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Background@#and Purpose The relationship between napping and cognition remains controversial. This study aimed to investigate the association between napping and cognition according to sleep debt in the Korean adult population. @*Methods@#A population-based nationwide cross-sectional survey was conducted in 2018. A two-stage stratified random sample of Koreans aged ≥19 years was selected and evaluated using questionnaires by trained interviewers. Cognitive function was assessed using the Mail-In Cognitive Function Screening Instrument (MCFSI). Sleep habits on weekdays and weekends, napping, and subjective sleep requirements were assessed using the questionnaires. Accumulated sleep debt was calculated by subtracting the weekly average sleep duration from subjective sleep requirements. Sleep quality, daytime sleepiness, insomnia, depression, demographics, and comorbidities were assessed. Participants were grouped into those with sleep debt ≤60 min and those with sleep debt >60 min. Multiple linear regression was used to estimate the independent association between the factors and cognition. @*Results@#In total, 2,501 participants were included in the analysis. Naps were reported in 726 (29.0%) participants (nappers). The mean MCFSI score was higher in nappers (3.4±3.6) than in non-nappers (2.3±3.0) (p60 min of napping was associated with better cognitive function in participants with sleep debts >60 min. @*Conclusions@#In general, naps are associated with worse cognitive function in the Korean adult population. However, for those with sleep debt of >60 min, naps for >60 min were associated with better cognitive function.f
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Background/Aims@#Small rectal neuroendocrine tumors (NETs) are often managed with local resection (endoscopic or transanal excision) owing to their low risk of metastasis and recurrence. However, the clinical significance of lymphovascular invasion in resected specimens remains controversial. In this study, we aimed to analyze the frequency of and risk factors for lymph node metastasis proven by histopathologic examination after radical resection. @*Methods@#We retrospectively reviewed the records of 750 patients diagnosed with a rectal NET at four academic medical centers in South Korea between 2001 and 2019. The frequency of histopathologically proven lymph node metastasis and the associated risk factors were analyzed for small tumors (≤1.5 cm) with lymphovascular invasion. @*Results@#Among 750 patients, 75 had a small tumor (≤1.5 cm) with lymphovascular invasion, of whom 31 patients underwent endoscopic resection only and 44 patients underwent additional radical surgery. Among the 41 patients who underwent surgery and had available data, the rate of regional lymph node metastasis was 48.8% (20/41). In multivariate analysis, the Ki-67 index (odds ratio, 6.279; 95% confidence interval, 1.212 to 32.528; p=0.029) was an independent risk factor for lymph node metastasis. During the mean follow-up period of 37.7 months, only one case of recurrence was detected in the surgery group. The overall survival was not significantly different between radical resection and local resection (p=0.332). @*Conclusions@#Rectal NETs with lymphovascular invasion showed a significantly high rate of regional lymph node metastasis despite their small size (≤1.5 cm).
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Although the understanding of appendiceal mucinous neoplasms (AMNs) and their relationship with disseminated peritoneal mucinous disease have advanced, the diagnosis, classification, and treatment of AMNs are still confusing for pathologists and clinicians. The Gastrointestinal Pathology Study Group of the Korean Society of Pathologists (GPSG-KSP) proposed a multicenter study and held a workshop for the “Standardization of the Pathologic Diagnosis of the Appendiceal Mucinous Neoplasm” to overcome the controversy and potential conflicts. The present article is focused on the diagnostic criteria, terminologies, tumor grading, pathologic staging, biologic behavior, treatment, and prognosis of AMNs and disseminated peritoneal mucinous disease. In addition, GPSG-KSP proposes a checklist of standard data elements of appendiceal epithelial neoplasms to standardize pathologic diagnosis. We hope the present article will provide pathologists with updated knowledge on how to handle and diagnose AMNs and disseminated peritoneal mucinous disease.
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Purpose@#The effect of transanal total mesorectal excision (TaTME) on patients’ quality of life and functional outcomes is not fully understood. This study aimed to compare the quality of life and bowel, anorectal, and urogenital functions after laparoscopic and TaTME. @*Methods@#Laparoscopic or TaTME was performed for 202 propensity score-matched patient pairs with rectal cancer between January 2014 and December 2017 at the National Cancer Center, Korea. The outcomes for all patients were assessed using anorectal manometry, the European Organization for Research and Treatment of Cancer (EORTC) Core Quality of Life Questionnaire (QLQ-C30) and Colorectal Cancer-Specific Quality of Life Questionnaire (QLQ-CR38), low anterior resection syndrome (LARS) score, Fecal Incontinence Severity Index, and International Prostate Symptom Score (IPSS). This retrospective comparative study included patients who completed anorectal manometry and the questionnaires before treatment and at 1 year after surgery. @*Results@#The EORTC QLQ-C30 and QLQ-CR38 showed comparable outcomes regarding the quality of life in both groups. More patients experienced major LARS in the transanal group at 1 year postoperatively (31.0% vs. 6.8% in the laparoscopic group, P = 0.004). Multivariable analysis revealed no significant difference in the LARS score between the groups at 1 year postoperatively (odds ratio, 2.30; 95% confidence interval, 0.79–6.72; P = 0.127). Significant differences in the IPSS were not noted between the groups. @*Conclusion@#The quality of life and functional outcomes were comparable between the laparoscopic and transanal approaches; however, our findings suggest a higher rate of LARS after TaTME.
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Purpose@#This study was performed to evaluate the risk of readmission in the first year after low anterior resection (LAR) for patients with rectal cancer and to identify the contributing factors for readmission related to dehydration specifically. @*Methods@#This was a retrospective analysis of 570 patients who underwent LAR for rectal cancer at National Cancer Center, Republic of Korea. A diverting loop ileostomy was performed in 357 (62.6%) of these patients. Readmission was defined as an unplanned visit to the emergency room or admission to the ward. The reasons for readmission were reviewed and compared between the ileostomy (n = 357) and no-ileostomy (n = 213) groups. The risk factors for readmission and readmission due to dehydration were analyzed using multivariable logistic and Cox proportional hazard model. @*Results@#Dehydration was the most common cause of readmission in both groups (ileostomy group, 6.7%, and no-ileostomy group, 4.7%, P = 0.323). On multivariable analysis, risk factors for readmission were an estimated intraoperative blood loss of ≥400 mL (odds ratio [OR], 1.757; 95% confidence interval [CI], 1.058–2.918; P = 0.029), and postoperative chemotherapy (OR, 2.914; 95% CI, 1.824–4.653; P < 0.001). On multivariable analysis, postoperative chemotherapy, and not a diverting loop ileostomy, was an independent risk factor for dehydration-related readmission (OR, 5.102; 95% CI, 1.772–14.688; P = 0.003). @*Conclusion@#The most common cause of readmission after LAR for rectal cancer was dehydration, as reported previously. Postoperative chemotherapy, not the creation of a diverting ileostomy, was identified as the risk factor associated with readmission related to dehydration.
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Although the understanding of appendiceal mucinous neoplasms (AMNs) and their relationship with disseminated peritoneal mucinous disease have advanced, the diagnosis, classification, and treatment of AMNs are still confusing for pathologists and clinicians. The Gastrointestinal Pathology Study Group of the Korean Society of Pathologists (GPSG-KSP) proposed a multicenter study and held a workshop for the “Standardization of the Pathologic Diagnosis of the Appendiceal Mucinous Neoplasm” to overcome the controversy and potential conflicts. The present article is focused on the diagnostic criteria, terminologies, tumor grading, pathologic staging, biologic behavior, treatment, and prognosis of AMNs and disseminated peritoneal mucinous disease. In addition, GPSG-KSP proposes a checklist of standard data elements of appendiceal epithelial neoplasms to standardize pathologic diagnosis. We hope the present article will provide pathologists with updated knowledge on how to handle and diagnose AMNs and disseminated peritoneal mucinous disease.
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Purpose@#The effect of transanal total mesorectal excision (TaTME) on patients’ quality of life and functional outcomes is not fully understood. This study aimed to compare the quality of life and bowel, anorectal, and urogenital functions after laparoscopic and TaTME. @*Methods@#Laparoscopic or TaTME was performed for 202 propensity score-matched patient pairs with rectal cancer between January 2014 and December 2017 at the National Cancer Center, Korea. The outcomes for all patients were assessed using anorectal manometry, the European Organization for Research and Treatment of Cancer (EORTC) Core Quality of Life Questionnaire (QLQ-C30) and Colorectal Cancer-Specific Quality of Life Questionnaire (QLQ-CR38), low anterior resection syndrome (LARS) score, Fecal Incontinence Severity Index, and International Prostate Symptom Score (IPSS). This retrospective comparative study included patients who completed anorectal manometry and the questionnaires before treatment and at 1 year after surgery. @*Results@#The EORTC QLQ-C30 and QLQ-CR38 showed comparable outcomes regarding the quality of life in both groups. More patients experienced major LARS in the transanal group at 1 year postoperatively (31.0% vs. 6.8% in the laparoscopic group, P = 0.004). Multivariable analysis revealed no significant difference in the LARS score between the groups at 1 year postoperatively (odds ratio, 2.30; 95% confidence interval, 0.79–6.72; P = 0.127). Significant differences in the IPSS were not noted between the groups. @*Conclusion@#The quality of life and functional outcomes were comparable between the laparoscopic and transanal approaches; however, our findings suggest a higher rate of LARS after TaTME.
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Purpose@#This study was performed to evaluate the risk of readmission in the first year after low anterior resection (LAR) for patients with rectal cancer and to identify the contributing factors for readmission related to dehydration specifically. @*Methods@#This was a retrospective analysis of 570 patients who underwent LAR for rectal cancer at National Cancer Center, Republic of Korea. A diverting loop ileostomy was performed in 357 (62.6%) of these patients. Readmission was defined as an unplanned visit to the emergency room or admission to the ward. The reasons for readmission were reviewed and compared between the ileostomy (n = 357) and no-ileostomy (n = 213) groups. The risk factors for readmission and readmission due to dehydration were analyzed using multivariable logistic and Cox proportional hazard model. @*Results@#Dehydration was the most common cause of readmission in both groups (ileostomy group, 6.7%, and no-ileostomy group, 4.7%, P = 0.323). On multivariable analysis, risk factors for readmission were an estimated intraoperative blood loss of ≥400 mL (odds ratio [OR], 1.757; 95% confidence interval [CI], 1.058–2.918; P = 0.029), and postoperative chemotherapy (OR, 2.914; 95% CI, 1.824–4.653; P < 0.001). On multivariable analysis, postoperative chemotherapy, and not a diverting loop ileostomy, was an independent risk factor for dehydration-related readmission (OR, 5.102; 95% CI, 1.772–14.688; P = 0.003). @*Conclusion@#The most common cause of readmission after LAR for rectal cancer was dehydration, as reported previously. Postoperative chemotherapy, not the creation of a diverting ileostomy, was identified as the risk factor associated with readmission related to dehydration.
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Purpose@#This study was performed to evaluate the quality of life and genitourinary function after total mesorectal excision with lateral lymph node dissection compared to those after total mesorectal excision alone following neoadjuvant chemoradiotherapy for rectal cancer. @*Methods@#Among patients who underwent rectal cancer surgery after completing neoadjuvant chemoradiotherapy between September 2011 and October 2018 at the National Cancer Center, Korea, patients who completed the validated questionnaires before initiation of neoadjuvant chemoradiotherapy and at 3 months and 1 year postoperatively were included in this study. The European Organization for Research and Treatment of Cancer (EORTC) core quality of life questionnaire (QLQ-C30), colorectal cancer-specific quality of life questionnaire (QLQ-CR38), and International Prostate Symptom Score (IPSS) questionnaire were used for collecting data. @*Results@#The total mesorectal excision alone group and the total mesorectal excision with lateral lymph node dissection group included 52 and 38 patients, respectively. The second group included significantly younger patients (P = 0.024), had a higher incidence of clinical T4 stage disease (P = 0.033), estimated blood loss (P = 0.003), and longer operation time (P < 0.001). Significant differences were not observed between the groups with respect to the EORTC QLQ-C30, QLQ-CR38, and IPSS. Multivariable analysis showed that lateral lymph node dissection had no statistically significant association with postoperative urinary dysfunction (P = 0.953). @*Conclusion@#The overall quality of life and urinary function after total mesorectal excision does not differ significantly when lateral lymph node dissection is performed as well.
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Objectives@#The aim of this study is to evaluate relationship of health-related quality of life (HRQoL) with chronotype along with quality and quantity of sleep in Korean middle adults. @*Methods@#Data was derived from the nationwide, cross-sectional study on sleep surveyed 2,501 representative adult Koreans. We collected data from 1,435 participants aged ≥35 years and <65 years to represent Korean middle adults. The Chronotype Questionnaire was used to assess phase and distinctiveness of the circadian rhythm. The Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. Quantity of sleep was investigated by questions regarding sleep habits during workdays and free days. EuroQol-5D 3-level version was used to measure HRQoL. @*Results@#On univariable analyses, eveningness is associated with younger age (47.7±8.2 vs. 51.3±8.1 years, p<0.001), and higher PSQI total score (4.3±2.7 vs. 3.6±2.2, p<0.001) compared with morningness. Strong distinctiveness also associated with higher PSQI total score (4.2±2.3 vs. 3.6±2.5, p< 0.001) compared with weak distinctiveness. Age was not different between the two groups of distinctiveness. On multivariable analyses, strong distinctiveness is an independent factor predicting impairment of pain/discomfort [odd ratio (OR) 1.589, 95% confidence interval (CI) 1.182–2.130] and depression/anxiety (OR 1.412, 95% CI 1.003–1.987). Poor sleep quality was the most powerful independent factor predicting impairments in all five domains of the HRQoL. @*Conclusions@#Sleep quality is an important factor independently related to the HRQoL. Among chronotype variables, only distinctiveness has an independent relation with the HRQoL.
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Hereditary myopathy with early respiratory failure (HMERF) is characterized by early respiratory insufficiency which is inappropriate to the degree of limb muscle weakness. Recently, mutation in TTN gene was found in HMERF patients with the aid of gene sequencing. We describe the first case presenting with distal leg weakness and early respiratory failure confirmed by TTN gene mutation in Korea.
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The first edition of the ‘Standardized Pathology Report for Colorectal Cancer,’ which was developed by the Gastrointestinal Pathology Study Group (GIP) of the Korean Society of Pathologists, was published 13 years ago. Meanwhile, there have been many changes in the pathologic diagnosis of colorectal cancer (CRC), pathologic findings included in the pathology report, and immunohistochemical and molecular pathology required for the diagnosis and treatment of colorectal cancer. In order to reflect these changes, we (GIP) decided to make the second edition of the report. The purpose of this standardized pathology report is to provide a practical protocol for Korean pathologists, which could help diagnose and treat CRC patients. This report consists of “standard data elements” and “conditional data elements.” Basic pathologic findings and parts necessary for prognostication of CRC patients are classified as “standard data elements,” while other prognostic factors and factors related to adjuvant therapy are classified as “conditional data elements” so that each institution could select the contents according to the characteristics of the institution. The Korean version is also provided separately so that Korean pathologists can easily understand and use this report. We hope that this report will be helpful in the daily practice of CRC diagnosis.
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Purpose@#Mutation of the Kirsten Ras (KRAS) oncogene is present in 30%-40% of colorectal cancers and has prognostic significance in rectal cancer. In this study, we examined the ability of radiomics features extracted from T2-weighted magnetic resonance (MR) images to differentiate between tumors with mutant KRAS and wild-type KRAS. @*Materials and Methods@#Sixty patients with primary rectal cancer (25 with mutant KRAS, 35 with wild-type KRAS) were retrospectively enrolled. Texture analysis was performed in all regions of interest on MR images, which were manually segmented by two independent radiologists. We identified potentially useful imaging features using the two-tailed t test and used them to build a discriminant model with a decision tree to estimate whether KRAS mutation had occurred. @*Results@#Three radiomic features were significantly associated with KRASmutational status (p < 0.05). The mean (and standard deviation) skewness with gradient filter value was significantly higher in the mutant KRAS group than in the wild-type group (2.04±0.94 vs. 1.59±0.69). Higher standard deviations for medium texture (SSF3 and SSF4) were able to differentiate mutant KRAS (139.81±44.19 and 267.12±89.75, respectively) and wild-type KRAS (114.55±29.30 and 224.78±62.20). The final decision tree comprised three decision nodes and four terminal nodes, two of which designated KRAS mutation. The sensitivity, specificity, and accuracy of the decision tree was 84%, 80%, and 81.7%, respectively. @*Conclusion@#Using MR-based texture analysis, we identified three imaging features that could differentiate mutant from wild-type KRAS. T2-weighted images could be used to predict KRAS mutation status preoperatively in patients with rectal cancer.
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Purpose@#Minute T1 colorectal cancer (CRC) lesions (≤5 mm) are rare; however, little is known about their characteristics and aggressiveness. In this study, we evaluated the characteristics of minute T1 CRC in relevance to pathology and treatment. @*Methods@#This retrospective study included 849 patients with T1 CRC endoscopically or surgically treated between January 2001 and December 2016. The patients were stratified into 4 groups according to tumor size; minute group (≤5 mm), small group (6–10 mm), medium group (11–20 mm), and large group (≥21 mm). Clinicopathological variables were evaluated with respect to tumor size. @*Results@#The incidence of the minute T1 CRC was 2.4% (20 of 849). Minute T1 CRC was significantly associated with flat type (minute, 25%; small, 12.6%; medium, 8.8%; large, 12.6%; P = 0.016), right-sided cancer (30%, 15.4%, 15.4%, 15.1%, P = 0.002) and the absence of background adenoma (BGA) (50%, 40.7%, 32.8%, 18.1%, P < 0.001). In patients who underwent surgery, lymph node metastasis (LNM) was significantly higher in the minute group (36.4%, 15.9%, 15.7%, 9.2%, P = 0.029). @*Conclusion@#Minute T1 CRC is significantly associated with flat type, right-sided cancers, as well as with the absence of BGA and LNM. These results suggested the minute T1 CRC lesions are often aggressive and are likely to be missed during colonoscopy.
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PURPOSE: To assess the feasibility of transanal total mesorectal excision in difficult cases including obese patients or patients with bulky tumors or threatened mesorectal fascias. METHODS: We performed laparoscopy-assisted transanal total mesorectal excision in patients with biopsy-proven rectal adenocarcinoma located 3–12 cm from the anal verge as part of a prospective, single arm, pilot trial. The primary endpoint was resection quality and circumferential resection margin involvement. Secondary endpoints included the number of harvested lymph nodes and 30-day postoperative complications. RESULTS: A total of 12 patients (9 men and 3 women) were enrolled: one obese patient, 7 with large tumors and 8 with threatened mesorectal fascias (4 patients had multiple indications). Tumors were located a median of 5.5 cm from the anal verge, and all patients received preoperative chemoradiotherapy. Median operating time was 191 minutes, and there were no intraoperative complications. One patient needed conversion to open surgery for ureterocystostomy after en bloc resection. Complete or near-complete excision and negative circumferential resection margins were achieved in all cases. The median number of harvested lymph nodes was 15.5. There was no postoperative mortality and 3 cases of postoperative morbidity (1 postoperative ileus, 1 wound problem near the stoma site, and 1 anastomotic dehiscence). CONCLUSION: This pilot study showed that transanal total mesorectal excision is also feasible in difficult laparoscopic cases such as in obese patients or those with bulky tumors or tumors threatening the mesorectal fascia. Additional larger studies are needed.
Subject(s)
Humans , Male , Adenocarcinoma , Arm , Chemoradiotherapy , Conversion to Open Surgery , Fascia , Ileus , Intraoperative Complications , Laparoscopy , Lymph Nodes , Mortality , Pilot Projects , Postoperative Complications , Prospective Studies , Rectal Neoplasms , Transanal Endoscopic Surgery , Wounds and InjuriesABSTRACT
Opalski syndrome is a rare lateral medullary infarction variant presenting with ipsilateral motor deficits known to be caused by involvement of the post-decussating pyramidal tract. Here, we report two rare cases of Opalski syndrome presenting as ipsilateral sensorimotor deficits in cerebral infarction.
Subject(s)
Cerebral Infarction , Infarction , Lateral Medullary Syndrome , Pyramidal TractsABSTRACT
PURPOSE: Predicting lymph node metastasis (LNM) risk is crucial in determining further treatment strategies following endoscopic resection of T1 colorectal cancer (CRC). This study aimed to establish a new prediction model for the risk of LNM in T1 CRC patients. MATERIALS AND METHODS: The development set included 833 patients with T1 CRC who had undergone endoscopic (n=154) or surgical (n=679) resection at the National Cancer Center. The validation set included 722 T1 CRC patients who had undergone endoscopic (n=249) or surgical (n=473) resection at Daehang Hospital. A logistic regression model was used to construct the prediction model. To assess the performance of prediction model, discrimination was evaluated using the receiver operating characteristic (ROC) curves with area under the ROC curve (AUC), and calibration was assessed using the Hosmer-Lemeshow (HL) goodness-of-fit test. RESULTS: Five independent risk factors were determined in the multivariable model, including vascular invasion, high-grade histology, submucosal invasion, budding, and background adenoma. In final prediction model, the performance of the model was good that the AUC was 0.812 (95% confidence interval [CI], 0.770 to 0.855) and the HL chi-squared test statistic was 1.266 (p=0.737). In external validation, the performance was still good that the AUC was 0.771 (95% CI, 0.708 to 0.834) and the p-value of the HL chi-squared test was 0.040. We constructed the nomogram with the final prediction model. CONCLUSION: We presented an externally validated new prediction model for LNM risk in T1 CRC patients, guiding decision making in determining whether additional surgery is required after endoscopic resection of T1 CRC.
Subject(s)
Humans , Adenoma , Area Under Curve , Calibration , Colorectal Neoplasms , Decision Making , Discrimination, Psychological , Logistic Models , Lymph Nodes , Neoplasm Metastasis , Nomograms , Risk Factors , ROC CurveABSTRACT
PURPOSE: Both genetic and lifestyle factors contribute to the risk of colorectal cancer, but each individual factor has a limited effect. Therefore, we investigated the association between colorectal cancer and the combined effects of genetic factors or/and lifestyle risk factors. MATERIALS AND METHODS: In a case-control study of 632 colorectal cancer patients and 1,295 healthy controls, we quantified the genetic risk score for colorectal cancer using 13 polymorphisms. Furthermore, we determined a combined lifestyle risk score including obesity, physical activity, smoking, alcohol consumption, and dietary inflammatory index. The associations between colorectal cancer and risk score using these factors were examined using a logistic regression model. RESULTS: Higher genetic risk scores were associated with an increased risk of colorectal cancer (odds ratio [OR], 2.57; 95% confidence interval [CI], 1.89 to 3.49 for the highest tertile vs. lowest tertile). Among the modifiable factors, previous body mass index, physical inactivity, heavy alcohol consumption, and a high inflammatory diet were associated with an increased risk of colorectal cancer. A higher lifestyle risk score was associated with an increased risk of colorectal cancer (OR, 5.82; 95% CI, 4.02 to 8.44 for the highest tertile vs. lowest tertile). This association was similar in each genetic risk category. CONCLUSION: Adherence to a healthy lifestyle is associated with a substantially reduced risk of colorectal cancer regardless of individuals’ genetic risk.
Subject(s)
Humans , Alcohol Drinking , Body Mass Index , Case-Control Studies , Colorectal Neoplasms , Diet , Life Style , Logistic Models , Motor Activity , Obesity , Risk Factors , Smoke , SmokingABSTRACT
The incidence of rectal neuroendocrine tumors (NETs) has increased worldwide, including in Korea. Rectal NETs are usually single lesions, but synchronous multiple lesions are reported in 2–4.5% of patients. Small rectal NETs (≤ 10 mm) are usually confined to the submucosal layer and rarely give rise to lymph node or distant metastases. Here we describe the case of a 54-year-old woman referred to National Cancer Center for the management of two rectal subepithelial tumors. Because computed tomography revealed a small hepatic nodule suggesting atypical hemangioma rather than metastasis, endoscopic submucosal dissection was performed. However, the size of the nodules increased during follow-up. The pathologic results of a liver biopsy confirmed metastatic NET. This case was unusual in that synchronous small rectal NETs and distant liver metastasis occurred in the absence of any risk factors for metastasis. Thus, patients with rectal NETs should be carefully evaluated, especially for the possibility of metastasis.
Subject(s)
Female , Humans , Middle Aged , Biopsy , Follow-Up Studies , Hemangioma , Incidence , Korea , Liver , Lymph Nodes , Neoplasm Metastasis , Neuroendocrine Tumors , Rectum , Risk FactorsABSTRACT
The incidence of rectal neuroendocrine tumors (NETs) has increased worldwide, including in Korea. Rectal NETs are usually single lesions, but synchronous multiple lesions are reported in 2–4.5% of patients. Small rectal NETs (≤ 10 mm) are usually confined to the submucosal layer and rarely give rise to lymph node or distant metastases. Here we describe the case of a 54-year-old woman referred to National Cancer Center for the management of two rectal subepithelial tumors. Because computed tomography revealed a small hepatic nodule suggesting atypical hemangioma rather than metastasis, endoscopic submucosal dissection was performed. However, the size of the nodules increased during follow-up. The pathologic results of a liver biopsy confirmed metastatic NET. This case was unusual in that synchronous small rectal NETs and distant liver metastasis occurred in the absence of any risk factors for metastasis. Thus, patients with rectal NETs should be carefully evaluated, especially for the possibility of metastasis.