Clinical Outcomes of Upfront Primary Tumor Resection in Synchronous Unresectable Metastatic Colorectal Cancer.

The role of upfront primary tumor resection (PTR) in patients with unresectable metastatic colorectal cancer without severe symptoms remains controversial. We retrospectively analyzed the role of PTR in overall survival (OS) in this population. Among the 205 patients who enrolled, the PTR group (n = 42) showed better performance (p = 0.061), had higher frequencies of right-sided origin (p = 0.058), the T4 stage (p = 0.003), the M1a stage (p = 0.012), and <2 organ metastases (p = 0.002), and received fewer targeted agents (p = 0.011) than the chemotherapy group (n = 163). The PTR group showed a trend for longer OS (20.5 versus 16.0 months, p = 0.064) but was not related to OS in Cox regression multivariate analysis (p = 0.220). The male sex (p = 0.061), a good performance status (p = 0.078), the T3 stage (p = 0.060), the M1a stage (p = 0.042), <2 organ metastases (p = 0.035), an RAS wild tumor (p = 0.054), and the administration of targeted agents (p = 0.037), especially bevacizumab (p = 0.067), seemed to be related to PTR benefits. Upfront PTR could be considered beneficial in some subgroups, but these findings require larger studies to verify.

Differential Perspectives by Specialty on Oligometastatic Colorectal Cancer: A Korean Oligometastasis Working Group's Comparative Survey Study.

PURPOSE: Despite numerous studies on the optimal treatments for oligometastatic disease (OMD), there is no established interdisciplinary consensus on its diagnosis or classification. This survey-based study aimed to analyze the differential opinions of colorectal surgeons and radiation oncologists regarding the definition and treatment of OMD from the colorectal primary. MATERIALS AND METHODS: A total of 141 participants were included in this study, consisting of 63 radiation oncologists (44.7%) and 78 colorectal surgeons (55.3%). The survey consisted of 19 questions related to OMD, and the responses were analyzed using the chi-square test to determine statistical differences between the specialties. RESULTS: The radiation oncologists chose "bone" more frequently compared to the colorectal surgeons (19.2% vs. 36.5%, p=0.022), while colorectal surgeons favored "peritoneal seeding" (26.9% vs. 9.5%, p=0.009). Regarding the number of metastatic tumors, 48.3% of colorectal surgeons responded that "irrelevant, if all metastatic lesions are amendable to local therapy", while only 21.8% of radiation oncologist chose same answer. When asked about molecular diagnosis, most surgeons (74.8%) said it was important, but only 35.8% of radiation oncologists agreed. CONCLUSION: This study demonstrates that although radiation oncologists and colorectal surgeons agreed on a majority of aspects such as diagnostic imaging, biomarker, systemic therapy, and optimal timing of OMD, they also had quite different perspectives on several aspects of OMD. Understanding these differences is crucial to achieving multidisciplinary consensus on the definition and optimal management of OMD.

Robotic Lateral Pelvic Lymph Node Dissection Could Harvest More Lateral Pelvic Lymph Nodes over Laparoscopic Approach for Mid-to-Low Rectal Cancer: A Multi-Institutional Retrospective Cohort Study.

Lateral pelvic lymph node dissection (LPND) is a technically demanding procedure. This study aimed to compare the short-term outcomes of laparoscopic and robotic LPNDs. This multi-institutional retrospective study included 108 consecutive patients who underwent laparoscopic or robotic total mesorectal excision with LPND for locally advanced rectal cancer. There were 74 patients in the laparoscopic and 34 in the robotic groups. The median operation time was longer in the robotic group than in the laparoscopic group (353 vs. 275 min, p < 0.001). No patients underwent conversion to open surgery in either group. Pathological LPN metastases were observed in 24 and 8 patients in the laparoscopic and robotic groups, respectively (p = 0.347). Although the number of harvested mesorectal lymph nodes was similar (15.5 vs. 15.0, p = 0.968), the number of harvested LPNs was higher in the robotic than in the laparoscopic group (7.0 vs. 5.0, p = 0.004). Postoperative complications and length of hospital stay were similar (robotic vs. laparoscopic, 35.3% and 7 days vs. 37.8% and 7 days, respectively). Both laparoscopic and robotic LPND are safe and feasible for locally advanced rectal cancers, but robotic LPND showed more harvested lateral lymph node than laparoscopic LPND.

Assessment of Colorectal Anastomosis with Intraoperative Colonoscopy: Its Role in Reducing Anastomotic Complications.

The use of intraoperative colonoscopy (IOC) to evaluate the integrity of newly created anastomosis has been advocated by some surgeons. However, whether direct visualization of fresh anastomosis can help reduce anastomotic problems is still unclear. This study investigates the impact of immediate endoscopic assessment of colorectal anastomosis on anastomotic problems. This is a retrospective study conducted at a single center. Among six hundred forty-nine patients who underwent stapled anastomosis for left-sided colorectal cancer, the anastomotic complications were compared between patients who underwent IOC and those who did not. Additionally, patients with subsequent intervention after the IOC were compared to those without the intervention. Twenty-seven patients (5.0%) developed anastomotic leakage, and six (1.1%) experienced anastomotic bleeding postoperatively. Of the patients with IOC, 70 patients received reinforcement sutures to secure anastomotic stability. Of 70 patients, 39 patients showed abnormal findings in IOC. Thirty-seven patients (94.9%) who underwent reinforcement sutures did not develop postoperative anastomotic problems. This study demonstrates that IOC assessment with reinforcement sutures does not imminently reduce the rate of anastomotic complications. However, its use may play a role in detecting early technical failure and preventing postoperative anastomotic complications.

One-year experience of robotic transabdominal preperitoneal approach in a single institute: 2 different surgeons with different levels of experience.

Purpose: The robotic platform, an extension of minimally invasive procedures, is distributed nationwide and readily available. However, its application in inguinal hernia repair seems rare in Korea. This report aims to share our initial experience with robotic inguinal hernia repair. Methods: The patients who underwent robotic inguinal hernia repair by 2 different surgeons with different experiences at a single center were retrospectively analyzed. The surgical procedures were performed on all patients using the Da Vinci Xi robotic platform (Intuitive Surgical Inc). Patient demographics, operation variables, and postoperative outcomes were analyzed. Results: A total of 35 patients underwent robotic inguinal hernia repairs consecutively. The mean age was 55.03 ± 18.20 years. The majority of patients were male. The overall mean operation time was 103.98 ± 47.92 minutes for unilateral hernia surgery and 139.28 ± 46.07 minutes for bilateral surgery. None of the patients experienced intraoperative complications. However, postoperative complications were noticed in 8 patients: 3 with seroma formation, 1 with hematoma, 1 with superficial surgical site infection, and 3 with persistent pain at the operation site. Conclusion: This report demonstrates an early experience of hernia surgery using the robotic platform. The robotic approach for transabdominal preperitoneal hernia repair was completed without any significant intraoperative or postoperative complications. It may be a viable option as a minimally invasive technique. Cost-effectiveness, optimal procedural steps, and indications for the robotic approach remain to be further investigated.

Metastasis-Directed Local Therapy of Hepatic Oligometastasis from Colorectal Cancer and Future Perspective in Radiation Therapy.

Introduction of the concept for oligometastasis led to wide application of metastasis-directed local ablative therapies for metastatic colorectal cancer (CRC). By application of the metastasis-directed local ablative therapies including surgical resection, radiofrequency ablation (RFA), and stereotactic ablative body radiotherapy (SABR), the survival outcomes of patients with metastatic CRC have improved. The liver is the most common distant metastatic site in CRC patients, and recently various metastasis-directed local therapies for hepatic oligometastasis from CRC (HOCRC) are widely used. Surgical resection is the first line of metastatic-directed local therapy for HOCRC, but its eligibility is very limited. Alternatively, RFA can be applied to patients who are ineligible for surgical resection of liver metastasis. However, there are some limitations such as inferior local control (LC) compared with surgical resection and technical feasibility based on location, size, and visibility on ultrasonography of the liver metastasis. Recent advances in radiation therapy technology have led to an increase in the use of SABR for liver tumors. SABR is considered complementary to RFA for patients with HOCRC who are ineligible for RFA. Furthermore, SABR can potentially result in better LC for liver metastases > 2-3 cm compared with RFA. In this article, the previous studies regarding curative metastasis-directed local therapies for HOCRC based on the radiation oncologist's and surgeon's perspective are reviewed and discussed. In addition, future perspectives regarding SABR in the treatment of HOCRC are suggested.

Reappraisal of the Lymphatic Drainage System of the Distal Rectum: Functional Lymphatic Flow into the Presacral Space and Its Clinical Implication in Rectal Cancer Treatment.

Understanding the source and route of pelvic metastasis is essential to developing an optimal strategy for controlling local and systemic diseases of rectal cancer. This study aims to delineate the distribution of lymphatic channels and flow from the distal rectum. In fresh-frozen cadaveric hemipelvis specimens, the ligamentous attachment of the distal rectum to the pelvic floor muscles and the presacral fascia were evaluated. Using indocyanine green (ICG) fluorescence imaging, we simultaneously evaluated the gross anatomy of the lymphatic communication of the distal rectum. We also investigated the lymphatic flow in the pelvic cavity intraoperatively in rectal cancer patients who underwent radical rectal resection with total mesorectal excision (TME). In fresh cadavers, multiple small perforating lymphovascular branches exist in the retrorectal space, posteriorly connecting the mesorectum to the presacral fascia. The lymphatic flow from the distal rectum drains directly into the presacral space through the branches. In patients who underwent TME for rectal cancer, intraoperative ICG fluorescence signals were seen in the pelvic sidewalls and the presacral space. This anatomical study demonstrated that the lymphatic flow from the distal rectum runs directly to the pelvic lateral sidewalls and the presacral space, suggesting a possible route of metastasis in distal rectal cancer.

Lateral Lymph Node Size and Tumor Distance From Anal Verge Accurately Predict Positive Lateral Pelvic Lymph Nodes in Rectal Cancer: A Multi-Institutional Retrospective Cohort Study.

BACKGROUND: Lateral pelvic lymph node dissection improves oncological outcomes in rectal cancer patients with suspected lateral pelvic lymph node metastasis. However, the indication for this procedure remains unclear. OBJECTIVE: This study aimed to identify the predictive factors for lateral lymph node metastasis and the indications for lateral pelvic lymph node dissection. DESIGN: A multi-institutional retrospective study. SETTINGS: This study was conducted at 3 university hospitals. PATIENTS: This study involved 105 patients with locally advanced mid/low rectal cancer and clinically suspected lateral pelvic lymph node metastasis who underwent total mesorectal excision with lateral pelvic lymph node dissection between 2015 and 2020. MAIN OUTCOME MEASURES: Indications were set using lateral pelvic lymph node metastasis-associated preoperative factors. RESULTS: Among 105 patients, 36 (34.3%) had pathologically confirmed lateral pelvic lymph node metastasis and 77 (73.3%) underwent preoperative chemoradiation. Tumors located within 5 cm distance from the anal verge ( p = 0.02) and initial node size ≥ 6 mm ( p = 0.001) were significant predictors of lateral pelvic lymph node metastasis. The sensitivity was 100% (36/36) with a cutoff of 6 mm for the initial node size and 94.4% (34/36) with a cutoff of 8 mm for the initial node size. When using initial node size cutoffs of 8 mm for anal verge-to-tumor distance of >5 cm and 6 mm for anal verge-to-tumor distance of ≤5 cm, the sensitivity of lateral pelvic lymph node metastasis was found to be 100%. LIMITATIONS: The retrospective design and small sample size were the limitations of this study. CONCLUSION: Initial node size and tumor height were significant predictors of lateral pelvic lymph node metastasis. This study proposed that an initial node size of ≥8 mm with an anal verge-to-tumor distance of >5 cm and ≥6 mm with an anal verge-to-tumor distance of ≤5 cm are optimal indications for lateral pelvic lymph node dissection in rectal cancer. See Video Abstract at http://links.lww.com/DCR/C101 . EL TAMAO DEL GANGLIO LINFTICO LATERAL Y LA DISTANCIA DEL TUMOR DESDE EL BORDE ANAL PREDICEN CON PRECISIN LOS GANGLIOS LINFTICOS PLVICOS LATERALES POSITIVOS EN EL CNCER DE RECTO UN ESTUDIO DE COHORTE RETROSPECTIVO MULTIINSTITUCIONAL: ANTECEDENTES:La disección de los ganglios linfáticos pélvicos laterales mejora los resultados oncológicos en pacientes con cáncer de recto con sospecha de metástasis en los ganglios linfáticos pélvicos laterales. Sin embargo, la indicación de este procedimiento sigue sin estar clara.OBJETIVO:Nuestro objetivo fue identificar los factores predictivos de la metástasis de los ganglios linfáticos laterales y las indicaciones para la disección de los ganglios linfáticos pélvicos laterales.DISEÑO:Estudio retrospectivo multiinstitucional.AJUSTES:Este estudio se realizó en tres hospitales universitarios.PACIENTES:Este estudio involucró a 105 pacientes con cáncer de recto medio/bajo localmente avanzado y sospecha clínica de metástasis en los ganglios linfáticos pélvicos laterales que se sometieron a una escisión mesorrectal total con disección de los ganglios linfáticos pélvicos laterales entre 2015 y 2020.PRINCIPALES MEDIDAS DE RESULTADO:Las indicaciones se establecieron utilizando los factores preoperatorios asociados con la metástasis de los ganglios linfáticos pélvicos laterales.RESULTADOS:Entre 105 pacientes, 36 (34,3%) tenían metástasis en los ganglios linfáticos pélvicos laterales confirmada patológicamente y 77 (73,3%) se sometieron a quimiorradiación preoperatoria. Los tumores ubicados dentro de los 5 cm desde el borde anal ( p = 0,02) y el tamaño inicial del ganglio ( p = 0,001) fueron predictores significativos de metástasis en los ganglios linfáticos pélvicos laterales. La sensibilidad fue del 100 % (36/36), con un punto de corte de 6 mm para el tamaño inicial del ganglio, seguido de 8 mm para el tamaño inicial del ganglio (94,4%, 34/36). Cuando se utilizó un tamaño de corte inicial del ganglio de 8 mm para una distancia entre el borde anal y el tumor >5 cm y 6 mm para una distancia entre el borde anal y el tumor ≤5 cm, la sensibilidad de la metástasis en los ganglios linfáticos pélvicos laterales fue del 100 %.LIMITACIONES:El diseño retrospectivo y el pequeño tamaño de la muestra.CONCLUSIONES:El tamaño inicial del ganglio y la altura del tumor fueron predictores significativos de metástasis en los ganglios linfáticos pélvicos laterales. Este estudio propuso que un tamaño de ganglio inicial de ≥8 mm con un tumor a >5 cm del margen anal y ≥6 mm con un tumor a ≤5 cm del margen anal son indicaciones óptimas para la disección de los ganglios linfáticos pélvicos laterales en el cáncer de recto. Consulte Video Resumen en http://links.lww.com/DCR/C101 . (Traducción-Dr. Yolanda Colorado ).

The pattern of bowel dysfunction in patients with rectal cancer following the multimodal treatment: anorectal manometric measurements at before and after chemoradiation therapy, and postoperative 1 year.

PURPOSE: Bowel dysfunction commonly occurs in patients with locally advanced rectal cancer treated with a multimodal approach of chemoradiation therapy (CRT) combined with sphincter-preserving rectal resection. This study investigated the decline in anorectal function using sequential anorectal manometric measurements obtained before and after the multimodal treatment as well as at a 1-year follow-up. METHODS: This was a retrospective cohort study conducted in a single center. The study population consisted of patients with locally advanced mid- to low rectal cancer who received the preoperative CRT followed by sphincter-preserving surgery from 2012 to 2016. The anorectal manometric value measured after each treatment modality was compared to demonstrate the degree of decline in anorectal function. A generalized linear model of repeated measures was performed using the manometric values measured pre- and post-CRT, and at 12 months postoperatively. RESULTS: Overall, 100 patients with 3 consecutive manometric data were included in the final analysis. In the overall cohort study, the mean resting and maximal squeezing pressures showed insignificant decrement post-neoadjuvant CRT. At a 1-year postoperative follow-up, the maximal squeezing pressure significantly decreased. The maximal rectal sensory threshold demonstrated significant reduction consecutively after each following treatment (P<0.001). CONCLUSION: The short-term effect of neoadjuvant CRT on the anal sphincters was relatively trivial. The following sphincter-saving surgery resulted in a profound disruption of the anorectal function. Patients with rectal cancer should be consulted on the consequence of multimodal treatment.

Survival Outcomes after Elective or Emergency Surgery for Synchronous Stage IV Colorectal Cancer.

Patients with stage IV colorectal cancer (CRC) who have not undergone primary tumor resection (PTR) are at risk of sudden medical emergencies. Despite the ongoing controversy over the necessity and timing of PTR in patients with stage IV CRC, studies comparing the survival outcomes of elective and emergency surgery in this population are scarce. This is a retrospective study conducted at a single institute. The patients were divided into two groups: the elective surgery (ELS) group (n = 46) and the emergency surgery (EMS) group (n = 26). The primary outcome was 2-year overall survival (OS). During a median follow-up period of 27.0 months, the 2-year OS was significantly better in the ELS group (80% vs. 42.9%, p = 0.002). No significant differences were observed in the 2-year relapse-free survival and 30-day postoperative complication rates. Planning and performing elective surgery could help increase the survival rate of patients with synchronous stage IV CRC, especially those that undergo simultaneous or staged metastasectomy.

Short- and long-term outcomes of local excision with adjuvant radiotherapy in high-risk T1 rectal cancer patients.

PURPOSE: The standard of care for early rectal cancer is radical surgery; however, it carries high postoperative morbidity. This study aimed to assess the short-term and oncological outcomes of local excision and adjuvant radiotherapy in patients with high-risk pathological stage (p) T1 rectal cancer. METHODS: Fifty-five patients underwent local excision with adjuvant radiotherapy or radical resection for high-risk T1 rectal cancer. Patients with adenocarcinoma within 10 cm from the anal verge; pT1 with high-risk features (grade 3-4); a tumor size of ≥3 cm; a positive margin; a lymphovascular or perineural invasion; or a submucosal invasion depth of ≥SM2 were included. RESULTS: The rates of postoperative complications and stoma formation were higher in the radical surgery group (P = 0.021 and P = 0.003, respectively). No significant differences were observed in the overall survival and disease-free survival (DFS) between the 2 groups (P = 0.301 and P = 0.076, respectively). Vascular invasion was a significantly poor prognostic factor for DFS (P = 0.033). The presence of 3 or more high-risk features was associated with a poor DFS (P = 0.002). CONCLUSION: Local excision with adjuvant radiotherapy significantly reduces the risk of complications and stoma formation. It is also an alternative option for patients with fewer than 3 high-risk features.

Is Laparoscopic Complete Mesocolic Excision and Central Vascular Ligation Really Necessary for All Patients With Right-Sided Colon Cancer?

Colon cancer treatment is on the way to evolution over several decades. The minimally invasive surgery has improved postoperative short-term outcomes. Adjuvant chemotherapy has prolonged the survival of advanced colon cancer patients. Hohenberger proposed the noble concept of complete mesocolic excision (CME) which consists of 3 components: plane surgery, sufficient longitudinal bowel resection, and central vascular ligation (CVL). Mesocolic plane surgery shares the same surgical principle of total mesorectal excision, which is maintaining the intact mesothelial envelope. However, there remain debates about the extent of bowel resection and the level of CVL for maximizing lymph node dissection. There is no solid clinical evidence for the oncological necessity and benefit of extended radical dissection in right hemicolectomy. CME with CVL based on open surgery has been adopted in laparoscopic surgery. So, it is also necessary to look at how the CME could be transformed and successfully implanted in the laparoscopic era. Recent rapid advances in surgical technology and cancer biology are preparing for fundamental changes in cancer surgery. In this study, we reviewed the history, oncological necessity, and compatibility of CME for the right hemicolectomy in the laparoscopic era and outline the new perspectives on the evolution of cancer surgery.

The Safety and Feasibility of Laparoscopic Surgery for Very Low Rectal Cancer: A Retrospective Analysis Based on a Single Center's Experience.

In this work we intend to validate the long-term oncologic outcomes for very low rectal cancer over the past 20 years and to determine whether laparoscopic procedures are useful options for very low rectal cancer. A total of 327 patients, who electively underwent laparoscopic rectal cancer surgery for a lesion within 5 cm from the anal verge, were enrolled in this study and their long-term outcomes were reviewed retrospectively. Of 327 patients, 70 patients underwent laparoscopic low anterior resection (LAR), 164 underwent laparoscopic abdominal transanal proctosigmoidocolectomy with coloanal anastomosis (LATA), and 93 underwent laparoscopic abdominoperineal resection (APR). The conversion rate was 1.22% (4/327). The overall postoperative morbidity rate was 26.30% (86/327). The 5-year disease free survival (DFS), 5-year overall survival (OS), and 3-year local recurrence (LR) were 64.3%, 79.7%, and 9.2%, respectively. The CRM involvement was a significant independent factor for DFS (p = 0.018) and OS (p = 0.042) in multivariate analysis. Laparoscopic APR showed poorer 5-year DFS (47.8%), 5-year OS (64.0%), and 3-year LR (17.6%) than laparoscopic LAR (74.1%, 86.4%, 1.9%) and laparoscopic LATA (69.2%, 83.6%, 9.2%). Laparoscopic procedures for very low rectal cancer including LAR, LATA, and APR could be good surgical options in selective patients with very low rectal cancer.

Short- and long-term outcomes of laparoscopic segmental left colectomy for splenic flexure colon cancer: comparison with propensity score matching.

PURPOSE: Splenic flexure colon cancer (SFCC) is a rare disease that accounts for 2%-8% of colorectal cancers, and the extent of surgery and resection is still debatable. There have also been few studies on the safety and feasibility of laparoscopic surgery for SFCC. The purpose of this study is to evaluate outcomes and prognoses of surgery for SFCC. METHODS: We included patients with stage 1 to 3 who had undergone laparoscopic surgery for distal transverse-to-sigmoid colon cancer at 2 hospitals from March 2004 to December 2016 and collected data by retrospective design. We defined SFCC as being cancer between distal transverse and proximal descending colon. The short- and long-term outcomes of the anterior resection (AR) group (those patients who had undergone laparoscopic AR for mid and distal descending to sigmoid colon cancer) and the left colon resection (LR) group (those who had undergone laparoscopic segmental left colectomy for SFCC) were compared using propensity score matching. RESULTS: The median follow-up period was 60 months. The numbers of subjects in the AR and the LR groups were 948 and 118. After 2:1 propensity score matching, 236 vs. 118 patients were selected. There was no significant difference in 5-year disease-free survival (80.7% vs. 78.6%, P = 0.607), and both the 5-year overall survival (89.2% vs. 88.2%, P = 0.563) as well as short-term outcomes showed no statistical difference in most of the variables. CONCLUSION: Laparoscopic segmental left colectomy can be one option among the standard procedures for SFCC.

Effect of Biofeedback Therapy during Temporary Stoma Period in Rectal Cancer Patients: A Prospective Randomized Trial.

BACKGROUND: This prospective randomized controlled study was designed to evaluate the effect of biofeedback therapy (BFT) during temporary stoma period to prevent defecation dysfunction after sphincter-preserving surgery (SPS). METHODS: Following SPS with temporary stoma, patients were divided according to whether (BFT group) or not (Control group) they received BFT. BFT was performed once or twice a week during the temporary stoma period. Kegel exercise were advised to all the patients. Subjective defecation symptoms were evaluated according to Cleveland Clinic Incontinence Score (CCIS) as primary outcome at 12 months postoperatively. Manometric data of five time-points were also analyzed. RESULTS: Twenty-one patients in the BFT group and 23 patients in the control group received anorectal physiologic testing. The incidence of CCIS of more than 9 points, which is the primary end point in this study, was not statistically different between BFT group and control group (p = 1.000). The liquid stool incontinence in the BFT group showed a better tendency (p = 0.06) at 12 months post-SPS. Time-dependent serial changes in maximal sensory threshold (Max RST) was significantly different between the BFT and control groups (p = 0.048). Also, the change of mean resting pressure (MRP) tended to be more stable in the BFT group (p = 0.074). CONCLUSIONS: The BFT in the period of temporary stoma may be related to liquid stool incontinence at 12 months post-SPS and lead to stable MRP and better Max RST. Therefore, BFT during temporary stoma might be helpful for preventing and minimizing defecation dysfunction in high risk patients after SPS, NCT01661829).

Addition of V-Stage to Conventional TNM Staging to Create the TNVM Staging System for Accurate Prediction of Prognosis in Colon Cancer: A Multi-Institutional Retrospective Cohort Study.

We evaluated the prognostic impact of vascular invasion (VI) compared with nodal (N) stage and developed a new staging system including VI in colon cancer. Patients who underwent curative resection with stage II-III colon cancer were assigned to VI and non-VI groups; the latter was subclassified as N0, N1, and N2; a new TNVM staging was devised by adding the V-stage. Among the 2243 study participants, the VI group independently showed worse oncological outcomes than the N1 group (disease-free survival (DFS), hazard-ratio (HR) 1.704, 1.267-2.291; overall survival (OS), HR 2.301, 1.582-3.348). The 5-year DFS in the VI group was 63.4% [N1b (74.6%), p = 0.003; N2a (69.7%), p = 0.126; and N2b (56.8%), p = 0.276], and the 5-year OS was 76.6% [N1b (84.9%), p = 0.004; N2a (83.0%), p = 0.047; and N2b (76.1%), p = 0.906]. Thus, we considered VI as N2a in TNVM staging; 78 patients (3.5%) underwent upstaging. The 5-year OS rates of stage IIB and IIC increased from 88.6% and 65.9% in TNM staging to 90.5% and 85.7% in TNVM staging, respectively. In stage II-III colon cancer, VI had a similar prognostic impact as the N2 stage without VI. The incorporation of the V-stage into the conventional TNM staging facilitates better prediction of prognosis.

Which prognostic factors are important for long-term outcomes in symptomatic obstructive colon cancer? A multi-institutional retrospective cohort study.

Purpose: The prognostic factors in obstructive colon cancer have not been clearly identified. We aimed to identify the prognostic factor to establish optimal treatment strategy in obstructive colon cancer. Methods: Patients who underwent surgery for primary colon cancer in stages II and III with symptomatic obstruction from 2004 to 2010 in six hospitals were retrospectively collected. Clinicopathological and surgical outcomes were compared between stent insertion and emergent surgery group. Multiple regression analysis and survival curve analysis were used to identify the prognostic factors in symptomatic obstructive colon cancer. Results: Among 210 patients, 168 patients (80.0%) underwent stent insertion followed by surgery and 42 patients (20.0%) underwent emergent surgery. Laparoscopic approach (55.4% vs. 23.8%, p < 0.001) and adequate lymph node (LN) harvest (≥12) (93.5% vs. 69.0%, p < 0.001) were significantly higher in stent insertion group. In multiple regression analysis, emergent surgery (hazard ratio [HR], 2.153; 95% confidence interval [CI], 1.031-4.495), vascular invasion (HR, 6.257; 95% CI, 2.784-14.061), and omitting adjuvant chemotherapy (HR, 3.107; 95% CI, 1.394-6.925) were independent poor prognostic factors in 5-year overall survival, and N stage (N1 HR, 3.095; 95% CI, 1.316-7.284; N2 HR, 4.156; 95% CI, 1.671-10.333) was the only poor prognostic factor in 5-year disease-free survival. Conclusion: In symptomatic obstructive colon cancer, emergent surgery, N stage, vascular invasion, and omission of adjuvant chemotherapy were independent poor prognostic factors. Stent insertion is suggested as the initial treatment for symptomatic obstructive colon cancer, and adjuvant chemotherapy is recommended, especially when vascular invasion or LN metastasis is confirmed.

Management of obstructive colon cancer: Current status, obstacles, and future directions.

Approximately 10%-18% of patients with colon cancer present with obstruction at the initial diagnosis. Despite active screening efforts, the incidence of obstructive colon cancer remains stable. Traditionally, emergency surgery has been indicated to treat patients with obstructive colon cancer. However, compared to patients undergoing elective surgery, the morbidity and mortality rates of patients requiring emergency surgery for obstructive colon cancer are high. With the advancement of colonoscopic techniques and equipment, a self-expandable metal stent (SEMS) was introduced to relieve obstructive symptoms, allowing the patient's general condition to be restored and for them undergo elective surgery. As the use of SEMS placement is growing, controversies about its application in potentially curable diseases have been raised. In this review, the short- and long-term outcomes of different treatment strategies, particularly emergency surgery vs SEMS placement followed by elective surgery in resectable, locally advanced obstructive colon cancer, are described based on the location of the obstructive cancer lesion. Controversies regarding each treatment strategy are discussed. To overcome current obstacles, a potential diagnostic method using circulating tumor DNA and further research directions incorporating neoadjuvant chemotherapy are introduced.

Adjuvant chemotherapy for patients with stage II high-risk and III colon cancer: Hindering factors to adherence and impact on long-term survival.

Purpose: Adjuvant chemotherapy is recommended after curative surgery in patients with colon cancer of high-risk stage II and stage III. However, a considerable number of patients cannot complete the scheduled adjuvant treatment for various reasons. This study investigates the hindering factors to the adherence to adjuvant chemotherapy and their impact on long-term survival. Methods: A retrospective study was conducted for patients with colon cancer and had curative resection from 2009 to 2014. Among patients with pathologic stage II and III, stage II with low-risk features, double primary cancers, R2 resection cases were excluded. Patients were grouped into three groups: no-adjuvant therapy, adjuvant therapy for less than 3 months, and more than 3 months. Factors for withdrawal and the oncologic outcome were analyzed. Results: Of 571 patients, adjuvant chemotherapy was recommended in 403. One hundred and sixteen patients (28.8%) did not receive adjuvant chemotherapy, 78 (19.4%) withdrew within 3 months, and 209 (51.9%) maintained for more than 3 months. Factors for not receiving adjuvant chemotherapy or withdrawing within 3 months were older than 70 and American Society of Anesthesiologists class 3 or higher. Main reasons for discontinuation before 3 months were chemotoxicity and patient's refusal. The long-term oncologic outcome of the patients who received adjuvant chemotherapy for more than 3 months was significantly better than others. Conclusion: No-adjuvant therapy or receiving them for lesser than 3 months is significantly affected by the patient's performance status and social support, which coincides with a poor oncologic outcome. Social support and rehabilitation system may help to improve the survival outcome.