 with ELI, and pT4a was an independent prognostic factor. In this study, we revealed that ELI is an objective method for discriminating deeply invasive advanced colon cancer. Based on its feasibility, objectivity, and prognostic utility, ELI can subdivide pT3 lesions into pT3a (without ELI) and pT3b (with ELI).

Surgical strategy for colorectal cancer with synchronous liver and extrahepatic metastases: A scoring system and decision tree model.

BACKGROUND: The role of hepatectomy in a specific group of patients with synchronous colorectal cancer with liver metastases (SCRLM) and synchronous extrahepatic disease (SEHD) is still unclear. The aim of this study was to evaluate the efficacy of liver surgery and define the selection criteria for surgical candidates in patients with SCRLM + SEHD. METHODS: Between July 2007 and October 2018, 475 patients with colorectal cancer with liver metastases (CRLM) who underwent liver resection were retrospectively reviewed. Sixty-five patients with SCRLM + SEHD were identified and included in the study. Clinical pathological data of these patients were analyzed to evaluate the influence on survival. Important prognostic factors were identified by univariate and multivariate analyses. The risk score system and decision tree analysis were generated according to the important prognostic factors for better patient selection. RESULTS: The 5-year survival rate of patients with SCRLM + SEHD was 21.9%. The most important prognostic factors were SCRLM number of more than five, site of SEHD other than the lung only, inability to achieve SCRLM + SEHD R0 resection, and BRAF mutation of cancer cells. The proposed risk score system and decision tree model easily discriminated between patients with different survival rates and identified the profile of suitable surgical patients. CONCLUSION: Liver surgery should not be a contraindication for patients with SCRLM + SEHD. Patients with complete SCRLM + SEHD R0 resection, SCRLM number less than or equal to five, SEHD confined to the lung only, and wild-type BRAF could have favorable survival outcomes. The proposed scoring system and decision tree model may be beneficial to patient selection in clinical use.

Radiomic features derived from pretherapeutic MRI predict chemoradiation response in locally advanced rectal cancer.

BACKGROUND: The standard treatment for locally advanced rectal cancer (LARC) is neoadjuvant concurrent chemoradiotherapy (CRT) followed by surgical excision. Current evidence suggests a favorable prognosis for those with pathological complete response (pCR), and surgery may be spared for them. We trained and validated regression models for CRT response prediction with selected radiomic features extracted from pretreatment magnetic resonance (MR) images to recruit potential candidates for this watch-and-wait strategy. METHODS: We retrospectively enrolled patients with LARC who underwent pre-CRT MR imaging between 2010 and 2019. Pathological complete response in surgical specimens after CRT was defined as the ground truth. Quantitative features derived from both unfiltered and filtered images were extracted from manually segmented region of interests on T2-weighted images and selected using variance threshold, univariate statistical tests, and cross-validation least absolute shrinkage and selection operator (Lasso) regression. Finally, a regression model using selected features with high coefficients was optimized and evaluated. Model performance was measured by classification accuracies and area under the receiver operating characteristic (AUROC). RESULTS: We extracted 1223 radiomic features from each MRI study of 133 enrolled patients. After tumor excision, 34 (26 %) of 133 patients had pCR in resected specimens. When 25 image-derived features were selected from univariate analysis, classification AUROC was 0.86 and 0.79 with the addition of six clinical features on the hold-out internal validation dataset. When 11 image-derived features were used, the optimized linear regression model had an AUROC value of 0.79 and 0.65 with the addition of six clinical features on the hold-out dataset. Among the radiomic features, texture features including gray level variance, strength, and cluster prominence had the highest coefficient by Lasso regression. CONCLUSION: Radiomic features derived from pretreatment MR images demonstrated promising efficacy in predicting pCR after CRT. However, radiomic features combined with clinical features did not result in remarkable improvement in model performance.

Perianal Paget's Disease: The 17-Year-Experience of a Single Institution in Taiwan.

AIM: To determine the incidence, prognosis, and immunophenotypes (CK7, CK20, CDX2, and GCDFP-15) of primary or secondary perianal Paget's diseases (PPDs). METHODS: Twenty-three PPD patients were recruited, including 10 primary and 13 secondary PPDs. Immunophenotypes of PPD were analyzed. RESULTS: In 23 PPD patients, 14 (60.9%) were male and the median age was 75 years. Three (13.0%, 2 primary and 1 secondary PPDs) had recurrence and two (8.7%, both primary PPDs) had invasive PPDs. The colorectal cancers (CRCs) in secondary PPD cases were located in anorectal area for 9 patients while 4 were located in the rectum; 5, 2, 4, and 2 were in stages I, II, III, and in uncertain stage, respectively. The distant metastasis rates of CRC in the secondary PPD patients during follow-up were 40% (2/5), 0% (0/2), and 50% (2/4) for stages I, II, and III, respectively. Other synchronous or metachronous malignancies included cholangiocarcinoma, urothelial carcinoma, anorectal small-cell carcinoma, and unknown hepatic malignancy. One primary PPD patient died from the metastases of invasive Paget's disease while 3 secondary PPD patients died from the metastases of CRCs during follow-up. Immunohistochemical staining showed CK7 (7/10 and 6/13), CK20 (6/10 and 10/13), CDX2 (6/10 and 12/13), and GCDFP-15 (3/10 and 0/13) positivities in primary and secondary PPD patients, respectively. The immunophenotypes were not statistical significantly related to synchronous CRC (P = 0.402, 0.650, 0.127, and 0.068 for CK7, CK20, CDX2, and GCDFP-15, respectively). CONCLUSIONS: The incidence of concurrent CRC in PPD patients is not low. An adequate survey for CRC should be considered for PPD patients at initial diagnosis. In this series of study, stage I CRC with PPD would have a higher metastatic rate, thus indicating aggressive treatment and follow-up. The CK7, CK20, CDX2, and GCDFP-15 immunostaining results for the PPD patients were not predictive of primary or secondary type.

Staging of colorectal cancers based on elastic lamina invasion.

Peritoneal involvement in colorectal cancer (CRC) has prognostic significance and is an important parameter in pathologic tumor staging. Restaging of tumors based on peritoneal elastic lamina invasion (ELI) has prognostic significance in CRCs classified as pathologic stage 3 tumors without regional lymph node metastasis (pT3N0). However, limited data on the significance of ELI in patients with node-positive disease are available. We applied elastic stain to one block per case for 141 consecutive patients with pT3N1M0 CRCs. The elastic lamina was identified in only 62 cases (44%), of which 39 (27.6%) displayed ELI. The ELI+ group was associated with a significantly worse ( 0.;P < .001) 5-year disease-free survival (5-year DFS, 48.7%) and 5-year overall survival (5-year OS, 61.4%) compared with the ELI- (5-year DFS, 73.9%; OS, 95.7%) and no elastic lamina (5-year DFS, 79.5%; OS, 85.7%) groups. Comparison of outcomes in cases with pT3N1M0 with peritoneal ELI and pT4aN1M0 tumors (based on the original pathologic assessment without the use of elastic staining) showed no significant differences in the 5-year DFS (P = .47) and OS (P = .65). These findings suggest that ELI is a significant prognostic marker and that elastic staining should be considered for routine use in pT3 CRCs in a node-positive setting. Upstaging of pT3 tumors with ELI should be considered in the future iterations of the American Joint Committee on Cancer/Union for International Cancer Control tumor-node-metastasis staging system for CRC.

Mutation spectra of RAS gene family in colorectal cancer.

BACKGROUND: The clinicopathologic features and frequency of KRAS mutations in colorectal cancer (CRC) patients have been reported; however, the characteristics and impact of NRAS and HRAS mutations on the survival of CRC patients have seldom been addressed. METHODS: Under institutional review board approval, 1,519 CRC patients who underwent surgery were enrolled. Mutation status of RAS was determined by polymerase chain reaction and mass spectrophotometry. RESULTS: The frequency of KRAS, NRAS, and HRAS mutations was 39.6%, 4.3%, and 1.7%, respectively. The KRAS mutation was associated with fewer left-sided tumors, fewer poor differentiated tumors, more mucin component, and less lymphovascular invasion. The NRAS or HRAS mutations were not associated with any of the clinicopathologic features examined. After univariate analysis, only NRAS mutation was associated with patients' overall and disease-free survival. However, the association of NRAS with patients' overall and disease-free survival disappeared after stepwise elimination. CONCLUSIONS: This study demonstrates the clinicopathologic characteristics of CRC patients with RAS mutations. Patients with NRAS mutation tended to have worse outcomes.

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.

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.

Comparison of the Clinical Characteristics and Outcome of Benign and Malignant Eyelid Tumors: An Analysis of 4521 Eyelid Tumors in a Tertiary Medical Center.

We retrospectively reviewed the clinical features and outcome of benign and malignant eyelid tumors from 1995 to 2015 in a tertiary medical center. Among 4,521 histologically confirmed eyelid tumors, 4,294 (95.0%) were benign tumors and 227 (5.0%) were malignant tumors. The mean age at diagnosis was significantly higher in patients with malignant lid tumors than those with benign lid tumors (72.5 and 55.4 years, resp., p < 0.001). The most common benign eyelid tumors were intradermal nevus (21.1%), followed by seborrheic keratosis (12.6%) and xanthelasma (11.2%). The most common malignant eyelid tumors were basal cell carcinomas (57.8%), followed by sebaceous gland carcinomas (21.1%) and squamous cell carcinomas (10.1%). There was a relative male predominance (63.4% and 49.2%, resp., p < 0.001) and higher recurrence rate (11.9% and 4.4%, resp., p < 0.001) in malignant lid tumors as compared with those of benign lid tumors. Twenty-two patients (9.7%) received orbital exenteration/enucleation. Eight patients (3.5%) with malignant lid tumors died of disease. Patients with eyelid melanoma were associated with a high mortality rate (25.0%). It is important to differentiate between benign and malignant eyelid tumors, because they may cause cosmetic disfigurement and severe morbidity, especially in those with malignant eyelid tumors.

Integrating a Web-Based Whole-Slide Imaging System and Online Questionnaires in a National Cytopathology Peer Comparison Educational Program in Taiwan.

OBJECTIVE: In a peer comparison educational program, transferring glass slides between laboratories and collecting responses are time- and cost-consuming. Integrating a web-based whole-slide imaging (WSI) system and online questionnaires may serve as a promising solution. STUDY DESIGN: Five gynecologic Papanicolaou-stained smears and 5 nongynecologic slides were selected. The 10 whole-slide images were acquired by a Leica SCN-400 system and released via an Aperio eSlide Manager. Online questionnaires generated by Google Forms with access to the 10 whole-slide images were released to all the practitioners in Taiwan by e-mail. After closing the program, an online posttest feedback survey was conducted. RESULTS: A total of 302 participants joined the gynecologic test, and 291 joined the nongynecologic test. The correct interpretation rates were 81.8-93.7% in the former and 28.5-93.1% in the latter. In the posttest feedback survey, there were 63.2% of the participants reporting first-time WSI experience, and 97.9% of them said they would like to participate in a similar program again. CONCLUSION: Integrating a web-based WSI system and online questionnaires is an easy method to access nationwide practitioners. Participants can make interpretations using WSI even without prior experience. The model is valuable for those who want to initiate a large-scale cytopathology peer comparison educational program.

Adenosquamous Carcinoma of the Esophagus and Esophagogastric Junction: Clinical Manifestations and Treatment Outcomes.

BACKGROUND/AIMS: The aim of this study is to understand the clinicopathological manifestations, treatment, and prognostic factors of adenosquamous carcinoma (ASC) of the esophagus and esophagogastric junction, a rare malignancy. METHODS: From 1981 to 2011, 26 out of 4704 patients (23 males, 3 females; mean age: 65.8 years) with ASC of the esophagus and esophagogastric junction who received surgical resection were analyzed. RESULTS: Only one (4.2%) patient was diagnosed with ASC by preoperative endoscopic biopsy. Three patients received Ivor-Lewis operation with intrathoracic esophagogastrostomy, seven received gastrectomies, and the other 16 underwent transthoracic esophagectomies. Median follow-up time was 30.6 months (interquartile range, 17.9-95.1 months). At study end, there were 12 (46.2%) patients with tumor relapse, all within 3 years postoperatively. The 5-year disease-free survival (DFS) rate was 46.2%. Tumor length and no postoperative adjuvant treatment were the independent prognostic factors for DFS. The 5-year overall survival (OS) rate was 30.8%. On multivariate analysis, the resection type, tumor length, and perineural invasion were independent prognostic factors for OS. CONCLUSION: ASC is a rare cell type of the esophagus and esophagogastric junction that is easily misdiagnosed at endoscopic biopsy. OS rate was no worse than that reported for squamous cell carcinoma (SCC). Tumor length was the independent prognostic factor for both DFS and OS.

Clinicopathological analysis of colorectal carcinoid tumors and patient outcomes.

BACKGROUND: Colorectal carcinoid tumors are often described as being low-grade malignant. The objective of the current study was to address the clinicopathological features and outcomes of patients with colorectal carcinoid tumors. METHODS: A total of 63 patients with colorectal carcinoid tumors were identified and evaluated using surgical pathology files and medical records between January 2000 and June 2012 at the Veterans General Hospital, Taipei, Taiwan. RESULTS: The median age of the 63 patients was 57.0 years; 38 (60.3%) were male and 25 (39.7%) female. The rectum was the most common tumor site (90.5%). Tumor size was 10.8±7.4 mm, ranging from 2 to 50 mm in diameter. There were 40 patients (63.5%) who received endoscopic treatment for a tumor size of 7.7±4.0 mm, 15 (23.8%) who underwent transanal excision for a mean size of 9.2±4.5 mm and eight (12.7%) who underwent radical surgical resection (mean size: 29.5±13.0 mm). Lymph node metastasis was significantly associated with tumor size. Totally distant metastases (liver) were demonstrated in four (6.3%), patients with mean tumor size of 31.3±9.4 mm (20 to 50 mm). The extent of the disease was associated with survival and the five-year overall survival rate was 92.1%. CONCLUSIONS: With widespread colorectal cancer screening, heightened awareness and improved diagnostic modalities, the incidence of colorectal carcinoid tumors will continue to increase. We demonstrated that small-sized colorectal carcinoid tumors and those localized in the mucosa or submucosa may be safely and effectively removed via endoscopic or transanal local excision.

Assessment of the value of carcinoembryonic antigen reduction ratio as a prognosis factor in rectal cancer.

BACKGROUND: Carcinoembryonic antigen (CEA) is the most widely used tumor marker for colorectal cancer. This study aimed to investigate the role of CEA reduction ratio after preoperative chemoradiotherapy (CRT). METHODS: We enrolled 284 patients who underwent preoperative CRT followed by radical surgical resection. Patients were divided into 3 groups: serum CEA levels before CRT (pre-CRT CEA) less than 5 ng/mL (group 1); pre-CRT CEA of 5 ng/mL or more with CEA reduction ratio of 50% or more (group 2); and pre-CRT CEA of 5 ng/mL or more with CEA reduction ratio less than 50% (group 3). RESULTS: The 5-year disease-free survival (DFS) rate was not different between groups 1 (71.8%) and 2 (69.4%) but was significantly lower in group 3 (49.5%). CEA group, lymph node status after CRT (ypN) stage, and histologic type were independent prognostic factors for DFS on multivariate analysis. CONCLUSIONS: CEA reduction ratio might be an independent prognostic factor for DFS in rectal cancer patients treated with preoperative CRT and radical surgery.

Morphology and natural history of familial adenomatous polyposis-associated dysplastic fundic gland polyps.

AIMS: Most patients with familial adenomatous polyposis (FAP) develop gastric fundic gland polyps, with many displaying low-grade dysplasia. This study evaluates the natural history and morphological phenotype of dysplasia in FAP-associated fundic gland polyps. METHODS AND RESULTS: Patients with FAP and dysplastic fundic gland polyps (n = 24) were identified. Twenty-two of 24 FAP-associated dysplastic fundic gland polyps showed a gastric phenotype and two had mixed phenotype. During a mean 6.1-year follow-up (range 0.8-12.6 years) and 5.7 endoscopies (range 2-22), one patient (4%) was diagnosed with a fundic gland polyp with high-grade dysplasia, while 23 patients (96%) in this cohort had either no dysplasia or persistent low-grade dysplasia. Contemporary patients with sporadic fundic gland polyps with low-grade dyplasia had similar morphology and outcomes to the FAP-associated fundic gland polyp cohort. Dysplasia in fundic gland polyps (FAP-associated and sporadic) was associated less frequently with intestinal phenotype, high-grade dysplasia and the finding of concurrent or subsequent carcinoma compared to contemporary patients with sporadic gastric dysplasia not occurring in fundic gland polyps. CONCLUSIONS: This cohort of patients with FAP-associated dysplastic fundic gland polyps rarely developed high-grade dysplasia and gastric adenocarcinoma was absent.

Mutational and clinical predictors of pathologic complete response in the treatment of locally advanced rectal cancer.

PURPOSE: Preoperative chemoradiation (CRT) for locally advanced rectal adenocarcinoma achieves pathologic complete response (pCR) in 8-20% of patients. Mutations in critical cancer genes may contribute to lack of pCR. We retrospectively evaluated our institutional experience to determine potential mutational and clinical predictors of pCR in patients treated with CRT. METHODS: Patients with locally advanced rectal adenocarcinoma treated with preoperative CRT (n = 79) were identified. A clinical cancer genotyping assay evaluated 140 hotspot mutation sites across 15 cancer genes in 47 patients with sufficient tissue. Mutational profiles were compared in pre- and post-CRT specimens and with pCR rate. Clinical variables were evaluated using logistic regression. RESULTS: Genotyping identified mutations in KRAS (43%), APC (17%), BRAF (4%), NRAS (4%), PIK3CA (4%), and TP53 (11%). In the entire cohort, 21.5% had a pCR. No patients with BRAF, NRAS, APC, or TP53 achieved a pCR. pCR rate was 23.5% (4/17) in wild-type tumors versus 3.3% (1/30) in those with a mutation. There was no difference in the mutation rates in pre- versus post-CRT specimens. On univariate analysis, clinical predictors of pCR included post-RT carcinoembriogenic antigen level of ≤2.5 and smaller tumor size. No patients with a pCR developed recurrence. CONCLUSION: Patients without mutations in commonly mutated cancer genes may be associated with a higher likelihood of having a pCR after preoperative CRT. This should be confirmed in a prospective study.

The Number of Risk Factors Determines the Outcome Of Stage II Colorectal Cancer Patients.

BACKGROUND/AIMS: We evaluated the prognostic significance of clinicopathologic features recommended by the majority of guidelines for identifying high-risk stage it colon cancer patients. METHODOLOGY: We enrolled 665 stage II colorectal cancer patients at Taipei Veterans General Hospital in 2002-2006. Patients who received preoperative or postoperative chemotherapy were excluded (124). The measured endpoint was disease-free survival. RESULTS: Of 541 patients, 59 showed stage T4 tumors; 35, lymphovascular invasion; 19, poor differentiation, and 251, carcinoembryonic antigen levels of > 5 ng/mL; 53 underwent emergent operations. Colorectal cancer recurred in 84 patients. The 5-year disease-free survival rate was 84.5%. Univariate and multivariate analyses revealed 3 independent factors affecting the prognosis significantly tumor stage T4, high carcinoembryonic antigen level, and presence of lymphovascular invasion. Considering the cumulative effect of risk factors, the 5-year disease-free survival rate of patients with tumors without any risk factor was 90.2%, which was significantly better than that of patients with 1 or 2 risk factors (82.3%, 61.6%). CONCLUSIONS: Stage II colorectal cancer patients had excellent outcome. Ad juvant chemotherapy may be warranted for patients with multiple risk factors.

Impact of KRAS mutation on outcome of patients with metastatic colorectal cancer.

BACKGROUND/AIMS: KRAS mutation is present in 30%-50% of colorectal cancers and is associated with the inefficacy of anti-epidermal growth factor receptor therapy, while the impact of KRAS on survival is seldom discussed. The aim of this study was to elucidate the impact of KRAS status on the survival of patients with metastatic colorectal cancer. METHODOLOGY: Two hundred and one patients with metastatic colorectal cancer were enrolled. Amplification and sequencing of the KRAS gene were performed, with the overall survival according to KRAS status analyzed. RESULTS: KRAS mutations were present in 72 (35.8%) of patients, including 55 (27.3%) codon 12 mutations and 17 (8.5%) codon 13 mutations. Lymphovascular invasion (hazard ratio 1.841, 95% confidence interval 1.043-3.247, p = 0.035) and KRAS mutation (hazard ratio 1.919, 95% confidence interval 1.104-3.333, p = 0.021) were independent prognostic factors for overall survival. The median overall survival for patients with KRAS mutation at codon 12 was 27.3 months, and was similar to those with KRAS mutation at codon 13 (20.4 months, p = 0.628). CONCLUSIONS: KRAS mutation is a poor prognostic factor in patients with metastatic colorectal cancer. In KRAS mutation metastatic colorectal cancer, mutation at codon 12 or at codon 13 had no relationship with prognosis.