Differences in the Difficulty of Accessing Various 3-Dimensional Locations Under Mirror-Image Conditions During Laparoscopic Surgery.

BACKGROUND: Laparoscopic colon surgery frequently requires performing maneuvers under mirror-images conditions; the complexity differs depending on the surgical site location in the abdominal cavity. However, no previous reports have examined this. METHODS: Eleven surgeons participated in this study. Operations were performed on 25 points placed at the bottom and sides of a laparoscopic training box under mirror-image conditions. The mean time-point required to operate at each point and variation between surgeons were evaluated. RESULTS: When the right hand was used, time-points to touch the right side-superficial ends were 0.50 to 0.58 and 0.27 to 0.45 for the other sites. With the left hand, time-points to touch the left side-superficial ends were 0.58 to 0.63 and 0.28 to 0.51 for the other sites, indicating that the most difficult manipulation was at the proximal site of the surgical port. The variation in the difficulty according to the spots increased with a decrease in the surgeon's experience (right hand, r=-0.248; left hand, r=-0.491). CONCLUSIONS: In performing laparoscopic surgery under mirror-image conditions, the technical difficulty varies by location, and operating in locations close to the forceps port is the most difficult.

Ceramide synthase CERS4 gene downregulation is associated with KRAS mutation in colorectal cancer.

Ceramide, the central molecule in sphingolipid synthesis, is a bioactive lipid that serves as a regulatory molecule in the anti-inflammatory responses, apoptosis, programmed necrosis, autophagy, and cell motility of cancer cells. In particular, the authors have reported differences in sphingolipid content in colorectal cancer tissues. The associations among genetic mutations, clinicopathological factors, and sphingolipid metabolism in colorectal cancer (CRC) have not been investigated. The objective of this study is to investigate the association between genes associated with sphingolipid metabolism, genetic variations in colorectal cancer (CRC), and clinicopathological factors in CRC patients. We enrolled 82 consecutive patients with stage I-IV CRC who underwent tumor resection at a single institution in 2019-2021. We measured the expression levels of genes related to sphingolipid metabolism and examined the relationships between CRC gene mutations and the clinicopathological data of each individual patient. The relationship between CRC gene mutations and expression levels of ceramide synthase (CERS), N-acylsphingosine amidohydrolase (ASAH), and alkaline ceramidase (ACER) genes involved in sphingolipid metabolism was examined CRES4 expression was significantly lower in the CRC KRAS gene mutation group (p = 0.004); vascular invasion was more common in colorectal cancer patients with high CERS4 expression (p = 0.0057). By examining the correlation between sphingolipid gene expression and clinical factors, we were able to identify cancer types in which sphingolipid metabolism is particularly relevant. CERS4 expression was significantly reduced in KRAS mutant CRC. Moreover, CRC with decreased CERS4 showed significantly more frequent venous invasion.

Clinicopathological Characteristics of Anastomotic Recurrence After Curative Resection for Colorectal Cancer: Comparison With Nonanastomotic Local Recurrences.

BACKGROUND: Anastomotic recurrence is thought to be caused by implantation of tumor cells to the anastomotic line; however, its risk factors and prognostic significance remain unclear. OBJECTIVE: This study aimed to clarify the risk factors for anastomotic recurrence in colorectal cancer and assess the prognosis in comparison to nonanastomotic local recurrence. DESIGN: A single-center retrospective observational study. SETTINGS: The medical records of the study participants were retrospectively collected from the Department of Surgical Oncology at the University of Tokyo Hospital database. PATIENTS: This study included 1584 patients with colorectal cancer who underwent surgical resection between January 2005 and December 2017. We focused on 15 patients who had an anastomotic recurrence. MAIN OUTCOME MEASURES: The main outcome measures were the risk factors of anastomotic recurrence at the primary resection and prognosis data in comparison to that of nonanastomotic local recurrence. RESULTS: There were 15 patients (0.95%) with anastomotic recurrence and 35 (2.21%) with nonanastomotic local recurrence. Univariate analysis revealed that lymph node metastasis and advanced T stage are the risk factors for anastomotic recurrence. The prognosis of patients with anastomotic recurrence was similar to that of those with nonanastomotic local recurrence who underwent resection. LIMITATIONS: The small number of patients with anastomotic recurrence is a major limitation of this study. Additionally, the retrospective study design may have increased the risk of selection bias. CONCLUSIONS: Lymph node metastasis and advanced T stage were associated with anastomotic recurrence. The prognosis of patients with anastomotic recurrence was similar to that with resected nonanastomotic local recurrence. Thus, surveillance should be carefully continued while considering the poor prognosis of patients with anastomotic recurrence. See Video Abstract at http://links.lww.com/DCR/C92 . CARACTERSTICAS CLINICOPATOLGICAS DE LA RECURRENCIA ANASTOMTICA DESPUS DE LA RESECCIN CURATIVA DEL CNCER COLORRECTAL COMPARACIN CON LAS RECURRENCIAS LOCALES NO ANASTOMTICAS: ANTECEDENTES:Se cree que la recurrencia anastomótica es causada por la implantación de células tumorales en la línea anastomótica; sin embargo, los factores de riesgo asociados y el significado en cuanto a pronóstico siguen sin estar claros.OBJETIVO:Este estudio tuvo como objetivo aclarar los factores de riesgo para la recurrencia anastomótica en el cáncer colorrectal y evaluar el pronóstico en comparación con la recurrencia local no anastomótica.DISEÑO:Un estudio observacional retrospectivo de un solo centro.ESCENARIO:Los registros médicos de los participantes del estudio se recopilaron retrospectivamente de la base de datos del Departamento de Cirugía Oncológica del Hospital de la Universidad de Tokio.PACIENTES:Este estudio incluyó a 1584 pacientes con cáncer colorrectal que se sometieron a resección quirúrgica entre enero de 2005 y diciembre de 2017. Nos enfocamos en 15 pacientes que tuvieron recurrencia anastomótica.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron los factores de riesgo de recurrencia anastomótica en la resección primaria y los datos de pronóstico en comparación con la recurrencia local no anastomótica.RESULTADOS:Hubo 15 pacientes (0.95%) con recurrencia anastomótica y 35 (2.21%) con recurrencia local no anastomótica. El análisis univariable reveló que la metástasis en los ganglios linfáticos y el estadio T avanzado son los factores de riesgo para la recurrencia anastomótica. El pronóstico de los pacientes con recidiva anastomótica fue similar al de aquellos con recidiva local no anastomótica sometidos a resección.LIMITACIONES:El pequeño número de pacientes con recurrencia anastomótica es una limitación importante de este estudio. Además, el diseño retrospectivo del estudio puede haber aumentado el riesgo de sesgo de selección.CONCLUSIONES:La metástasis en los ganglios linfáticos y el estadio T avanzado se asociaron con recurrencia anastomótica. El pronóstico de los pacientes con recidiva anastomótica fue similar al de la recidiva local no anastomótica resecada. Por lo tanto, la vigilancia debe continuarse cuidadosamente considerando el mal pronóstico de los pacientes con recurrencia anastomótica. Consulte Video Resumen en http://links.lww.com/DCR/C92 . (Traducción-Dr. Jorge Silva Velazco ).

Performance of an artificial intelligence-based diagnostic support tool for early gastric cancers: Retrospective study.

OBJECTIVES: Endoscopists' abilities to diagnose early gastric cancers (EGCs) vary, especially between specialists and nonspecialists. We developed an artificial intelligence (AI)-based diagnostic support tool "Tango" to differentiate EGCs and compared its performance with that of endoscopists. METHODS: The diagnostic performances of Tango and endoscopists (34 specialists, 42 nonspecialists) were compared using still images of 150 neoplastic and 165 non-neoplastic lesions. Neoplastic lesions included EGCs and adenomas. The primary outcome was to show the noninferiority of Tango (based on sensitivity) over specialists. The secondary outcomes were the noninferiority of Tango (based on accuracy) over specialists and the superiority of Tango (based on sensitivity and accuracy) over nonspecialists. The lower limit of the 95% confidence interval (CI) of the difference between Tango and the specialists for sensitivity was calculated, with >-10% defined as noninferiority and >0% defined as superiority in the primary outcome. The comparable differences between Tango and the endoscopists for each performance were calculated, with >10% defined as superiority and >0% defined as noninferiority in the secondary outcomes. RESULTS: Tango achieved superiority over the specialists based on sensitivity (84.7% vs. 65.8%, difference 18.9%, 95% CI 12.3-25.3%) and demonstrated noninferiority based on accuracy (70.8% vs. 67.4%). Tango achieved superiority over the nonspecialists based on sensitivity (84.7% vs. 51.0%) and accuracy (70.8% vs. 58.4%). CONCLUSIONS: The AI-based diagnostic support tool for EGCs demonstrated a robust performance and may be useful to reduce misdiagnosis.

Surgical outcomes of robotic, laparoscopic, and open low anterior resection after preoperative chemoradiotherapy for patients with advanced lower rectal cancer.

PURPOSE: We investigated the surgical outcomes of robotic low anterior resection (LAR) for lower rectal cancer after preoperative chemoradiotherapy (pCRT). METHODS: A total of 175 patients with lower rectal cancer who underwent LAR after pCRT between 2005 and 2020 were stratified into open (OS, n = 65), laparoscopic (LS, n = 64), and robotic surgery (RS, n = 46) groups. We compared the clinical, surgical, and pathological results among the three groups. RESULTS: The RS and LS groups had less blood loss than the OS group (p < 0.0001). The operating time in the RS group was longer than in the LS and OS groups (p < 0.0001). The RS group had a significantly longer mean distal margin than the LS and OS groups (25.4 mm vs. 20.7 mm and 20.3 mm, respectively; p = 0.026). There was no significant difference in the postoperative complication rate among the groups. The local recurrence rate in the RS group was comparable to those in the LS and OS groups. CONCLUSION: Robotic LAR after pCRT was performed safely for patients with advanced lower rectal cancer. It provided a longer distal margin and equivalent local control rates.

Current Status of Artificial Intelligence-Based Computer-Assisted Diagnosis Systems for Gastric Cancer in Endoscopy.

Artificial intelligence (AI) is gradually being utilized in various fields as its performance has been improving with the development of deep learning methods, availability of big data, and the progression of computer processing units. In the field of medicine, AI is mainly implemented in image recognition, such as in radiographic and pathologic diagnoses. In the realm of gastrointestinal endoscopy, although AI-based computer-assisted detection/diagnosis (CAD) systems have been applied in some areas, such as colorectal polyp detection and diagnosis, so far, their implementation in real-world clinical settings is limited. The accurate detection or diagnosis of gastric cancer (GC) is one of the challenges in which performance varies greatly depending on the endoscopist's skill. The diagnosis of early GC is especially challenging, partly because early GC mimics atrophic gastritis in the background mucosa. Therefore, several CAD systems for GC are being actively developed. The development of a CAD system for GC is considered challenging because it requires a large number of GC images. In particular, early stage GC images are rarely available, partly because it is difficult to diagnose gastric cancer during the early stages. Additionally, the training image data should be of a sufficiently high quality to conduct proper CAD training. Recently, several AI systems for GC that exhibit a robust performance, owing to being trained on a large number of high-quality images, have been reported. This review outlines the current status and prospects of AI use in esophagogastroduodenoscopy (EGDS), focusing on the diagnosis of GC.

Giant filiform polyposis with high-grade dysplasia: A case report and review of the literature.

Introduction and importance: Filiform polyposis, a rare condition also referred to as inflammatory polyposis or pseudopolyposis, is commonly observed in cases of inflammatory bowel disease, such as ulcerative colitis or Crohn's disease. It is generally considered a benign tumour characterised by multiple finger-like projections that are mostly observed in the transverse and descending colon. Case presentation: A 69-year-old woman with a history of ulcerative colitis for 18 years who underwent temporary decompression ileostomy for large bowel obstruction at another hospital was referred to our institution for further investigation. Abdominal computed tomography revealed bowel wall thickening of the transverse colon, and colonoscopy revealed stenosis in the hepatic flexure obstructing the endoscope. Although several biopsies of the tumour showed no malignancy, laparoscopic subtotal colectomy with lymph node dissection was performed. Histopathological findings revealed localised filiform polyposis with dysplasia. Clinical discussion: Filiform polyposis has been considered a benign inflammatory polyp without any risk of dysplasia. We accumulated previous cases of giant filiform polyposis and reviewed their characteristics. The presented case of filiform polyposis with ulcerative colitis complicated with high-grade dysplasia highlights the importance of considering malignancy in patients with filiform polyposis. Conclusion: In cases of giant filiform polyposis, even when no malignancy is detected, surgical resection should be considered for the possibility of a malignant component of dysplasia.

Spinal epidural arteriovenous fistula in 3 cats.

Three young adult cats with intermittent spinal hyperesthesia and paraparesis and diagnosed with spinal epidural arteriovenous fistula are described. In all 3 cases, magnetic resonance imaging (MRI) showed focal dilatation of the veins in the epidural space of the thoracic spinal cord, whereas computed tomography angiography (CTA) showed dilatation and enhancement from the intercostal vein to the azygos vein at the same site in the arterial phase. Dorsal laminectomy and occlusion of the interarcuate branches running across the dorsal aspect of the spinal cord were performed in all 3 cats to decompress the spinal cord, which resulted in a remission of clinical signs and no recurrence during 14 to 40 months of follow-up after surgery in all cases.

Clinical impact of primary tumor sidedness and sex on unresectable post-recurrence survival in resected pathological stage II-III colorectal cancers: a nationwide multicenter retrospective study.

BACKGROUND: Several studies have demonstrated that right-sided tumors have poorer prognosis than left-sided tumors in patients with unresectable colorectal cancer (CRC). The predictive ability of the tumor sidedness in CRC treated with chemotherapy in each sex is unclear. METHODS: Subjects were 964 unresectable recurrent patients treated with chemotherapy with stage II-III CRC after curative resection between 2004 and 2012. Post-recurrence cancer-specific survival (CSS) for each sex was examined. RESULTS: Patients were 603 males (222 right-side tumors (cecum to transverse colon) and 381 left-sided tumors (descending colon to rectum)), and 361 females (167 right-side tumors and 194 left-sided tumors). Right-sided tumors developed peritoneal recurrences in males and females. Left-sided tumors were associated with locoregional recurrences in males and with lung recurrences in females. Right-sided tumors were associated with shorter post-recurrence CSS in both sexes. In males, multivariate analyses showed that right-sided tumors were associated with shorter post-recurrence CSS (HR: 1.53, P < 0.0001) together with the presence of regional lymph node metastasis histopathological type of other than differentiated adenocarcinoma, the recurrence of liver only, the recurrence of peritoneal dissemination only, and relapse-free interval less than one-year. In females, multivariate analyses showed that right-sided tumors were associated with shorter post-recurrence CSS (HR: 1.50, P = 0.0019) together with advanced depth of invasion, the presence of regional lymph node metastasis, and recurrence of liver only. CONCLUSIONS: Primary tumor sidedness in both sexes in unresectable recurrent CRC patients treated with chemotherapy may have prognostic implications for post-recurrence CSS.

Preoperative diagnosis of obstructive colitis in colorectal cancer patients who underwent self-expandable metallic stent insertion as a bridge to surgery.

PURPOSE: Obstructive colitis (OC) is a risk factor of anastomotic leakage in colorectal cancer resection. We aimed to clarify the relationship between the severity of OC and clinicopathological findings and to detect predictive factors of OC. METHODS: We retrospectively reviewed 43 cases of colectomy after self-expandable metallic stent placement for left-sided colorectal cancer. Preoperative diagnosis of OC was made by multiple modalities (initial computed tomography (CT), presurgical CT, and colonoscopy). We classified OC macroscopically in resected specimens into five groups (Grade 0: none, 1: mild [mild edema], 2: moderate [severe edema, redness, erosion], 3: severe [ulceration, bleeding], 4: very severe [necrosis, perforation]), and investigated the relationship between the preoperative assessment, surgical findings and the severity of OC. RESULTS: OC of Grade 2 or more (53.5%) was significantly correlated with severe edema in initial CT. There was no significant correlation between OC and anastomosis rate. The creation of covering stoma was significantly higher in the Grade 2 or more OC group. No leakage was observed in either group. CONCLUSIONS: Initial CT may be most useful for prediction of OC. It is important to make a preoperative diagnosis of OC by combining multiple modalities, which enables to determine the appropriate location for resection, anastomosis, and construction of a covering stoma.

The preoperative geriatric nutritional risk index (GNRI) is an independent prognostic factor in elderly patients underwent curative resection for colorectal cancer.

The world is becoming longer-lived, and the number of elderly colorectal cancer patients is increasing. It is very important to identify simple and inexpensive postoperative predictors in elderly colorectal cancer patients. The geriatric nutritional risk index (GNRI) is a marker of systemic nutrition and is associated with poor survival in various kinds of cancers. A few reports have investigated recurrence factors using preoperative GNRI with CRC (colorectal cancer) patients. This study aimed to investigate whether preoperative GNRI is associated with recurrence-free survival (RFS) and overall survival (OS) in elderly patients with CRC. This study retrospectively enrolled 259 patients with Stage I-III CRC who were more than 65 years old and underwent curative surgery at a single institution in 2012-2017. We classified them into low GNRI (RFS: ≤ 90.5, OS ≤ 101.1) group and high GNRI (RFS: > 90.5, OS > 101.1) group. Multivariable analyses showed low GNRI group was an independent risk factor for 3-year RFS (P = 0.006) and OS (P = 0.001) in the patients with CRC. Kaplan-Meier analysis showed 3-year RFS and 3-year OS were significantly worse in the low GNRI group than in high GNRI group (p = 0.001, 0.0037). A low-preoperative GNRI was significantly associated with a poor prognosis in elderly CRC patients.

Predicting Overall Survival Using Preoperative Nutritional and Inflammation Status for Colorectal Cancer.

AIM: It has been shown that nutritional status and inflammation correlate with survival in patients with various cancer types. In this study, we evaluated several kinds of nutritional and inflammation parameters in preoperative blood samples and constructed new risk model predicting survival in patients with colorectal cancer. PATIENTS AND METHODS: We retrospectively examined 286 patients with stage I-III colorectal cancer who had undergone curative resection at Teikyo University Hospital. The association between overall survival (OS) and nutritional status and inflammation factors were examined using Kaplan-Meier curves and log-rank tests. RESULTS: Serum albumin, cholesterol and C-reactive protein concentration, neutrophil count and platelet count were shown to be correlated with OS. We constructed a new risk model (nutrition inflammation status, NIS) using these factors, and compared it with other nutrition and inflammation models. CONCLUSION: NIS was useful as a new model for predicting OS in patients undergoing curative resection for colorectal cancer, compared with known models.

Poor nutrition and sarcopenia are related to systemic inflammatory response in patients with rectal cancer undergoing preoperative chemoradiotherapy.

BACKGROUND: Preoperative chemoradiotherapy (CRT) is the standard therapy for locally advanced rectal cancer (LARC). However, the changes that the patient's physical status during CRT, such as host systemic inflammatory response, nutritional status, and muscle depletion, are still unclear. We evaluated the clinical significance of malnutrition and sarcopenia for patients with LARC undergoing CRT. PATIENTS AND METHODS: Patients with LARC treated with CRT following radical surgery at our institution between 2006 and 2016 (N = 225) were retrospectively analyzed. A new prognostic score (PNSI) was devised based on the prognostic nutritional index (PNI) and the psoas muscle mass index (PMI): patients with malnutrition/sarcopenia were scored 2; patients with one and neither abnormality were scored 1 and 0, respectively. RESULTS: Neutrophil/lymphocyte ratio, monocyte/lymphocyte ratio, and platelet/lymphocyte ratio increased, whereas PNI and PMI decreased after CRT. There were 130, 73, and 22 patients in the PNSI 0, 1, and 2 groups, respectively. Patients with higher PNSI had higher residual tumor size (p = 0.003), yT stage (p = 0.007), ypStage (p < 0.001), post-CRT platelet/lymphocyte ratio (p = 0.027), and post-CRT C-reactive protein/albumin ratio (p < 0.001). Post-CRT PNSI was associated with overall survival and was an independent poor prognosis factor (PNSI 1 to 0, hazard ratio 2.40, p = 0.034, PNSI 2 to 0, hazard ratio 2.66, p = 0.043) together with mesenteric lymph node metastasis, lateral lymph node metastasis, and histology. CONCLUSION: A combined score of post-CRT malnutrition/sarcopenia is promising for predicting overall survival in LARC.

Prognoses in Pathologically Confirmed T1 Lower Rectal Cancer Patients with or without Preoperative Therapy: An Analysis Using the Surveillance, Epidemiology, and End Results Database.

INTRODUCTION: Preoperative chemoradiotherapy (CRT) is the standard therapy for downstaging in locally advanced lower rectal cancer. However, it remains unclear whether rectal cancers downstaged by preoperative therapy show similar prognoses to those of the same stage without preoperative therapy. We previously demonstrated that preoperative CRT did not affect prognosis of rectal cancer with pathological T1N0 (pT1N0) stage in a single institute. Here, using a larger dataset, we compared prognoses of (y)pT1 rectal cancer stratified by the use of preoperative therapy and analyzed prognostic factors. METHODS: Cases of pT1N0 rectal cancer, registered between 2004 and 2016, were extracted from the Surveillance, Epidemiology, and End Results database. Patients were categorized as the "ypT1 group" if they had undergone preoperative therapy before surgery or as the "pT1 group" if they had undergone surgery alone. Overall survival (OS) and cancer-specific survival (CSS) between these groups of patients were compared. Factors associated with CSS and OS were identified by univariate and multivariate analyses. RESULTS: Among 3,757 eligible patients, ypT1 and pT1 groups comprised 720 and 3,037 patients, respectively. While ypT1 patients showed poorer CSS than ypT1 patients, there was no significant difference in OS. Preoperative therapy was not an independent prognostic factor for CSS or OS. Multivariate analysis identified age and histological type as significant factors associated with CSS. Sex, age, race, and number of lymph nodes dissected were identified as significant factors associated with OS. CONCLUSIONS: Prognosis among patients with (y)p T1N0 rectal cancer was similar irrespective of whether they underwent preoperative therapy, which is consistent with our previous observations.

Women are predisposed to early dose-limiting toxicities during adjuvant CAPOX for colorectal cancer.

AIM: Oxaliplatin-based adjuvant chemotherapy was demonstrated to be beneficial for stage III or high-risk stage II colorectal cancer (CRC). Moreover, a recent international collaborative trial suggested 3-months CAPOX as an alternative regimen for low-risk stage III colorectal cancer (CRC) patients. Thus, it is important to clarify the frequency and predictive markers of dose-limiting toxicities (DLTs) developed within the short-course CAPOX cycles. METHODS: We investigated CRC patients who underwent radical surgery and adjuvant CAPOX therapy at our hospital between December 2010 and February 2021. Patients who received initially reduced doses of CAPOX and those who had early recurrence were excluded. We reviewed the age, sex, comorbidities, physical, laboratory and oncological data and other perioperative factors. The associations between these variables and early DLTs within four cycles of CAPOX were examined by multivariate analyses using logistic regression models. RESULTS: Among 168 patients (96 men, mean age: 58.3 years), 120 (71%) developed early DLTs. Patients with early DLTs were predominantly women and sarcopenic and habitual alcohol consumers. On multivariate analyses, only the female sex was an independent predictive factor for early DLTs (odds ratio: 2.61, P = .027). CONCLUSION: Women were prone to early DLTs during adjuvant CAPOX in the current study. Doctors should be aware of the sex difference in the incidence of early DLTs, adjust the CAPOX dosage and provide supportive care for female CRC patients.

Automatic anatomical classification of colonoscopic images using deep convolutional neural networks.

BACKGROUND: A colonoscopy can detect colorectal diseases, including cancers, polyps, and inflammatory bowel diseases. A computer-aided diagnosis (CAD) system using deep convolutional neural networks (CNNs) that can recognize anatomical locations during a colonoscopy could efficiently assist practitioners. We aimed to construct a CAD system using a CNN to distinguish colorectal images from parts of the cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum. METHOD: We constructed a CNN by training of 9,995 colonoscopy images and tested its performance by 5,121 independent colonoscopy images that were categorized according to seven anatomical locations: the terminal ileum, the cecum, ascending colon to transverse colon, descending colon to sigmoid colon, the rectum, the anus, and indistinguishable parts. We examined images taken during total colonoscopy performed between January 2017 and November 2017 at a single center. We evaluated the concordance between the diagnosis by endoscopists and those by the CNN. The main outcomes of the study were the sensitivity and specificity of the CNN for the anatomical categorization of colonoscopy images. RESULTS: The constructed CNN recognized anatomical locations of colonoscopy images with the following areas under the curves: 0.979 for the terminal ileum; 0.940 for the cecum; 0.875 for ascending colon to transverse colon; 0.846 for descending colon to sigmoid colon; 0.835 for the rectum; and 0.992 for the anus. During the test process, the CNN system correctly recognized 66.6% of images. CONCLUSION: We constructed the new CNN system with clinically relevant performance for recognizing anatomical locations of colonoscopy images, which is the first step in constructing a CAD system that will support us during colonoscopy and provide an assurance of the quality of the colonoscopy procedure.

The robust performance of carcinoembryonic antigen levels after adjuvant chemotherapy for the recurrence risk stratification in patients with colorectal cancer.

BACKGROUND AND OBJECTIVES: Most guidelines of colorectal cancers (CRCs) recommend evaluating the serum carcinoembryonic antigen (CEA) level during postoperative surveillance to detect tumor recurrence, which originates from postsurgery residual tumor cells. We hypothesized that the postadjuvant chemotherapy CEA level may be the most accurate biomarker to predict tumor recurrence, and we evaluated the prognostic significance of the postadjuvant chemotherapy CEA level in patients with stage II and III CRCs. PATIENTS AND METHODS: We retrospectively analyzed the cases of 150 Stage II-III CRC patients who had undergone curative surgery and adjuvant chemotherapy. Preoperative, postoperative, and postadjuvant chemotherapy CEA levels were evaluated, and their associations with recurrence-free survival (RFS) were assessed. RESULTS: The Kaplan-Meier curves showed that a high preoperative CEA level, high postoperative CEA, and high postadjuvant chemotherapy CEA were associated with poor RFS (p = .001, .0001, and .001, respectively). The multivariate analysis demonstrated that high postadjuvant chemotherapy CEA was an independent factor for poor RFS (HR 2.55, 95% confidence interval: 1.08-6.05, p = .033), whereas high preoperative and postoperative CEA levels were not. CONCLUSIONS: The serum levels of postadjuvant chemotherapy CEA were a strong prognostic biomarker in patients with Stage II-III CRCs who had undergone surgery followed by adjuvant chemotherapy.

Very long-chain fatty acids are accumulated in triacylglycerol and nonesterified forms in colorectal cancer tissues.

Colorectal cancer (CRC) is a major cancer, and its precise diagnosis is especially important for the development of effective therapeutics. In a series of metabolome analyses, the levels of very long chain fatty acids (VLCFA) were shown to be elevated in CRC tissues, although the endogenous form of VLCFA has not been fully elucidated. In this study we analyzed the amount of nonesterified fatty acids, acyl-CoA species, phospholipids and neutral lipids such as cholesterylesters using liquid-chromatography-mass spectrometry. Here we showed that VLCFA were accumulated in triacylglycerol (TAG) and nonesterified forms in CRC tissues. The levels of TAG species harboring a VLCFA moiety (VLCFA-TAG) were significantly correlated with that of nonesterified VLCFA. We also showed that the expression level of elongation of very long-chain fatty acids protein 1 (ELOVL1) is increased in CRC tissues, and the inhibition of ELOVL1 decreased the levels of VLCFA-TAG and nonesterified VLCFA in CRC cell lines. Our results suggest that the upregulation of ELOVL1 contributes to the accumulation of VLCFA-TAG and nonesterified VLCFA in CRC tissues.

Impact of Colon Cancer Location on the Prognostic Significance of Nutritional Indexes and Inflammatory Markers.

BACKGROUND/AIM: The prognosis of colorectal cancer is reported to differ depending on the tumor site, and clinical differences depending on the site of occurrence have gained attention. The aim was to compare nutrition index and inflammatory markers according to the site of colon cancer. PATIENTS AND METHODS: We retrospectively analyzed 272 cases of stage I-III colon cancer (55% males, 45% females). The clinical characteristics, nutrition index and inflammatory markers were compared between patients with right colon cancer (RCC, n=119) and those with left colon cancer (LCC, n=153), and the relapse-free survival was then compared. RESULTS: RCC was associated with older age (p=0.03), female gender (p=0.003), higher T stage (p=0.01), elevated platelet/lymphocyte ratio (PLR) (p=0.009), and elevated CONUT score (p=0.028). The prognostic values differed between RCC and LCC (RCC: CONUT score, p=0.04, LCC: PLR, p=0.02). CONCLUSION: RCC was associated with an elevated CONUT score and PLR. In RCC, the CONUT score was an independent recurrence factor, and in LCC, the PLR was an independent recurrence factor.

Impact of Fluoropyrimidine and Oxaliplatin-based Chemoradiotherapy in Patients With Locally Advanced Rectal Cancer.

BACKGROUND/AIM: To evaluate the benefits of the addition of oxaliplatin (OX) to fluoropyrimidine (FP)-based neoadjuvant chemoradiotherapy (CRT) for patients with locally advanced rectal cancers (LARCs). PATIENTS AND METHODS: We performed retrospective analyses comparing the pathological complete response (pCR) rate, overall survival (OS), recurrence-free survival (RFS), and local recurrence-free survival (LRFS) between FP-based and FP+OX-based CRT groups and for patients who had completed the CRT. RESULTS: One hundred patients were included in the analyses: the pCR rate, OS, RFS, and LRFS were similar between these groups. The FP+OX group showed significantly more frequent incompleteness of the CRT compared to the FP group (p=0.049). Among the patients who had completed the CRT, the FP+OX group demonstrated significantly improved LRFS compared to the FP group (p=0.048). CONCLUSION: The addition of OX to an FP regimen in neoadjuvant CRT for LARC may reduce local recurrence in patients who have achieved good compliance to CRT.