Laparoscopic Ultralow Anterior Resection Using a New Articulating Device.

BACKGROUND: Laparoscopic surgery offers several advantages, but it can be challenging to perform in confined spaces, such as the narrow and deep pelvis, due to poor vision and instrument collisions. Conventional laparoscopic instruments are rigid and straight, which can restrict optimal access to the target organ. Although the use of robotic surgical platforms with flexible wrists has significantly reduced movement restrictions and surgeon fatigue, their high cost remains a barrier to widespread adoption. IMPACT OF INNOVATION: Recent technological advancements in laparoscopic instruments have led to the development of an articulating flexible hand-held device that enables greater dexterity and easier access to difficult anatomical locations. This technology has the potential to improve surgical outcomes by using multiple degrees of freedom to perform complex surgical procedures with greater precision. TECHNOLOGY, MATERIALS, AND METHODS: The ArtiSential® product line comprises over 30 end-effectors, such as scissors, hooks, and graspers. The benefits of this device are evident throughout the total mesorectal excision, especially when approaching the left lateral side of the mesorectum (the side opposite the surgeon) or the deepest part of the pelvis around the levator ani muscle. The Samsung Medical Center Institutional Review Board approved this study (2022-01-174). PRELIMINARY RESULTS: A 79-year-old male with rectal cancer located 9 cm from the anal verge underwent an laparoscopic ultralow anterior resection using ArtiSential®. There were no intraoperative complications. The pathologic results showed that the tumor was at pT3N0 stage. The patient was discharged without any complications. CONCLUSION AND FUTURE DIRECTIONS: The articulating device can be effectively used for laparoscopic surgery, but has some challenges related to the bulky handpiece and learning curve. A multicenter prospective cohort study to compare the outcomes of articulating laparoscopic surgery and robotic surgery for patients with rectal cancer is oncoing (clinicaltrials.gov number: NCT05566249).

Risk factors and treatment strategies for local recurrence of locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy followed by total mesorectal excision.

BACKGROUND: Despite advancements in total mesorectal excision (TME) and neoadjuvant radiotherapy, locally advanced rectal cancer remains challenging, impacting patient quality of life and mortality. This study aimed to identify the risk factors for local recurrence in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy (CRT) and assess treatment strategies for recurrence. METHODS: This retrospective analysis included 682 patients diagnosed with locally advanced rectal cancer who were treated with neoadjuvant CRT and TME at Samsung Medical Center from 2008 to 2017. The exclusion criteria ensured a homogenous cohort. Clinical staging involved colonoscopies, computed tomography, magnetic resonance imaging, and digital rectal exam. Risk factors, treatment modalities, and oncological outcomes for local recurrence were evaluated. RESULT: During a median 62-month follow-up, 47 patients (6.9 %) experienced local recurrence. The risk factors for local recurrence included a positive circumferential resection margin (CRM), venous invasion, and perineural invasion. Of the 47 patients with local recurrence, 25 (53.2 %) were considered resectable. Out of these, 23 patients underwent curative resections, and 15 (65.2 %) achieved R0 resection. Patients with R0 resections exhibited superior 5-year survival rates compared to R1-2 resection or non-surgical treatment, and there was no survival difference between R1-2 resection and non-surgical treatment. CONCLUSION: In locally advanced rectal cancer, positive CRM, venous invasion, and perineural invasion were associated with local recurrence. R0 resection showed favorable outcomes, emphasizing the importance of surveillance in high-risk patients. Treatment decisions should consider these factors for improved oncologic outcomes and quality of life.

Potential for Metastasis and Recurrence in Colorectal Carcinoma In Situ: A Retrospective Analysis of 1069 Patients.

BACKGROUND: Colorectal carcinoma in situ, characterized by cancer limited to the intramucosal layer or known as intraepithelial carcinoma, has conventionally considered to be without any risk of regional lymph node metastasis. However, isolated cases of regional lymph node metastasis, local recurrence, and distant metastasis challenge this assumption. This study aimed to assess the occurrence of regional lymph node metastasis and recurrence of colorectal carcinoma in situ. METHODS: A retrospective analysis was conducted in 1069 patients who underwent full-thickness local excision or radical surgery for colorectal carcinoma in situ between January 1994 and December 2020. Histopathological features were assessed by 2 experienced pathologists. In cases of suspected recurrence, evaluation involved abdomen-pelvis and chest computed tomography, or PET-CT. RESULTS: The recurrence rate of colorectal carcinoma in situ patients was 0.46%. Among the patients, 9 were diagnosed with regional lymph node metastasis or cancer recurrence. Of these, 4 patients were diagnosed with lymph node metastasis during primary surgery; 2 exhibited regional lymph node metastasis, and 2 presented with both regional and distant lymph node metastases. Regional lymph node metastasis occurred in additional 2 patients after radical surgery for the primary tumor. Distant metastasis was observed in 3 patients: hepatic metastasis in 1, hepatic and pulmonary metastases in another, and small bowel metastasis in the third patient. Among the 5 patients experiencing cancer recurrence, 1 expired due to cancer progression. CONCLUSION: Contrary to previous assumptions, colorectal carcinoma in situ can potentially metastasize to lymph nodes and recur. Therefore, careful assessment at the time of diagnosis is crucial, recognizing the possibility of lymph node metastasis or recurrence. This approach is essential for accurately identifying instances of cancer recurrence and ensuring optimal oncological outcomes.

Predicting survival in locally advanced rectal cancer with effective chemoradiotherapy response.

BACKGROUND: Locally advanced rectal cancer patients often display favorable responses and favorable oncologic outcomes. Due to the low recurrence rate, there is scarcity of studies investigating the prognostic factors influencing their survival. Therefore, our study sought to assess the prognostic factors associated with survival in rectal cancer patients who achieved either a pathologic complete response or a pathologic stage I after neoadjuvant chemoradiotherapy combined with radical resection. METHODS: In this retrospective study, we analyzed data from cohort of 1394 patients diagnosed with locally advanced rectal cancer who underwent neoadjuvant chemoradiotherapy combined with total mesorectal excision from January 2008 to April 2017. Finally, we selected 474 (34.2 %) who exhibited either a pathologic complete response or attained pathologic stage I following the treatment. Subsequently, we analyzed the prognostic factors influencing disease-free and overall survival. RESULTS: A total of 161 (34 %) achieved a pathologic complete response. Our analysis revealed that circumferential resection margin and the administration of adjuvant chemotherapy were prognostic factors for disease-free survival (p = 0.011, p = 0.022). Furthermore, factors influencing overall survival included the clinical N stage and administration of adjuvant chemotherapy (p = 0.035, p = 0.015). CONCLUSION: In conclusion, the circumferential resection margin, clinical N stage, and administration of adjuvant chemotherapy were prognostic factors for survival in patients showing good response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer. For patients with a positive circumferential resection margin and clinical N (+) stage, intensive follow-up might be needed to achieve favorable oncologic outcomes. Also, we recommend considering adjuvant chemotherapy as a beneficial treatment approach for these patients.

Pulmonary Metastasis as the First Site of Metastasis After Curative Surgery for Colon Cancer: Incidence and Risk Factors According to the TNM Stage.

BACKGROUND: The lungs are one of the most common sites for colon cancer metastasis. A few studies reported that approximately 2% to 10% of patients with colon cancer developed pulmonary metastasis. However, among these studies, patient characteristics were heterogeneous, and information on pulmonary metastasis incidence by the TNM stage was scarce. OBJECTIVE: This study evaluated the incidence of pulmonary metastasis in colon cancer without synchronous metastasis treated with radical surgery and identified risk factors for pulmonary metastasis according to the TNM stage. DESIGN AND SETTINGS: This retrospective study included all patients with colon cancer without metastasis who underwent radical surgery for primary tumor at Samsung Medical Center between January 2007 and December 2016. PATIENTS: A total of 4889 patients who underwent radical surgery for stage I and III colon cancer were included. MAIN OUTCOME MEASURES: The main outcome measures were the incidence of pulmonary metastasis and overall survival. RESULTS: A total of 156 patients (3.2%) were diagnosed with pulmonary metastasis after a median of 16 months from the time of radical surgery for colon cancer to detection of pulmonary metastasis. The pulmonary metastasis incidence rate by the TNM stage was 0.5% in stage I, 1.6% in stage II, and 6% in stage III. Risk factors for pulmonary metastasis were preoperative CEA >5 ng/mL, cancer obstruction, N stage, vascular invasion, perineural invasion, and adjuvant chemotherapy for primary colon cancer in multivariable analysis. LIMITATION: This was a retrospective single-center study. CONCLUSIONS: Preoperative CEA >5 ng/mL, cancer obstruction, pN stage, vascular invasion, perineural invasion, and receiving adjuvant chemotherapy for primary colon cancer were risk factors for pulmonary metastasis in colon cancer. Therefore, patients with risk factors for pulmonary metastasis should be recommended for intensive follow-up to detect lung metastases. See Video Abstract . METSTASIS PULMONAR EN EL PRIMER SITIO TRAS CIRUGA CURATIVA DEL CNCER DE COLON INCIDENCIA Y FACTORES DE RIESGO SEGN ESTADIO TNM: ANTECEDENTES:Los pulmones son uno de los sitios más comunes de metástasis del cáncer de colon. Algunos estudios informaron que aproximadamente entre el 2% y el 10% de los pacientes con cáncer de colon desarrollaron metástasis pulmonar. Sin embargo, entre estos estudios, las características de los pacientes fueron heterogéneas y la información sobre la incidencia de metástasis pulmonares según el estadio TNM fue escasa.OBJETIVO:Este estudio evaluó la incidencia de metástasis pulmonar en cáncer de colon sin metástasis sincrónica tratada con cirugía radical e identificó factores de riesgo para metástasis pulmonar según el estadio TNM.DISEÑO Y AJUSTES:Este estudio retrospectivo incluyó a todos los pacientes con cáncer de colon sin metástasis que se sometieron a cirugía radical por tumor primario en el Samsung Medical Center entre enero de 2007 y diciembre de 2016.PACIENTES:Se incluyó un total de 4.889 pacientes sometidos a cirugía radical por cáncer de colon en estadio I-III.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la incidencia de metástasis pulmonar y la supervivencia general.RESULTADOS:Un total de 156 pacientes (3,2%) fueron diagnosticados con metástasis pulmonar con una duración media de 16 meses desde el momento de la cirugía radical por cáncer de colon hasta la detección de la metástasis pulmonar. La tasa de incidencia de metástasis pulmonares por estadio TNM fue del 0,5% en el estadio I, del 1,6% en el estadio II y del 6% en el estadio III. Los factores de riesgo de metástasis pulmonar fueron CEA preoperatorio superior a 5 ng/ml, obstrucción por cáncer, estadio N, invasión vascular, invasión perineural y quimioterapia adyuvante para el cáncer de colon primario en un análisis multivariable.LIMITACIÓN:Este fue un estudio retrospectivo de un solo centro.CONCLUSIÓN:CEA preoperatorio superior a 5 ng/ml, obstrucción por cáncer, estadio pN, invasión vascular, invasión perineural y recibir quimioterapia adyuvante para el cáncer de colon primario fueron factores de riesgo de metástasis pulmonar en el cáncer de colon. Por lo tanto, se debe recomendar un seguimiento intensivo a los pacientes con factores de riesgo de metástasis pulmonares para detectar metástasis pulmonares. (Traducción-Dr Yolanda Colorado ).

Prognostic Impact of Mucinous Adenocarcinoma in Stage II and III Colon Cancer.

BACKGROUND: Mucinous adenocarcinoma is a rare histologic feature of colorectal cancer and is characterized by oncologic features that are different from those of adenocarcinoma. However, there are conflicting views regarding the prognostic impact of mucinous adenocarcinoma on colon cancer. OBJECTIVE: This study aimed to evaluate the prognostic impact of mucinous adenocarcinoma in stage II and III colon cancer. DESIGN: This was a retrospective cohort study. SETTINGS: This study was conducted between January 2010 and December 2015. Patients were divided into the mucinous adenocarcinoma and nonmucinous adenocarcinoma groups. Disease-free survival and overall survival were assessed using propensity score matching. PATIENTS: Overall, 2532 patients who underwent radical surgery for stage II and III colon cancer were included in the study. MAIN OUTCOME MEASURES: The main outcome measures were disease-free survival and overall survival. RESULTS: The median follow-up duration was 86 months. The disease-free survival and overall survival were significantly lower in the mucinous adenocarcinoma group than in the nonmucinous adenocarcinoma group. In subgroup analysis, there was no significant difference in the disease-free survival and overall survival between patients with and without mucinous adenocarcinoma with stage II colon cancer. In stage III colon cancer, the disease-free survival and overall survival were significantly lower in patients with mucinous adenocarcinoma than in those without mucinous adenocarcinoma. Multivariable analysis showed that mucinous adenocarcinoma was a poor prognostic factor for disease-free survival and overall survival. LIMITATION: The study's limitations include those that are inherently associated with retrospective single-center studies. CONCLUSIONS: Mucinous adenocarcinoma is a poor prognostic factor in stage III but not in stage II colon cancer. Therefore, mucinous adenocarcinoma might not be regarded as an independent risk factor requiring chemotherapy for favorable oncologic outcomes. However, for stage III colon cancer, patients with mucinous adenocarcinoma require close observation. IMPACTO PRONSTICO DEL ADENOCARCINOMA MUCINOSO EN LAS ETAPAS II Y III DE CNCER DE CLON: ANTECEDENTES:El adenocarcinoma mucinoso es una característica histológica rara del cáncer colorrectal, se caracteriza por propiedades oncológicas que son diferentes a las del adenocarcinoma. Sin embargo, existen puntos de vista contradictorios con respecto al impacto pronóstico del adenocarcinoma mucinoso en el cáncer de colon.OBJETIVO:Este estudio tuvo como objetivo evaluar el impacto pronóstico del adenocarcinoma mucinoso en las etapas II y III de cáncer de cólon.DISEÑO Y CONFIGURACIONES:Este estudio de cohorte retrospectivo se realizó entre enero de 2010 y diciembre de 2015. Los pacientes se dividieron entre grupos de adenocarcinoma mucinoso y adenocarcinoma no mucinoso. La supervivencia libre de enfermedad y la supervivencia global se evaluaron utilizando emparejamiento por puntuación de propensión.PACIENTES:En general, 2,532 pacientes que se sometieron a cirugía radical para etapa II y III de cáncer de colon se incluyeron en el estudio.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la supervivencia libre de enfermedad y la supervivencia general.RESULTADOS:La mediana de duración del seguimiento fue de 86 meses. La supervivencia libre de enfermedad y la supervivencia global fueron significativamente menores en el grupo de adenocarcinoma mucinoso que en el grupo de adenocarcinoma no mucinoso. En el análisis de subgrupos, no hubo diferencias significativas en la supervivencia libre de enfermedad y la supervivencia global entre los pacientes con o sin adenocarcinoma mucinoso con cáncer de cólon etapa II. En el cáncer de colon etapa III, la supervivencia libre de enfermedad y la supervivencia global fueron significativamente más bajas en pacientes con adenocarcinoma mucinoso que en aquellos sin adenocarcinoma mucinoso. El análisis multivariable mostró que el adenocarcinoma mucinoso era un factor de mal pronóstico para la supervivencia libre de enfermedad y la supervivencia global.LIMITACIONES:Las limitaciones del estudio incluyen aquellas que están inherentemente asociadas con estudios retrospectivos de un solo centro.CONCLUSIONES:El adenocarcinoma mucinoso es un factor de mal pronóstico en el cáncer de colon etapa III pero no en etapa II. Por lo tanto, el adenocarcinoma mucinoso podría no considerarse un factor de riesgo independiente que requiera quimioterapia para obtener resultados oncológicos favorables. Sin embargo, para el cáncer de colon etapa III, los pacientes con adenocarcinoma mucinoso requieren observación cercana. (Traducción-Dr. Aurian Garcia Gonzalez ).

Emergency gastrointestinal tract operation associated with cytomegalovirus infection.

Purpose: Cytomegalovirus (CMV) infection is common in immunocompromised patients. Enterocolitis caused by CMV infection can lead to perforation and bleeding of the gastrointestinal (GI) tract, which requires emergency operation. We investigated the demographics and outcomes of patients who underwent emergency operation for CMV infection of the GI tract. Methods: This retrospective study was conducted between January 2010 and December 2020. Patients who underwent emergency GI operation and were diagnosed with CMV infection through a pathologic examination of the surgical specimen were included. The diagnosis was confirmed using immunohistochemical staining and evaluated by experienced pathologists. Results: A total of 27 patients who underwent operation for CMV infection were included, 18 of whom were male with a median age of 63 years. Twenty-two patients were in an immunocompromised state. Colon (37.0%) and small bowel (37.0%) were the most infected organs. CMV antigenemia testing was performed in 19 patients; 13 of whom showed positive results. The time to diagnose CMV infection from operation and time to start ganciclovir treatment were median of 9 days. The reoperation rate was 22.2% and perforation was the most common cause of reoperation. In-hospital mortality rate was 25.9%. Conclusion: CMV infection in the GI tract causes severe effects, such as hemorrhage or perforation, in immunocompromised patients. When these outcomes are observed in immunocompromised patients, suspicion of CMV infection and further evaluation for CMV detection in tissue specimens is required for proper treatment.

Prognostic Impact of Lymphatic Invasion, Venous Invasion, Perineural Invasion, and Tumor Budding in Rectal Cancer Treated With Neoadjuvant Chemoradiotherapy Followed by Total Mesorectal Excision.

BACKGROUND: The diagnostic implications of lymphatic invasion, venous invasion, perineural invasion, and tumor budding in rectal cancer treated with neoadjuvant chemoradiotherapy are unknown. OBJECTIVE: This study aimed to identify the prognostic impact of lymphatic invasion, venous invasion, perineural invasion, and tumor budding in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy. DESIGN: This was a retrospective cohort study. SETTINGS: This study was conducted at the Samsung Medical Center. Grouping was performed on the basis of lymphatic invasion, venous invasion, perineural invasion, and tumor budding status: no-risk group with 0 factor (n = 299), low-risk group with any 1 factor (n = 131), intermediate-risk group with any 2 factors (n = 75), and high-risk group with 3 or 4 risk factors (n = 32). PATIENTS: Patients who underwent neoadjuvant chemoradiotherapy, followed by radical operation for locally advanced rectal cancer, from January 2010 to December 2015 were included. MAIN OUTCOME MEASURES: The main outcome measures were disease-free and overall survival. RESULTS: Disease-free and overall survival varied significantly between the groups in stage III ( p < 0.001 and p < 0.001). Disease-free survival in stage I differed between the no-risk group and the intermediate-risk group ( p = 0.026). In stage II, disease-free and overall survival differed between the no-risk group and the intermediate-risk group ( p = 0.010 and p = 0.045). In multivariable analysis, risk grouping was an independent prognostic factor for both disease-free (p <0.001) and overall survival ( p < 0.001). LIMITATIONS: The inherent limitations are associated with the retrospective single-center study design. CONCLUSIONS: Lymphatic invasion, venous invasion, perineural invasion, and tumor budding are strong prognostic factors for disease-free and overall survival in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy. Therefore, adjuvant chemotherapy is strongly recommended in patients with positive lymphatic invasion, venous invasion, perineural invasion, and tumor budding. See Video Abstract at http://links.lww.com/DCR/B919 . IMPACTO PRONSTICO DE LA INVASIN LINFTICA, LA INVASIN VENOSA, LA INVASIN PERINEURAL Y LA GEMACIN TUMORAL EN EL CNCER DE RECTO TRATADO CON QUIMIORRADIOTERAPIA NEOADYUVANTE SEGUIDA DE ESCISIN TOTAL DEL MESORRECTO: ANTECEDENTES:Se desconocen las implicaciones diagnósticas de la invasión linfática, la invasión venosa, la invasión perineural y el crecimiento tumoral en el cáncer de recto tratado con quimiorradioterapia neoadyuvante.OBJETIVO:Este estudio fue diseñado para identificar el impacto pronóstico de la invasión linfática, la invasión venosa, la invasión perineural y la gemación tumoral en el cáncer de recto localmente avanzado tratado con quimiorradioterapia neoadyuvante.DISEÑO:Este estudio fue un estudio de cohorte retrospectivo.AJUSTES:Este estudio se realizó en el Centro Médico Samsung. La agrupación se realizó en función de la invasión linfática, la invasión venosa, la invasión perineural y el estado de crecimiento del tumor: grupo sin riesgo con 0 factores (n = 299), grupo de bajo riesgo con cualquier factor 1 (n = 131), grupo de riesgo intermedio con 2 factores cualquiera (n = 75), y un grupo de alto riesgo con 3 o 4 factores de riesgo (n = 32).PACIENTES:Se incluyeron un total de 537 pacientes que se sometieron a quimiorradioterapia neoadyuvante seguida de operación radical por cáncer de recto localmente avanzado desde enero de 2010 hasta diciembre de 2015.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la supervivencia libre de enfermedad y la supervivencia general.RESULTADOS:La mediana del período de seguimiento fue de 77 meses, y la supervivencia libre de enfermedad a los 5 años y la supervivencia general a los 5 años variaron significativamente entre los grupos en el estadio III (p < 0,001, p < 0,001). La supervivencia libre de enfermedad a los 5 años en el estadio I difirió entre el grupo sin riesgo y el grupo de riesgo intermedio (p = 0,026). En el estadio II, la supervivencia libre de enfermedad a 5 años y la supervivencia global a 5 años difirieron entre el grupo sin riesgo y el grupo de riesgo intermedio p = 0,010, p = 0,045). En el análisis multivariable, la agrupación de riesgo fue un factor pronóstico independiente tanto para la supervivencia libre de enfermedad (p < 0,001) como para la supervivencia global (p < 0,001).LIMITACIÓN:Las limitaciones inherentes están asociadas con el diseño de estudio retrospectivo de un solo centro..CONCLUSIÓN:La invasión linfática, la invasión venosa, la invasión perineural y la gemación tumoral son fuertes factores pronósticos para la supervivencia libre de enfermedad y la supervivencia general en el cáncer de recto localmente avanzado tratado con quimiorradioterapia neoadyuvante. Por lo tanto, se recomienda fuertemente la quimioterapia adyuvante en pacientes con invasión linfática positiva, invasión venosa, invasión perineural y tumor en en formacion. Consulte Video Resumen en http://links.lww.com/DCR/B919 . (Traducción-Dr Yolanda Colorado ).

Bevacizumab increases the risk of anastomosis site leakage in metastatic colorectal cancer.

Background: Bevacizumab is a humanized monoclonal antibody against vascular endothelial growth factor and is used in combination with first-line chemotherapy in the treatment of metastatic colorectal cancer. One of the side effects of bevacizumab is gastrointestinal perforation. This study was designed to identify the effect of bevacizumab in intestinal anastomosis site healing. Methods: From January 2010 to December 2020, patients diagnosed with stage IV colorectal cancer treated with palliative chemotherapy or chemoradiotherapy followed by radical surgery were retrospectively reviewed. Clinical signs or symptoms and computed tomography were tools used for diagnosing anastomosis site leakage. The patients were divided into two groups, the bevacizumab group (n = 136) and the non-bevacizumab group (n = 124). Results: Among the 260 patients 14 (5.4%) patients were diagnosed with anastomosis site leakage. In the bevacizumab group, 13 (9.6%) patients were diagnosed with anastomotic leakage. In the non-bevacizumab group, 1 (0.8%) patient was diagnosed with anastomotic leakage. Anastomosis site leakage was significantly higher in the bevacizumab treatment group (P < 0.001). In the bevacizumab group, period of drug discontinuation before surgery was factor associated with anastomosis site leakage in multivariable analysis (P = 0.031). Conclusion: Stage IV colorectal patients treated with bevacizumab before radical surgery for primary cancer should be carefully observed of anastomosis site leakage after surgery, and the period of drug discontinuation before surgery should be longer than 5 weeks to avoid anastomosis site leakage.

Correlation between T stage and lymph node metastasis in rectal cancer treated with preoperative chemoradiotherapy.

Background: Depth of tumor is a risk factor for lymph node metastasis in rectal cancer, but impact of yield pathologic T (ypT) stage on lymph node involvement in rectal cancer remains unclear. The aim of this study was to evaluate the correlation between ypT stage and lymph node metastasis. Methods: From January 2010 to December 2015, 602 patients who were diagnosed with rectal cancer and treated with neoadjuvant chemoradiotherapy (CRT) followed by radical operation were reviewed retrospectively. The correlations between ypT stage and lymph node status and survival were evaluated. Results: On pathology, 179 (29.7%) patients exhibited regional lymph node metastasis. Lymph node metastasis was seen in 8.5% of ypT0 patients, 20% of ypT1, 18.4% of ypT2, 47.5% of ypT3, and 27.3% of ypT4. Positive lymph node metastasis was correlated with ypT stage. In addition, the difference of lymph node metastasis in ypT stage subgroups was statistically significant (p < 0.001). Five-year disease-free survival was significantly different in the ypT stage subgroups (88.7% versus 86.7% versus 82.6% versus 64.7% versus 72.7%, p < 0.001), as was 5-year overall survival (96.2% versus 90.0% versus 95.8% versus 80.0% versus 90.9%, p < 0.001). Conclusion: YpT stage is associated with lymph node metastasis in rectal cancer treated with neoadjuvant CRT and radical operation, and ypT0 patients exhibited an 8.5% lymph node metastasis rate. Therefore, the decision for local excision or the watch-and-wait strategy for rectal cancer treated with neoadjuvant CRT and predicted to show a pathologic complete response should be considered with caution.

Can CCRT/RT Achieve Favorable Oncologic Outcome in Rectal Cancer Patients With High Risk Feature After Local Excision?

Purpose: The oncologic outcome of concurrent chemoradiotherapy (CCRT) after local excision in patients with high-risk early rectal cancer as compared with radical operation has not been reported. The aim of this study is to compare the oncologic outcome between radical operation and adjuvant CCRT after local excision for high-risk early rectal cancer. Materials and Methods: From January 2005 to December 2015, 266 patients diagnosed with early rectal cancer and treated with local excision who showed high-risk characteristics were retrospectively analyzed. Propensity score matching was applied in a ratio of 1:4, comparing the CCRT/radiotherapy (RT) (n = 34) and radical operation (n = 91) groups. Univariate and multivariate analyses were performed to identify prognostic factors for survival. Results: The median follow-up period was 112 months. The 5-year disease-free survival rate and the 5-year overall survival of the radical operation group were significantly higher than those of the CCRT/RT group after propensity score matching (96.7% vs. 70.6%, p <0.001; 100% vs. 91.2%, p = 0.005, respectively). In a multivariate analysis, salvage therapy type and preoperative carcinoembryonic antigen (CEA) were prognostic factors for 5-year disease-free survival (p <0.001 and p = 0.021, respectively). The type of salvage therapy, the preoperative CEA, and the pT were prognostic factors for 5-year overall survival (p = 0.009, p = 0.024, and p = 0.046, respectively). Conclusions: Patients who undergo radical operations after local excision with a high-risk early rectal cancer had better survival than those treated with adjuvant CCRT/RT. Therefore, radical surgery may be recommended to high-risk early rectal cancer patients who have undergone local excision for more favorable oncologic outcomes.

Oncologic outcomes of pathologic T4 and T3 colon cancer patients diagnosed with clinical T4 stage disease using preoperative computed tomography scan.

BACKGROUND: The diagnostic accuracy of computed tomography (CT) for colon cancer is low, and the preoperative risk factors for locally advanced colon cancer are unknown. This study aimed to evaluate the correlation between preoperative CT scan findings and oncologic outcomes and to identify risk factors associated with locally advanced colon cancer. MATERIALS AND METHODS: Patients diagnosed with clinical stage (cT) 4 colon cancer based on preoperative CT scan findings who underwent curative surgery between January 2005 and December 2015 were retrospectively studied. Patients were divided according to pathologic stage (pT) into pT3 (n = 114) and pT4 (n = 102). RESULTS: The disease-free survival rate was significantly different between the pT3 and pT4 groups (88.6% vs. 68.6%, p < 0.001). The overall survival rate of the pT3 group was significantly higher than that of the pT4 group (91.2% vs. 76.5%, p = 0.002). Perineural invasion and tumor budding were identified as preoperative risk factors predisposing to pT4 staging (p = 0.044, p = 0.001). CONCLUSION: The survival rate of pT3 patients was significantly higher than that of pT4 patients with a preoperative cT4 diagnosis. This suggests that when planning for neoadjuvant chemotherapy in locally advanced colon cancer, preoperative CT scan findings may overestimate clinical staging and lead to inappropriate treatment. Thus, there is a need for a new modality to evaluate local advancement in colon cancer.

Correction to: Lymphovascular invasion, perineural invasion, and tumor budding are prognostic factors for stage I colon cancer recurrence.

The name of the author of the original published version of this article was presented incorrectly. The author name "JungWook Huh" should have been presented as "Jung Wook Huh".

Lymphovascular invasion, perineural invasion, and tumor budding are prognostic factors for stage I colon cancer recurrence.

BACKGROUND: The diagnostic impact of lymphovascular invasion (LVI), perineural invasion (PNI), and tumor budding in stage I colon cancer is currently unknown. This study was conducted to evaluate the prognostic impact of LVI, PNI, and tumor budding in stage I colon cancer. METHODS: From January 2008 to December 2013, 720 patients who underwent curative surgery and were diagnosed with stage I colon cancer were reviewed retrospectively. These patients were categorized into two groups based on LVI, PNI, and tumor budding: the no risk group (n = 566) and risk group (n = 154). RESULTS: Median follow-up period was 103.5 months, and the 5-year disease-free survival rate of the risk group was significantly lower than that of the no risk group (p = 0.025). In multivariate analysis, only the risk group had prognostic factors for 5-year disease-free survival (p = 0.036). In addition, only differentiation was an independent predictor in the risk group (p = 0.009). CONCLUSION: LVI, PNI, and tumor budding are strong prognostic factors for stage I colon cancer. Therefore, patients with positive LVI, PNI, or tumor budding should receive close follow-up and potentially be considered for chemotherapy.

Sedation-free colonoscopy using an upper endoscope is tolerable and effective in patients with low body mass index: a prospective randomized study.

OBJECTIVE: Small-caliber upper endoscopes can be used safely and effectively for sedation-free colonoscopy. The objective of the study is to assess the efficacy of a small-caliber upper endoscope (9.2 mm) comparing with a standard colonoscope (12.2 mm). METHODS: In a prospective trial, patients undergoing sedation-free colonoscopy were randomly assigned to the upper endoscope (E) or the standard colonoscope (C). Outcome measures included patient self-assessed pain score (4-point scale), endoscopist-assessed pain score (4-point scale), cecal intubation rate, difficult cecal intubation rate (>900 s), number of polyps detected, and complication rates. RESULTS: A total of 244 patients were entered. Clinical characteristics were not different between the two groups. Cecal intubation was achieved in 91.0% of the patients in each group. The mean patient self-assessed pain score (SD) was significantly lower in the E group compared with the C group: 1.44 (0.81) versus 2.08 (1.10), p < 0.001. The mean endoscopist assessment of patient pain score (SD) was significantly lower in the E group compared with the C group as well: 1.27 (0.67) versus 1.58 (0.90), p= 0.003. In patients with low body mass index (BMI < 22 kg/m(2)), the cecal intubation rate was significantly higher in the E group (97.7%vs 79.4%, p= 0.026) and the difficult cecal intubation rate was significantly lower in the E group (9.3%vs 32.4%, p= 0.011). There were no significant differences in the number of polyps detected and complication rates between the two groups. CONCLUSION: A small-caliber upper endoscope is tolerable and effective for sedation-free colonoscopy, especially in patients with low BMI.

Expression of cyclooxygenase-2, p53 and Ki-67 in gastric cancer.

It has been reported that p53 mutation may contribute to upregulate cyclooxygenase (COX)-2 expression that is observed in malignant tissues. These molecules are involved in carcinogenesis by affecting tumor cell proliferation. The aim of this study was to examine the relationship between COX-2 or p53 expression and clinico-pathological characteristics including tumor cell proliferation in gastric cancer. COX-2 and p53 expressions were investigated with immunostaining, in tissue specimens obtained from 119 patients who underwent surgery for gastric cancer. The Ki-67 labeling index (LI) was counted by Ki-67 immunostaining. COX-2 and p53 expressions correlated significantly with depth of tumor invasion. However, there was no association between COX-2 or p53 expression and survival. p53 expression did not correlate with COX-2 expression. There was no significant difference in various clinicopathological variables between Ki-67 LI subgroups. The mean Ki-67 LI value of COX-2 positive tumors was significantly higher than that of negative tumors. The mean Ki-67 LI value of p53 positive tumors was not significantly higher than that of negative tumors. The mean Ki-67 LI value of both COX-2 and p53 positive tumors was significantly higher than that of both negative tumors. These results imply that COX-2 expression is associated with tumor cell proliferation of gastric cancer.

Antibiotic prophylaxis using third generation cephalosporins can reduce the risk of early rebleeding in the first acute gastroesophageal variceal hemorrhage: a prospective randomized study.

Bacterial infection may be a critical trigger for variceal bleeding. Antibiotic prophylaxis can prevent rebleeding in patients with acute gastroesophageal variceal bleeding (GEVB). The aim of the study was to compare prophylactic third generation cephalosporins with on-demand antibiotics for the prevention of gastroesophageal variceal rebleeding. In a prospective trial, patients with the first acute GEVB were randomly assigned to receive prophylactic antibiotics (intravenous cefotaxime 2 g q 8 hr for 7 days, prophylactic antibiotics group) or to receive the same antibiotics only when infection became evident (on-demand group). Sixty-two patients in the prophylactic group and 58 patients in the on-demand group were included for analysis. Antibiotic prophylaxis decreased infection (3.2% vs. 15.5%, p=0.026). The actuarial rebleeding rate in the prophylactic group was significantly lower than that in the on-demand group (33.9% vs. 62.1%, p=0.004). The difference of rebleeding rate was mostly due to early rebleeding within 6 weeks (4.8% vs. 20.7%, p=0.012). On multivariate analysis, antibiotic prophylaxis (relative hazard: 0.248, 95% confidence interval (CI): 0.067-0.919, p=0.037) and bacterial infection (relative hazard: 3.901, 95% CI: 1.053-14.448, p=0.042) were two independent determinants of early rebleeding. In conclusion, antibiotic prophylaxis using third generation cephalosporins can prevent bacterial infection and early rebleeding in patients with the first acute GEVB.

Expression of survivin in gastric cancer and its relationship with tumor angiogenesis.

BACKGROUND/AIMS: Survivin, a member of inhibitors of apoptosis, has been found in various human cancers. Its expression is associated with tumor progression and adverse outcome. Angiogenesis is an essential process for the primary tumor to grow and invade the adjacent normal structures. Angiogenic factors such as vascular endothelial growth factor induce survivin expression in endothelial cells. The current study was designed to investigate the possible role of survivin and vascular endothelial growth factor status for angiogenesis in human gastric cancer. METHODS: In this study, we conducted an immunohistochemical investigation of survivin and vascular endothelial growth factor expression in 106 tissue samples obtained from gastric cancer patients undergoing surgical treatment. To assess tumor angiogenesis, microvessel density was counted by staining endothelial cells immunohistochemically using anti-CD34 monoclonal antibody. RESULTS: The positive expression of survivin and vascular endothelial growth factor in gastric cancer tissues was demonstrated in 50.0 and 69.8% of cases, respectively. The expression of survivin did not associate with vascular endothelial growth factor expression. Expression of survivin was significantly associated with tumor size, depth of invasion, lymph node metastasis, tumor stage and poor survival (P=0.011, 0.004, 0.020, 0.002, 0.046, respectively). High microvessel density was significantly associated with lymph node metastasis and poor survival (P=0.006 and 0.017, respectively). The mean microvessel density value of survivin positive tumors was 87.4+/-34.4 and significantly higher than that of survivin negative tumors (P=0.016). The mean microvessel density value of vascular endothelial growth factor positive tumors was 98.7+/-37.0 and significantly higher than that of vascular endothelial growth factor negative tumors (P=0.001). A combined analysis of survivin and vascular endothelial growth factor status showed that the mean microvessel density value of both positive tumors was 103.7+/-33.1 and significantly higher than that of both negative tumors (P<0.001). CONCLUSION: These results suggest that survivin may play an important role in carcinogenesis by stimulating tumor angiogenesis in human gastric cancer.

Agenesis of the dorsal pancreas: a case report and review of the literature.

Partial or complete agenesis of the dorsal pancreas is a rare congenital anomaly that results from the embryological failure of the dorsal pancreatic bud to form the body and tail of the pancreas. To date, four cases have been reported in Korea. We report an additional case; a 25-year-old woman presented with diabetes mellitus and abdominal pain. Abdominal computed tomography (CT) revealed a normal-appearing pancreatic head, but the body and tail were not visualized. Endoscopic cholangiopancreatogram (ERCP) revealed a short pancreatic duct in the uncinate process and the head and the duct of Santorini draining into the minor papilla. Abdominal magnetic resonance imaging (MRI) findings were similar to the CT and ERCP results. The patient was diagnosed with partial agenesis of the dorsal pancreas by CT, ERCP and MRI.

Zollinger-Ellison syndrome associated with neurofibromatosis type 1: a case report.

BACKGROUND: Neurofibromatosis type 1 is an autosomal dominant neurocutaneous disorder with characteristic features of skin and central nervous system involvement. Gastrointestinal involvement is rare, but the risk of malignancy development is considerable. Zollinger-Ellison syndrome is caused by gastrin-secreting tumors called gastrinomas. Correct diagnosis is often difficult, and curative treatment can only be achieved surgically. CASE PRESENTATION: A 41-year-old female affected by neurofibromatosis type 1 presented with a history of recurrent epigastric soreness, diarrhea, and relapsing chronic duodenal ulcer. Her serum fasting gastrin level was over 1000 pg/mL. An abdominal CT scan revealed a 3 x 2-cm, well-enhanced mass adjacent to the duodenal loop. She was not associated with multiple endocrine neoplasia type 1. Operative resection was performed and gastrinoma was diagnosed by immunohistochemical staining. The serum gastrin level decreased to 99.1 pg/mL after surgery, and symptoms and endoscopic findings completely resolved without recurrences. CONCLUSION: Gastrinoma is difficult to detect even in the general population, and hence symptoms such as recurrent idiopathic peptic ulcer and diarrhea in neurofibromatosis type 1 patients should be accounted for as possibly contributing to Zollinger-Ellison syndrome.