Para-aortic Lymph Node Dissection for Colorectal Cancer: Predicting Pathologic Lymph Node Positivity and Optimizing Outcomes.

INTRODUCTION: In colorectal cancer, the presence of para-aortic lymph nodes (PALN) indicates extraregional disease. Appropriately selecting patients for whom PALN dissection will provide oncologic benefit remains challenging. This study identified factors to predict survival among patients undergoing PALN dissection for colorectal cancer. METHODS: An institutional database was queried for patients who underwent curative-intent resection of clinically positive PALN for colorectal cancer between 2007 and 2020. Preoperative radiologic images were reviewed, and patients who did and did not have positive PALN on final pathology were compared. Survival analysis was performed to evaluate the impact of pathologically positive PALN on recurrence-free (RFS) and overall survival (OS). RESULTS: Of 74 patients who underwent PALN dissection, 51 had PALN metastasis at the time of primary tumor diagnosis, whereas 23 had metachronous PALN disease. Preoperative chemotherapy ± radiotherapy was given in 60 cases (81.1%), and 28 (37.8%) had pathologically positive PALN. Independent factors associated with positive PALN pathology included metachronous PALN disease and pretreatment and posttreatment radiographically abnormal PALN. On multivariable analysis, pathologically positive PALN was significantly associated with decreased RFS (hazard ratio 3.90) and OS (HR 4.49). Among patients with pathologically positive PALN, well/moderately differentiated histology was associated with better OS, and metachronous disease trended toward an association with better OS. CONCLUSIONS: Pathologically positive PALN are associated with poorer RFS and OS after PALN dissection for colorectal cancer. Clinicopathologic factors may predict pathologic PALN positivity. Curative-intent surgery may provide benefit, especially in patients with well-to-moderately differentiated primary tumors and possibly metachronous PALN disease.

The Learning Curve for Robotic Lateral Pelvic Lymph Node Dissection for Rectal Cancer: A View from the West.

BACKGROUND: Lateral pelvic lymph-node dissection is performed for selected patients with rectal cancer with persistent lateral nodal disease after neoadjuvant therapy. This technique has been slow to be adopted in the West due to concerns regarding technical difficulty. This is the first report on the learning curve for lateral pelvic lymph node dissection in the US or Europe. OBJECTIVE: The aim of this study was to analyze the learning curve associated with robotic lateral pelvic lymph node dissection. DESIGN: Retrospective observational cohort. SETTING: Tertiary academic cancer center. PATIENTS: Consecutive patients from 2012 to 2021. INTERVENTION: All patients underwent robotic lateral pelvic lymph node dissection. MAIN OUTCOME MEASURES: The primary endpoints were the learning curves for maximum number of nodes retrieved and urinary retention which was evaluated with simple cumulative-sum and two-sided Bernoulli cumulative-sum charts. RESULTS: Fifty-four procedures were included. A single-surgeon (n = 35) and an institutional learning curve are presented in the analysis. In the single-surgeon learning curve, a turning point marking the end of a learning phase was detected at the 12th procedure for the number of retrieved nodes and at the 20th for urinary retention. In the institutional learning curve analysis, two turning points were identified at the 13th and 26th procedures indicating progressive improvements for the number of retrieved nodes and at the 27th for urinary retention. No sustained alarm signals were detected at any time point. LIMITATIONS: The retrospective nature, small sample size and the referral center nature of the reporting institution that may limit generalizability. CONCLUSIONS: In a setting of institutional experience with robotic colorectal surgery including beyond TME resections, the learning curve for robotic lateral pelvic lymph node dissection is acceptably short. Our results demonstrate feasibility of acquisition of this technique in a controlled setting, with sufficient case volume and proctoring can optimize the learning curve. See Video Abstract.

Early Postoperative Prediction of Complications and Readmission After Colorectal Cancer Surgery Using an Artificial Neural Network.

BACKGROUND: Early predictors of postoperative complications can risk-stratify patients undergoing colorectal cancer surgery. However, conventional regression models have limited power to identify complex nonlinear relationships among a large set of variables. We developed artificial neural network models to optimize the prediction of major postoperative complications and risk of readmission in patients undergoing colorectal cancer surgery. OBJECTIVE: The aim of this study was to develop an artificial neural network model to predict postoperative complications using postoperative laboratory values, and compare these models' accuracy to standard regression methods. DESIGN: This retrospective study included patients who underwent elective colorectal cancer resection between January 1, 2016, and July 31, 2021. Clinical data, cancer stage, and laboratory data from postoperative day 1 to 3 were collected. Models of complications and readmission risk were created using multivariable logistic regression and single-layer neural networks. SETTING: National Cancer Institute-Designated Comprehensive Cancer Center. PATIENTS: Adult colorectal cancer patients. MAIN OUTCOME MEASURES: Accuracy of predicting postoperative major complication, readmission and anastomotic leak using the area under the receiver-operating characteristic curve. RESULTS: Neural networks had larger areas under the curve for predicting major complications compared to regression models (neural network 0.811; regression model 0.724, p < 0.001). Neural networks also showed an advantage in predicting anastomotic leak (p = 0.036) and readmission using postoperative day 1-2 values (p = 0.014). LIMITATIONS: Single-center, retrospective design limited to cancer operations. CONCLUSIONS: In this study, we generated a set of models for early prediction of complications after colorectal surgery. The neural network models provided greater discrimination than the models based on traditional logistic regression. These models may allow for early detection of postoperative complications as soon as postoperative day 2. See Video Abstract.

Anatomic Basis of Rectal Cancer Staging: Clarifying Controversies and Misconceptions.

Rectal MRI provides a detailed depiction of pelvic anatomy; specifically, the relationship of the tumor to key anatomic structures, including the mesorectal fascia, anterior peritoneal reflection, and sphincter complex. However, anatomic inconsistencies, pitfalls, and confusion exist, which can have a strong impact on interpretation and treatment. These areas of confusion include the definition of the rectum itself, specifically differentiation of the rectum from the anal canal and the sigmoid colon, and delineation of the high versus low rectum. Other areas of confusion include the relative locations of the mesorectal fascia and peritoneum and their significance in staging and treatment, the difference between the mesorectal fascia and circumferential resection margin, involvement of the sphincter complex, and evaluation of lateral pelvic lymph nodes. The impact of these anatomic inconsistencies and sources of confusion is significant, given the importance of MRI in depicting the anatomic relationship of the tumor to critical pelvic structures, to triage surgical resection and neoadjuvant chemoradiotherapy with the goal of minimizing local recurrence. Evolving treatment paradigms also place MRI central in management of rectal cancer. ©RSNA, 2024.

Perioperative and oncological outcomes following robotic en bloc multivisceral resection for colorectal cancer.

AIM: As multidisciplinary treatment strategies for colorectal cancer have improved, aggressive surgical resection has become commonplace. Multivisceral and extended resections offer curative-intent resection with significant survival benefit. However, limited data exist regarding the feasibility and oncological efficacy of performing extended resection via a minimally invasive approach. The aim of this study was to determine the perioperative and long-term outcomes following robotic extended resection for colorectal cancer. METHOD: We describe the population of patients undergoing robotic multivisceral resection for colorectal cancer at our single institution. We evaluated perioperative details and investigated short- and long-term outcomes, using the Kaplan-Meier method to analyse overall and recurrence-free survival. RESULTS: Among the 86 patients most tumours were T3 (47%) or T4 (47%) lesions in the rectum (78%). Most resections involved the anterior compartment (72%): bladder (n = 13), seminal vesicle/vas deferens (n = 27), ureter (n = 6), prostate (n = 15) and uterus/vagina/adnexa (n = 27). Three cases required conversion to open surgery; 10 patients had grade 3 complications. The median hospital stay was 4 days. Resections were R0 (>1 mm) in 78 and R1 (0 to ≤1 mm) in 8, with none being R2. The average nodal yield was 26 and 48 (55.8%) were pN0. Three-year overall survival was 88% and median progression-free survival was 19.4 months. Local recurrence was 6.1% and distant recurrence was 26.1% at 3 years. CONCLUSION: Performance of multivisceral and extended resection on the robotic platform allows patients the benefit of minimally invasive surgery while achieving oncologically sound resection of colorectal cancer.

Prognostic factors of para-aortic lymph node metastasis from colorectal cancer in highly selected patients undergoing para-aortic lymph node dissection.

PURPOSE: We investigated the surgical outcomes of para-aortic lymph node (PALN) dissection in patients with colorectal cancer and assessed the prognostic factors related to the survival. METHODS: This single-center retrospective study included 31 patients with synchronous or metachronous PALN metastasis from colorectal cancer who underwent PALN dissection between January 2006 and December 2018. RESULTS: Twenty-one patients had synchronous PALN metastasis, and 10 had metachronous PALN metastasis. Seven patients had either simultaneous distant metastasis or a history of distant metastasis other than PALN metastasis at the time of PALN dissection. Eighteen patients underwent adjuvant chemotherapy. The 5-year overall and recurrence-free survival rates were 54.2 and 17.2%, respectively. A multivariable analysis revealed that rectal cancer, metachronous PALN metastasis, and three or more pathological PALN metastases were significantly poor prognostic factors for the recurrence-free survival. Among patients with rectal cancer, lower rectal cancer and lateral pelvic lymph node metastasis were poor prognostic factors for the overall survival. CONCLUSION: Curative PALN dissection for PALN metastasis from colorectal cancer is feasible with favorable long-term outcomes. A multidisciplinary approach, including surgery and chemotherapy, is needed for colorectal cancer with PALN metastasis to improve the long-term outcomes.

Stoma-free Survival After Rectal Cancer Resection With Anastomotic Leakage: Development and Validation of a Prediction Model in a Large International Cohort.

OBJECTIVE: To develop and validate a prediction model (STOMA score) for 1-year stoma-free survival in patients with rectal cancer (RC) with anastomotic leakage (AL). BACKGROUND: AL after RC resection often results in a permanent stoma. METHODS: This international retrospective cohort study (TENTACLE-Rectum) encompassed 216 participating centres and included patients who developed AL after RC surgery between 2014 and 2018. Clinically relevant predictors for 1-year stoma-free survival were included in uni and multivariable logistic regression models. The STOMA score was developed and internally validated in a cohort of patients operated between 2014 and 2017, with subsequent temporal validation in a 2018 cohort. The discriminative power and calibration of the models' performance were evaluated. RESULTS: This study included 2499 patients with AL, 1954 in the development cohort and 545 in the validation cohort. Baseline characteristics were comparable. One-year stoma-free survival was 45.0% in the development cohort and 43.7% in the validation cohort. The following predictors were included in the STOMA score: sex, age, American Society of Anestesiologist classification, body mass index, clinical M-disease, neoadjuvant therapy, abdominal and transanal approach, primary defunctioning stoma, multivisceral resection, clinical setting in which AL was diagnosed, postoperative day of AL diagnosis, abdominal contamination, anastomotic defect circumference, bowel wall ischemia, anastomotic fistula, retraction, and reactivation leakage. The STOMA score showed good discrimination and calibration (c-index: 0.71, 95% CI: 0.66-0.76). CONCLUSIONS: The STOMA score consists of 18 clinically relevant factors and estimates the individual risk for 1-year stoma-free survival in patients with AL after RC surgery, which may improve patient counseling and give guidance when analyzing the efficacy of different treatment strategies in future studies.

Adding Induction Chemotherapy Before Chemoradiotherapy with Total Mesorectal Excision and Selective Lateral Lymph Node Dissection for Patients with Poor-Risk, Locally Advanced, Mid-to-Low Rectal Cancer May Improve Oncologic Outcomes: A Propensity Score-Matched Analysis.

BACKGROUND: This study aimed to investigate whether the addition of induction chemotherapy before chemoradiotherapy (CRT) and total mesorectal excision (TME) with selective lateral lymph node dissection improves disease-free survival for patients with poor-risk, mid-to-low rectal cancer. METHODS: The authors' institutional prospective database was queried for consecutive patients with clinical stage II or III, primary, poor-risk, mid-to-low rectal cancer who received neoadjuvant treatment followed by TME from 2004 to 2019. The outcomes for the patients who received induction chemotherapy before neoadjuvant CRT (induction-CRT group) were compared (via log-rank tests) with those for a propensity score-matched cohort of patients who received neoadjuvant CRT without induction chemotherapy (CRT group). RESULTS: From 715 eligible patients, the study selected two matched cohorts with 130 patients each. The median follow-up duration was 5.4 years for the CRT group and 4.1 years for the induction-CRT group. The induction-CRT group had significantly higher rates of 3-year disease-free survival (83.5 % vs 71.4 %; p = 0.015), distant metastasis-free survival (84.3 % vs 75.2 %; p = 0.049), and local recurrence-free survival (98.4 % vs 94.4 %; p = 0.048) than the CRT group. The pathologically complete response rate also was higher in the induction-CRT group than in the CRT group (26.2 % vs 10.0 %; p < 0.001). Postoperative major complications (Clavien-Dindo classification ≥III) did not differ significantly between the two groups (12.3 % vs 10.8 %; p = 0.698). CONCLUSIONS: The addition of induction chemotherapy to neoadjuvant CRT appeared to improve oncologic outcomes significantly, including disease-free survival, for the patients with poor-risk, mid-to-low rectal cancer who underwent TME using selective lateral lymph node dissection.

Hepatectomy Before Primary Tumor Resection as Preferred Approach for Synchronous Liver Metastases from Rectal Cancer.

BACKGROUND: For patients with synchronous liver metastases (LM) from rectal cancer, a consensus on surgical sequencing is lacking. We compared outcomes between the reverse (hepatectomy first), classic (primary tumor resection first), and combined (simultaneous hepatectomy and primary tumor resection) approaches. METHODS: A prospectively maintained database was queried for patients with rectal cancer LM diagnosed before primary tumor resection who underwent hepatectomy for LM from January 2004 to April 2021. Clinicopathological factors and survival were compared between the three approaches. RESULTS: Among 274 patients, 141 (51%) underwent the reverse approach; 73 (27%), the classic approach; and 60 (22%), the combined approach. Higher carcinoembryonic antigen level at LM diagnosis and higher number of LM were associated with the reverse approach. Combined approach patients had smaller tumors and underwent less complex hepatectomies. More than eight cycles of pre-hepatectomy chemotherapy and maximum diameter of LM > 5 cm were independently associated with worse overall survival (OS) (p = 0.002 and 0.027, respectively). Although 35% of reverse-approach patients did not undergo primary tumor resection, OS did not differ between groups. Additionally, 82% of incomplete reverse-approach patients ultimately did not require diversion during follow-up. RAS/TP53 co-mutation was independently associated with lack of primary resection with the reverse approach (odds ratio: 0.16, 95% CI 0.038-0.64, p = 0.010). CONCLUSIONS: The reverse approach results in survival similar to that of combined and classic approaches and may obviate primary rectal tumor resections and diversions. RAS/TP53 co-mutation is associated with a lower rate of completion of the reverse approach.

Stoma-free survival after anastomotic leak following rectal cancer resection: worldwide cohort of 2470 patients.

BACKGROUND: The optimal treatment of anastomotic leak after rectal cancer resection is unclear. This worldwide cohort study aimed to provide an overview of four treatment strategies applied. METHODS: Patients from 216 centres and 45 countries with anastomotic leak after rectal cancer resection between 2014 and 2018 were included. Treatment was categorized as salvage surgery, faecal diversion with passive or active (vacuum) drainage, and no primary/secondary faecal diversion. The primary outcome was 1-year stoma-free survival. In addition, passive and active drainage were compared using propensity score matching (2 : 1). RESULTS: Of 2470 evaluable patients, 388 (16.0 per cent) underwent salvage surgery, 1524 (62.0 per cent) passive drainage, 278 (11.0 per cent) active drainage, and 280 (11.0 per cent) had no faecal diversion. One-year stoma-free survival rates were 13.7, 48.3, 48.2, and 65.4 per cent respectively. Propensity score matching resulted in 556 patients with passive and 278 with active drainage. There was no statistically significant difference between these groups in 1-year stoma-free survival (OR 0.95, 95 per cent c.i. 0.66 to 1.33), with a risk difference of -1.1 (95 per cent c.i. -9.0 to 7.0) per cent. After active drainage, more patients required secondary salvage surgery (OR 2.32, 1.49 to 3.59), prolonged hospital admission (an additional 6 (95 per cent c.i. 2 to 10) days), and ICU admission (OR 1.41, 1.02 to 1.94). Mean duration of leak healing did not differ significantly (an additional 12 (-28 to 52) days). CONCLUSION: Primary salvage surgery or omission of faecal diversion likely correspond to the most severe and least severe leaks respectively. In patients with diverted leaks, stoma-free survival did not differ statistically between passive and active drainage, although the increased risk of secondary salvage surgery and ICU admission suggests residual confounding.

International standardization and optimization group for intersphincteric resection (ISOG-ISR): modified Delphi consensus on anatomy, definition, indication, surgical technique, specimen description and functional outcome.

AIM: Intersphincteric resection (ISR) is an oncologically complex operation for very low-lying rectal cancers. Yet, definition, anatomical description, operative indications and operative approaches to ISR are not standardized. The aim of this study was to standardize the definition of ISR by reaching international consensus from the experts in the field. This standardization will allow meaningful comparison in the literature in the future. METHOD: A modified Delphi approach with three rounds of questionnaire was adopted. A total of 29 international experts from 11 countries were recruited for this study. Six domains with a total of 37 statements were examined, including anatomical definition; definition of intersphincteric dissection, intersphincteric resection (ISR) and ultra-low anterior resection (uLAR); indication for ISR; surgical technique of ISR; specimen description of ISR; and functional outcome assessment protocol. RESULTS: Three rounds of questionnaire were performed (response rate 100%, 89.6%, 89.6%). Agreement (≥80%) reached standardization on 36 statements. CONCLUSION: This study provides an international expert consensus-based definition and standardization of ISR. This is the first study standardizing terminology and definition of deep pelvis/anal canal anatomy from a surgical point of view. Intersphincteric dissection, ISR and uLAR were specifically defined for precise surgical description. Indication for ISR was determined by the rectal tumour's maximal radial infiltration (T stage) below the levator ani. A new surgical definition of T3isp was reached by consensus to define T3 low rectal tumours infiltrating the intersphincteric plane. A practical flowchart for surgical indication for uLAR/ISR/abdominoperineal resection was developed. A standardized ISR surgical technique and functional outcome assessment protocol was defined.

Magnetic Resonance Imaging Directed Surgical Decision Making for Lateral Pelvic Lymph Node Dissection in Rectal Cancer After Total Neoadjuvant Therapy (TNT).

OBJECTIVE: Lateral pelvic lymph node (LPLN) metastases are an important cause of preventable local failure in rectal cancer. The aim of this study was to evaluate clinical and oncological outcomes following magnetic resonance imaging (MRI)-directed surgical selection for lateral pelvic lymph node dissection (LPLND) after total neoadjuvant therapy (TNT). METHODS: A retrospective consecutive cohort analysis was performed of rectal cancer patients with enlarged LPLN on pretreatment MRI. Patients were categorized as LPLND or non-LPLND. The main outcomes were lateral local recurrence rate, perioperative and oncological outcomes and factors associated with decision making for LPLND. RESULTS: A total of 158 patients with enlarged pretreatment LPLN and treated with TNT were identified. Median follow-up was 20 months (interquartile range 10-32). After multidisciplinary review, 88 patients (56.0%) underwent LPLND. Mean age was 53 (SD±12) years, and 54 (34.2%) were female. Total operative time (509 vs 429 minutes; P =0.003) was greater in the LPLND group, but median blood loss ( P =0.70) or rates of major morbidity (19.3% vs 17.0%) did not differ. LPLNs were pathologically positive in 34.1%. The 3-year lateral local recurrence rates (3.4% vs 4.6%; P =0.85) did not differ between groups. Patients with LPLNs demonstrating pretreatment heterogeneity and irregular margin (odds ratio, 3.82; 95% confidence interval: 1.65-8.82) or with short-axis ≥5 mm post-TNT (odds ratio 2.69; 95% confidence interval: 1.19-6.08) were more likely to undergo LPLND. CONCLUSIONS: For rectal cancer patients with evidence of LPLN metastasis, the appropriate selection of patients for LPLND can be facilitated by a multidisciplinary MRI-directed approach with no significant difference in perioperative or oncologic outcomes.

Prognosis for Poorly Differentiated, High-Grade Rectal Neuroendocrine Carcinomas.

INTRODUCTION: Rectal neuroendocrine carcinomas (rNECs) are poorly characterized and, given their aggressive nature, optimal management is not well-established. We therefore sought to describe clinicopathologic traits, treatment details, and survival patterns for patients with rNECs. METHODS: Patients captured in the National Cancer Database (NCDB; 2004-2016) with rNECs managed with observation, chemotherapy, or proctectomy ± chemotherapy were considered for analysis. RESULTS: The inclusion criteria were met by 777 patients. Mean age was 62.4 years, 45% were male, 80% were Caucasian, 40% presented with lymph nodes metastases, and 49% presented with distant metastases. Chemotherapy and surgical resection were administered in 72 and 19% of cases, respectively. Median overall survival (OS) was 0.83 years (1 year, 41%; 3 years, 13%; 5 years, 10%). During the study interval, 659 (85%) patients died, with a median follow-up of 0.79 years. On multivariable analysis, age ≥60 years, male sex, and distant metastases were associated with worse survival; surgical resection and administration of chemotherapy were associated with a reduced risk of death. Among non-metastatic patients treated with surgical resection, administration of chemotherapy was protective, while a positive lymph node ratio (LNR) ≥42% (median value) was associated with an increased risk of death. There was no difference in the number of examined lymph nodes between LNR cohorts. CONCLUSIONS: Patients with rNECs experience dismal survival outcomes, including those with non-metastatic disease treated with curative-intent surgical resection. Neoadjuvant therapy can serve as a useful biologic test, and surgical resection should be judiciously employed.

What is the Risk for Peritoneal Metastases and Survival Afterwards in T4 Colon Cancers?

BACKGROUND: Patients with T4 colon adenocarcinomas have an increased risk of peritoneal metastases (PM) but the histopathologic risk factors for its development are not well-described. OBJECTIVE: The purpose of this study was to determine factors associated with PM, time to recurrence, and survival after recurrence among patients with T4 colon cancer. PATIENTS AND METHODS: Patients with pathologic T4 colon cancer who underwent curative resection from 2005 to 2017 were identified from a prospectively maintained institutional database and classified by recurrence pattern: (a) none - 68.8%; (b) peritoneal only - 7.9%; (c) peritoneal and extraperitoneal - 9.9%; and (d) extraperitoneal only - 13.2%. Associations between PM development and patient, primary tumor, and treatment factors were assessed. RESULTS: Overall, 151 patients were analyzed, with a median follow-up of 66.2 months; 27 patients (18%) developed PM (Groups B and C) and 20 (13%) patients recurred at non-peritoneal sites only (Group D). Median time to developing metastases was shorter for Groups B and C compared with Group D (B and C: 13.7 months; D: 46.7 months; p = 0.022). Tumor deposits (TDs) and nodal stage were associated with PM (p < 0.05), and TDs (p = 0.048) and LVI (p = 0.015) were associated with additional extraperitoneal recurrence. Eleven (41%) patients with PM underwent salvage surgery, and median survival after recurrence was associated with the ability to undergo cytoreduction (risk ratio 0.20, confidence interval 0.06-0.70). CONCLUSION: PM risk after resection of T4 colon cancer is independently associated with factors related to lymphatic spread, such as N stage and TDs. Well-selected patients can undergo cytoreduction with long-term survival. These findings support frequent postoperative surveillance and aggressive early intervention, including cytoreduction.

Current controversies in TNM for the radiological staging of rectal cancer and how to deal with them: results of a global online survey and multidisciplinary expert consensus.

OBJECTIVES: To identify the main problem areas in the applicability of the current TNM staging system (8th ed.) for the radiological staging and reporting of rectal cancer and provide practice recommendations on how to handle them. METHODS: A global case-based online survey was conducted including 41 image-based rectal cancer cases focusing on various items included in the TNM system. Cases reaching < 80% agreement among survey respondents were identified as problem areas and discussed among an international expert panel, including 5 radiologists, 6 colorectal surgeons, 4 radiation oncologists, and 3 pathologists. RESULTS: Three hundred twenty-one respondents (from 32 countries) completed the survey. Sixteen problem areas were identified, related to cT staging in low-rectal cancers, definitions for cT4b and cM1a disease, definitions for mesorectal fascia (MRF) involvement, evaluation of lymph nodes versus tumor deposits, and staging of lateral lymph nodes. The expert panel recommended strategies on how to handle these, including advice on cT-stage categorization in case of involvement of different layers of the anal canal, specifications on which structures to include in the definition of cT4b disease, how to define MRF involvement by the primary tumor and other tumor-bearing structures, how to differentiate and report lymph nodes and tumor deposits on MRI, and how to anatomically localize and stage lateral lymph nodes. CONCLUSIONS: The recommendations derived from this global survey and expert panel discussion may serve as a practice guide and support tool for radiologists (and other clinicians) involved in the staging of rectal cancer and may contribute to improved consistency in radiological staging and reporting. KEY POINTS: • Via a case-based online survey (incl. 321 respondents from 32 countries), we identified 16 problem areas related to the applicability of the TNM staging system for the radiological staging and reporting of rectal cancer. • A multidisciplinary panel of experts recommended strategies on how to handle these problem areas, including advice on cT-stage categorization in case of involvement of different layers of the anal canal, specifications on which structures to include in the definition of cT4b disease, how to define mesorectal fascia involvement by the primary tumor and other tumor-bearing structures, how to differentiate and report lymph nodes and tumor deposits on MRI, and how to anatomically localize and stage lateral lymph nodes. • These recommendations may serve as a practice guide and support tool for radiologists (and other clinicians) involved in the staging of rectal cancer and may contribute to improved consistency in radiological staging and reporting.

Lymph Node Mapping in Transverse Colon Cancer Treated Using Laparoscopic Colectomy With D3 Lymph Node Dissection.

BACKGROUND: Laparoscopic surgery for transverse colon cancer has been excluded from 7 randomized trials for various reasons. The optimal procedure for transverse colon cancer remains controversial. OBJECTIVE: This study aimed to analyze the patterns of lymph node metastasis in transverse colon cancer and to report short- and long-term outcomes of the treatment procedures. DESIGN: This was a single-center retrospective study. SETTINGS: This study was conducted at Cancer Institute Hospital, Tokyo, Japan. PATIENTS: We enrolled 252 patients who underwent laparoscopic surgery for transverse colon cancer. INTERVENTIONS: The transverse colon was divided into 3 segments, and the procedures for transverse colon cancer were based on these segments, as follows: right hemicolectomy, transverse colectomy, and left hemicolectomy. MAIN OUTCOME MEASURES: Postoperatively, the surgeons identified and mapped the lymph nodes from specimens and performed formalin fixation separately to compare the results of the pathological findings. RESULTS: For right-sided, middle-segment, and left-sided transverse colon cancers, the frequency of lymph node metastases was 28.2%, 19.2%, and 19.2%. Skipped lymph node metastasis occurred in right-sided and left-sided transverse colon cancers but not in middle-segment transverse colon cancers. The pathological vascular invasion rate was significantly higher in right and left hemicolectomy than in transverse colectomy. For right hemicolectomy, transverse colectomy, and left hemicolectomy, 5-year overall survival rates were 96.3%, 92.7%, and 93.7%, and relapse-free survival rates were 92.4%, 88.3%, and 95.5%. In multivariate analysis, the independent risk factor for relapse-free survival was lymph node metastasis. LIMITATIONS: Selection bias and different backgrounds may have influenced surgical and long-term outcomes. CONCLUSION: Laparoscopic surgery for transverse colon cancer may be a feasible technique. Harvested lymph node mapping after laparoscopic resection based on D3 lymphadenectomy may help guide the field of dissection when managing patients who have transverse colon cancer. The only independent prognostic factor for relapse-free survival was node-positive cancer. See Video Abstract at http://links.lww.com/DCR/B706.MAPEO DE GANGLIOS LINFÁTICOS EN CÁNCER DE COLON TRANSVERSO TRATADO MEDIANTE COLECTOMÍA LAPAROSCÓPICA CON LINFADENECTOMÍA D3ANTECEDENTES:La cirugía laparoscópica en casos de cáncer de colon transverso fué excluida de siete estudios randomizados mayores por diversas razones. El procedimiento más idóneo en casos de cáncer de colon transverso, sigue siendo controvertido.OBJETIVO:Analizar los patrones de las metástasis en los ganglios linfáticos en casos de cáncer de colon transverso y reportar los resultados a corto y largo plazo de los diferentes procedimientos para su tratamiento.DISEÑO:Estudio retrospectivo en un solo centro de referencia.AJUSTE:Estudio llevado a cabo en el Hospital del Instituto del Cancer, Tokio, Japón.PACIENTES:Fueron incluidos 252 pacientes, sometidos a cirugía laparoscópica por cáncer de colon transverso.INTERVENCIONES:El colon transverso fué dividido en tres segmentos y los procedimientos en casos de cáncer se basaron sobre estos segmentos del tranverso, de la siguiente manera: hemicolectomía derecha, colectomía transversa y hemicolectomía izquierda.PRINCIPALES MEDIDAS DE RESULTADO:En el postoperatorio, los cirujanos identificaron y mapearon los ganglios linfáticos de las piezas quirúrgicas y las fijaron con formaldehido por separado para así poder comparar los resultados con los hallazgos histopatológicos.RESULTADOS:En los cánceres de colon transverso del segmento derecho, del segmento medio y del segmento izquierdo, la frecuencia de metástasis en los ganglios linfáticos fue del 28,2%, 19,2% y 19,2%, respectivamente. Las metástasis en los ganglios linfáticos omitidos se produjo en los cánceres de colon transverso del lado derecho y del lado izquierdo, pero no en los cánceres de colon transverso del segmento medio. La tasa de invasión vascular patológica fue significativamente mayor en la hemicolectomía derecha e izquierda que en la colectomía transversa. Para la hemicolectomía derecha, colectomía transversa y hemicolectomía izquierda, las tasas de supervivencia general a cinco años fueron del 96,3%, 92,7% y 93,7%, y las tasas de supervivencia sin recaída fueron del 92,4%, 88,3% y 95,5%, respectivamente. En el análisis multivariado, el factor de riesgo independiente para la sobrevida sin recidiva fue la metástasis en los ganglios linfáticos.LIMITACIONES:El sesgo de selección y los diferentes antecedentes pueden haber influido en los resultados quirúrgicos a largo plazo.CONCLUSIONES:La cirugía laparoscópica en casos de cáncer de colon transverso puede ser una técnica factible. El mapeo de los ganglios linfáticos recolectados después de la resección laparoscópica basada en la linfadenectomía D3 puede ayudar a guiar el campo de la disección en el manejo de pacientes con cáncer de colon transverso. El único factor pronóstico independiente para el SLR fue el cáncer con ganglios positivos. Consulte Video Resumen en http://links.lww.com/DCR/B706. (Traducción-Dr. Xavier Delgadillo).

Incidence and Prognostic Value of Lavage Cytology in Colorectal Cancer.

BACKGROUND: Lavage cytology is a method to detect cancer cells released within the abdominal cavity. It has been widely utilized, in particular, for gastric cancer. However, its clinical significance has not yet been determined in colorectal cancer. OBJECTIVE: This study aimed to investigate the frequency of lavage cytology positivity and its influence on the prognosis of patients with colorectal cancer. DESIGN: This is a single-institution retrospective observational study. SETTING: This study was conducted at a comprehensive cancer center. PATIENTS: We retrospectively analyzed 3135 colorectal cancer cases from 2007 to 2013 at our institution. Intraoperative peritoneal washing cytology was performed just after the start of the operation. Fluids were centrifuged for 5 minutes at 2500 rotations per minute, cell pellets were smeared on microscope glass slides, and Papanicolaou staining was performed. MAIN OUTCOME MEASURES: The primary outcome was the 5-year overall survival rate. The secondary outcome was the 5-year recurrence rate. RESULTS: Lavage cytology positivity was detected in 19 (2.0%) and 86 (16.9%) cases of stage III and IV colorectal cancer; however, no positive cases were found in stage I and II colorectal cancer. Lavage cytology positivity was an independent prognostic factor in stage III and IV colorectal cancer in the multivariate analysis (5-year mortality HR 3.59 [1.69-7.64] in stage III, 2.23 [1.15-4.31] in stage IV). The prognosis of the 5-year survival rate was significantly worse in the lavage cytology-positive group in stages III and IV. In terms of recurrence, the results of the lavage cytology-positive group in stage III were similar to those of the lavage cytology-positive/negative group in stage IV (73.7%, 70.0%, and 75.0%). LIMITATIONS: This study was limited by its retrospective study design. CONCLUSIONS: Lavage cytology positivity is an independent prognostic and regulatory factor of stage IV colorectal cancer. See Video Abstract at http://links.lww.com/DCR/B770.INCIDENCIA Y VALOR PRONÓSTICO EN LA CITOLOGÍA DEL LAVADO PERITONEAL EN CÁNCER COLORECTALANTECEDENTES:La citología del lavado peritoneal es un método para detectar células cancerosas liberadas dentro de la cavidad abdominal. Se ha utilizado ampliamente, en particular para el cáncer gástrico. Sin embargo, aún no se ha determinado su importancia clínica en el cáncer colorrectal.OBJETIVO:Este estudio tuvo como objetivo investigar la frecuencia de positividad de la citología del lavado y su influencia en el pronóstico de los pacientes con cáncer colorrectal.DISEÑO:Este fue un estudio observacional retrospectivo de una sola institución.DISENTORNO CLÍNICO:El estudio se llevó a cabo en un centro oncológico integral.PACIENTES:Analizamos retrospectivamente 3.135 casos de cáncer colorrectal desde 2007 hasta 2013 en nuestra institución. La citología de lavado peritoneal intraoperatorio se realizó inmediatamente después del inicio de la operación. Los fluidos se centrifugaron durante 5 min a 2.500 rpm, los sedimentos celulares se extendieron sobre portaobjetos de vidrio de microscopio y se realizó la tinción con Papanicolaou.DISPRINCIPALES MEDIDAS DE VALORACIÓN:El primer resultado fueron las tasas de supervivencia general a 5 años. El segundo resultado las tasas de recurrencia a los 5 años.RESULTADOS:Se detectó positividad en la citología de lavado en 19 (2,0%) y 86 (16,9%) casos de cáncer colorrectal en estadio III y IV, respectivamente; sin embargo, no se encontraron casos positivos en el cáncer colorrectal en estadio I y II. La positividad de la citología de lavado fue un factor pronóstico independiente en el cáncer colorrectal en estadio III y IV en el análisis multivariado [cociente de riesgo de mortalidad a 5 años 3,59 (1,69-7,64), en estadio III, 2,23 (1,15-4,31), en estadio IV]. El pronóstico de la tasa de supervivencia a 5 años fue significativamente peor en el grupo con citología de lavado positiva en los estadios III y IV. En cuanto a la recurrencia, los resultados del grupo de lavado con citología positiva en el estadio III fueron similares a los del grupo de lavado con citología positiva / negativa en el estadio IV (73,7%, 70,0% y 75,0%).LIMITACIONES:Este estudio estuvo limitado por su diseño de estudio retrospectivo.CONCLUSIONES:La positividad de la citología de lavado es un factor pronóstico y regulador independiente del cáncer colorrectal en estadio IV. Consulte Video Resumen en http://links.lww.com/DCR/B770. (Traducción- Dr. Ingrid Melo).

Laparoscopic Versus Open Surgery for Locally Advanced Rectal Cancer: Five-Year Survival Outcomes in a Large, Multicenter, Propensity Score-Matched Cohort Study.

BACKGROUND: There is a paucity of evidence pertaining to long-term survival outcomes of laparoscopic versus open surgery for locally advanced rectal cancer. OBJECTIVE: This study aimed to evaluate the long-term survival outcomes of laparoscopic surgery for locally advanced rectal cancer and to investigate the recurrence pattern. DESIGN: This was a prospective analysis of a registered cohort. SETTINGS: This study was conducted at 69 institutions across Japan. PATIENTS: A total of 1500 patients with clinical stage II-III rectal cancer located below the peritoneal reflection between January 2010 and December 2011 were included. After propensity score matching, all eligible patients, including the matched patients registered in 2014, were prospectively followed up. MAIN OUTCOME MEASURES: Five-year relapse-free survival was the primary outcome. RESULTS: The median follow-up period was 5.6 years. Among the 964 matched patients, the 5-year relapse-free survival was 65.1% in the open group versus 63.5% in the laparoscopic group (HR 1.04; p = 0.71). Distant recurrences at rare sites, which were more frequently observed in the laparoscopic group, were significantly less salvaged (adjusted OR 0.74; p = 0.045). Postrecurrence 5-year overall survival was significantly better for patients who underwent salvage surgery than for those who did not; 55.3% vs 29.5% for patients with initial local recurrence ( p = 0.03) and 64.4% vs 30.7% for patients with distant recurrence alone ( p < 0.001). LIMITATIONS: Potential heterogeneity and influence of unknown confounding. CONCLUSIONS: Five-year follow-up data demonstrated that laparoscopic surgery for locally advanced rectal cancer was safely performed in terms of long-term prognosis. In addition, salvage surgery for recurrent lesions was associated with prolonged postrecurrence survival, both in patients with local and distant recurrence. However, recurrence at rare sites may require further investigation. See Video Abstract at http://links.lww.com/DCR/B793 . CIRUGA LAPAROSCPICA VERSUS CIRUGA ABIERTA EN CNCER DE RECTO LOCALMENTE AVANZADO RESULTADOS DE SUPERVIVENCIA A CINCO AOS EN UN ESTUDIO DE COHORTE DE GRAN MAGNITUD, MULTICNTRICO Y DE PAREAMIENTO POR PUNTAJE DE PROPENSIN: ANTECEDENTES:Existe una escasez de pruebas relacionadas con los resultados de supervivencia a largo plazo de la cirugía laparoscópica versus abierta para el cáncer de recto localmente avanzado.OBJETIVO:Este estudio tuvo como objetivo evaluar los resultados de supervivencia a largo plazo de la cirugía laparoscópica para el cáncer de recto localmente avanzado e investigar el patrón de recurrencia.DISEÑO:Fue un análisis prospectivo de una cohorte registrada.ENTORNO CLÍNICO:El estudio se llevó a cabo en 69 instituciones en todo Japón.PACIENTES:Se incluyó un total de 1500 pacientes con cáncer de recto en estadio clínico II-III ubicados por debajo de la reflección peritoneal, entre enero del 2010 y diciembre del 2011. Después del pareamiento por puntaje de propensión, se realizó un seguimiento prospectivo de todos los pacientes elegibles, incluidos los pacientes emparejados registrados en 2014.PRINCIPALES MEDIDAS DE VALORACIÓN:La supervivencia sin recaídas a cinco años fue el resultado primario.RESULTADOS:El período de seguimiento medio fue de 5,6 años. Entre los 964 pacientes emparejados, la supervivencia libre de recaída a 5 años fue del 65,1% en el grupo abierto frente al 63,5% en el grupo laparoscópico (cociente de riesgo 1,04; p = 0,71). Las recurrencias a distancia en sitios raros, que se observaron con mayor frecuencia en el grupo laparoscópico, tuvieron menor sobrevida (razón de posibilidades ajustada 0,74; p = 0,045). La supervivencia general a los 5 años después de la recidiva fue significativamente menor en los pacientes sometidos a una cirugía de rescate; 55,3% frente al 29,5% para los pacientes con recidiva local inicial ( p = 0,03) y 64,4% frente al 30,7% para los pacientes con recidiva a distancia sola ( p < 0,001).LIMITACIONES:Potencial heterogeneidad e influencia de factores de confusión desconocidos.CONCLUSIONES:El seguimiento a cinco años demostró que la cirugía laparoscópica para el cáncer de recto localmente avanzado es segura en términos de pronóstico a largo plazo. Además, la cirugía de rescate de las lesiones recurrentes se asoció con una mayor supervivencia posrecurrencia, tanto en pacientes con recurrencia local como a distancia. Sin embargo, la recurrencia en sitios raros puede requerir una mayor investigación. Consulte Video Resumen en http://links.lww.com/DCR/B793 . (Traducción- Dr. Ingrid Melo ).

Laparoscopic extraperitoneal colostomy has a lower risk of parastomal hernia and bowel obstruction than transperitoneal colostomy.

PURPOSE: Several studies indicate that an extraperitoneal colostomy can prevent the development of a parastomal hernia (PSH) as compared to a transperitoneal colostomy. However, the clinical value of laparoscopic extraperitoneal colostomy, and its influence on bowel obstruction and PSH remain unclear. The present study aimed to clarify the impact of laparoscopic extraperitoneal colostomy on the development of a PSH and bowel obstruction. METHODS: This study included 327 consecutive patients who underwent laparoscopic abdominoperineal resection or Hartmann's procedure between January 2013 and December 2019 after fulfilling selection criteria. The incidence of a PSH (Clavien-Dindo classification ≥ grade I) and bowel obstruction (≥ grade IIIa) in the transperitoneal and extraperitoneal route groups were analyzed using univariate and multivariate analysis. RESULTS: The patients were classified into transperitoneal (n = 222) and extraperitoneal (n = 105) route groups. The patient characteristics, except for body mass index and operative time, were comparable between the groups. A PSH and bowel obstruction occurred more frequently in the transperitoneal than in the extraperitoneal route group (17.1% vs. 1.9% and 15.3% vs. 6.7%, respectively; p < 0.01 and p = 0.03, respectively). The multivariate analysis showed that age ≥ 70 years, body mass index ≥ 22.4 kg/m2, and a transperitoneal route were independent risk factors for the development of a PSH, and a transperitoneal route was an independent risk factor for bowel obstruction. CONCLUSIONS: The transperitoneal route was identified as a risk factor for the development of both a PSH and bowel obstruction after laparoscopic abdominoperineal resection or Hartmann's procedure.

Management of inguinal lymph node metastases from rectal and anal canal adenocarcinoma.

AIM: The surgical treatment of inguinal lymph node (ILN) metastases secondary to anorectal adenocarcinoma remains controversial. This study aimed to clarify the surgical treatment and management of ILN metastasis according to its classification. METHODS: This retrospective, multi-centre, observational study included patients with synchronous or metachronous ILN metastases who were diagnosed with rectal or anal canal adenocarcinoma between January 1997 and December 2011. Treatment outcomes were analysed according to recurrence and prognosis. RESULTS: Among 1181 consecutively enrolled patients who received treatment for rectal or anal canal adenocarcinoma at 20 referral hospitals, 76 (6.4%) and 65 (5.5%) had synchronous and metachronous ILN metastases, respectively. Among 141 patients with ILN metastasis, differentiated carcinoma, solitary ILN metastasis and ILN dissection were identified as independent predictive factors associated with a favourable prognosis. No significant difference was found in the frequency of recurrence after ILN dissection between patients with synchronous (80.6%) or metachronous (81.0%) ILN metastases. Patients who underwent R0 resection of the primary tumour and ILN dissection had a 5-year survival rate of 41.3% after ILN dissection (34.1% and 53.1% for patients with synchronous and metachronous ILN metastases, respectively, P = 0.55). CONCLUSION: The ILN can be appropriately classified as a regional lymph node in rectal and anal canal adenocarcinoma. Moreover, aggressive ILN dissection might be effective in improving the prognosis of low rectal and anal canal adenocarcinoma with ILN metastases; thus, prophylactic ILN dissection is unnecessary.