Treatment Decision for Locally Resected T1 Colorectal Carcinoma-Verification of the Japanese Guideline Criteria for Additional Surgery Based on Long-Term Clinical Outcomes.

INTRODUCTION: To verify the value of the pathological criteria for additional treatment in locally resected pT1 colorectal carcinoma (CRC) which have been used in the Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines since 2009. METHODS: We enrolled 4,719 patients with pT1 CRC treated at 27 institutions between July 2009 and December 2016 (1,259 patients with local resection alone [group A], 1,508 patients with additional surgery after local resection [group B], and 1,952 patients with surgery alone [group C]). All 5 factors of the JSCCR guidelines (submucosal resection margin, tumor histologic grade, submucosal invasion depth, lymphovascular invasion, and tumor budding) for lymph node metastasis (LNM) had been diagnosed prospectively. RESULTS: Any of the risk factors were present in 3,801 patients. The LNM incidence was 10.3% (95% confidence interval 9.3-11.4) in group B/C patients with risk factors, whereas it was 1.8% (95% confidence interval 0.4-5.2) in those without risk factors ( P < 0.01). In group A, the incidence of recurrence was 3.4% in patients with risk factors, but it was only 0.1% in patients without risk factors ( P < 0.01). The disease-free survival rate of group A patients classified as risk positive was significantly worse than those of groups B and C patients. However, the 5-year disease-free survival rate in group A patients with no risk was 99.2%. DISCUSSION: Our large-scale real-world multicenter study demonstrated the validity of the JSCCR criteria for pT1 CRC after local resection, especially regarding favorable outcomes in patients with low risk of LNM.

How Does Omitting Additional Surgery After Local Excision Affect the Prognostic Outcome of Patients With High-risk T1 Colorectal Cancer?

OBJECTIVE: To investigate how omitting additional surgery after local excision (LE) affects patient outcomes in high-risk T1 colorectal cancer (CRC). BACKGROUND: It is debatable whether additional surgery should be performed for all patients with high-risk T1 CRC regardless of the tolerability of invasive procedures. METHODS: Patients who had received LE for T1 CRC at the Japanese Society for Cancer of the Colon and Rectum institutions between 2009 and 2016 were analyzed. Those who had received additional surgical resection and those who did not were matched one-on-one by the propensity score-matching method. A total of 401 propensity score-matched pairs were extracted from 1975 patients at 27 Japanese Society for Cancer of the Colon and Rectum institutions and were compared. RESULTS: Regional lymph node metastasis was observed in 31 (7.7%) patients in the LE + surgery group. Comparatively, the incidence of oncologic adverse events was low in the LE-alone group, such as the 5-year cumulative risk of local recurrence (4.1%) or overall recurrence (5.5%). In addition, the difference in the 5-year cancer-specific survival between the LE + surgery and LE-alone groups was only 1.8% (99.7% and 97.9%, respectively), whereas the 5-year overall survival was significantly lower in the LE-alone group than in the LE + surgery group [88.5% vs 94.5%, respectively ( P = 0.002)]. CONCLUSIONS: Those who had decided to omit additional surgery at the dedicated center for CRC treatment presented a small number of oncologic events and a satisfactory cancer-specific survival, which may suggest an important role of risk assessment regarding nononcologic adverse events to achieve a best practice for each individual with high-risk T1 tumors.

Annual report on National Clinical Database 2020 for gastroenterological surgery in Japan.

Aim: The National Clinical Database (NCD) of Japan is a nationwide data entry system for surgery, and it marked its 10th anniversary in 2020. The aim was to present the 2020 annual report of gastroenterological surgery of the NCD. Methods: The data of the surgical procedures stipulated by the training curriculum for board-certified surgeons of the Japanese Society of Gastroenterological Surgery in the NCD from 2011 to 2020 were summarized. Results: In total, 5 622 845 cases, including 593 088 cases in 2020, were extracted from the NCD. The total number of gastroenterological surgeries increased gradually in these 10 years, except for the year 2020 due to the COVID-19 pandemic. The annual number of surgeries of each organ, except the pancreas and liver, decreased by 0.4%-13.1% in 2020 compared to 2019. The surgical patients were consistently aging, with more than 20% of all gastroenterological surgeries in 2020 involving patients aged 80 years or older. The participation of board-certified surgeons increased for each organ (75.9%-95.7% in 2020). The rates of endoscopic surgery also increased constantly. Although the incidences of postoperative complications of each organ increased by 0.7%-7.9% in these 10 years, postoperative mortality rates decreased by 0.2%-1.5%. Conclusions: We present here the short-term outcomes of each gastroenterological operative procedure in 2020. This review of the 10-years of NCD data of gastroenterological surgery revealed a consistent increase of the number of surgeries (except for in 2020), especially endoscopic procedures, and aging of the Japanese population. The good safety of Japanese gastroenterological surgeries was also indicated.

Prognostic impact of desmoplastic reaction in esophageal squamous cell carcinoma patients with neoadjuvant therapy.

AIM: This study aimed to examine the prognostic value of desmoplastic reaction (DR) in esophageal squamous cell carcinoma (ESCC), particularly in patients who received neoadjuvant therapy, such as chemotherapy (NAC) or chemoradiotherapy (NACRT). METHOD: In total, 153 patients with pStage II/III ESCC were included in this study. Ninety-one patients received neoadjuvant therapy (NAC, 70; NACRT, 21). Patients were classified according to three DR categories based on the presence of keloid-like collagen and/or myxoid stroma. RESULTS: In total, 50, 50, and 53 patients were classified as having mature, intermediate, and immature DR, respectively. The weighted kappa coefficient was 0.623 in the patients with preoperative treatments and 0.782, in those without. The 5-year disease-specific survival (DSS) rates in patients with intermediate/immature DR was significantly worse than those with mature DR (40.7% vs. 73.3%, p < 0.001). Similarly, the 5-year DSS rate in patients with intermediate/immature DR was significantly worse than those with mature DR in a study of patients who received neoadjuvant therapy (46.7% vs. 71.2%, p = 0.009). Multivariate analysis revealed that DR (hazard ratio [HR]: 3.15, 95% confidence interval [CI] 1.58-6.27, p = 0.001), along with N factors, was an independent risk factor for DSS. Moreover, multivariate analysis of patients who received neoadjuvant therapy revealed only DR (HR: 2.47, 95% CI 1.02-5.96, p = 0.045) as independent risk factors for DSS. CONCLUSION: The DR classification was a valuable prognostic factor not only in the ESCC patients without neoadjuvant therapy but also in those with neoadjuvant therapy.

Nomogram as a novel predictive tool for lymph node metastasis in T1 colorectal cancer treated with endoscopic resection: a nationwide, multicenter study.

BACKGROUND AND AIMS: Since 2009, the Japanese Society for Cancer of the Colon and Rectum guidelines have recommended that tumor budding and submucosal invasion depth, in addition to lymphovascular invasion and tumor grade, be included as risk factors for lymph node metastasis (LNM) in patients with T1 colorectal cancer (CRC). In this study, a novel nomogram was developed and validated by usirge-scale, real-world data, including the Japanese Society for Cancer of the Colon and Rectum risk factors, to accurately evaluate the risk of LNM in T1 CRC. METHODS: Data from 4673 patients with T1 CRC treated at 27 high-volume institutions between 2009 and 2016 were analyzed for LNM risk. To prepare a nonrandom split sample, the total cohort was divided into development and validation cohorts. Pathologic findings were extracted from the medical records of each participating institution. The discrimination ability was measured by using the concordance index, and the variability in each prediction was evaluated by using calibration curves. RESULTS: Six independent risk factors for LNM, including submucosal invasion depth and tumor budding, were identified in the development cohort and entered into a nomogram. The concordance index was .784 for the clinical calculator in the development cohort and .790 in the validation cohort. The calibration curve approached the 45-degree diagonal in the validation cohort. CONCLUSIONS: This is the first nomogram to include submucosal invasion depth and tumor budding for use in routine pathologic diagnosis based on data from a nationwide multi-institutional study. This nomogram, developed with real-world data, should improve decision-making for an appropriate treatment strategy for T1 CRC.

Deep-learning-based classification of desmoplastic reaction on H&E predicts poor prognosis in oesophageal squamous cell carcinoma.

AIMS: Desmoplastic reaction (DR) categorisation has been shown to be a promising prognostic factor in oesophageal squamous cell carcinoma (ESCC). The usual DR evaluation is performed using semiquantitative scores, which can be subjective. This study aimed to investigate whether a deep-learning classifier could be used for DR classification. We further assessed the prognostic significance of the deep-learning classifier and compared it to that of manual DR reporting and other pathological factors currently used in the clinic. METHODS AND RESULTS: From 222 surgically resected ESCC cases, 31 randomly selected haematoxylin-eosin-digitised whole slides of patients with immature DR were used to train and develop a deep-learning classifier. The classifier was trained for 89 370 iterations. The accuracy of the deep-learning classifier was assessed to 30 unseen cases, and the results revealed a Dice coefficient score of 0.81. For survival analysis, the classifier was then applied to the entire cohort of patients, which was split into a training (n = 156) and a test (n = 66) cohort. The automated DR classification had a higher prognostic significance for disease-specific survival than the manually classified DR in both the training and test cohorts. In addition, the automated DR classification outperformed the prognostic accuracy of the gold-standard factors of tumour depth and lymph node metastasis. CONCLUSIONS: This study demonstrated that DR can be objectively and quantitatively assessed in ESCC using a deep-learning classifier and that automatically classed DR has a higher prognostic significance than manual DR and other features currently used in the clinic.

Desmoplastic reactions and epithelial-mesenchymal transition proteins in stages II and III colorectal cancer: association with and prognostic value for disease-free survival.

Recent study has shown that there is a close association of desmoplastic reactions (DRs) with the survival of patient with colorectal cancer (CRC). Here, we examined the correlation of DR classification with disease-free survival and overall survival of CRC. Moreover, we also investigated the association of the histological transition of the DR with the expression of cancer-associated fibroblast (CAF)- and epithelial-mesenchymal transition (EMT)-related proteins in CRC in stages II and III. We examined 157 cases of stage II CRC and 163 cases in stage III. We classified DRs into mature, intermediate, and immature types and examined the correlation of the DR patterns with patient survival. Next, the expression of CAF- and EMT-related markers was examined in CRC samples using immunohistochemistry. In stage II CRC, we found a significant correlation of disease-free survival with DR subtype (immature vs mature) in univariate and multivariate analyses. In stage III CRC, however, such association was not identified. Finally, the DR was closely associated with two EMT-related markers in stages II and III CRC. Our findings suggest that classification of the DR may help to predict patient prognosis in CRC. Furthermore, classification of the DR is correlated with the expression of EMT-related proteins.

Proposal for a tumor budding predictive score derived from endoscopic biopsy samples in colorectal cancer.

BACKGROUND: In colorectal cancer, tumor budding is highlighted as both a prognostic indicator and a predictor of chemosensitivity. However, tumor budding has a serious drawback because of unattainable preoperative assessment, thereby, making it not applicable to decision-making on treatment strategies. Recently, high expressions of seven genes (i.e., MSLN, SLC4A11, WNT11, SCEL, RUNX2, MGAT3, and FOXC1) were shown to be associated with high-budding colorectal cancers. This study aimed to propose a budding prediction system using selected RNAs extracted from biopsy specimens. METHODS: The RNA expression levels in 86 surgically resected samples and in 104 samples obtained by colonoscopy before surgery were investigated. RESULTS: The tumor surface expressions of four exclusive genes (i.e., MSLN, SLC4A11, SCEL, and MGAT3) were correlated with the tumor budding grade. Subsequently, the logit P value calculated by multiple logistic regression analysis using the four surface gene expressions was set as the following budding predictive score: Logit (P) = - 0.55 + 0.27*MSLN + 0.16*SLC4A11 + 0.06*MGAT3 + 0.21*SCEL. The effectiveness of the model using colorectal cancer biopsy samples was well corroborated prospectively. CONCLUSION: The budding predictive score that we developed using endoscopic biopsy specimens was clarified to have a high potential for preoperative use.

Cancer-associated fibroblasts at the unfavorable desmoplastic stroma promote colorectal cancer aggressiveness: Potential role of ADAM9.

The tumor microenvironment plays a key role in cancer aggressiveness. Desmoplastic reaction (DR), morphologically classified as Mature, Intermediate and Immature types, has previously been shown to be highly prognostic in colorectal cancer (CRC) and it consists to a large extent of cancer-associated fibroblasts (CAFs). The aim of our study was to characterize the molecular background of DR and understand the effects of CAFs in tumor aggressiveness. The prognostic significance of DR was initially examined in 1497 patients. Then CAFs originating from patient tissues with different DR types were isolated and their impact on tumor growth was examined both in vitro and in vivo. DR was shown to be highly prognostic, with patients within the Immature DR group conferring the worst relapse-free survival. The conditioned media of CAFs from tumor with Immature-type DR (CAFsImmature ) significantly increased proliferation and migration of CRC cell lines and growth of CRC-derived organoids compared to that of CAFs from Mature-type DR (CAFsMature ). Subcutaneous or orthotopic implantation of CRC cells together with CAFsImmature in mice significantly promoted tumor growth and dissemination compared to implantation with CAFsMature . Systematic examination of the expression of "a disintegrin and metalloproteinases" (ADAMs) in CAFs isolated from CRC tissues showed that the secreted isoform of ADAM9 (ADAM9s) was significantly higher in CAFsImmature than in CAFsMature . Knockdown of ADAM9s in CAFsImmature abrogated the promoting effects on CRC cell proliferation and migration. CAFs-derived ADAM9s is implicated in deteriorating survival in CRC patients with Immature-type DR by increasing tumor cell proliferation and dissemination.

How has the COVID-19 pandemic affected gastrointestinal surgery for malignancies and surgical infections?

The coronavirus disease 2019 (COVID-19) pandemic has affected infection control and prevention measures. We investigated the impact of the COVID-19 pandemic on postoperative infections and infection control measures in patients underwent gastrointestinal surgery for malignancies. We retrospectively evaluated changes in clinicopathological features, frequency of alcohol-based hand sanitizer use, frequency of postoperative complications, and microbial findings among our patients in February-May in 2019 (Control group) and 2020 (Pandemic group), respectively. Surgical resection in pathological stage III or IV patients was more frequently performed in the Pandemic group than in the Control group (P = 0.02). The total length of hospitalization and preoperative hospitalization was significantly shorter in the Pandemic group (P = 0.01 and P = 0.008, respectively). During the pandemic, hand sanitizer was used by a patients for an average of 14.9±3.0 times/day during the pandemic as opposed to 9.6±3.0 times/day in 2019 (p<0.0001). Superficial surgical site infection and infectious colitis occurred less frequently during the pandemic (P = 0.04 and P = 0.0002, respectively). In Pandemic group, Enterobacter, Haemophilus, and Candida were significantly decreased in microbiological cultures (P < 0.05, P < 0.05, P = 0.02, respectively) compared with Control group. Furthermore, a significant decrease in Streptococcus from drainage cultures was observed in the Pandemic group (P < 0.05). During the COVID-19 pandemic, a decrease in nosocomial infections was observed in the presence of an increase in alcohol-based hand sanitizer use.

Expression Patterns of Microenvironmental Factors and Tenascin-C at the Invasive Front of Stage II and III Colorectal Cancer: Novel Tumor Prognostic Markers.

BACKGROUND: Biological markers expressed in cancer cells and the surrounding cancer-associated fibroblasts (CAF) can be used for prediction of patient prognosis in colorectal cancer (CRC). Here, we used immunohistochemical techniques to evaluate cancer cells' expression of specific biomarkers that are closely associated with neoplastic progression. METHODS: Immunohistochemical markers included Ki-67, p53, ß-catenin, MMP7, E-cadherin and HIF1-α. We also characterized microenvironmental markers expressed by CAF, including expression of α-smooth muscle actin, CD10, podoplanin, fibroblast specific protein 1, platelet derived growth factor ß, fibroblast association protein, tenascin-C (TNC), ZEB1 and TWIST1. The study population consisted of 286 CRC patients with stage II and III disease. Stage II and III CRC were divided into a first and a second cohort (for validation). The CRCs were stratified using cluster analysis. To identify the utility of prognostic markers in stage II and III CRC, univariate and multivariate analyses were performed in both cohorts. RESULTS: Stage II and III CRCs were stratified into 3 subgroups. Specific subgroups were significantly correlated to disease-free survival using univariate and multivariate analyses in the first cohort. High expression of TNC was identified as a single prognostic marker in both cohorts by univariate and multivariate analyses. CONCLUSIONS: We suggest that the presence of a specific subgroup defined by multiple markers can be used for prediction of CRC outcome in stages II and III. In addition, we showed that high expression of TNC was correlated with a poorer prognosis in stages II and III of CRC.

Mesothelin Expression is Correlated with Chemoresistance in Stage IV Colorectal Cancer.

BACKGROUND: Mesothelin (MSLN) is a cell-surface glycoprotein present on mesothelial cells; its expression in several epithelial cancers generally portends an unfavorable prognosis. We investigated MSLN as a surrogate chemopredictive biomarker and examined the impact of MSLN expression in stage IV colorectal cancer (CRC). METHODS: We recruited 254 patients with CRC who received systemic chemotherapy following primary tumor resection between 2000 and 2019. Resected specimens were immunostained for MSLN and stratified by MSLN expression. The associations of tumor MSLN expression with tumor response in metastatic lesions and survival were evaluated. RESULTS: Of the 247 patients with stage IV CRC, 41 (16.1%) and 213 (83.9%) had high and low MSLN expression, respectively. Based on the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria, the investigator-assessed objective response rate was 22.0% in the high MSLN expression group and 45.5% in the low MSLN expression group (p = 0.0050). The disease control rates in these groups were 65.9% and 85.9%, respectively (p = 0.00019). In the patients with high MSLN expression, the conversion rate among those with initially unresectable metastases was 0% versus 14% in the patients with low MSLN expression (p = 0.0053). The median overall survival (OS) was 1.5 years (95% confidence interval [CI] 1.1-2.8) in the high MSLN expression group versus 2.6 years (95% CI 2.2-3.0) in the low MSLN expression group. The 3-year OS rates in these groups were 23.5 and 41.5%, respectively (p = 0.0120). CONCLUSIONS: High MSLN expression is correlated with chemoresistance and poor prognoses in stage IV CRC.

Erratum: Recurrent cholangiocarcinoma with long-term survival by multimodal treatment: A case report.

[This corrects the article DOI: 10.3892/mco.2021.2234.].

Histopathological atlas of desmoplastic reaction characterization in colorectal cancer.

Emergent scientific evidence indicates the central role of cancer-associated fibroblasts in determining whether the microenvironment of cancer works as friend or foe of the host; however, there is no unified histological evaluation framework of fibrotic stroma in colorectal cancers. Myxoid stroma and keloid-like collagen are site-specific histopathological features generated by cancer-associated fibroblasts, which appear exclusively in the tumor front during desmoplastic reaction. On the basis of these two stromal components, desmoplastic reaction is categorized into three patterns-immature, intermediate and mature-using hematoxylin and eosin staining. In January 2020, a prospective randomized clinical trial, JCOG1805, to elucidate the value of adjuvant chemotherapy in stage II colorectal cancer patients with pathological risk factors of recurrence was launched in Japan, in which intermediate/immature desmoplastic reaction is one of the four risk factors selected as inclusion criteria. This paper covers the diagnostic criteria for the desmoplastic reaction classification being used in the JCOG1805 study.

Automated Detection and Classification of Desmoplastic Reaction at the Colorectal Tumour Front Using Deep Learning.

The categorisation of desmoplastic reaction (DR) present at the colorectal cancer (CRC) invasive front into mature, intermediate or immature type has been previously shown to have high prognostic significance. However, the lack of an objective and reproducible assessment methodology for the assessment of DR has been a major hurdle to its clinical translation. In this study, a deep learning algorithm was trained to automatically classify immature DR on haematoxylin and eosin digitised slides of stage II and III CRC cases (n = 41). When assessing the classifier's performance on a test set of patient samples (n = 40), a Dice score of 0.87 for the segmentation of myxoid stroma was reported. The classifier was then applied to the full cohort of 528 stage II and III CRC cases, which was then divided into a training (n = 396) and a test set (n = 132). Automatically classed DR was shown to have superior prognostic significance over the manually classed DR in both the training and test cohorts. The findings demonstrated that deep learning algorithms could be applied to assist pathologists in the detection and classification of DR in CRC in an objective, standardised and reproducible manner.

Recurrent cholangiocarcinoma with long-term survival by multimodal treatment: A case report.

Long-term outcomes after surgical resection of bile duct cancer remain unsatisfactory, and survival, particularly after tumor recurrence, is poor. Gemcitabine and cisplatin combination (GC) therapy is the standard first-line treatment; however, second-line approaches are yet to be established. Radiotherapy may prolong the survival of patients with advanced biliary tract cancer, and particle radiotherapy delivers a more concentrated dose than conventional radiotherapy to deeper tumors. The present report describes the long-term survival of a 65-year-old man with distal bile duct cancer of pathological stage IIA (T2N0M0; depth of invasion, 5.5 mm) following multimodal treatment. Following subtotal stomach-preserving pancreatoduodenectomy, multiple hepatic recurrences were identified 9 months later, and GC therapy was initiated. The tumors were no longer evident 18 months later, and GC therapy was discontinued at the patient's request. A computed tomography (CT) scan performed 30 months after surgery identified a new solitary hepatic recurrence and duke pancreatic monoclonal antigen type-2 (DUPAN-2) levels were increased. Further GC therapy was declined. Carbon ion radiotherapy (CIRT) at a dose of 60 Gy [relative biological effectiveness (RBE)-weighted absorbed dose] was then delivered in four fractions over 4 days [15 Gy (RBE)/day]. Tumor size decreased on CT, and fluorodeoxyglucose-positron emission tomography/CT revealed a decline in the standardized uptake value of the tumor after 2 months, with decreased DUPAN-2 levels. Following regrowth of the hepatic recurrence, CIRT was repeated at a dose of 66 Gy (RBE) in four fractions over 4 days [16.5 Gy (RBE)/day] and stable disease was maintained for 19 months. After 19 months, CT revealed tumor regrowth and another new metastatic lesion was identified in the left kidney. The patient received systematic chemotherapy again and died of the disease 81 months after the initial surgery. In conclusion, CIRT is a potential treatment option to control solitary recurrence of biliary tract cancer.

Periostin as a key molecule defining desmoplastic environment in colorectal cancer.

Categorizing desmoplastic reaction (DR) based on the histological findings of cancer-associated fibroblasts is shown to be a promising novel method to predict prognosis of patients with colorectal cancer (CRC). Periostin (POSTN) in cancer-associated stroma is reportedly associated with poor clinical outcomes. Immunohistochemical staining with an anti-POSTN antibody was performed in 73 patients with pStage III CRC (cohort 1). In addition, to evaluate mRNA and protein expression levels of POSTN, we analyzed paired normal and invasive cancer frozen specimens by quantitative real-time polymerase chain reaction and western blot analysis in 41 patients (cohort 2). In cohort 1, according to the DR categorization, 18, 22, and 33 patients were classified as immature, intermediate, and mature, respectively. High immunoreactivity of POSTN was observed 100%, 68.2%, and 27.3%, respectively (p < 0.0001). The 5-year relapse-free survival rates were 56.8% and 82.7% in high and low POSTN expression subgroups, respectively (p = 0.015). In cohort 2, the POSTN mRNA and protein levels were significantly higher in the immature stroma as compared to the stroma characterized as other DR patterns. POSTN expression was closely associated with DR categorization. POSTN may be a key molecule that contributes to the malignant potential of CRC.

Primary Tumor Histology Affects Oncological Outcomes Independently of the Anatomical Extent of Disease in Colorectal Liver Metastasis.

INTRODUCTION: Growing evidence indicates the prognostic importance of the crosstalk between cancer cells and stroma through the induction of epithelial-mesenchymal transition (EMT). This study aimed to clarify the prognostic value of evaluating primary tumor histology with the anatomical extent of disease in patients with colorectal liver metastasis (CRLM). METHODS: Prognostic analyses were performed in 411 CRLM patients who underwent hepatectomy at two institutions. Tumors were graded into one of three histological categories based on integrated assessment of EMT-associated histology (HistologyEMT) in primary tumors, i.e., poorly differentiated clusters (PDCs) and desmoplastic reaction (DR). RESULTS: A prognostic grouping system for the anatomical extent of disease (N stage, liver metastasis number and size, and extrahepatic disease; Gradeanatomical) stratified patients into three groups with different five-year relapse-free survival (RFS) rates after hepatectomy: A, 31% (191 patients); B, 15% (124 patients); and C, 6% (96 patients; P < 0.0001). HistologyEMT (A, G1 PDC and mature-type DR; C, G3 PDC and immature-type DR; and B, others) identified 49, 120, and 242 patients with 46%, 5%, and 22% five-year RFS, respectively (P < 0.0001). Among prognostic factors, the Akaike information criterion was most favorable in Gradeanatomical, followed by HistologyEMT. Multivariate analysis demonstrated that these two factors independently impacted RFS; two-year RFS after hepatectomy in different patient groups had a wide range (10%-76%). CONCLUSIONS: Histological assessment of dedifferentiation and the stromal environment of primary tumors contributed to effective risk stratification of early relapse after hepatectomy, which could be useful to determine clinical management for CRLM patients.

Significance of mesothelin expression in preoperative endoscopic biopsy specimens for colorectal cancer prognosis.

Mesothelin (MSLN) is a cell surface glycoprotein that is normally expressed in the mesothelial cells but highly expressed in several malignant tumors, where the high expression is generally associated with poor prognosis. In this work, 512 patients with stage III colorectal cancer (CRC) were examined to ascertain the prognostic value of MSLN expression in preoperative endoscopic biopsy specimens. MSLN expression was evaluated by immunohistochemical staining. The tumor cells were MSLN-positive in 61 of the 512 patients (11.9%). MSLN expression was associated with a shorter disease-specific survival (DSS) period (5-year DSS = 68.7%, P = 0.0008). Besides, by multivariate analysis, MSLN expression was identified to be a marker of poor prognosis by multivariate analysis (P = 0.0033, hazard ratio (HR) = 2.31) as well as macroscopic type (P = 0.047, HR = 1.82) among the factors that can be evaluated preoperatively. MSLN-positive patients had a significantly poorer prognosis regardless of adjuvant chemotherapy administration (P = 0.0081 and P = 0.0018 for surgery alone and chemotherapy, respectively). MSLN-positive patients in the adjuvant chemotherapy group exhibited a significantly lower risk of recurrence when compared with those in the surgery alone group (P = 0.0090). In conclusion, high MSLN expression observed in preoperative endoscopic biopsy specimens of stage III CRC was an independent poor prognostic factor. Preoperative evaluation of MSLN by immunohistochemical staining might be applied to select individuals for intensive preoperative chemotherapy among the stage III CRC patients.