Distal clearance margin of 1 cm or less: a safe distance in lower rectum cancer surgery

Impact of Microscopically Positive (≤1 mm) Distal Margins on Disease Recurrence in Rectal Cancer Treated by Neoadjuvant Chemoradiotherapy

BACKGROUND

The adequate distal resection margin is still controversial in rectal cancer treated by neoadjuvant chemoradiotherapy (nCRT). The aim of this study was to assess the impact of a distal margin of ≤1 mm on locoregional recurrence-free survival (LRRFS).

METHODS

Among 255 patients treated with nCRT and surgery at the National Cancer Institute of Milan, 83 (32.5%) had a distal margin of ≤1 mm and 172 (67.5%) had a distal margin of >1 mm. Survival analyses were performed to assess the impact of distal margin on 5-year LRRFS, as well as Cox survival analysis. The role of distal margin on survival was analyzed according to different tumor regression grades (TRGs).

RESULTS

The overall 5-year LRRFS rate was 77.6% with a distal margin of ≤1 mm vs. 88.3% with a distal margin of >1 mm (Log-rank p = 0.09). Only stage ypT4 was an independent predictor of worse LRRFS (HR 15.14, p = 0.026). The 5-year LRRFS was significantly lower in TRG3-5 patients with a distal margin of ≤1 mm compared to those with a distal margin of >1 mm (68.5% vs. 84.2%, p = 0.027), while no difference was observed in case of TRG1-2 (p = 0.77).

CONCLUSIONS

Low-responder rectal cancers after nCRT still require a distal margin of >1 mm to reduce the high likelihood of local relapse.

The Impact of Narrow and Infiltrated Distal Margin After Proctectomy for Rectal Cancer on Patients' Outcomes: a Systematic Review and Meta-analysis

Rectal cancer is a common tumor within a difficult anatomic constraint. Total mesorectal excision with longitudinal and circumferential free margins is considered imperative for good prognosis. In this article, the authors systematically reviewed all published literature with specific Mesh terms until the end of year 2019. Thereafter, retrieved articles were assessed using the Newcastle-Ottawa Scale and meta-analysis was conducted comparing local recurrence among 1-cm, 5-mm, and narrow (< 1-mm)/infiltrated margins. Thirty-nine articles were included in the study. Macroscopic distal margin < 1 cm carried a higher incidence of recurrence for those who did not receive neoadjuvant radiation, without affecting neither estimated overall nor disease-free survival. Less than 5-mm margin after radiation therapy is accepted oncologically. Infiltrated margins and narrow margins (< 1 mm) microscopically are associated with higher incidence of local recurrence and shorter overall and disease-free survival. Surgeons should aim at 1-cm safety margin in radiotherapy-naïve patients and microscopic free margin > 1 mm for those who received neoadjuvant therapy. The cost/benefit of reoperation for patients with infiltrated margins is still inadequately studied.

Is a Distal Resection Margin of ≤ 1 cm Safe in Patients with Intermediate- to Low-Lying Rectal Cancer? A Systematic Review and Meta-Analysis

BACKGROUND

It is generally accepted that the distal resection margin of intermediate- to low-lying rectal cancer should be greater than 2 cm and at least 1 cm in special cases. This study intends to investigate whether a distal resection margin ≤ 1 cm affects tumor outcomes for patients with intermediate- to low-lying rectal cancer.

METHODS

A systematic review of the literature was conducted. Sixteen studies included data for distal resection margins ≤ 1 cm (1684 cases) and > 1 cm (5877 cases), and 5 studies included survival data. Meta-analysis was used to compare the local recurrence rate and long-term survival of patients with distal resection margins > or ≤ 1 cm.

RESULTS

The local recurrence rate in the ≤ 1-cm margin group (9.5%) was 2.3% higher than that in the > 1-cm margin group (7.2%) according to a fixed-effects model (RR [95% CI] 1.42 [1.18, 1.70], P < 0.001). The overall survival results of the five 1-cm margin studies showed an HR (95% CI) of 0.96 (0.75, 1.24) (P = 0.78). Subgroup analysis showed that the local recurrence rate in the subgroup with perioperative treatment was 1.2% lower in the ≤ 1-cm margin group (8.3%) than in the > 1-cm margin group (9.5%) (RR [95% CI] 0.97 [0.63, 1.49], P = 0.90). In the surgery alone subgroup, the local recurrence rate was 4.7% higher in the ≤ 1-cm margin group (12.4%) than in the > 1-cm group (7.7%) (RR [95% CI] 1.76 [1.09, 2.83], P = 0.02).

CONCLUSIONS

For patients with intermediate- to low-lying rectal cancer undergoing surgery alone, a distal resection margin ≤ 1 cm may be not safe.

Effects of surgical approach on short- and long-term outcomes in early-stage rectal cancer: a multicenter, propensity score-weighted cohort study

BACKGROUND

Randomized controlled trials have been unable to demonstrate noninferiority of minimally invasive surgery for rectal cancer. The aim of this study was to assess oncologic resection success, short- and long-term morbidity, and overall survival by operative approach in a homogenous early-stage rectal cancer cohort.

METHODS

This is a multicenter, propensity score-weighted cohort study utilizing deidentified data from the National Cancer Database. Individuals who underwent a formal proctectomy for early-stage rectal cancer (T1-2, N0, M0) from 2010 to 2015 were included. The primary outcome was a composite variable indicating successful oncologic resection stratified by operative approach, defined as negative margins with at least 12 lymph nodes evaluated.

RESULTS

Among 3649 proctectomies for rectal adenocarcinoma, 1660 (45%) were approached open, 1461 (40%) laparoscopically, and 528 (15%) robotically. After propensity score weighting, compared to open approach, there were no differences in odds of successful oncologic resection (OR_adj = 1.07, 95% CI 0.9, 1.28 and OR_adj = 1.28, 95% CI 0.97, 1.7). Open approach was associated with longer mean (± SD) length of stay compared to laparoscopic (7.7 ± 0.18 vs. 6.5 ± 0.25 days, p < 0.001) and robotic (7.7 ± 0.18 vs. 6.3 ± 0.35 days, p < 0.001) approaches. In regard to 90-day mortality, compared to open approach, laparoscopic (OR_adj = 0.56, 95% CI 0.36, 0.88) and robotic (OR_adj = 0.45, 95% CI 0.22, 0.94) approaches were associated with a reduced odd of 90-day mortality. This mortality benefit persists in the long-term for laparoscopic approach (p = 0.003).

CONCLUSION

For individuals with early-stage rectal cancer treated with proctectomy, successful oncologic resection can be achieved irrespective of technical approach. Minimally invasive approaches provide short-term reduction in morbidity. Surgical approach must be tailored to each patient based on surgeon experience and judgement in collaboration with a multi-disciplinary team.

Oncological outcome of wide anatomic resection with partial mesorectal excision in patients with upper and middle rectal cancer

AIM

The aim was to investigate the influence of distal resection margin and extent of mesorectal excision on long-term oncological outcomes.

METHOD

Consecutive patients with upper and middle third rectal cancer from June 2006 to February 2016 were reviewed. Patients were divided into four groups depending on the distal margin considered as a surrogate marker of the extension of mesorectal excision (Q1 ≤10 mm, Q2 11-20 mm, Q3 21-30 mm, Q4 ≥31 mm). Local-recurrence-free survival (LRFS), disease-free survival (DFS) and overall survival (OS) were estimated. Cox regression models were used to investigate the influence of surgical and clinicopathological variables on prognosis by adjusting for confounding factors.

RESULTS

Two hundred and eleven patients with mid (125) and upper (86) rectal cancer underwent wide mesorectal excision. The median follow-up was 48.64 months (interquartile range 28-63). 17.5% patients developed recurrence. The 5-year LRFS, DFS and OS for all patients were 93.20%, 83.89% and 80.1%, respectively, with no statistically significant differences between groups (LRFS, P = 0.601; DFS, P = 0.487; OS, P = 0.468). In the multivariable analysis the recurrences and survival were associated with the quality of the mesorectum (LRFS, hazard ratio 10.629, 95% CI 2.324-48.610, P = 0.002; DFS, hazard ratio 2.789, 95% CI 1.314-5.922, P = 0.008).

CONCLUSION

A wide anatomical resection with partial mesorectal excision and shorter distal resection margin does not jeopardize the oncological outcomes.

Evaluating disparities in delivery of neoadjuvant guideline-based chemoradiation for rectal cancer: A multicenter, propensity score-weighted cohort study

BACKGROUND

Despite guideline recommendations, some patients still receive care inappropriate for their clinical stage of disease. Identification of factors that contribute to variation in guideline base care may help eradicate disparities in the treatment of early and locally advanced rectal cancer.

METHODS

The American College of Surgeons National Cancer Database from 2010 to 2015 was analyzed with propensity score weighting to identify factors associated with delivery and omission of neoadjuvant guideline-based chemoradiation (GBC) for those with early and locally advanced rectal cancer.

RESULTS

Only 74% of patients with rectal cancer received stage-appropriate neoadjuvant chemoradiation; 4544 (88%) of those with early stage disease and 8675 (68%) in locally advanced disease. Chemotherapy and radiotherapy were not planned in 27% and 34% respectively, of those who did not receive GBC. Factors associated with receipt of non-guideline-based neoadjuvant chemoradiation were age >65 years, Medicare insurance, treatment at a community facility, West-South-Central geography, having locally advanced disease, and Charlson-Deyo score >3. Receipt of ideal guideline-based neoadjuvant chemoradiation conferred a survival benefit at 5 years.

CONCLUSION

Patient and non-patient factors contribute to disparities in guideline-based delivery of neoadjuvant chemoradiation in the treatment of rectal cancer. Identification of these risk factors are important to help standardize care and improve survival outcomes.

Management of Low Rectal Cancer Complicating Ulcerative Colitis: Proposal of a Treatment Algorithm

Simple Summary

This article expresses the viewpoint of the authors’ management of low rectal cancer in ulcerative colitis (UC). This subject suffers from a paucity of literature and therefore management decision is very difficult to take. The aim of this paper is to provide a structured approach to a challenging situation. It is subdivided into two parts: a first part where the existing literature is reviewed critically, and a second part in which, on the basis of the literature review and their extensive clinical experience, a management algorithm is proposed by the authors to offer guidance to surgical and oncological practices. This text adds to the literature a useful guide for the treatment of these complex clinical scenarios.

Abstract

Low rectal Carcinoma arising at the background of Ulcerative Colitis poses significant management challenges to the clinicians. The complex decision-making requires discussion at the multidisciplinary team meeting. The published literature is scarce, and there are significant variations in the management of such patients. We reviewed treatment protocols and operative strategies; with the aim of providing a practical framework for the management of low rectal cancer complicating UC. A practical treatment algorithm is proposed.

The risk factors of local recurrence and distant metastasis on pT1/T2N0 mid-low rectal cancer after total mesorectal excision

Background

Radical resection is associated with good prognosis among patients with cT1/T2Nx rectal cancer. However, still some of the patients experienced cancer recurrence following radical resection. This study tried to identify the postoperative risk factors of local recurrence and distant metastasis separately.

Methods

This retrospective, single-center study comprised of 279 consecutive patients from Linkou branch of Chang Gung Memorial Hospital in 2005–2016 with rectal adenocarcinoma, pT1/T2N0M0 at distance from anal verge ≤ 8cm, who received curative radical resection.

Results

The study included 279 patients with pT1/pT2N0 mid-low rectal cancer with median follow-up of 73.5 months. Nineteen (6.8%) patients had disease recurrence in total. Nine (3.2%) of them had local recurrence, and fourteen (5.0%) of them had distant metastasis. Distal resection margin < 0.9 (cm) (hazard ratio = 4.9, p = 0.050) was the risk factor of local recurrence. Preoperative carcinoembryonic antigen (CEA) ≥ 5 ng/mL (hazard ratio = 9.3, p = 0.0003), lymph node yield (LNY) < 14 (hazard ratio = 5.0, p = 0.006), and distal resection margin < 1.4cm (hazard ratio = 4.0, p = 0.035) were the risk factors of distant metastasis.

Conclusion

For patients with pT1/pT2N0 mid-low rectal cancer, current multidisciplinary treatment brings acceptable survival outcome. Insufficient distal resection margin attracted the awareness of risk factors for local recurrence and distant metastasis as a foundation for future research.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02223-4.

Functional outcome and quality of life following treatment for rectal cancer

Introduction Over the last decades, treatment for rectal cancer has substantially improved with development of new surgical options and treatment modalities. With the improvement of survival, functional outcome and quality of life are getting more attention.

Study objective To provide an overview of current modalities in rectal cancer treatment, with particular emphasis on functional outcomes and quality of life.

Results Functional outcomes after rectal cancer treatment are influenced by patient and tumor characteristics, surgical technique, the use of preoperative radiotherapy and the method and level of anastomosis. Sphincter preserving surgery for low rectal cancer often results in poor functional outcomes that impair quality of life, referred to as low anterior resection syndrome. Abdominoperineal resection imposes the need for a permanent stoma but avoids the risk of this syndrome. Contrary to general belief, long-term quality of life in patients with a permanent stoma is similar to those after sphincter preserving surgery for low rectal cancer.

Conclusion All patients should be informed about the risks of treatment modalities. Decision on rectal cancer treatment should be individualized since not all patients may benefit from a sphincter preserving surgery “at any price”. Non-resection treatment should be the future focus to avoid the need of a permanent stoma and bowel dysfunction.

Dual modal spectroscopic tissue scanner for colorectal cancer diagnosis

BACKGROUND

Margin status is an important prognostic factor for treating colorectal cancer. This study aimed to investigate the usefulness of a multimodal spectroscopic tissue scanner for real-time cancer diagnosis without tissue staining.

PATIENTS AND METHODS

Diffuse reflectance spectra (DRS) and fluorescence spectra (FS) of < 1-mm-sized paired cancer and normal mucosa tissue were acquired using custom-built spectroscopic tissue scanners. For FS, we analyzed wavelengths and intensities at peaks and highest intensities near (± 1.25 nm) the known fluorescence spectral peaks of collagen (380 nm), reduced nicotinamide adenine dinucleotide (NADH, 460 nm), and flavin adenine dinucleotide (FAD, 550 nm). For DRS, we performed a similar analysis near the peaks of strong absorbers, oxyhemoglobin (oxyHb; 414 nm, 540 nm, and 576 nm) and deoxyhemoglobin (deoxyHb; 432 nm and 556 nm). Logistic regression analysis for these parameters was performed in the testing set.

RESULTS

We acquired 17,735 spectra of cancer tissues and 9438 of normal tissues from 30 patients. Intensity peaks of representative normal spectra for FS and DRS were higher than those of representative cancer spectra. Logistic regression analysis showed wavelength and intensity at peaks, and the intensities of the peak wavelength of NADH, FAD, deoxyHb, and oxyHb had significant coefficients. The area under the receiver operating characteristic curve was 0.927. The scanner had 100%, 64.3%, and 85.3% sensitivity, specificity, and accuracy, respectively.

CONCLUSIONS

The spectroscopic tissue scanner has high sensitivity and accuracy and provides real-time intraoperative resection margin assessments and should be further investigated as an alternative to frozen section.

Prognostic Impact of the Length of the Distal Resection Margin in Rectosigmoid Cancer: An Analysis of the JSCCR Database between 1995 and 2004

Objectives

The necessary and sufficient length of the distal resection margin (l-DRM) for rectosigmoid cancer remains controversial. This study evaluated the validity of the 3-cm l-DRM rule for rectosigmoid cancer in the Japanese classification of colorectal cancer.

Methods

We retrospectively reviewed 1,443 patients with cT3 and cT4 rectosigmoid cancer who underwent R0 resection in Japanese institutions between 1995 and 2004. We identified the optimal cutoff point of the l-DRM affecting overall survival (OS) rate using a multivariate Cox regression analysis model. Using this cutoff point, the patients were divided into two groups after balancing the potential confounding factors of the l-DRM using propensity score matching, and the OS rates of the two groups were compared.

Results

A multivariate Cox regression analysis model revealed that the l-DRM of 4 cm was the best cutoff point with the greatest impact on OS rate (hazard ratio [HR], 1.37; 95% confidence interval [CI], 1.00-1.84; P = 0.0452) and with the lowest Akaike information criterion value. In the matched cohort study, the OS rate of patients who had l-DRM of 4 cm or more was significantly higher than that of patients who had l-DRM < 4 cm (n = 402; 5-year OS rates, 87.6% vs. 80.3%, respectively; HR, 1.60; 95% CI, 1.09-2.31; P = 0.0136).

Conclusions

For cT3 and cT4 rectosigmoid cancer, l-DRM of 4 cm may be an appropriate landmark for a curative intent surgery, and we were unable to definitively confirm the validity of the Japanese 3-cm l-DRM rule.

Oncologic and Perioperative Outcomes of Laparoscopic, Open, and Robotic Approaches for Rectal Cancer Resection: A Multicenter, Propensity Score-Weighted Cohort Study

BACKGROUND

Minimally invasive approaches have been shown to reduce surgical site complications without compromising oncologic outcomes.

OBJECTIVE

The primary aim of this study is to evaluate the rates of successful oncologic resection and postoperative outcomes among laparoscopic, open, and robotic approaches to rectal cancer resection.

DESIGN

This is a multicenter, quasiexperimental cohort study using propensity score weighting.

SETTINGS

Interventions were performed in hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program.

PATIENTS

Adult patients who underwent rectal cancer resection in 2016 were included.

MAIN OUTCOME MEASURES

The primary outcome was a composite variable indicating successful oncologic resection, defined as negative distal and radial margins with at least 12 lymph nodes evaluated.

RESULTS

Among 1028 rectal cancer resections, 206 (20%) were approached laparoscopically, 192 (18.7%) were approached robotically, and 630 (61.3%) were open. After propensity score weighting, there were no significant sociodemographic or preoperative clinical differences among subcohorts. Compared to the laparoscopic approach, open and robotic approaches were associated with a decreased likelihood of successful oncologic resection (ORadj = 0.64; 95% CI, 0.43-0.94 and ORadj = 0.60; 95% CI, 0.37-0.97), and the open approach was associated with an increased likelihood of surgical site complications (ORadj = 2.53; 95% CI, 1.61-3.959). Compared to the laparoscopic approach, the open approach was associated with longer length of stay (6.8 vs 8.6 days, p = 0.002).

LIMITATIONS

This was an observational cohort study using a preexisting clinical data set. Despite adjusted propensity score methodology, unmeasured confounding may contribute to our findings.

CONCLUSIONS

Resections that were approached laparoscopically were more likely to achieve oncologic success. Minimally invasive approaches did not lengthen operative times and provided benefits of reduced surgical site complications and decreased postoperative length of stay. Further studies are needed to clarify clinical outcomes and factors that influence the choice of approach. See Video Abstract at http://links.lww.com/DCR/B70. RESULTADOS ONCOLÓGICOS Y PERIOPERATORIOS DE LOS ABORDAJES LAPAROSCÓPICOS, ABIERTOS Y ROBÓTICOS PARA LA RESECCIÓN DEL CÁNCER RECTAL: UN ESTUDIO DE COHORTE MULTICÉNTRICO Y PONDERADO DEL PUNTAJE DE PROPENSIÓN: Se ha demostrado que los enfoques mínimamente invasivos reducen las complicaciones del sitio quirúrgico sin comprometer los resultados oncológicos.El objetivo principal de este estudio es evaluar las tasas de resección oncológica exitosa y los resultados postoperatorios entre los abordajes laparoscópico, abierto y robótico para la resección del cáncer rectal.Este es un estudio de cohorte cuasi-experimental multicéntrico que utiliza la ponderación de puntaje de propensión.Las intervenciones se realizaron en hospitales que participan en el Programa Nacional de Mejora de la Calidad Quirúrgica del Colegio Americano de Cirujanos.Se incluyeron pacientes adultos que se sometieron a resección de cáncer rectal en 2016.El resultado primario fue una variable compuesta que indicaba una resección oncológica exitosa, definida como márgenes negativos distales y radiales con al menos 12 ganglios linfáticos evaluados.Entre 1,028 resecciones de cáncer rectal, 206 (20%) fueron abordadas por vía laparoscópica, 192 (18.7%) robóticamente y 630 (61.3%) abiertas. Después de ponderar el puntaje de propensión, no hubo diferencias sociodemográficas o clínicas preoperatorias significativas entre las subcohortes. En comparación con el abordaje laparoscópico, los abordajes abiertos y robóticos se asociaron con una menor probabilidad de resección oncológica exitosa (ORadj = 0.64; IC 95%, 0.43-0.94 y ORadj = 0.60; IC 95%, 0.37-0.97), y el abordaje abierto se asoció con una mayor probabilidad de complicaciones del sitio quirúrgico (ORadj = 2.53; IC 95%, 1.61-3.959). En comparación con el abordaje laparoscópico, el abordaje abierto se asoció con una estadía más prolongada (6.8 frente a 8.6 días, p = 0.002).Este fue un estudio de cohorte observacional que utilizó un conjunto de datos clínicos preexistentes. A pesar de la metodología de puntuación de propensión ajustada, la confusión no medida puede contribuir a nuestros hallazgos.Las resecciones que se abordaron por vía laparoscópica tuvieron más probabilidades de lograr el éxito oncológico. Los enfoques mínimamente invasivos no alargaron los tiempos quirúrgicos y proporcionaron beneficios de la reducción de las complicaciones del sitio quirúrgico y la disminución de la duración de la estadía postoperatoria. Se necesitan más estudios para aclarar los resultados clínicos y los factores que influyen en la elección del enfoque. Vea video resumen en http://links.lww.com/DCR/B70.

Survival analysis of local excision vs total mesorectal excision for middle and low rectal cancer in pT1/pT2 stage and intermediate pathological risk

Background

Local excision (LE) is a feasible treatment approach for rectal cancers in stage pT1 and presents low pathological risk, whereas total mesorectal excision (TME) is a reasonable treatment for more advanced cancers. On the basis of the pathology findings, surgeons may suggest TME for patients receiving LE. This study compared the survival outcomes between LE with/without chemoradiation and TME in mid and low rectal cancer patients in stage pT1/pT2, with highly selective intermediate pathological risk.

Methods

This retrospective study included 134 patients who received TME and 39 patients who underwent LE for the treatment of intermediate risk (pT1 with poor differentiation, lymphovascular invasion, perineural invasion, relatively large tumor, or small-sized pT2 tumor) rectal cancer between 1998 and 2016.

Results

Overall survival (OS), disease-free survival (DFS), and cumulative recurrence rate (CRR) were similar between the LE (3-year DFS 92%) and TME (3-year DFS 91%) groups. Following subgrouping into an LE with adjuvant therapy group and a TME without adjuvant therapy group, the compared survival outcomes (OS, DFS, and CRR) were found not to be statistically different. The temporary and permanent ostomy rates were higher in the TME group than in the LE group (p < 0.001). Rates of early and late morbidity following surgery were higher in the TME group (p = 0.005), and LE had similar survival compared with TME.

Conclusion

For patients who had mid and low rectal cancer in stage pT1/pT2 and intermediate pathological risk, LE with chemoradiation presents an alternative treatment option for selected patients.

Factors predicting recurrence after curative resection for rectal cancer: a 16-year study

BACKGROUND

The recurrence after curative surgery of the rectal adenocarcinoma is a serious complication, considered as a failure of the therapeutic strategy. The aim of this study was to identify the different prognostic factors affecting the recurrence of adenocarcinoma of the rectum.

METHODS

A retrospective analysis of patients operated for adenocarcinoma of the rectum between January 2000 and December 2015 was conducted. The study of the recurrence rate and prognostic factors was performed through the Kaplan Meier survival curve and the Cox regression analysis.

RESULTS

During the study period, 188 patients underwent curative surgery for rectal adenocarcinoma, among which 53 had a recurrence. The recurrence rate was 44.6% at 5 years. The multivariate analysis identified four parameters independently associated with the risk of recurrence after curative surgery: a distal margin ≤ 2 cm (HR = 6.8, 95% CI 2.7-16.6, 6), extracapsular invasion of lymph node metastasis (HR = 4.4, 95% CI 1.3-14), tumor stenosis (HR = 4.3, 95% CI 1.2-15.2), and parietal invasion (pT3/T4 disease) (HR = 3, 95% CI 1.1-9.4).

CONCLUSION

The determination of the prognostic factors affecting the recurrence of rectal adenocarcinoma after curative surgery allows us to define the high-risk patients for recurrence.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03899870 . Registered on 2 February 2019, retrospectively registered.

Impact of Length of Distal Margin on Outcomes Following Sphincter Preserving Surgery for Middle and Lower Third Rectal Cancers

Outcomes of sphincter preserving surgery for distal rectal cancers improve with clear circumferential resection and distal resection margin. However, the extent of distal resection margin after a complete mesorectal excision is often a cause for debate. We evaluated the outcome of middle and lower third rectal cancer patients undergoing sphincter preservation with variable distal resection margin at our center. Patients with biopsy-proven rectal adenocarcinoma within 10 cm from anal verge undergoing sphincter preserving resections were included. Patients with positive circumferential resection margin were excluded. Patients were divided into three groups based on the extent of distal resection margin (< 6 mm, 6-10 mm, > 10 mm) and oncological outcomes were compared. The median age of 242 patients was 50 years and 44 (18.2%) were high-grade tumors. Preoperative chemoradiation was used in 185 (75.2%) patients. Median distal resection margin was 20 mm. Patients in < 10 mm group had a significantly higher proportion of lower third (68.3% vs 39.8%, p = 0.004) and chemoradiation-treated tumors (85.4 vs 74.6%, p = 0.001). A significantly higher percentage required an intersphincteric resection in the < 10 mm group (53.7% vs 14.4%, p = 0.0001). Significantly higher percentage tumors were pT3 in > 10 mm group (45.3% vs. 31.7%) (p = 0.05). The median follow-up was 23 months. There was no difference in the overall, loco-regional, and distant recurrence rates between the three groups. A subcentimeter distal resection margin does not influence loco-regional or distant recurrence rates following sphincter preserving surgery for middle and lower third rectal adenocarcinoma.

Routine splenic flexure mobilization may increase compliance with pathological quality metrics in patients undergoing low anterior resection

AIM

Mandatory splenic flexure mobilization (SFM) has been debated for rectal cancers. Proponents argue that additional mobilization facilitates a tension-free anastomosis; however, this must be weighed against heightened morbidity. Little is known about the impact of specific techniques on pathology quality metrics. We aim to determine the impact of SFM on pathology quality metrics for patients undergoing rectal resections for colorectal adenocarcinoma.

METHOD

Patients were selected by querying the University of Kansas electronic medical records and the American College of Surgeons National Surgical Quality Improvement Program database based on Current Procedural Terminology codes. Patients were categorized as SFM or non-SFM. Primary outcomes were node yield less than 12 and margin length.

RESULTS

There were 146 patients who met the inclusion criteria for chart review and 7369 included from the national database. Splenic flexure mobilization was associated with wider margins (3.52 vs 2.51 cm in low anterior resection, P < 0.01) and a decreased rate of inadequate nodal staging in patients undergoing low anterior resection (3.7% vs 19.3% P < 0.01).

CONCLUSIONS

SFM may affect surgical quality metrics in patients undergoing resection for distal colon and rectal adenocarcinoma. Further study is warranted to determine whether these differences in quality and pathology translate into differences in oncological outcomes.

Image-guided surgery in cancer: A strategy to reduce incidence of positive surgical margins

Primary treatment for many solid cancers includes surgical excision or radiation therapy, with or without the use of adjuvant therapy. This can include the addition of radiation and chemotherapy after primary surgical therapy, or the addition of chemotherapy and salvage surgery to primary radiation therapy. Both primary therapies, surgery and radiation, require precise anatomic localization of tumor. If tumor is not targeted adequately with initial treatment, disease recurrence may ensue, and if targeting is too broad, unnecessary morbidity may occur to nearby structures or remaining normal tissue. Fluorescence imaging using intraoperative contrast agents is a rapidly growing field for improving visualization in cancer surgery to facilitate resection in order to obtain negative margins. There are multiple strategies for tumor visualization based on antibodies against surface markers or ligands for receptors preferentially expressed in cancer. In this article, we review the incidence and clinical implications of positive surgical margins for some of the most common solid tumors. Within this context, we present the ongoing clinical and preclinical studies focused on the use of intraoperative contrast agents to improve surgical margins. This article is categorized under: Laboratory Methods and Technologies > Imaging.

A Distal Resection Margin of ≤1 mm and Rectal Cancer Recurrence After Sphincter-Preserving Surgery: The Role of a Positive Distal Margin in Rectal Cancer Surgery

BACKGROUND

There is little information about the prognostic value of a microscopically positive distal margin in patients who have rectal cancer.

OBJECTIVE

We aimed to investigate the influence of a distal margin of ≤1 mm on oncologic outcomes after sphincter-preserving resection for rectal cancer.

DESIGN

This is a retrospective cohort study.

SETTINGS

The study was conducted at 2 hospitals.

PATIENTS

A total of 6574 patients underwent anterior resection for rectal cancer from January 1999 to December 2014; 97 (1.5%) patients with a distal margin of ≤1 mm were included in this study. For comparative analyses, patients were matched with 194 patients with a negative distal margin (>1 mm) according to sex, age, BMI, ASA score, neoadjuvant treatment, tumor location, and stage.

MAIN OUTCOME MEASURES

The oncologic outcomes of the 2 groups were compared.

RESULTS

Perineural and lymphovascular invasion rates were significantly higher in patients with a positive distal margin (54.6% vs 28.9%; 67.0% vs 42.8%; both p < 0.001) compared with to patients with negative distal margin. Comparison between microscopically positive and negative distal margin showed worse oncologic outcomes in patients with a microscopically positive distal margin, including 5-year local recurrence rate (24.1% vs 12.0%, p = 0.005); 5-year distant recurrence rate (35.5% vs 20.2%, p = 0.011); 5-year disease-free survival (45.5% vs 69.5%, p < 0.001); and 5-year OS (69.2% vs 79.7%, p = 0.004). Among the 97 patients with a microscopically positive distal margin, the 5-year disease-free survival rate was higher in patients who received adjuvant therapy (52.0% vs 30.7%, p = 0.089).

LIMITATIONS

This is a retrospective study; bias may exist.

CONCLUSIONS

A distal margin of 1 mm is associated with worse oncologic results. Our data indicate the importance of achieving a clear distal margin in the surgical treatment of rectal cancer. Adjuvant therapy should be used in these patients to reduce recurrence. See Video Abstract at http://links.lww.com/DCR/A408.

Outcomes of patients with abdominoperineal resection (APR) and low anterior resection (LAR) who had very low rectal cancer

We compared the oncological outcomes of sphincter-saving resection (SSR) and abdominoperineal resection (APR) in 409 consecutive patients with very low rectal cancer (i.e., tumors within 3 cm from the anal verge); 335 (81.9%) patients underwent APR and 74 (18.1%) underwent SSR. The APR group comprised higher proportions of men (67.5% vs 55.4%, P = .049) and advanced-stage patients (P < .001). Preoperative chemoradiotherapy (PCRT) was more frequently administered in the SSR group (83.8% vs 52.8%, P < .001). Overall, the systemic and local recurrence rates were 29.1% and 6.1%, respectively. On stratification according to PCRT and pathologic stage, the mode of surgery did not affect the recurrence type. Moreover, recurrence-free survival (RFS) did not differ according to the mode of surgery in different cancer stages. RFS was associated with ypT and ypN stages in patients who received PCRT, while pN stage, lymphovascular invasion (LVI), and circumferential resection margin (CRM) involvement were risk factors for RFS in those who did not receive PCRT. Notably, SSR was not found to be a risk factor for RFS in either subgroup. Patients who were stratified according to cancer stage and PCRT also showed no differences in RFS according to the mode of surgery. Our results demonstrate that, regardless of PCRT administration, SSR is an effective treatment for very low rectal cancer, while CRM is an important prognostic factor for patients who did not receive PCRT.

Continuous Effect of Radial Resection Margin on Recurrence and Survival in Rectal Cancer Patients Who Receive Preoperative Chemoradiation and Curative Surgery: A Multicenter Retrospective Analysis

PURPOSE

To elucidate the proper length and prognostic value of resection margins in rectal cancer patients who received preoperative chemoradiotherapy (CRT) followed by curative total mesorectal excision (TME).

METHODS AND MATERIALS

A total of 1476 rectal cancer patients staging cT3-4N0-2M0 were analyzed. All patients received radiation dose of 50.4 Gy in 28 fractions with concurrent 5-fluorouracil or capecitabine. Total mesorectal excision was performed 4 to 8 weeks after radiation therapy.

RESULTS

The recurrence-free survival (RFS) at 5 years showed a significant difference between 3 groups: patients with circumferential resection margin (CRM) ≤1 mm, CRM 1.1 to 5 mm, and CRM >5 mm (46.2% vs 68.6% vs 77.5%, P<.001). Patients with CRM ≤1 mm showed a significantly higher cumulative incidence of locoregional recurrence (P<.001) and distant metastasis (P<.001) at 5 years compared with the other 2 groups. Patients with CRM 1.1 to 5 mm showed a significantly higher cumulative incidence of distant metastasis (P<.001), but not locoregional recurrence (P=.192), compared with those with CRM >5 mm. Distal resection margin (≤5 vs >5 mm) did not show any significant difference in cumulative incidence of locoregional recurrence (P=.310) and distant metastasis (P=.926).

CONCLUSION

Rectal cancer patients with CRM ≤1 mm are a high-risk group, with the lowest RFS. Patients with CRM 1.1 to 5 mm may be at intermediate risk, with moderately increased distant recurrence. Distal resection margin was not significantly associated with RFS in rectal cancer after neoadjuvant CRT and total mesorectal excision.

Colorectal surgery in Italy. Criteria to identify the hospital units and the tertiary referral centers entitled to perform it

Improving the quality and effectiveness of care is a key priority of any health policy. The outcomes of health care can be considered as indicators of effectiveness or quality. The scientific literature that evaluates the association between the volume of activity and the outcome of health interventions has greatly developed over the past decade, but, for practical reasons, ethical and social issues, a few randomized controlled studies were made to evaluate this association, although there are numerous observational studies of outcome and systematic reviews of the studies themselves. The colorectal surgery is the most studied area and it represents the ideal testing ground to determine the effectiveness of the quality indicators because of the high incidence of the disease and the wide spread in the territory of the structures that aim to tackle these issues. Numerous studies have documented an association between the large number of colo-rectal surgical procedures and the quality of results. In particular, the volume of activity is one of the characteristics of measurable process that can have a significant impact on the outcome of health care. In conclusion, the ability to use volume thresholds as a proxy for quality is very tempting but it is only part of reality. Infact, the volume-outcome relationship strictly depends on the type of cancer (colon vs rectum) and it appears somehow stronger for the individual surgeon than for the hospital; especially for the 5-year overall survival, operative mortality and number of permanent stoma.

Role of intraoperative frozen section for assessing distal resection margin after anterior resection

BACKGROUND AND AIMS

The use of neoadjuvant long-course chemoradiotherapy (LCRT), shorter distal safety margins (DSMs) and stapled or intersphincteric resections has increased sphincter preservation rates. While intraoperative frozen section (IOFS) is not mandatory, it helps achieve negative distal resection margins (DRMs). Our aim was to audit the role of IOFS for DRM assessment while performing sphincter-saving rectal surgery and to identify those subgroups that would benefit the most from IOFS analysis.

METHODS

Patients who underwent rectal cancer surgery between 2009 and 2013 were identified from a prospectively maintained database. Patients who intraoperatively underwent an IOFS for DRM assessment were included in the study. Factors associated with a positive margin on IOFS were analysed. The sensitivity and specificity of IOFS were also assessed.

RESULTS

Of 250 patients, who had an anterior resection with an IOFS, 12 had an involved DRM. Of these patients, eight were involved by adenocarcinoma, two by acellular mucin, one by moderate dysplasia and one by adenoma confirmed on paraffin section. Positive margins had a 100 % intervention rate. There were two false negative on IOFS. IOFS had a sensitivity of 85.17 % with a specificity of 100 % and a negative predictive value of 99.16 %. Specimens with a positive IOFS were lower rectal (P < 0.05), poorly differentiated and post LCRT locally advanced tumours.

CONCLUSIONS

IOFS to confirm negative DRM is recommended in lower rectal tumours irrespective of DSM. It can be considered for locally advanced post LCRT poorly differentiated mid rectal tumours and avoided for upper rectal tumours.

Sphincter-sparing surgery in patients with low-lying rectal cancer: techniques, oncologic outcomes, and functional results

BACKGROUND

Rectal cancer management has evolved into a complex multimodality approach with survival, local recurrence, and quality of life parameters being the relevant endpoints. Surgical treatment for low rectal cancer has changed dramatically over the past 100 years.

DISCUSSION

Abdominoperineal resection, once the standard of care for all rectal cancers, has become much less frequently utilized as surgeons devise and test new techniques for preserving the sphincters, maintaining continuity, and performing oncologically sound ultra-low anterior or local resections. Progress in rectal cancer surgery has been driven by improved understanding of the anatomy and pathophysiology of the disease, innovative surgical technique, improved technology, multimodality approaches, and increased appreciation of the patient's quality of life. The patient with a low rectal cancer, once almost universally destined for impotence and a colostomy, now has the real potential for improved survival, avoidance of a permanent stoma, and preservation of the normal route of defecation.

Oncologically safe distal resection margins in rectal cancer patients treated with chemoradiotherapy

INTRODUCTION

Although current guidelines recommend distal resection margins (DRM) of 2-5 cm in rectal cancer operation, smaller margins may be safe. We therefore assessed the impact of distal margins on outcomes in patients with rectal cancer treated with neoadjuvant chemoradiotherapy (CRT) followed by radical resection or resection followed by adjuvant CRT.

MATERIALS AND METHODS

This study involved 376 patients who underwent sphincter-saving resection for rectal adenocarcinoma and pre- or postoperative CRT between 2000 and 2006. DRMs were measured on pinned fixed specimens. We excluded patients who did not complete planned CRT and those with stage IV disease. A retrospective cross-sectional analysis was performed.

RESULTS

No significant differences in local recurrence (9.8 versus 7.3%; P = 0.324) and systemic recurrence (16.4 versus 18.7%; P = 0.731) were observed in patients with DRMs of ≤5 and >5 mm, respectively. Moreover, in each DRM category, there were no differences in local and systemic recurrence rates between patients who received pre- or postoperative CRT. DRM did not affect overall survival (P = 0.880) or 5-year survival rate (80.3 versus76.8%; P = 0.340).

CONCLUSION

A distal margin of at least 5 mm with negative resection margin on frozen section does not reduce oncological safety in rectal cancer patients who receive pre- or postoperative CRT.

What is a safe distal resection margin in rectal cancer patients treated by low anterior resection without preoperative radiotherapy?

AIM

The aim of this study was to examine what constitutes an acceptable distal resection margin (DRM) when performing sphincter-saving surgery for rectal cancer without preoperative radiotherapy.

METHOD

This national study consisted of 3571 patients for whom information on DRM was available and who were radically treated by anterior resection between 1993 and 2004. Of these, 3342 (93.5%) patients had not received preoperative radiotherapy. The DRM was measured on fixed specimens.

RESULTS

The 5-year local recurrence rate was 14.5% for patients with a DRM of 0-10 mm compared to 9.6% for patients with a DRM of 11-20 mm, 8.9% for a DRM of 21-30 mm, 7.0% for a DRM of 31-40 mm, 7.7% for a DRM of 41-50 mm and 8.7% for a DRM of > 50 mm. After adjustment for other independent prognostic factors, a DRM of 0-10 mm was found to have significant impact on local recurrence. The DRM had no impact on distant metastases or overall survival.

CONCLUSION

For rectal cancer patients treated without radiotherapy, a DRM of > 10 mm is recommended.

Risk of permanent stoma after resection of rectal cancer depending on the distance between the tumour lower edge and anal verge

The distance between the anal verge and lower edge of rectal cancer is one of the most important factors affecting the feasibility of sphincter-preserving resection.The aim of the study was to assess the risk of permanent stoma after resection of rectal tumour depending on the distance between the tumour and the anal verge.Material and methods. The retrospective analysis covered 884 patients after resection of rectal cancer. The distance between the anal verge and the lowest edge of the tumour was measured during endoscopic examination. Surgical technique was similar in all cases. For statistical analysis, the chi-square test and Fisher exact test were used.Results. The overall rate of sphincter-preserving procedures was 71.8%, 90.1% of which were anterior resections. The greatest differences between the rate of anterior resections were noted for the segment between the 4th and the 5th centimetres: 30.1% for 4 cm vs 66.7% for 5 cm, p = 0.005. Overall, in 328 patients (37.1%) surgical treatment resulted in a permanent stoma. The number included: 246 (75.0%) patients after abdominosacral resection, 44 (13.4%) patients after the Hartmann procedure, three (0.9%) patients after proctocolectomy, and 28 (8.5%) patients after anterior resection, with a permanent stoma as a result of anastomotic leak. The overall rate of anastomotic leak was 11.7%. Formation of a defunctioning stoma in patients with a low-lying (6 cm from the anal verge) tumour reduced the risk of symptomatic anastomotic leak: 6.3% vs 20.5%; p = 0.049.Conclusions. Anterior resection of tumours located 6 cm from the anal verge is feasible in 90%. Anastomotic leak that requires reoperation increases the risk of permanent colostomy. In selected cases, formation of a defunctioning stoma after resection of low-lying rectal cancer can reduce the risk of permanent colostomy.

Acceptance of a 5-mm distal bowel resection margin for rectal cancer: is it safe?

AIM

Acceptance of a short distal bowel margin results in a higher rate of anterior resection but may compromise oncological safety. This study aimed to evaluate the safety of a 5-mm distal margin.

METHOD

A retrospective analysis was carried out of 412 consecutive patients with rectal cancer treated with anterior resection with a negative circumferential resection margin. Radiotherapy was given to 63% of patients with an advanced tumour. The median follow up was 75 months.

RESULTS

Fewer patients in the group with a distal margin of ≤ 5 mm had a tumour with an advanced pT stage compared to patients in the group with a distal margin of > 5 mm (P = 0.033). Two patients were converted to abdominoperineal resection because of a positive 'doughnut', leaving 410 patients, in whom 5.4% (95% CI, 0-11.3%) of the group with a distal margin of ≤ 5 mm had local recurrence at 5 years compared with 4.2% (95% CI, 2.1-6.3%) of the group with a distal margin of > 5 mm (P = 0.726). The corresponding figures for the 5-year overall survival were 82.4% (95% CI, 72.6-92.2%) vs 76.3% (95% CI, 71.8-80.8%) (P = 0.581). All four anastomotic recurrences occurred in the group with a distal margin of > 5 mm.

CONCLUSION

A distal margin of ≤ 5 mm did not compromise oncological safety in patients undergoing preoperative radiation for an advanced rectal cancer.

Laparoscopic low anterior resection and transanal pull-through for low rectal cancer: a Natural Orifice Specimen Extraction (NOSE) technique

Ultralow anterior resection with coloanal anastomosis has been proven to be oncologically sound and the majority of patients will have acceptable functional outcome. Here we describe a technique that combines laparoscopic ultralow total mesorectal excision with an intersphincteric dissection in order to allow the mobilized rectum and descending colon to be extracted via the muscular anal canal and so avoid any further abdominal incision other than laparoscopic port sites. We believe this novel approach to have significant clinical potential in selected patients.

Optimal use of adjuvant chemotherapy in stage II colorectal cancer

BACKGROUND AND OBJECTIVE

The prognosis of stage II colorectal cancer varies. Whether or not to perform adjuvant chemotherapy on patients with stage II colorectal cancer is a controversial issue. The aims of this study were to identify relevant risk factors for the prognosis of stage II colorectal cancer and to evaluate the need for adjuvant chemotherapy.

METHOD

Between January 2000 and January 2005, 443 patients with stage II colorectal cancer who had received radical surgery at the Sun Yat-sen University Cancer Center were retrospectively analyzed. The overall survival rates and survival curves were analyzed using the Kaplan-Meier method and log-rank test. Univariate and multivariate prognostic analyses were performed using the Cox regression model. Patients with certain important risk factors were analyzed according to whether they received adjuvant chemotherapy, and four chemotherapeutic regimens were classified into sub-groups and analyzed.

RESULTS

Univariate analyses showed that intestinal obstruction or perforation, type 2 diabetes mellitus, an inadequate surgical margin, and sampling of less than 12 lymph nodes were risk factors that correlated with poor prognosis. Patients with an intestinal obstruction or perforation and insufficient lymph node samples achieved higher 5-year survival rates with adjuvant chemotherapy than with surgery alone.

CONCLUSION

Intestinal obstruction or perforation, sampling of less than 12 lymph nodes, and inadequate surgical margins were identified as risk factors for poor survival, and patients with either of the first two factors benefited from adjuvant chemotherapy. Moreover, the use of capecitabine alone may be insufficient for patients with an intestinal obstruction or perforation.

Adequate length of the distal resection margin in rectal cancer: from the oncological point of view

INTRODUCTION

The distal resection margin (DRM) has been considered an important factor for the oncological outcome of rectal cancer surgery. However, the optimal distal margins required to achieve safe oncological outcome remains to be controversial.

MATERIAL AND METHODS

More recently, as circumferential resection margin or mesorectal margin has been additionally reported to be more important factors predicting patient outcome than the distal mucosal margin, a re-evaluation of the impact of DRM on patient outcome is needed.

RESULTS

The extent of distal tumor spread is known to be influenced by a variety of factors such as tumor location, lymph node metastasis, and tumor size. DRM might affect survival more than a local recurrence. Because distal intramural tumor spread rarely exceeds 1 to 2 cm in most rectal cancers, and local control and survival do not seem to be compromised by shorter distal resection margins, the generally accepted practice is to aim for a 2-cm DRM. However, in the recent trend of curative resection after preoperative chemoradiotherapy, with an otherwise favorable tumor such as well-differentiated tumor and no lymph node metastasis, a DRM at < or =1 cm does not necessarily portend a poor prognosis. In cases with preoperative chemoradiotherapy, distal resection margins need to be evaluated individually.

DISCUSSION

It has been suggested that down-staging of low-lying rectal cancers after preoperative radiation might well include the pathological clearance of distal intramural microscopic spread. Moreover, the measurement of DRM varies with respective study, making it difficult to compare.

CONCLUSION

We need an applicable intraoperative method to accurately measure distal resection margin, enabling comparative outcome.

Colorectal cancer stem cells

PURPOSE

The cancer stem cell hypothesis predicts that only a subpopulation of cells within a tumor is responsible for driving growth. If this hypothesis were true, it would have a significant impact on our current treatment of cancer because conventional chemotherapy and radiotherapy target rapidly proliferating cells making up the bulk of the tumor, not specifically cancer stem cells. The aims of this review are to highlight the current evidence supporting the existence of cancer stem cells in colorectal cancer, to consider the relative merits of current cancer stem cell markers, and to discuss the implications of this on our current treatment of cancer.

METHODS

Published scientific articles were selected by searching the PubMed database by use of the terms "colorectal," "cancer," and "stem cells," and by use of the bibliographies of extracted articles.

RESULTS AND CONCLUSION

CD133, a glycosylated cell surface protein, has been demonstrated to isolate for a subpopulation of colorectal tumor cells enriched in cancer stem cells. However, only 1 in 262 CD133+ cells are able to initiate tumors. Other cancer stem cell markers have been investigated, but an overall need exists to identify more specific markers to allow further characterization of these cancer stem cells. We discuss how increased understanding of the distribution and behavior of cancer stem cells within tumors could have significant implications for the management of colorectal cancer, including screening, resection margins, sentinel node biopsy, determination of prognosis, and the development of novel therapeutic targets.

Proliferating cell nuclear antigen as a prognostic factor after total mesorectal excision of stage II-III rectal cancer

BACKGROUND

Proliferating cell nuclear antigen (PCNA) is an auxiliary protein of DNA polymerase delta that is tightly associated with sites of DNA replication; whether PCNA is a definite prognostic factor remains controversial. This study determined the clinicopathological factors associated with the long-term oncological outcome after radical resection of stage II-III rectal cancer, focusing on PCNA.

METHODS

We retrospectively reviewed 135 consecutive patients who underwent curative surgery for stage II-III rectal cancer between August 2001 and April 2004. Prognostic factors including immunohistochemical PCNA expression and the clinical outcome were evaluated.

RESULTS

The PCNA index correlated with lymph node metastasis (P = 0.010). A multivariate analysis identified two independent factors that significantly affected both disease-free and overall survival: lymph node metastasis and PCNA index. With a median follow-up period of 60 months (range 8-87 months), both 5-year disease-free and overall survival of the low PCNA group were significantly higher than those of the high PCNA group (71.8% versus 32.0%, P < 0.001; 83.9% versus 50.0%, P < 0.001, respectively).

CONCLUSION

For patients undergoing curative resection for rectal cancer, pathological N stage and high PCNA expression can provide valuable prognostic information about survival. This study suggests that the PCNA index may be used as an independent prognostic factor in stage II-III rectal cancer patients.