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Purpose@#This study aimed to evaluate the predictive value of lymph node yield (LNY) for survival outcomes according to tumor response after preoperative chemoradiotherapy (PCRT) in patients with rectal cancer. @*Methods@#This study was a retrospective study conducted in a tertiary center. A total of 1,240 patients with clinical stage II or III rectal cancer who underwent curative resection after PCRT between 2007 and 2016 were included. Patients were categorized into the good response group (tumor regression grade [TRG], 0–1) or poor response group (TRG, 2–3). Propensity score matching was performed for age, sex, and pathologic stage between LNY of ≥12 and LNY of <12 within tumor response group. The primary outcome was 5-year disease-free survival (DFS) and overall survival (OS). @*Results@#LNY and positive lymph nodes were inversely correlated with TRG. In good responders, 5-year DFS and 5-year OS of patients with LNY of <12 were better than those with LNY of ≥12, but there was no statistical significance. In poor responders, the LNY of <12 group had worse survival outcomes than the LNY of ≥12 group, but there was also no statistical significance. LNY of ≥12 was not associated with DFS and OS in multivariate analysis. @*Conclusion@#LNY of <12 showed contrasting outcomes between the good and poor responders in 5-year DFS and OS. LNY of 12 may not imply adequate oncologic surgery or proper staging in rectal cancer patients treated by PCRT. Furthermore, a decrease in LNY should be comprehended differently according to tumor response.
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Purpose@#This study was designed to determine the feasibility of preoperative chemoradiotherapy (PCRT) in patients with clinical T2N0 distal rectal cancer. @*Methods@#Patients who underwent surgery for clinical T2N0 distal rectal cancer between January 2008 and December 2016 were included. Patients were divided into PCRT and non-PCRT groups. Non-PCRT patients underwent radical resection or local excision (LE) according to the surgeon’s decision, and PCRT patients underwent surgery according to the response to PCRT. Patients received 50.0 to 50.4 gray of preoperative radiotherapy with concurrent chemotherapy. @*Results@#Of 127 patients enrolled, 46 underwent PCRT and 81 did not. The mean distance of lesions from the anal verge was lower in the PCRT group (P=0.004). The most frequent operation was transanal excision and ultralow anterior resection in the PCRT and non-PCRT groups, respectively. Of the 46 patients who underwent PCRT, 21 (45.7%) achieved pathologic complete response, including 15 of the 24 (62.5%) who underwent LE. Rectal sparing rate was significantly higher in the PCRT group (11.1% vs. 52.2%, P<0.001). There were no significant differences in 3- and 5-year overall survival and recurrence-free survival regardless of PCRT or surgical procedures. @*Conclusion@#PCRT in clinical T2N0 distal rectal cancer patients increased the rectal sparing rate via LE and showed acceptable oncologic outcomes. PCRT may be a feasible therapeutic option to avoid abdominoperineal resection in clinical T2N0 distal rectal cancer.
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Purpose@#During diverting ileostomy reversal for rectal cancer patients who underwent previous sphincter-saving surgery, the extent of adhesion formation around the ileostomy site affects operative and postoperative outcomes. Anchoring sutures placed at the time of the ileostomy procedure may reduce adhesions around the ileostomy. This study aimed to evaluate the effects of anchoring sutures on the degree of adhesion formation and the postoperative course at the time of ileostomy reversal. @*Methods@#Patients who underwent sphincter-saving surgery with diverting ileostomy for rectal cancer between January 2013 and December 2017 were enrolled. Variables including the peritoneal adhesion index (PAI) score, operation time, the length of resected small bowel, operative complications, and postoperative hospital stay were collected prospectively and compared between the anchoring group (AG) and non-anchoring group (NAG). @*Results@#A total of 90 patients were included in this study, with 60 and 30 patients in the AG and NAG, respectively. The AG had shorter mean operation time (46.88 ± 16.37 minutes vs. 61.53 ± 19.36 minutes, P = 0.001) and lower mean PAI score (3.02 ± 2.53 vs. 5.80 ± 2.60, P = 0.001), compared with the NAG. There was no significant difference in the incidence of postoperative complications between the AG and NAG (5.0% vs. 13.3%, respectively; P = 0.240). @*Conclusion@#Anchoring sutures at the formation of a diverting ileostomy could decrease the adhesion score and operation time at ileostomy reversal, thus may be effective in improving perioperative outcomes.
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The genomic causes and clinical manifestations of hereditary colorectal cancer (HCRC) might be stratified into 2 groups, namely, familial (FCRC) and a limited sense of HCRC, respectively. Otherwise, FCRC is canonically classified into 2 major categories; Lynch syndrome (LS) or associated spectra and inherited polyposis syndrome. By contrast, despite an increasing body of genotypic and phenotypic traits, some FCRC cannot be clearly differentiated as definitively single type, and the situation has become more complex as additional causative genes have been discovered. This review provides an overview of HCRC, including 6 LS or associated spectra and 8 inherited polyposis syndromes, according to molecular pathogenesis. Variants and newly-identified FCRC are particularly emphasized, including MUTYH (or MYH)-associated polyposis, Muir-Torre syndrome, constitutional mismatch repair deficiency, EPCAM-associated LS, polymerase proofreading-associated polyposis, RNF43- or NTHL1-associated serrated polyposis syndrome, PTEN hamartoma tumor syndrome, and hereditary mixed polyposis syndrome. We also comment on the clinical utility of multigene panel tests, focusing on comprehensive cancer panels that include HCRC. Finally, HCRC surveillance strategies are recommended, based on revised or notable concepts underpinned by competent validation and clinical implications, and favoring major guidelines. As hereditary syndromes are mainly attributable to genomic constitutions of distinctive ancestral groups, an integrative national HCRC registry and guideline is an urgent priority.
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Purpose@#Carcinoma arising from Crohn disease (CD) is rare, and there is no clear guidance on how to properly screen for at-risk patients and choose appropriate care. This study aimed to evaluate the clinicopathological characteristics, treatment, and oncologic outcomes of CD patients diagnosed with colorectal cancer (CRC). @*Methods@#Using medical records, we retrospectively enrolled a single-center cohort of 823 patients who underwent abdominal surgery for CD between January 2006 and December 2015. CD-associated CRC patients included those with adenocarcinoma, lymphoma, or neuroendocrine tumors of the colon and rectum. @*Results@#Nineteen patients (2.3%) underwent abdominal surgery to treat CD-associated CRC. The mean duration of CD in the CD-associated CRC group was significantly longer than that in the benign CD group (124.7 ± 77.7 months vs. 68.9 ± 60.2 months, P = 0.006). The CD-associated CRC group included a higher proportion of patients with a history of perianal disease (73.7% vs. 50.2%, P = 0.035) and colonic location (47.4% vs. 6.5%, P = 0.001). Among 19 CD-associated CRC patients, 17 (89.5%) were diagnosed with adenocarcinoma, and of the 17 cases, 15 (88.2%) were rectal adenocarcinoma. On multivariable analyses for developing CRC, only colonic location was a risk factor (relative risk, 7.735; 95% confidence interval, 2.862–20.903; P = 0.001). @*Conclusion@#Colorectal malignancy is rare among CD patients, even among patients who undergo abdominal surgery. Rectal adenocarcinoma accounted for most of the CRC, and colonic location was a risk factor for developing CRC.
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Objective@#Adequate methods of combining T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) to assess complete response (CR) to chemoradiotherapy (CRT) for rectal cancer are obscure. We aimed to determine an algorithm for combining T2WI and DWI to optimally suggest CR on MRI using visual assessment. @*Materials and Methods@#We included 376 patients (male:female, 256:120; mean age ± standard deviation, 59.7 ± 11.1 years) who had undergone long-course CRT for rectal cancer and both pre- and post-CRT high-resolution rectal MRI during 2017– 2018. Two experienced radiologists independently evaluated whether a tumor signal was absent, representing CR, on both post-CRT T2WI and DWI, and whether the pre-treatment DWI showed homogeneous hyperintensity throughout the lesion. Algorithms for combining T2WI and DWI were as follows: ‘AND,’ if both showed CR; ‘OR,’ if any one showed CR; and ‘conditional OR,’ if T2WI showed CR or DWI showed CR after the pre-treatment DWI showed homogeneous hyperintensity. Their efficacies for diagnosing pathologic CR (pCR) were determined in comparison with T2WI alone. @*Results@#Sixty-nine patients (18.4%) had pCR. AND had a lower sensitivity without statistical significance (vs. 62.3% [43/69]; 59.4% [41/69], p = 0.500) and a significantly higher specificity (vs. 87.0% [267/307]; 90.2% [277/307], p = 0.002) than those of T2WI. Both OR and conditional OR combinations resulted in a large increase in sensitivity (vs. 62.3% [43/69]; 81.2% [56/69], p < 0.001; and 73.9% [51/69], p = 0.008, respectively) and a large decrease in specificity (vs. 87.0% [267/307]; 57.0% [175/307], p < 0.001; and 69.1% [212/307], p < 0.001, respectively) as compared with T2WI, ultimately creating additional false interpretations of CR more frequently than additional identification of patients with pCR. @*Conclusion@#AND combination of T2WI and DWI is an appropriate strategy for suggesting CR using visual assessment of MRI after CRT for rectal cancer.
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Purpose@#The outcomes of non-trauma patients requiring intra-abdominal gauze packing for the management of uncontrollable hemorrhage following surgery, and the evaluation of survival risk factors were examined. @*Methods@#Data from patients who underwent intra-abdominal gauze packing to control bleeding during abdominal surgery between September 2012 and March 2019 were retrospectively reviewed. @*Results@#A total of 28 patients were included in the study population analysis. There were 9 patients who died during hospitalization. One patient died as a result of uncontrolled bleeding. In spite of gauze packing, 2 patients who had increasing blood transfusion requirements (> 4 packs/4 hours) were found to have arterial bleeding. Univariate analysis for hospital death showed that immunocompromised status, emergency surgery, a thrombocytopenic state prior to initial surgery, and a longer duration until gauze removal had a negative association with survival outcomes. Among these factors, only time to gauze removal > 36 hours was identified as an independent risk factor for survival outcome in the multivariate analysis. @*Conclusions@#Gauze packing could be considered as an effective method for the management of uncontrolled hemorrhage, in non-trauma patients. In cases of persistent bleeding after gauze packing, arterial bleeding should be suspected. Gauze removal after > 36 hours may indicate a poor survival outcome.
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Few radiation-induced bowel perforations have been reported to date. Furthermore, perforation after ileal restoration in asymptomatic patients is rare. We report the case of a 61-year-old man who was administered preoperative chemoradiotherapy for advanced rectal cancer. The patient underwent ultra-low anterior resection with ileal diversion, followed by ileal restoration. Perforation was detected 9 days after restoration, and he underwent a right hemicolectomy. The histologic evaluation indicated ileal perforation caused by acute radiation enteritis.
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Objective@#Adequate methods of combining T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) to assess complete response (CR) to chemoradiotherapy (CRT) for rectal cancer are obscure. We aimed to determine an algorithm for combining T2WI and DWI to optimally suggest CR on MRI using visual assessment. @*Materials and Methods@#We included 376 patients (male:female, 256:120; mean age ± standard deviation, 59.7 ± 11.1 years) who had undergone long-course CRT for rectal cancer and both pre- and post-CRT high-resolution rectal MRI during 2017– 2018. Two experienced radiologists independently evaluated whether a tumor signal was absent, representing CR, on both post-CRT T2WI and DWI, and whether the pre-treatment DWI showed homogeneous hyperintensity throughout the lesion. Algorithms for combining T2WI and DWI were as follows: ‘AND,’ if both showed CR; ‘OR,’ if any one showed CR; and ‘conditional OR,’ if T2WI showed CR or DWI showed CR after the pre-treatment DWI showed homogeneous hyperintensity. Their efficacies for diagnosing pathologic CR (pCR) were determined in comparison with T2WI alone. @*Results@#Sixty-nine patients (18.4%) had pCR. AND had a lower sensitivity without statistical significance (vs. 62.3% [43/69]; 59.4% [41/69], p = 0.500) and a significantly higher specificity (vs. 87.0% [267/307]; 90.2% [277/307], p = 0.002) than those of T2WI. Both OR and conditional OR combinations resulted in a large increase in sensitivity (vs. 62.3% [43/69]; 81.2% [56/69], p < 0.001; and 73.9% [51/69], p = 0.008, respectively) and a large decrease in specificity (vs. 87.0% [267/307]; 57.0% [175/307], p < 0.001; and 69.1% [212/307], p < 0.001, respectively) as compared with T2WI, ultimately creating additional false interpretations of CR more frequently than additional identification of patients with pCR. @*Conclusion@#AND combination of T2WI and DWI is an appropriate strategy for suggesting CR using visual assessment of MRI after CRT for rectal cancer.
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Purpose@#The outcomes of non-trauma patients requiring intra-abdominal gauze packing for the management of uncontrollable hemorrhage following surgery, and the evaluation of survival risk factors were examined. @*Methods@#Data from patients who underwent intra-abdominal gauze packing to control bleeding during abdominal surgery between September 2012 and March 2019 were retrospectively reviewed. @*Results@#A total of 28 patients were included in the study population analysis. There were 9 patients who died during hospitalization. One patient died as a result of uncontrolled bleeding. In spite of gauze packing, 2 patients who had increasing blood transfusion requirements (> 4 packs/4 hours) were found to have arterial bleeding. Univariate analysis for hospital death showed that immunocompromised status, emergency surgery, a thrombocytopenic state prior to initial surgery, and a longer duration until gauze removal had a negative association with survival outcomes. Among these factors, only time to gauze removal > 36 hours was identified as an independent risk factor for survival outcome in the multivariate analysis. @*Conclusions@#Gauze packing could be considered as an effective method for the management of uncontrolled hemorrhage, in non-trauma patients. In cases of persistent bleeding after gauze packing, arterial bleeding should be suspected. Gauze removal after > 36 hours may indicate a poor survival outcome.
الملخص
Few radiation-induced bowel perforations have been reported to date. Furthermore, perforation after ileal restoration in asymptomatic patients is rare. We report the case of a 61-year-old man who was administered preoperative chemoradiotherapy for advanced rectal cancer. The patient underwent ultra-low anterior resection with ileal diversion, followed by ileal restoration. Perforation was detected 9 days after restoration, and he underwent a right hemicolectomy. The histologic evaluation indicated ileal perforation caused by acute radiation enteritis.
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Purpose@#We evaluated the association of body composition with long-term oncologic outcomes innon-metastatic rectal cancer patients. @*Materials and Methods@#We included 1,384 patients with stage(y)0-III rectal cancer treated at Asan Medical Centerbetween January 2005 and December 2012. Body composition at diagnosis was measuredusing abdomino-pelvic computed tomography (CT). Sarcopenia, visceral obesity (VO), andsarcopenic obesity (SO) were defined using CT measured parameters such as skeletal muscleindex (total abdominal muscle area, TAMA), visceral fat area (VFA), and VFA/TAMA. Inflammatorystatus was defined as a neutrophil-lymphocyte ratio of ! 3. Obesity was categorizedby body mass index (! 25 kg/m2). @*Results@#Among the 1,384 patients, 944 (68.2%) had sarcopenia and 307 (22.2%) had SO. The5-year overall survival (OS) rate was significantly lower in sarcopenic patients (no sarcopeniavs. sarcopenia; 84% vs. 78%, p=0.003) but the 5-year recurrence-free survival (RFS) ratewas not different (77.3% vs. 77.9% p=0.957). Patients with SO showed lower 5-year OS(79.1% vs. 75.5% p=0.02) but no difference in 5-year RFS (p=0.957). Sarcopenia, SO, VO,and obesity were not associated with RFS. However, obesity, SO, age, sex, inflammatorystatus, and tumor stage were confirmed as independent factors associated with OS on multivariateanalysis. In subgroup analysis, association of SO with OS was more prominent inpatients with (y)p stage 0-2 and no inflammatory status. @*Conclusion@#The presence of SO and a low body mass index at diagnosis are negatively associated withOS in non-metastatic rectal cancer patients.
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Purpose@#This study aimed to compare the short-term outcomes of the open and laparoscopic approaches to 2-stage restorative proctocolectomy (RPC) for Korean patients with ulcerative colitis (UC). @*Methods@#We retrospectively analyzed the medical records of 73 patients with UC who underwent elective RPC between 2009 and 2016. Patient characteristics, operative details, and postoperative complications within 30 days were compared between the open and laparoscopic groups. @*Results@#There were 26 cases (36%) in the laparoscopic group, which had a lower mean body mass index (P = 0.025), faster mean time to recovery of bowel function (P = 0.004), less intraoperative blood loss (P = 0.004), and less pain on the first and seventh postoperative days (P = 0.029 and P = 0.027, respectively) compared to open group. There were no deaths, and the overall complication rate was 43.8%. There was no between-group difference in the overall complication rate; however, postoperative ileus was more frequent in the open group (27.7% vs. 7.7%, P = 0.043). Current smoking (odds ratio [OR], 44.4; P = 0.003) and open surgery (OR, 5.4; P = 0.014) were the independent risk factors for postoperative complications after RPC. @*Conclusion@#Laparoscopic RPC was associated with acceptable morbidity and faster recovery than the open approach. The laparoscopic approach is a feasible and safe option for surgical treatment for UC in selective cases.
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Purpose@#Upper gastrointestinal (GI) tract involvement in Crohn disease (CD) is rare and effectiveness of surgical treatment is limited. The aim of this study was to evaluate characteristics and surgical outcomes of upper GI CD. @*Methods@#Medical records of 811 patients who underwent intestinal surgery for CD between January 2006 and December 2015 at a single institution were reviewed. Upper GI CD was defined by involvement of the stomach to the fourth portion of duodenum, with or without concomitant small/large bowel CD involvement according to a modification of the Montreal classification. @*Results@#We identified 24 patients (21 males, 3 females) who underwent surgery for upper GI CD. The mean age at diagnosis was 27 ± 12 years, the mean age at surgery was 33 ± 11 years, and the mean duration of CD was 73.6 ± 56.6 months.Fifteen patients (62.5%) had history of previous perianal surgery. Ten patients (41.7%) had duodenal or gastric stricture and 14 patients (58.3%) had penetrating fistula; patients with fistula were significantly more likely to develop complications (57.1% vs. 20.0%, P = 0.035). One patient with stricture had surgical recurrence. In seven patients with fistula, fistula was related to previous anastomosis. Patients with fistula had significantly longer hospital stays than those with stricture (16 days vs. 11 days, P = 0.01). @*Conclusion@#Upper GI CD is rare among CD types (2.96%). In patients with upper GI CD, penetrating fistula was associated with longer hospital stay and more complications.
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PURPOSE: The rare incidence of isolated para-aortic lymph node (PALN) recurrence of colorectal cancer has precluded the formulation of treatment guidelines. This study evaluated and compared the effects of different treatment modalities on survival outcomes in patients with PALN recurrence.METHODS: Patients diagnosed with isolated PALN recurrence after curative resection for primary colorectal cancer from January 2004 to December 2014 were evaluated retrospectively. Patients with isolated recurrence were selected using imaging modalities. Overall survival (OS) and survival after recurrence (SAR) were analyzed and compared between different treatments using the Kaplan-Meier method.RESULTS: The median OS was 64 months with a median follow-up time of 50 months. Of the 46 patients with PALN recurrence, 35 (76.1%) had isolated recurrences. Of these 35 patients, 16 underwent PALN resection and 19 received chemotherapy. Median SAR was significantly longer in patients who did than did not undergo resection (71 months vs. 39 months, P = 0.017). Median OS tended to be longer in patients who did than did not undergo resection (77 months vs. 62 months, P = 0.055). SAR was similar in patients who received radiotherapy and those who underwent resection (34 months vs. 46 months, P = 0.146). Three of 16 patients (18.8%) who underwent resection were found to be recurrence-free.CONCLUSION: Surgical resection of isolated PALN recurrence may benefit patients, with favorable survival outcomes and by providing definitive diagnosis for proper treatment planning.
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Humans , Colorectal Neoplasms , Diagnosis , Drug Therapy , Follow-Up Studies , Incidence , Lymph Node Excision , Lymph Nodes , Methods , Mortality , Radiotherapy , Recurrence , Retrospective Studiesالملخص
PURPOSE: As robotic surgery is increasingly performed in patients with colorectal diseases, understanding proper port placement for robotic colorectal surgery is necessary. This review summarizes current port placement during robotic surgery for colorectal diseases and provides future perspective on port placements.METHODS: PubMed were searched from January 2009 to December 2018 using a combination of the search terms “robotic” [MeSH], “colon” [MeSH], “rectum” [MeSH], “colorectal” [MeSH], and “colorectal surgery” [MeSH]. Studies related to port placement were identified and included in the current study if they used the da Vinci S, Si, or Xi robotic system and if they described port placement.RESULTS: This review included 77 studies including a total of 3,145 operations. Fifty studies described port placement for left-sided and mesorectal excision; 17, 3, and 7 studies assessed port placement for right-sided colectomy, rectopexy, transanal surgery, respectively; and one study assessed surgery with reduced port placement. Recent literatures show that the single-docking technique included mobilization of the second and third robotic arms for the different parts without movement of patient cart and similar to previous dual or triple-docking technique. Besides, use of the da Vinci Xi system allowed a more simplified port configuration.CONCLUSION: Robot-assisted colorectal surgery can be efficiently achieved with successful port placement without movement of patient cart dependent on the type of surgery and the robotic system.
الموضوعات
Humans , Arm , Colectomy , Colon , Colorectal Surgery , Rectum , Robotic Surgical Procedures , Roboticsالملخص
Purpose@#Recurrence patterns in rectal cancer patients treated with preoperative chemoradiotherapy (PCRT) are needed to evaluate for establishing tailored surveillance protocol. @*Methods@#This study included 2,215 patients with locally-advanced mid and low rectal cancer treated with radical resection between January 2005 and December 2012. Recurrence was evaluated according to receipt of PCRT; PCRT group (n = 1,258) and no-PCRT group (n = 957). Early recurrence occurred within 1 year of surgery and late recurrence after 3 years. The median follow-up duration was 65.7 ± 29 months. @*Results@#The overall recurrence rate was similar between the PCRT and no-PCRT group (25.8% vs. 24.9%, P = 0.622). The most common initial recurrence site was the lungs in both groups (50.6% vs. 49.6%, P = 0.864), followed by the liver, which was more common in the no-PCRT group (22.5% vs. 33.6%, P = 0.004). Most of the recurrence occurred within 3 years after surgery in both groups (85.3% vs. 85.8%, P = 0.862). Early recurrence was more common in the PCRT group than in the no-PCRT group (43.1% vs. 32.4%, P = 0.020). Recurrence within the first 6 months after surgery was significantly higher in the PCRT group than in the no-PCRT group (18.8% vs. 7.6%, P = 0.003). Lung (n = 27, 44.3%) and liver (n = 22, 36.1%) were the frequent the first relapsed site within 6 months after surgery in PCRT group. @*Conclusion@#Early recurrence within the first 1 year after surgery was more common in patients treated with PCRT. This difference would be considered for surveillance protocols and need to be evaluated in further studies.
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Purpose@#Recurrence patterns in rectal cancer patients treated with preoperative chemoradiotherapy (PCRT) are needed to evaluate for establishing tailored surveillance protocol. @*Methods@#This study included 2,215 patients with locally-advanced mid and low rectal cancer treated with radical resection between January 2005 and December 2012. Recurrence was evaluated according to receipt of PCRT; PCRT group (n = 1,258) and no-PCRT group (n = 957). Early recurrence occurred within 1 year of surgery and late recurrence after 3 years. The median follow-up duration was 65.7 ± 29 months. @*Results@#The overall recurrence rate was similar between the PCRT and no-PCRT group (25.8% vs. 24.9%, P = 0.622). The most common initial recurrence site was the lungs in both groups (50.6% vs. 49.6%, P = 0.864), followed by the liver, which was more common in the no-PCRT group (22.5% vs. 33.6%, P = 0.004). Most of the recurrence occurred within 3 years after surgery in both groups (85.3% vs. 85.8%, P = 0.862). Early recurrence was more common in the PCRT group than in the no-PCRT group (43.1% vs. 32.4%, P = 0.020). Recurrence within the first 6 months after surgery was significantly higher in the PCRT group than in the no-PCRT group (18.8% vs. 7.6%, P = 0.003). Lung (n = 27, 44.3%) and liver (n = 22, 36.1%) were the frequent the first relapsed site within 6 months after surgery in PCRT group. @*Conclusion@#Early recurrence within the first 1 year after surgery was more common in patients treated with PCRT. This difference would be considered for surveillance protocols and need to be evaluated in further studies.
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Currently, Illumina sequencers are the globally leading sequencing platform in the next-generation sequencing market. Recently, MGI Tech launched a series of new sequencers, including the MGISEQ-2000, which promise to deliver high-quality sequencing data faster and at lower prices than Illumina’s sequencers. In this study, we compared the performance of two major sequencers (MGISEQ-2000 and HiSeq 4000) to test whether the MGISEQ-2000 sequencer delivers high-quality sequence data as suggested. We performed RNA sequencing of four human colon cancer samples with the two platforms, and compared the sequencing quality and expression values. The data produced from the MGISEQ-2000 and HiSeq 4000 showed high concordance, with Pearson correlation coefficients ranging from 0.98 to 0.99. Various quality control (QC) analyses showed that the MGISEQ-2000 data fulfilled the required QC measures. Our study suggests that the performance of the MGISEQ-2000 is comparable to that of the HiSeq 4000 and that the MGISEQ-2000 can be a useful platform for sequencing.
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Humans , Benchmarking , Colonic Neoplasms , Quality Control , RNA , Sequence Analysis, RNAالملخص
PURPOSE: Extranodal extension (ENE) is closely associated with the aggressiveness of both colon and rectal cancer. This study evaluated the clinicopathologic significance and prognostic impact of ENE in separate populations of patients with colon and rectal cancers. MATERIALS AND METHODS: The medical records of 2,346 patients with colorectal cancer (CRC) who underwent curative surgery at our institution between January 2003 and December 2011 were clinically and histologically reviewed. RESULTS: ENE was associated with younger age, advanced tumor stage, lymphovascular invasion (LVI), and perineural invasion (PNI) in both colon and rectal cancer. ENE rates differed significantly in patients with right colon (36.9%), left colon (42.6%), and rectal (48.7%) cancers (right vs. left, p=0.037; left vs. rectum, p=0.009). The 5-year disease-free survival (DFS) rate according to ENE status and primary tumor site differed significantly in patients with ENE-negative colon cancer (80.5%), ENE-negative rectal cancer (77.4%), ENE-positive colon cancer (68.6%), and ENE-positive rectal cancer (64.2%) (p<0.001). Multivariate analysis showed that advanced tumor stage, ENE, LVI, PNI, and absence of adjuvant chemotherapy were independently prognostic of reduced DFS in colon and rectal cancer patients. CONCLUSION: ENE is closely associated with the aggressiveness of colon and rectal cancers, with its frequency increasing from the right colon to the left colon to the rectum. ENE status is a significant independent predictor of DFS in CRC patients irrespective of tumor location. ENE might be more related with distally located CRC.