Relationship between pathologic T-stage and nodal metastasis after preoperative chemoradiotherapy for locally advanced rectal cancer

Association of clinicopathological factor with lymph node metastasis in rectal cancer patients: a retrospective cohort study

INTRODUCTION

Systemic inflammatory response (SIR) indicators serve as predictive factors for lymph node metastasis (LNM) in various cancers. This study aimed to investigate the association of platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) with LNM in rectal cancer and to identify clinicopathological factors linked to LNM.

METHODS

We retrospectively analyzed 181 rectal cancer patients who underwent surgical resection. Preoperative NLR and PLR were calculated from blood samples, with optimal cutoff values determined by receiver operating characteristic (ROC) analysis. Associations between NLR/PLR and clinicopathological features were evaluated, risk factors for LNM were analyzed via univariate and multivariate logistic regression.

RESULTS

No significant differences were observed between the high NLR (H-NLR) and low NLR (L-NLR) groups in terms of clinicopathological characteristics, including TNM stage, perineural invasion (PNI), lymphovascular invasion (LVI), or serum levels of CEA and CA19-9 respectively (p > 0.05).In contrast, the high PLR (H-PLR) group showed significantly higher prevalence of several adverse pathological features: The H-PLR group had a higher positive PNI (54.2% vs.25.0%,p = 0.04), greater positive LVI(51.6% vs.28.6%,p = 0.025),and more positive TDs (14.4% vs.0,p = 0.028), increased lymph node metastasis (52.9% vs.17.9%,p < 0.001), more elevated CEA (43.1% vs.14.3%,p = 0.005) and more advanced tumor stage (stage II + stage III,81% vs.67.9%,p = 0.003).Univariate analysis identified several factors significantly associated with LNM: T stage (OR = 3.156, 95%CI:1.580-6.303),positive PNI (OR = 6.182,95%CI:3.242-11.787),positive LVI (OR = 10.271,95%CI:5.177-20.375),H-PLR(OR = 5.175,95%CI:1.870-14.321),positive TDs (OR = 3.390,95%CI:1.261-9.117),TLN(OR = 1.053,95%CI:1.005-1.103),elevated CEA(OR = 3.313,95%CI:1.655-5.920) and elevated CA199 (OR = 2.248,95%CI:1.012-4.992) were correlated with LNM using univariate analysis, but only positive LVI(adjusted OR = 6.203,95%CI:2.892-13.303,p < 0.001) and positive PNI (adjusted OR = 3.086,95%CI:1.341-7.102,p = 0.008) were the independent risk factors for LNM using multivariate analysis.

CONCLUSION

H-PLR but not H-NLR may be associated with LNM, positive LVI and PNI were independent risk factors for LNM in RC.

Factors associated with pathological complete remission after neoadjuvant chemoradiotherapy in locally advanced rectal cancer: a real-world clinical setting

Objective

This study aims to identify factors associated with achieving a pathological complete remission (pCR) in patients with locally advanced rectal cancer (LARC) after neoadjuvant chemoradiotherapy (nCRT).

Methods

We conducted a cohort analysis of 171 LARC patients who underwent curative resection post-nCRT at the First Affiliated Hospital of Guangxi Medical University between January 2015 and December 2021. The data encompassed clinical and pathological information. Univariate and binary logistic regression multivariate analyses were employed to examine the factors influencing pCR achievement after nCRT. Kappa value tests were utilized to compare clinical staging after nCRT with postoperative pathological staging.

Results

Postoperative histopathology revealed that of the 171 patients, 40 (23.4%) achieved TRG 0 grade (pCR group), while 131 (76.6%) did not achieve pCR, comprising 36 TRG1, 42 TRG2, and 53 TRG3 cases. Univariate analysis indicated that younger age (p=0.008), reduced tumor occupation of intestinal circumference (p =0.008), specific pathological types (p=0.011), and lower pre-nCRT CEA levels (p=0.003) correlated with pCR attainment. Multivariate analysis identified these factors as independent predictors of pCR: younger age (OR=0.946, p=0.004), smaller tumor occupation of intestinal circumference (OR=2.809, p=0.046), non-mucinous adenocarcinoma pathological type (OR=10.405, p=0.029), and lower pre-nCRT serum CEA levels (OR=2.463, p=0.031). Clinical re-staging post-nCRT compared to postoperative pathological staging showed inconsistent MRI T staging (Kappa=0.012, p=0.718, consistency rate: 35.1%) and marginally consistent MRI N staging (Kappa=0.205, p=0.001, consistency rate: 59.6%).

Conclusion

LARC patients with younger age, presenting with smaller tumor circumferences in the intestinal lumen, lower pre-nCRT serum CEA levels, and non-mucinous adenocarcinoma are more likely to achieve pCR after nCRT. The study highlights the need for improved accuracy in clinical re-staging assessments after nCRT in LARC.

Completion total mesorectal excision after neoadjuvant radiochemotherapy and local excision for rectal cancer

AIM

Local excision (LE) in selected cases after neoadjuvant radiochemotherapy (RCT) for locally advanced rectal cancer in clinically complete or major responders has been recently reported as an alternative to standard radical resection. Completion total mesorectal excision (cTME) is generally performed when high-risk pathological features are found in LE surgical specimens. The aim of this study was to evaluate the incidence of residual tumour and lymph node metastases after cTME in patients previously treated by RCT + LE. The secondary aims were to quantify the rate of postoperative morbidity and mortality and to evaluate the long-term oncological outcome of this group of patients.

METHODS

All patients treated from 2007 to 2020 by LE for locally advanced rectal cancer with a clinically complete or major response to RCT who had a subsequent cTME for high-risk pathological factors (ypT >1 and/or TRG >2 and/or positive margins) were included in this multicentre retrospective study. Pathological data, postoperative short-term morbidity (classified according to Clavien-Dindo) and mortality and oncological long-term outcome after cTME were recorded in a database. Statistical analysis was performed using Wizard for iOS version 1.9.31.

RESULTS

A total of 47 patients were included in the study. The rate of R0 resection was 95.7%, and a sphincter-saving procedure was performed in 37 patients (78.7%), with a protective stoma rate of 78.4%. In 28 cases (59.6%), it was possible to perform a minimally invasive approach. A residual tumour (pT and/or pN) on cTME specimens was found in 21 cases (44.7%). The rate of lymph node metastases was 12.8%. The overall short-term (within 30 days) postoperative morbidity was 34%, but grade >2 postoperative complications occurred in only nine patients (19.1%), with a reoperation rate of 6.4%. No short-term postoperative deaths occurred. At a median follow-up of 57 months (range: 21-174), the long-term stoma-free rate was 70.2%, and the actuarial 5-year overall survival (OS), disease-free survival (DFS) and local control (LC) were 86.7%, 88.9% and 95.7%, respectively.

CONCLUSION

When patients exhibit high-risk pathological factors after RCT + LE, cTME should be suggested due to the high risk of residual tumour or lymph node involvement (44.7%). The results after cTME in terms of the rate of R0 resection, sphincter-saving procedure, postoperative morbidity and mortality and long-term oncological outcome seem to be acceptable and do not represent a contraindication to use LE as a first-step treatment in patients with major or complete clinical response after RCT.

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

Background:

Depth of tumor is a risk factor for lymph node metastasis in rectal cancer, but impact of yield pathologic T (ypT) stage on lymph node involvement in rectal cancer remains unclear. The aim of this study was to evaluate the correlation between ypT stage and lymph node metastasis.

Methods:

From January 2010 to December 2015, 602 patients who were diagnosed with rectal cancer and treated with neoadjuvant chemoradiotherapy (CRT) followed by radical operation were reviewed retrospectively. The correlations between ypT stage and lymph node status and survival were evaluated.

Results:

On pathology, 179 (29.7%) patients exhibited regional lymph node metastasis. Lymph node metastasis was seen in 8.5% of ypT0 patients, 20% of ypT1, 18.4% of ypT2, 47.5% of ypT3, and 27.3% of ypT4. Positive lymph node metastasis was correlated with ypT stage. In addition, the difference of lymph node metastasis in ypT stage subgroups was statistically significant (p < 0.001). Five-year disease-free survival was significantly different in the ypT stage subgroups (88.7% versus 86.7% versus 82.6% versus 64.7% versus 72.7%, p < 0.001), as was 5-year overall survival (96.2% versus 90.0% versus 95.8% versus 80.0% versus 90.9%, p < 0.001).

Conclusion:

YpT stage is associated with lymph node metastasis in rectal cancer treated with neoadjuvant CRT and radical operation, and ypT0 patients exhibited an 8.5% lymph node metastasis rate. Therefore, the decision for local excision or the watch-and-wait strategy for rectal cancer treated with neoadjuvant CRT and predicted to show a pathologic complete response should be considered with caution.

Rectal Sparing Approach After Neoadjuvant Therapy in Patients with Rectal Cancer: The Preliminary Results of the ReSARCh Trial

BACKGROUND

Rectum-preservation for locally advanced rectal cancer has been proposed as an alternative to total mesorectal excision (TME) in patients with major (mCR) or complete clinical response (cCR) after neoadjuvant therapy. The purpose of this study was to report on the short-term outcomes of ReSARCh (Rectal Sparing Approach after preoperative Radio- and/or Chemotherapy) trial, which is a prospective, multicenter, observational trial that investigated the role of transanal local excision (LE) and watch-and-wait (WW) as integrated approaches after neoadjuvant therapy for rectal cancer.

METHODS

Patients with mid-low rectal cancer who achieved mCR or cCR after neoadjuvant therapy and were fit for major surgery were enrolled. Clinical response was evaluated at 8 and 12 weeks after completion of chemoradiotherapy. Treatment approach, incidence, and reasons for subsequent TME were recorded.

RESULTS

From 2016 to 2019, 160 patients were enrolled; mCR or cCR at 12 weeks was achieved in 64 and 96 of patients, respectively. Overall, 98 patients were managed with LE and 62 with WW. In the LE group, Clavien-Dindo 3+ complications occurred in three patients. The rate of cCR increased from 8- to 12-week restaging. Thirty-three (94.3%) of 35 patients with cCR had ypT0-1 tumor. At a median 24 months follow-up, a tumor regrowth was found in 15 (24.2%) patients undergoing WW.

CONCLUSIONS

LE for patients achieving cCR or mCR is safe. A 12-week interval from chemoradiotherapy completion to LE is correlated with an increased cCR rate. The risk of ypT > is reduced when LE is performed after cCR.

Low rectal cancer treatment strategies: a cohort study assessing watch and wait

PURPOSE

Treatment strategies for low rectal cancer have been evolving toward achieving less treatment morbidity with the same oncological success-we aimed to assess the results of the new watch and wait (W&W) strategy in our cohort.

METHODS

A tertiary care cohort study was conducted. New patients with rectal adenocarcinoma up to 6 cm from the anal margin, cM0, locally staged higher than cT1N0, evaluated between November 2014 and October 2018, were included. All 93 patients received neoadjuvant radiotherapy ± chemotherapy. Re-evaluation was planned 8-12 weeks after the end of treatment. Patients showing clinical complete response (cCR) were given the choice of either to proceed to surgery or to enter W&W.

RESULTS

Of the 93 patients, 82.8% were re-evaluated and 20.8% had cCR. Patients in clinical stages II/III were significantly less likely to achieve cCR than those in stage I (p = 0.017). After a mean follow-up of 17.44 months, there were 4 regrowths in the 16 patients under W&W, all submitted to R0 surgery, ypN0; there were no deaths or local recurrences; one patient with regrowth had distant recurrence. Sixty patients underwent direct surgery after a mean follow-up of 16.23 months; 3 patients had local and distant recurrences; 7 others had only distant recurrences; there were 8 deaths. There were no statistically significant differences between patients under W&W and patients who underwent direct surgery regarding local or distant recurrences, or death (p > 0.9; p =  0.44; p =  0.19, respectively).

CONCLUSION

The W&W strategy for low rectal cancer achieved the same oncological outcomes as the traditional strategy while sparing some patients from surgery.

The risk of nodal disease in patients with pathological complete responses after neoadjuvant chemoradiation for rectal cancer: a systematic review, meta-analysis, and meta-regression

BACKGROUND

This systematic review and meta-analysis seek to evaluate the prevalence of nodal disease in rectal cancer patients with pathological complete responses (pCR) after neoadjuvant chemoradiotherapy (ypT0N+).

METHODS

This study conformed to the PRISMA guidelines. A search was performed on major databases to identify relevant articles. Meta-analyses of pooled proportions were performed on rectal cancer with pCR and ypT0N+. Meta-regression was undertaken to identify sources of heterogeneity, and the Newcastle-Ottawa Scale (NOS) was employed to assess the risk of bias.

RESULTS

A total of 18 studies were included, totaling 7568 patients. The overall risk of bias was low, since all studies scored 6 and above out of 9 on the NOS. Preoperatively, the pooled proportions of patients with T3/T4 tumors and clinically positive nodal disease were 84.08% (95% CI 74.19 to 91.99%) and 52.14% (95% CI 35.02 to 69.00%) respectively. The prevalence of pCR in the whole pool was 18.52% (95% CI 13.31 to 24.35%; I² = 93.85%; P = 0.00), and meta-regression showed a significantly negative relationship with patient age (β = - 0.03, 95% CI - 0.03 to - 0.02; P = 0.00). The pooled prevalence of ypT0N+ was 4.61% (95% CI 2.41 to 7.28%; I² = 52.27%; P = 0.01), and meta-regression demonstrated a significantly positive relationship with male gender (β = 1.06, 95% CI 1.00 to 1.12; P = 0.04).

CONCLUSION

There is a small risk of ypN+ in patients with pCR after neoadjuvant CRT and surgery for rectal cancer. However, further research is warranted to establish these findings and to identify predictive factors for this specific group of patients.

Predictors and Risk Factors of Pathologic Complete Response Following Neoadjuvant Chemoradiotherapy for Rectal Cancer: A Population-Based Analysis

Background: Patients with rectal cancer who achieve pathologic complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) may have a better prognosis and may be eligible for non-operative management. The aim of this research was to identify variables for predicting pCR in rectal cancer patients after nCRT and to define clinical risk factors for poor outcome after pCR to nCRT and radical resection in rectal cancer patients. Methods: A retrospective review was performed using the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2013. Non-metastatic rectal cancer patients who received radical resection after neoadjuvant chemoradiotherapy were included in this study. Multivariate analysis of the association between clinicopathological characteristics and pCR was performed, and a logistic regression model was used to identify independent predictors for pCR. A nomogram based on the multivariate logistics regression was built with decision curve analyses to evaluate the clinical usefulness. Results: A total of 6,555 patients were included in this study. The proportion of patients with pCR was 20.5% (n = 1,342). The nomogram based on multivariate logistic regression analysis showed that clinical T4 and N2 stages were the most significant independent clinical predictors for not achieving pCR, followed by mucinous adenocarcinoma and positive pre-treatment serum CEA results. The 3-year overall survival rate was 92.4% for those with pCR and 88.2% for those without pCR. Among all the pCR patients, mucinous adenocarcinoma patients had the worst survival, with a 3-year overall survival rate of 67.5%, whereas patients with common adenocarcinoma had an overall survival rate of 93.8% (P < 0.001). Univariate and multivariate analyses showed that histology and clinical N2 stage were independent risk factors. Conclusion: Mucinous adenocarcinoma, positive pre-treatment serum CEA results, and clinical T4 and N2 stages may impart difficulty for patients to achieve pCR. Mucinous adenocarcinoma and clinical N2 stage might be indicative of a prognostically unfavorable biological tumor profile with a greater propensity for local or distant recurrence and decreased survival.

Can clinicopathological parameters predict for lymph node metastases in ypT0-2 rectal carcinoma? Results of the CAO/ARO/AIO-94 and CAO/ARO/AIO-04 phase 3 trials

BACKGROUND

The advent of less radical surgical approaches has generated concern about leaving locoregional lymph node metastases (LNM) unresected that could lead to adverse outcome. We examined the prognostic role of clinicopathological factors for ypN-positivity in patients with ypT0-2 rectal carcinoma treated within the CAO/ARO/AIO-94 and CAO/ARO/AIO-04 randomized phase 3 trials.

METHODS

The correlation of clinicopathological factors with ypN-status (ypN0 vs ypN1/2) was examined in n = 776 patients with ypT0-2 rectal carcinoma after preoperative CRT and total mesorectal excision surgery using Pearson's Chi-squared test for categorical variables and Kruskal-Wallis' test for continuous variables. Multivariable analysis was performed using binary logistic regression to identify independent prognosticators for ypN-positivity.

RESULTS

Residual LNM (ypN+) were found in 6%, 20.8% and 21.4% of patients with ypT0, ypT1 and ypT2 carcinomas, respectively. Independent prognosticators for LNM were advanced ypT category (p = 0.002) and lymphatic invasion (p = 0.020). In a separate multivariable analysis performed upon exclusion of ypT-category due to multicollinearity with residual tumor diameter (RTD), lymphatic invasion (p = 0.015) and RTD ≥10 mm (p = 0.005) demonstrated strong correlation with LNM.

CONCLUSION

Advanced ypT-stage, lymphatic invasion and RTD ≥10 mm were prognostic factors for LNM in patients ypT0-2 rectal carcinoma treated with CRT and surgery within both phase 3 trials. The high incidence of LNM in the ypT1-2 group needs to be taken into consideration in the context of oncological safety and indicate that LE should be advocated with great caution in this patient subgroup. The prognostic pathological factor identified here could help guide decision of LE vs TME after standard CRT.

Prediction of N0 Irradiated Rectal Cancer Comparing MRI Before and After Preoperative Chemoradiotherapy

BACKGROUND

The prediction of lymph node status using MRI has an impact on the management of rectal cancer, both before and after preoperative chemoradiotherapy.

OBJECTIVE

The purpose of this study was to maximize the negative predictive value and sensitivity of mesorectal lymph node imaging after chemoradiotherapy because postchemoradiation node-negative patients may be treated with rectum-sparing approaches.

DESIGN

This was a retrospective study.

SETTINGS

The study was conducted at a tertiary care hospital.

PATIENTS

Sixty-four patients with locally advanced rectal cancer who underwent preoperative chemoradiotherapy and MRI for staging and the assessment of response were evaluated.

MAIN OUTCOME MEASURES

The sums of the sizes of all mesorectal lymph nodes in each patient on both prechemoradiotherapy and postchemoradiotherapy imaging data sets were calculated to determine the lymph node global size reduction rates, taking these to be the outcomes of the histopathologic findings. Other included measures were interobserver agreement regarding the prediction of node status based on morphologic criteria and the diagnostic performance of contrast-enhanced images.

RESULTS

Using a cutoff value of a 70% lymph node global size reduction rate with only 15 node-positive patients on histopathology, the sensitivity in the prediction of nodal status and negative predictive value were 93% (95% CI, 70.2%-98.8%) and 97% (95% CI, 82.9%-99.8%) for observer 1 and 100% (95% CI, 79.6%-100%) and 100% (95% CI, 62.9%-100%) for observer 2. The areas under the receiver operating characteristic curves for the 2 observers were 0.90 (95% CI, 0.82-0.98; p < 0.0001) for observer 1 and 0.65 (95% CI, 0.50-0.79; p = 0.08) for observer 2. The efficacy of the morphologic criteria and contrast-enhanced images in predicting node status was limited after chemoradiotherapy.

LIMITATIONS

This study is limited by its small sample size and retrospective nature.

CONCLUSIONS

Assessing the lymph node global size reduction rate value reduces the risk of undetected nodal metastases and may be helpful in better identifying suitable candidates for the local excision of early stage rectal cancer. See Video Abstract at http://links.lww.com/DCR/A412.

Clinical utility of pretreatment prediction of chemoradiotherapy response in rectal cancer: a review

Approximately 20% of all patients with locally advanced rectal cancer experience pathologically complete responses following neoadjuvant chemoradiotherapy (CRT) and standard surgery. The utility of radical surgery for patients exhibiting good CRT responses has been challenged. Organ-sparing strategies for selected patients exhibiting complete clinical responses include local excision or no immediate surgery. The subjects of this tailored management are patients whose presenting disease corresponds to current indications of neoadjuvant CRT, and their post-CRT tumor response is assessed by clinical and radiological examinations. However, a model predictive of the CRT response, applied before any treatment commenced, would be valuable to facilitate such a personalized approach. This would increase organ preservation, particularly in patients for whom upfront CRT is not generally prescribed. Molecular biomarkers hold the greatest promise for development of a pretreatment predictive model of CRT response. A combination of clinicopathological, radiological, and molecular markers will be necessary to render the model robust. Molecular research will also contribute to the development of drugs that can overcome the radioresistance of rectal tumors. Current treatments for rectal cancer are based on the expected prognosis given the presenting disease extent. In the future, treatment schemes may be modified by including the predicted CRT response evaluated at presentation.

High nodal positivity rates even in good clinical responders after chemoradiation of rectal cancer: is organ preservation feasible?

AIM

Local excision (LE) is emerging as a treatment option for rectal cancer responding well to chemoradiation. However, it does not address the mesorectal nodal burden. We aimed to identify the factors influencing nodal positivity and subsequently defined a low-risk group by including only patients at low risk.

METHOD

A single-centre, retrospective database analysis was carried out of patients with radically resected rectal cancer after neoadjuvant chemoradiation.

RESULTS

This study included 524 patients with predominantly low rectal tumours. Nodal positivity among ypT0, T1 and T2 groups was 14.7%, 28% and 30%, respectively. Multivariate analysis with stepwise logistic regression identified the following low-risk features: age ≥ 40 years, nonsignet ring cell carcinoma (SRCC) histology and pathological complete response (pCR). Sixty-nine patients fulfilling all three criteria were analysed and the nodal positivity was found to be 10.1%, which implies that, if these patients had been selected for LE, one in 10 would have had positive mesorectal nodes.

CONCLUSION

Even in patients with low-risk criteria (pCR, non-SRCC histology and age ≥ 40 years), the residual positive nodal disease burden is 10%. Whether this high incidence of residual nodal disease translates into a similar risk of locoregional recurrence if an organ-preservation strategy is adopted is unclear.

Long-Term Outcome of Rectal Cancer With Clinically (EUS/MRI) Metastatic Mesorectal Lymph Nodes Treated by Neoadjuvant Chemoradiation: Role of Organ Preservation Strategies in Relation to Pathologic Response

BACKGROUND

Organ preservation strategies are under investigation for patients with locally advanced rectal cancer (LARC) who achieve a complete pathologic response in the primary tumor (ypT0) after neoadjuvant chemoradiation therapy (CRT). This study explored the value of this approach for cN+ patients.

METHODS

Data were retrieved from our institutional prospective rectal cancer database. Tumors with mesorectal lymph nodes larger than 5 mm shown on endorectal ultrasonography, pelvic magnetic resonance imaging, or both were staged as cN+.

RESULTS

The study population comprised 226 patients (142 men and 84 women; median age, 64 years) with LARC who underwent CRT followed by surgery including total mesorectal excision (TME) (n = 179) and full-thickness local excision (LE) (n = 47) between 1996 and 2013. At staging, 123 patients (54.4 %) were cN+. In 65 cases (28.7 %), ypCR was observed. Metastatic mesorectal lymph nodes (ypN+) were detected in 41.6 % of the cN+ patients and in 2.8 % of the cN0 patients (P < 0.01). Among the cN+ patients, 16 % of the ypT0 cases were ypN+ compared with 51.8 % of the no-ypT0 cases (P < 0.01). Among the cN+ patients who underwent TME, the 5-year disease-specific survival (DSS) and disease-free survival (DFS) rates were respectively 100 and 91.6 % for the ypT0 patients compared with 71.2 and 58.0 % for the no-ypT0 patients (P = 0.01). Among the ypN+ patients, the 5-year DSS and DFS rates were both 100 % for the ypT0 cases compared with 59.1 and 43.3 % for the no-ypT0 patients. Among the cN+ and ypT0 patients, the 5-year DSS and DFS were respectively 100 and 85.7 % for the TME patients compared with 100 and 91.6 % for the LE patients. In the multivariate analysis, ypT0 was the only independent prognostic factor.

CONCLUSIONS

Protocols aimed at organ preservation in LARC that achieve ypT0 after CRT can be offered also to cN+ patients.

Oncologic Safety of Local Excision Compared With Total Mesorectal Excision for ypT0-T1 Rectal Cancer: A Propensity Score Analysis

Good oncologic outcomes, demonstrated by a complete pathologic response after preoperative chemoradiotherapy (PCRT), have led to local excision (LE) in selected patients with rectal cancer. We evaluated the oncologic safety of LE compared with total mesorectal excision (TME) in patients with ypT0-T1 rectal cancer.A retrospective review of 304 patients who underwent PCRT, followed by LE or TME, for ypT0-T1 rectal cancer was performed. Propensity scores were computed and used to match groups (LE:TME = 1:1), and analysis of disease-free survival (DFS) and overall survival (OS) was made by comparing patients who underwent LE or TME. Prognostic factors of relapse were analyzed for all patients.Tumor categories were ypT0 in 25 (61.9%) cases, ypTis in 6 (14.3%) cases, and ypT1 in 11 (26.2%) cases for the LE group, and ypT0 in 28 (66.7%) cases, ypTis in 4 (9.5%) cases, and ypT1 in 10 (23.8%) cases for the matched TME patients. There was no significant difference between the matched LE and TME groups in relapse (4.8% and 7.14%, respectively; P = 0.646), 5-year DFS (95.2% vs 91.6%; P = 0.33) and 5-year OS (96.6% vs 88.0%; P = 0.238). In the multivariate Cox regression analysis, tumor distance from the anal verge (hazard ratio [HR] = 0.78; 95% confidence interval (CI) = 0.616-0.992) and the tumor grade (HR = 4.29; 95% CI = 1.430-12.886) were significantly associated with the recurrence risk.LE results in oncologic outcomes that are comparable to those achieved by TME in selected patients with ypT0-T1 rectal cancer after PCRT.

Local excision of low rectal cancer treated by chemoradiotherapy: is it safe for all patients with suspicion of complete tumor response?

PURPOSE

The purpose of this study is to assess if local excision (LE) could be proposed if suspicion of complete tumor response (CR) after neoadjuvant chemoradiotherapy (CRT) for low rectal cancer (LRC) and this despite a potential risk of nodes (N+) or other tumor deposits (OTD) left in place. The aim was to assess in patients with LRC treated by CRT: (a) pathologic results of LE and total mesorectal excision (TME) in case of preoperative suspicion of CR and (b) the risk of N+ or OTD on TME if ypT0-Tis-T1 tumor.

PATIENTS

Among 202 patients with LRC after CRT, 33 (16 %) with suspicion of CR underwent LE (n = 20) because of comorbidities and/or indication of definitive stoma or TME (n = 13). Pathologic examination of LE and TME specimens and oncological outcomes were assessed. Furthermore, 40/202 patients with pathologic CR on TME specimen (ypT0-Tis-T1) were assessed for possible N+ or OTD.

RESULTS

In the 33 patients with suspicion of CR: (a) after LE, tumor was ypT0-Tis-T1 in only 15/20 cases (75 %); (b) after TME, tumor was ypT0-Tis-T1 in only 7/13 cases (54 %). Among 40 patients with ypT0-Tis-T1 tumor on TME specimen, 4 (10 %) presented N+ and/or OTD.

CONCLUSION

In LRC with suspicion of CR after CRT, LE deserves a word of caution: 25 % of patients have in fact ypT2-T3 tumors. Furthermore, in patients with ypT0-Tis or T1 on TME specimen, a 10 % risk of N+ and/or ODT is observed. Thus, patient with suspicion of CR after CRT and treated by LE is exposed to a possible incomplete oncologic treatment.

Utility of rectoscopy in the assessment of response to neoadjuvant treatment for locally advanced rectal cancer

BACKGROUND/AIMS

The management of locally advanced rectal cancer has changed substantially over the last few decades with neoadjuvant chemoradiotherapy. The aim of the present study is to compare the results between neoadjuvant post-treatment rectoscopy and the anatomopathological findings of the surgical specimen.

PATIENTS AND METHODS

We conducted a prospective study of 67 patients with locally advanced adenocarcinoma of the rectum (stages II and III). Two groups were established: One with complete clinical response (cCR) and one without (non-cCR), based on the findings at rectoscopy. Assessment of tumor regression grade in the surgical specimen was determined using Mandard's tumor regression scale.

RESULTS

Seventeen patients showed a cCR. Thirty-five biopsies were negative and 32 were positive for malignancy. All the cCR patients had a negative biopsy (P < 0.0001). All 32 positive biopsies revealed the presence of adenocarcinoma, and of the 35 negative biopsies, 18 had no malignancy and 17 were diagnosed with adenocarcinoma (P < 0.0001). Sixteen of the 17 cCR patients showed a complete pathological response and one patient showed the presence of adenocarcinoma. Of the 50 non-cCR patients 48 revealed the presence of adenocarcinoma and two had absence of malignancy. According to the Mandard classification, 16 of the 17 cCR patients were grade I and 1 grade II; 2 non-cCR patients were grade I, 7 grade II, 13 grade III, 19 grade IV, and 9 grade V.

CONCLUSIONS

Endoscopic and histological findings could be determinants in the assessment of response to neoadjuvant treatment.

Rectal cancer with complete clinical response after neoadjuvant chemoradiotherapy, surgery, or "watch and wait"

PURPOSE

The purpose of this study was to compare the outcomes of patients treated with chemoradiotherapy with a complete clinical response followed by either a "watch and wait" strategy or a total mesorectal excision.

METHODS

This was an observational retrospective study from a single institute. Patients with locally advanced rectal cancer following chemoradiotherapy with a complete clinical response from January 1, 2007 to December 31, 2014 were included.

RESULTS

The study population consisted of 18 patients who opted for a "watch and wait" policy and 26 patients who underwent radical surgery after achieving a complete clinical response. Patients had no documented treatment complications under the watch and wait policy, while 13 patients who underwent radical surgery experienced significant morbidity. There were two local recurrences in the watch and wait group; both were treated with salvage resection and had no associated mortality. In the radical surgery group, 1 patient showed an incomplete pathologic response (ypT0N1), and the remaining 25 patients showed complete pathologic responses; 1 had a distant recurrence, which was managed non-operatively, and 2 patients died of unrelated causes. The 5-year overall survival rate and median disease-free survival time were 100% and 69.78 months in the watch and wait group and 92.30% and 89.04 months in the radical surgery group.

CONCLUSIONS

A watch and wait policy avoids the morbidity associated with radical surgery and preserves oncologic outcomes in our retrospective study from a single institute. It could be considered a therapeutic option in patients with locally advanced rectal cancer following chemoradiotherapy with a complete clinical response.

Complete radiotherapy response in rectal cancer: A review of the evidence

Complete response to chemoradiotherapy for rectal cancer is becoming a common clinical entity. Techniques to diagnose complete response and how to survey these patients without operative intervention are still unclear. We review the most recent evidence. Barriers to firm conclusions regarding this are heterogeneity of diagnostic definitions, differing surveillance protocols, and a lack of randomised studies.

Predictors of Pathologic Complete Response Following Neoadjuvant Chemoradiotherapy for Rectal Cancer

BACKGROUND

Some patients with rectal cancer who receive neoadjuvant chemoradiotherapy (nCRT) achieve a pathologic complete response (pCR) and may be eligible for less radical surgery or non-operative management. The aim of this study was to identify variables that predict pCR after nCRT for rectal cancer and to examine the impact of pCR on postoperative complications.

METHODS

A retrospective review was performed of the NCDB from 2006 to 2011. Patients with rectal cancer who received nCRT followed by radical resection were included in this study. Multivariable analysis of the association between clinicopathologic characteristics and pCR was performed, and propensity-adjusted analysis was used to identify differences in postoperative morbidity between pCR and non-pCR patients.

RESULTS

A total of 23,747 patients were included in the study. Factors associated with pCR included lower tumor grade, lower clinical T and N stage, higher radiation dose, and delaying surgery by more than 6-8 weeks after the end of radiation, while lack of health insurance was linked with a lower likelihood of pCR. Complete response was not associated with an increased risk of major postoperative complications.

CONCLUSIONS

Several clinical, pathologic, and treatment variables can help to predict which patients are most likely to have pCR after nCRT for rectal cancer. Awareness of these variables can be valuable in counseling patients regarding prognosis and treatment options.

The accuracy of MRI, endorectal ultrasonography, and computed tomography in predicting the response of locally advanced rectal cancer after preoperative therapy: A metaanalysis

BACKGROUND

To perform a metaanalysis to determine and compare the diagnostic performance of MRI, endorectal ultrasonography (ERUS), and computed tomography (CT) in predicting the response of locally advanced rectal cancer after preoperative therapy.

METHODS

All previously published articles on the role of MRI, CT, and/or ERUS in predicting the response of rectal cancer to preoperative therapy were collected. We divided the objective in 3 parts: the accuracy to assess (i) complete response, (ii) to detect T4 tumors with invasion to the circumferential resection margin (CRM), and (iii) to predict the presence of lymph node metastasis. The pooled estimates of, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated using a bivariate mixed effect analysis.

RESULTS

Forty-six studies comprising 2,224 patients were included. (i) The pooled accuracy to assess complete tumor response were (a) 75% for MRI, (b) 82% for ERUS, (c) and 83% for CT. (ii) Pooled accuracy to detect T4 tumors with invasion to the CRM were (a) 88% and (b) 94% for ERUS. (iii) Pooled accuracy to predict the presence of lymph node metastasis was (a) 72% for MRI, (b) 72% for ERUS, (c) and 65% for CT.

CONCLUSION

MRI, CT, and ERUS cannot be used to predict complete response of locally advanced rectal cancer after CRT. In addition, the positive predictive value for these imaging techniques is low for the assessment of tumor invasion in the CRM. The accuracy of the modalities to predict the presence of metastatic lymph node disease is also low.

The value of forceps biopsy and core needle biopsy in prediction of pathologic complete remission in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy

Patients with pathological complete remission (pCR) after treated with neoadjuvant chemoradiotherapy (nCRT) have better long-term outcome and may receive conservative treatments in locally advanced rectal cancer (LARC). The study aimed to evaluate the value of forceps biopsy and core needle biopsy in prediction of pCR in LARC treated with nCRT. In total, 120patients entered this study. Sixty-one consecutive patients received preoperative forceps biopsy during endoscopic examination. Ex vivo core needle biopsy was performed in resected specimens of another 43 consecutive patients. The accuracy for ex vivo core needle biopsy was significantly higher than forceps biopsy (76.7% vs. 36.1%; p < 0.001). The sensitivity for ex vivo core needle biopsy was significantly lower in good responder (TRG 3) than poor responder (TRG ≤ 2) (52.9% vs. 94.1%; p = 0.017). In vivo core needle biopsy was further performed in 16 patients with good response. Eleven patients had residual cancer cells in final resected specimens, among whom 4 (36.4%) patients were biopsy positive. In conclusion, routine forceps biopsy was of limited value in identifying pCR after nCRT. Although core needle biopsy might further identify a subset of patients with residual cancer cells, the accuracy was not substantially increased in good responders.

Comparison of the pathological response of the mesorectal positive nodes between short-course chemoradiotherapy with delayed surgery and long-course chemoradiotherapy in patients with rectal cancer

BACKGROUND

The aim of this study was to compare the pathological response of mesorectal positive nodes between short-course chemoradiotherapy with delayed surgery (SCRT-delay) and long-course chemoradiotherapy (LC-CRT) in patients with rectal cancer.

METHOD

The resected primary tumor specimens following the two different approaches were assessed utilizing the tumor regression grade (TRG 0-4), and each positive lymph node was assessed according to the lymph node regression grade (LRG 1-3), with TRG 4 and LRG 3 indicating total regression. The lymph node sizes were measured to elucidate any correlation with LRG scores.

RESULTS

Seventy-four patients with ypN-positive rectal cancer had 220 positive lymph nodes following the SCRT-delay, and 48 patients had 141 positive lymph nodes following the LC-CRT. The distribution of LRG 1/2/3 in the two groups was 123/72/25 and 60/31/50 (p < 0.001), respectively, and the distribution of TRG 0/1/2/3/4 in the two groups was 36/19/19/0 and 12/15/20/1 (p = 0.005), respectively. The requirements of total regression of positive lymph nodes were a primary tumor degenerated to TRG 3 with a size less than 6 mm in SCRT-delay (sensitivity, 60.9 %) or a primary tumor degenerated to TRG 2-4 with a size less than 5 mm at TRG 2 (sensitivity, 57.6 %) or 6 mm at TRG 3 and 4 (sensitivity, 84.2 %) in LC-CRT as indicated by the receiver operating characteristic curve analysis.

CONCLUSION

The tumor regression effect of LC-CRT on the primary tumor and positive nodes was more favorable than SCRT-delay, and LC-CRT is able to predict the LRG 3 response with a high sensitivity.

The impact of lymph node size to predict nodal metastasis in patients with rectal cancer after preoperative chemoradiotherapy

PURPOSE

During restaging after preoperative chemoradiotherapy (CRT), the assessment of lymph node (LN) metastasis is vital for selecting further treatment strategies. This study aimed to evaluate the impact of LN size to predict LN metastasis in rectal cancer patients after preoperative CRT.

METHODS

A total of 30 consecutive patients who underwent preoperative CRT followed by curative resection of primary rectal cancer were selected as a study group (CRT group). As a control group (non-CRT group), 30 patients who underwent primary tumor resection were selected using a 1:1 case-match design. Matching criteria were gender, age, and clinical T stage. The size of each LN was measured from the surgical specimen. To clarify optimal cutoff values for node size according to the risk of detecting metastasis, receiving-operator characteristic (ROC) curves were generated.

RESULTS

In the non-CRT group, 39/474 LNs were confirmed to have metastasis. In the CRT group, 29/422 LNs showed metastasis. The median size of metastatic LNs was 6.0 mm in CRT group, which was significantly larger than 4.0 mm in the non-CRT group (p = 0.006). The optimal cutoff value for determining metastasis in the CRT group was 4.5 mm, compared to 3.5 mm in the non-CRT group. The accuracy of the cutoff value was much higher in the CRT group (CRT vs. non-CRT, 77.9 vs. 59.9%).

CONCLUSIONS

LN size is a strong indicator for prediction of regional LN metastasis in rectal cancer patients after preoperative CRT, compared to those without CRT.

A minimum yield of twelve lymph nodes in rectal cancer remains valid in the era of neo-adjuvant treatment : results from a national cohort study

PURPOSE

The purpose of the study was to examine if a minimum of 12 lymph nodes (LNs) is still valid in rectal cancer after neo-adjuvant treatment.

METHODS

An analysis was carried out in a nationwide Danish cohort of 6793 patients, treated by curative resection of stage I-III rectal cancer during the period 2003-2011. The cohort was divided into two groups according to whether neo-adjuvant treatment had been given. The groups were analysed separately and were further analysed according to four lymph node yield (LNY) groups 0-5, 6-11, 12-17 and ≥18.

RESULTS

Two thousand one hundred twenty-three patients (31.0 %) received neo-adjuvant treatment. A median LNY of 10 and 15 (p < 0.0001) and rates of node-positive (N-positive) disease of 31.6 and 36.7 % (p < 0.001) were observed with and without (+/-) neo-adjuvant treatment, respectively. The rate of N-positive disease according to tumour stage ranged from 4.8 %/11.4 % (ypT0/pT1) to 42.1 %/64.1 % (ypT4/pT4). The rate of N-positive disease according to LNY ranged from 19.5 %/16.8 % (0-5 LNs) to 42.6 %/37.9 % (≥18 LNs) (-/+neo-adjuvant treatment). In a logistic regression analysis, a significant association was found between N-positive disease and pT/ypT stage as well as between N-positive disease and LNY.

CONCLUSIONS

A significantly smaller ratio of N-positive disease was observed in the group of patients who had received neo-adjuvant treatment. The ratio of N-positive disease increased significantly with more advanced tumour stage and increasing LNY irrespective of neo-adjuvant treatment. A minimum of 12 LNs is needed to ensure N-negative disease, irrespective of neo-adjuvant treatment.

Organ preservation in rectal cancer: have all questions been answered?

Improved treatment strategies have eliminated local control as the major problem in rectal cancer. With increasing awareness of long-term toxic effects in survivors of rectal cancer, organ-preservation strategies are becoming more popular. After chemoradiotherapy, both watchful waiting and local excision are used as possible alternatives for radical surgery. Although these seem attractive strategies, many issues about the safety of organ preservation remain. Additionally, radiotherapy strategies are mainly aimed at intermediate and high-risk rectal tumours, and adaptation of this standard practice for a completely new treatment indication has yet to start. This Review will discuss the options and problems of organ preservation, and address the research questions that need to be answered in the coming years, with a specific focus on radiotherapy.

Nomogram to predict ypN status after chemoradiation in patients with locally advanced rectal cancer

Background:

Pelvic lymph node (LN) status after preoperative chemoradiotherapy (CRT) is an important indicator of oncologic outcome in patients with locally advanced rectal cancer. The purpose of this study was to develop a nomogram to predict LN status after preoperative CRT in locally advanced rectal cancer patients.

Methods:

The nomogram was developed in a training cohort (n=891) using logistic regression analyses and validated in a validation cohort (n=258) from a prospectively registered tumour registry at Asan Medical Center. The model was internally and externally validated for discrimination and calibration using bootstrap resampling. Model performance was evaluated by the concordance index (c-index) and calibration curve.

Results:

Pretreatment ypT stage, patient age, preCRT tumour differentiation, cN stage, lymphovascular invasion, and perineural invasion were reliable predictors of LN metastasis after preoperative CRT. The nomogram developed using these parameters had c-indices of 0.81 (training) and 0.77 (validation). The calibration plot suggested good agreement between actual and nomogram-predicted LN status after preoperative CRT.

Conclusions:

This nomogram improves prediction of LN status after preoperative CRT in patients with locally advanced rectal cancer. It will be useful for counselling patients as well as for the design and stratification of patients in clinical trials.

p27 expression in post-treatment rectal cancer: a potential novel approach for predicting residual nodal disease

BACKGROUND

Expression profiles of p21, p27, p53, Ki-67, and thymidylate synthase may be associated with response to neoadjuvant chemoradiation. The relationship between post-treatment protein expression and regional lymph node involvement has not been fully explored.

METHODS

Tumor cores from 126 rectal cancer patients underwent immunohistochemical analysis for the aforementioned proteins. Staining indices (SIs) using percentage of stained cells and staining intensity were calculated for 10 tumor cores per patient. SI for each marker was compared between node negative and node positive patients.

RESULTS

Twenty-six (20.6%) cancer patients had a pathologic complete response and 37 had inadequate tissue or cancer cells, leaving 63 for analysis. Thirty-seven (58.7%) cancer patients were node negative and 26 (41.3%) were node positive. There was an association between increased p27 SI and nodal positivity (P = .04).

CONCLUSION

Increased p27 expression in post-treatment rectal cancer is associated with nodal positivity and may determine which patients are suitable for local excision.

Paradigm-shifting new evidence for treatment of rectal cancer

BACKGROUND

Treatment of rectal cancer has dramatically evolved during the last three decades shifting toward a tailored approach based on preoperative staging and response to neoadjuvant combined modality therapy (CMT).

METHODS

A literature search was performed using PubMed/Medline electronic databases.

RESULTS

Selected patients with T1 N0 rectal cancer are best treated with local excision by transanal endoscopic microsurgery (TEM). Satisfactory results have been reported after CMT and TEM for the treatment of highly selected T2 N0 rectal cancers. CMT followed by rectal resection and total mesorectal excision is considered the standard of care for the treatment of locally advanced rectal cancer. However, a subset of stage II and III patients may not require neoadjuvant radiation treatment. Finally, there are mounting data supporting a "watch and wait" approach or local excision in patients with complete clinical response after neoadjuvant CMT.

CONCLUSIONS

Current evidence shows that selected T1 N0 rectal cancers can be managed by TEM alone, while locally advanced cancers should be treated by CMT followed by radical surgery. Studies are underway to identify patients that do not benefit from neoadjuvant radiation therapy. A non-operative approach in case of complete clinical response must be validated by large prospective studies.

T4 rectal cancer: do we always need an exenteration?

The management of rectal cancer has changed dramatically over the last few decades. Due to improvements in the multimodality treatment and the introduction of neoadjuvant chemoradiation, previously irresectable tumours can nowadays be cured by extensive multivisceral resections. These highly complex operations are associated with significant morbidity and mortality. Due to optimization of chemoradiotherapy, the introduction of IORT, increasing knowledge of tumour pathology and patterns of recurrence the need for extensive surgery diminishes. The question arises which patients with T4 rectal cancer really need extensive surgery and who can safely be considered for an organ preserving approach.

Risk factors for local recurrence following neoadjuvant chemoradiotherapy for rectal cancers

Local recurrence (LR) has an adverse impact on rectal cancer treatment. Neoadjuvant chemoradiotherapy (nCRT) is increasingly administered to patients with progressive cancers to improve the prognosis. However, LR still remains a problem and its pattern can alter. Correspondingly, new risk factors have emerged in the context of nCRT in addition to the traditional risk factors in patients receiving non-neoadjuvant therapies. These risk factors are decisive when reviewing treatment options. This review aims to elucidate the distinctive risk factors related to LR of rectal cancers in patients receiving nCRT and to clarify their clinical significance. A search was conducted on PubMed to identify original studies investigating patients with rectal cancer receiving nCRT. Outcomes of interest, especially potential risk factors for LR in patients with nCRT, were then analyzed. The clinical importance of these risk factors is discussed. Remnant cancer cells, lymph-nodes and tumor response were found to be major risk factors. Remnant cancer cells decide the status of resection margins. Local excision following nCRT is promising in ypT0-1N0M0 cases. Dissection of lateral lymph nodes should be considered in advanced low-lying cancers. Although better tumor response resulted in a relatively lower recurrence rate, the evidence available is insufficient to justify a non-operative approach in clinical complete responders to nCRT. LR cannot be totally avoided by current multidisciplinary approaches. The related risk factors resulting from nCRT should be considered when making decisions regarding treatment selection.

Modern rectal cancer multidisciplinary treatment: the role of radiation and surgery

INTRODUCTION

Treatment of rectal cancer has evolved during the last few decades due to more in-depth knowledge of rectal cancer biology and major advances in the field of preoperative staging, medical management and surgical techniques. Consequently, treatment strategies are shifting moving towards a more personalized approach based on the response to treatment. Currently topics of controversy are centered around the indication for neoadjuvant radiation therapy in locally advanced rectal cancer and the role of surgery in patients with complete clinical response after neoadjuvant combined modality therapy. This manuscript aims to critically evaluate the evolution of treatment of rectal cancer during the last three decades and future directions.

METHODS

A review of the literature has been performed in PubMed/Medline electronic databases.

RESULTS

Treatment modalities are moving towards a tailored approach to rectal cancer patients based on the response to chemoradiation. A "wait-and-see" approach and local excision by Transanal Endoscopic Microsurgery (TEM) are strategies recently proposed in case of complete clinical response.

CONCLUSIONS

The standard of care still requires that locally advanced rectal cancer should be treated by neoadjuvant chemoradiation therapy followed by total mesorectal excision, including patients with a clinical complete response. Further evidence is needed to endorse a "wait-and-see" strategy and to define the role of TEM.

Transanal endoscopic microsurgery: what indications in 2013?

Thanks to major advances in the field of surgical techniques and neoadjuvant chemoradiation therapy, along with more accurate pre-operative staging tools and the widespread introduction of population-based screening programs, treatment of rectal cancer has been evolving over the past few decades, moving towards a more tailored approach. This has brought a shift in the treatment algorithm of benign rectal lesions and selected early rectal cancers, for which today transanal endoscopic microsurgery (TEM) is accepted as an effective alternative to abdominal surgery.

In 2013, topics of controversy are the role of TEM in the treatment of more advanced rectal cancers, in cases of complete pathological response after chemoradiation therapy and the role of TEM as a platform for single-port surgery and NOTES. This article reviews the current indications for TEM and the future perspectives of this approach in the treatment of rectal tumors.

Comparative analysis of lymph node metastases in patients with ypT0-2 rectal cancers after neoadjuvant chemoradiotherapy

BACKGROUND

Neoadjuvant chemoradiotherapy before total mesorectal excision for rectal cancer is associated with improved local tumor control, primary tumor regression, and pathologic downstaging. Therefore, tumor response in the bowel wall has been proposed to be used to identify patients for organ-preserving strategies.

OBJECTIVE

The aim of this study was to determine the rate of residual lymph node involvement following neoadjuvant chemoradiotherapy among patients with ypT0-2 residual bowel wall tumor and to comparatively assess their oncologic outcomes following total mesorectal excision.

DESIGN

This is a retrospective consecutive cohort study, 1993 to 2008.

SETTING AND PATIENTS

Patients with stage cII to III rectal carcinoma treated with preoperative chemoradiotherapy and total mesorectal excision were included.

MAIN OUTCOME MEASURES

The primary outcomes measured were the rate of lymph node metastasis by ypT stage, recurrence-free survival, and the frequencies of distant metastasis and local recurrence.

RESULTS

Among all 406 ypT0-2 patients, 66 (16.3%) had lymph node metastasis: 20.8% among ypT2, 17.1% among ypT1, and 9.1% among ypT0 patients. Local recurrences (2.0% vs 5.5%; p = 0.038) but not distant metastases (9.3% vs 13.5%; p = 0.38) occurred more frequently in ypN+ than in ypN0 patients. Recurrence-free survival was 85.2% among ypT0-2N0 and 79.6% for ypT0-2N+ patients (p = 0.28). The lack of difference in recurrence-free survival persisted after covariate adjustment (HR, 1.29; 95% CI, 0.77-2.16; p = 0.37). However, among ypT3-4 patients, 5-year recurrence-free survival was significantly lower with lymph node metastasis (HR, 1.51; 95% CI, 1.07-2.12; p = 0.019).

LIMITATIONS

Low local recurrence event rate limited further comparison by ypT0-2 subgroups.

CONCLUSIONS

Residual mesorectal lymph node metastasis risk remains high even with good neoadjuvant chemoradiotherapy response within the bowel wall. Complete removal of the mesorectal burden results in excellent disease control. Given the uniquely good outcomes with standard therapy among patients with ypT0-2 disease, the use of ypT stage to stratify patients for local excision risks undertreatment of an unacceptably high proportion of patients.

Transanal endoscopic microsurgery for residual rectal cancer (ypT0-2) following neoadjuvant chemoradiation therapy: another word of caution

BACKGROUND

Significant tumor downstaging among patients with rectal cancer following neoadjuvant chemoradiation has raised the issue of offering patients with small residual cancers restricted to the bowel wall an alternative treatment strategy to total mesorectal excision. Transanal endoscopic microsurgery may allow proper primary tumor resection with promising oncological outcomes, less postoperative morbidity, and minimal long-term sexual, urinary, and fecal continence disorders in comparison with radical resection.

OBJECTIVE

The aim of this study was to determine the oncological outcomes of patients with residual rectal cancers restricted to the rectal wall (ypT0-2) following neoadjuvant chemoradiation and transanal endoscopic microsurgery.

DESIGN

This study considered a prospective cohort of patients with residual rectal cancers following neoadjuvant chemoradiation treated by transanal endoscopic microsurgery and no additional systemic therapy.

SETTINGS

This study was a single-institution experience.

PATIENTS

Patients with adenocarcinoma of the rectum located no more than 7 cm from the anal verge and endorectal ultrasound- or magnetic resonance-staged cT2-4N0-2M0 treated by neoadjuvant chemoradiation (50.4-54 Gy and 5-fluorouracil-based chemotherapy) were eligible for the study. Patients with small residual tumors (≤3 cm) radiologically staged ycT0-2N0 were treated by transanal endoscopic microsurgery.

INTERVENTIONS

Transanal endoscopic microsurgery was performed.

MAIN OUTCOME MEASURES

The primary outcome measured was local recurrence.

RESULTS

Of the 27 patients treated by transanal endoscopic microsurgery, 3 had ypT0, 6 had ypT1, and 18 had ypT2 cancers. All patients underwent R0 transanal endoscopic microsurgery excision. Local recurrence was observed in 4 (15%) patients after a median follow-up of 15 months. Only lymphovascular invasion was an independent predictive factor for local failure (p = 0.04). Tumor size, ypT status, T-status downstaging, lateral/radial margins, and tumor regression grade were not predictors of local failure.

LIMITATIONS

This study was limited by the small sample size and limited follow-up.

CONCLUSIONS

A local failure rate of 15% after transanal endoscopic microsurgery for patients with residual rectal cancers restricted to the bowel wall (ypT0-2) may limit the indication of this procedure to highly selected patients as an alternative to standard radical total mesorectal excision.

Oncologic outcome after preoperative chemoradiotherapy in patients with pathologic T0 (ypT0) rectal cancer

BACKGROUND

Little is known about the oncologic outcomes of patients with ypT0 rectal cancer after preoperative chemoradiotherapy.

OBJECTIVE

To evaluate the clinicopathologic characteristics and oncologic outcomes of patients with ypT0 rectal cancer after preoperative chemoradiotherapy and curative radical surgery.

DESIGN AND SETTINGS

This was a retrospective review of factors influencing outcome of patients treated with preoperative chemoradiotherapy for rectal cancer at a tertiary care university medical center in Seoul, Korea between 2000 and 2008.

PATIENTS

A total of 830 rectal cancer patients underwent surgery after preoperative chemoradiotherapy. Patients were included in the study if they had a pretreatment clinical classification of T3-4 or N+ (or T2N0 and preoperative chemoradiotherapy for sphincter preservation) and if they were classified on pathologic examination as ypT0 after preoperative CRT and curative radical surgery. Patients were classified as.

MAIN OUTCOME MEASURES

Overall survival and disease-free survival were evaluated in relation to ypT0N0 or ypT0N1-2 status and other factors that might influence outcome.

RESULTS

Of 91 patients included in the study, 54 (59.3%) were men; the mean patient age was 55 (SD, 11) years, and mean follow-up duration was 44 (SD, 23) months. Surgical procedures included low anterior resection in 68 patients, abdominoperineal resection in 21, and intersphincteric resection in 2. Mean tumor distance from the anal verge was 4.7 (SD, 1.8) cm. Of the 91 patients, 85 were classified as ypT0N0 and 6 as ypT0N1-2. No patient experienced local recurrence. A total of 11 patients (12.1%) had distant metastases, after a mean 11.1 months, including 7 (8.2%) with ypT0N0 and 4 (66.7%) with ypT0N1-2 tumors. One patient with ypT0N0 and 2 patients with ypT0N1-2 tumors died of metastasis. In patients classified as ypT0N0, the 5-year disease free survival and overall survival rates were 82.3% and 89.2%, respectively. Multivariate analysis showed that ypN1-2 status (p = 0.001) was a significant independent risk factor for recurrence (decreased 5-year disease-free survival), but no factor was associated with 5-year overall survival.

LIMITATIONS

The study is limited by its retrospective nature.

CONCLUSION

Oncologic outcomes in patients with ypT0N0 rectal cancer were excellent. The presence of residual cancer cells in mesorectal lymph nodes represents a risk factor for distant metastasis.

Elevated CEA levels and low distance of the tumor from the anal verge are predictors of incomplete response to chemoradiation in patients with rectal cancer

BACKGROUND

The objective of this study was to evaluate pretreatment clinical parameters as predictive factors for complete pathological response after long-term chemoradiotherapy (RCT) for rectal cancer. Tumor downstaging after RCT for rectal cancer can be obtained in half of cases, whereas a complete pathological response (CPR) is reported to range between 15 and 30%. It is not possible to foresee before therapies who will respond.

METHODS

Patients with stage II-III rectal cancer that had undergone RCT and rectal resection between January 1995 and October 2010 were considered. Patients were divided in those who achieved a CPR, "CR" group, and those who did not achieve a CPR, "NCR" group. Univariate and multivariate analyses between groups were performed considering the clinical parameters: gender, age, ASA score, preoperative hematic CEA, tumor grading; distance of the tumor from the anal verge, maximum tumor diameter, TNM stage, and neoadjuvant treatment details.

RESULTS

Among 260 patients, 43 (16.5%) achieved a CPR. The two groups resulted homogeneous for age, sex, pretreatment status, and tumor stage. A CEA <5 ng/dl and distance from anal verge >5 cm were correlated with CPR at multivariate analysis. Patients with both these conditions presented a significantly higher CPR rate (30.6%) as well as improved 5-year survival. CPR was also correlated with improved survival.

CONCLUSIONS

Very low tumors with a high serum CEA are very unlikely to reach a CPR. The predictive value of these easily available clinical factors should not be underestimated, and better therapeutic strategies for these tumors are needed.

Complete pathologic response after combined modality treatment for rectal cancer and long-term survival: a meta-analysis

BACKGROUND

Complete pathologic response (CPR) after neoadjuvant chemoradiotherapy (combined modality treatment, CMT) for rectal cancer seems associated with improved survival compared to partial or no response (NPR). However, previous reports have been limited by small sample size and single-institution design.

METHODS

A systematic literature review was conducted to detect studies comparing long-term results of patients with CPR and NPR after CMT for rectal cancer. Variables were pooled only if evaluated by 3 or more studies. Study end points included rates of CPR, local recurrence (LR), distant recurrence (DR), 5-year overall survival (OS), and disease-free survival (DFS).

RESULTS

Twelve studies (1,913 patients) with rectal cancer treated with CMT were included. CPR was observed in 300 patients (15.6%). CPR and NPR patient groups were similar with respect to age, sex, tumor size, distance of tumor from the anus, and stage of disease before treatment. Median follow-up ranged from 23 to 46 months. CPR patients had lower rates of LR [0.7% vs. 2.6%; odds ratio (OR) 0.45, 95% confidence interval (CI) 0.22-0.90, P = 0.03], DR (5.3% vs. 24.1%; OR 0.15, 95% CI 0.07-0.31, P = 0.0001), and simultaneous LR + DR (0.7% vs. 4.8%; OR 0.32, 95% CI 0.13-0.79, P = 0.01). OS was 92.9% for CPR versus 73.4% for NPR (OR 3.6, 95% CI 1.84-7.22, P = 0.002), and DFS was 86.9% versus 63.9% (OR 3.53, 95% CI 1.62-7.72, P = 0.002).

CONCLUSIONS

CPR after CMT for rectal cancer is associated with improved local and distal control as well as better OS and DFS.

Role of biopsies in patients with residual rectal cancer following neoadjuvant chemoradiation after downsizing: can they rule out persisting cancer?

AIM

The study aimed to determine the value of postchemoradiation biopsies, performed after significant tumour downsizing following neoadjuvant therapy, in predicting complete tumour regression in patients with distal rectal cancer.

METHOD

A retrospective comparative study was performed in patients with rectal cancer who achieved an incomplete clinical response after neoadjuvant chemoradiotherapy. Patients with significant tumour downsizing (> 30% of the initial tumour size) were compared with controls (< 30% reduction of the initial tumour size). During flexible proctoscopy carried out postchemoradiation, biopsies were performed using 3-mm biopsy forceps. The biopsy results were compared with the histopathological findings of the resected specimen. UICC (Union for International Cancer Control) ypTNM classification, tumour differentiation and regression grade were evaluated. The main outcome measures were sensitivity and specificity, negative and positive predictive values, and accuracy of a simple forceps biopsy for predicting pathological response after neoadjuvant chemoradiotherapy.

RESULTS

Of the 172 patients, 112 were considered to have had an incomplete clinical response and were included in the study. Thirty-nine patients achieved significant tumour downsizing and underwent postchemoradiation biopsies. Overall, 53 biopsies were carried out. Of the 39 patients who achieved significant tumour downsizing, the biopsy result was positive in 25 and negative in 14. Only three of the patients with a negative biopsy result were found to have had a complete pathological response (giving a negative predictive value of 21%). Considering all biopsies performed, only three of 28 negative biopsies were true negatives, giving a negative predictive value of 11%.

CONCLUSION

In patients with distal rectal cancer undergoing neoadjuvant chemoradiation, post-treatment biopsies are of limited clinical value in ruling out persisting cancer. A negative biopsy result after a near-complete clinical response should not be considered sufficient for avoiding a radical resection.

Shifting concepts in rectal cancer management: a review of contemporary primary rectal cancer treatment strategies

The management of rectal cancer has transformed over the last 3 decades and continues to evolve. Some of these changes parallel progress made with other cancers: refinement of surgical technique to improve organ preservation, selective use of neoadjuvant (and adjuvant) therapy, and emergence of criteria suggesting a role for individually tailored therapy. Other changes are driven by fairly unique issues including functional considerations, rectal anatomic features, and surgical technical issues. Further complexity is due to the variety of staging modalities (each with its own limitations), neoadjuvant treatment alternatives, and competing strategies for sequencing multimodal treatment even for nonmetastatic disease. Importantly, observations of tumor response made in the era of neoadjuvant therapy are reshaping some traditionally held concepts about tumor behavior. Frameworks for prioritizing and integrating complex data can help to formulate treatment plans for patients.

A single-centre experience of chemoradiotherapy for rectal cancer: is there potential for nonoperative management?

AIM

The aim of the study was to assess the outcome of patients who received chemoradiotherapy (CRT) for locally advanced rectal cancer, specifically those with complete clinical response (CCR) and who were then managed nonoperatively with a 'Watch and Wait' follow-up protocol.

METHOD

A retrospective study was carried out of patients undergoing preoperative CRT for rectal cancer, conducted in a district general hospital managing rectal cancer through the multidisciplinary team process.

RESULTS

Forty-nine patients received preoperative CRT over a 5-year period (2004-2009). Twelve (24%) were considered potentially to have had a complete response on MRI. Of these, six subsequently had clinical evidence of residual disease, leading to surgery (mean time to surgery, 24 weeks; range, 12-36 weeks). The remaining six had CCR, avoiding surgery (mean follow up, 26 months; range, 12-45 months), with all six patients disease free to date. A further six patients had complete pathological response (CPR) following surgery after comprehensive histopathological assessment of the specimen.

CONCLUSION

In this consecutive series of patients with locally advanced rectal cancer treated with CRT, 12% demonstrated a CCR and have been actively managed conservatively, thereby avoiding surgery. With further improvements in diagnostic assessment of response to CRT, this figure may rise.

Long-term outcome of patients with complete pathologic response after neoadjuvant chemoradiation for cT3 rectal cancer: implications for local excision surgical strategies

BACKGROUND

Neoadjuvant chemoradiotherapy (CRT) followed by radical surgery including total mesorectal excision (TME) is standard treatment in patients with locally advanced rectal cancer. Emerging data indicate that patients with complete pathologic response (ypCR) after CRT have favorable outcome, suggesting the possibility of less invasive surgical treatment. We analyzed long-term outcome of cT3 rectal cancer treated by neoadjuvant CRT in relation to ypCR and type of surgery.

METHODS

The study population comprised 139 patients (93 men, 46 women; median age 62 years) with cT3N0-1M0 mid and distal rectal adenocarcinoma treated by CRT and surgery (110 TME and 29 local excision) at our institution between 1996 and 2008. At pathology, ypCR was defined as no residual cancer cells in the primary tumor.

RESULTS

Tumors of 42 patients (30.2%) were classified as ypCR. After a median follow-up of 55.4 months, comparing patients with ypCR to patients with no ypCR, 5-year disease-specific survival was 95.8% versus 78.0% (P = 0.004), and 5-year disease-free survival was 90.1% vs. 64.0% (P = 0.004). In patients with ypCR, no statistically significant outcome difference was observed between TME and local excision. In patients treated by local excision, comparing patients with ypCR to patients with no ypCR, 5-year disease-free survival was 100% vs. 65.5% (P = 0.024), and 5-year local recurrence-free survival was 92.9% vs. 66.7% (P = 0.047).

CONCLUSIONS

With retrospective analysis limitations, our data confirm favorable long-term outcome of cT3 rectal cancer with ypCR after CRT and warrant clinical trials exploring local excision surgical strategies.

The prognostic value of grade of regression and oncocytic change in rectal adenocarcinoma treated with neo-adjuvant chemoradiotherapy

BACKGROUND

Pathological staging and regression grading may affect the clinical outcome in rectal carcinoma patients treated with neoadjuvant chemoradiation (NACRT). Oncocytic change (OC) has also been described in the residual tumor. This study assesses the correlation of degree of pathological response and OC with clinical outcome.

METHODS

Seventy-five cases of rectal adenocarcinoma undergoing NACRT followed by surgery were retrospectively analyzed for preoperative and post-operative staging, degree of tumor response to NACRT using the Dworak Regression score (DR) and Tumor Regression Grading (TRG) systems, as well as the proportion of cells showing OC. These parameters were correlated with overall survival (OS) and disease-free survival (DFS).

RESULTS

Significant correlation was found between post-operative T and N stage and OS (P = 0.005 and 0.002, respectively); and post-operative and preoperative T stage with DFS (P = 0.002 and 0.02, respectively). Grouping patients by TRG scores (TRG1-3 vs TRG4-5) also proved to be a significant independent prognosticator for DFS (P < 0.001). The DR score groups and OC (<35% vs. >35%) were not statistically significant predictors of clinical outcome.

CONCLUSIONS

Post-NACRT T and N staging and the TRG system are important prognostic indicators. The presence and extent of OC needs to be better understood and further investigated.

Transanal endoscopic microsurgery for residual rectal cancer after neoadjuvant chemoradiation therapy is associated with significant immediate pain and hospital readmission rates

BACKGROUND

Transanal endoscopic microsurgery may represent appropriate diagnostic and therapeutic procedure in selected patients with distal rectal cancer following neoadjuvant chemoradiation. Even though this procedure has been associated with low rates of postoperative complications, patients undergoing neoadjuvant chemoradiation seem to be at increased risk for suture line dehiscence. In this setting, we compared the clinical outcomes of patients undergoing transanal endoscopic microsurgery with and without neoadjuvant chemoradiation.

METHODS

Thirty-six consecutive patients were treated by transanal endoscopic microsurgery at a single institution. Twenty-three patients underwent local excision after neoadjuvant chemoradiation therapy for rectal adenocarcinoma, and 13 patients underwent local excision without any neoadjuvant treatment for benign and malignant rectal tumors. Chemoradiation therapy included 50.4 to 54 Gy and 5-fluorouracil-based chemotherapy. All patients underwent transanal endoscopic microsurgery with primary closure of the rectal defect. Complications (immediate and late) and readmission rates were compared between groups.

RESULTS

Overall, median hospital stay was 2 days. Immediate (30-d) complication rate was 44% for grade II/III complications. Patients undergoing neoadjuvant chemoradiation therapy were more likely to develop grade II/III immediate complications (56% vs 23%; P = .05). Overall, the 30-day readmission rate was 30%. Wound dehiscence was significantly more frequent among patients undergoing neoadjuvant chemoradiation therapy (70% vs 23%; P = .03). Patients undergoing neoadjuvant chemoradiation therapy were at significantly higher risk of requiring readmission (43% vs 7%; P = .02).

CONCLUSION

Transanal local excision with the use of endoscopic microsurgical approach may result in significant postoperative morbidity, wound dehiscence, and readmission rates, in particular, because of rectal pain secondary to wound dehiscence. In this setting, the benefits of this minimally invasive approach either for diagnostic or therapeutic purposes become significantly restricted to highly selected patients that can potentially avoid a major operation but will still face a significantly morbid and painful procedure.

Complete clinical response after neoadjuvant chemoradiation for distal rectal cancer

Multimodality treatment of rectal cancer, with the combination of radiation therapy, chemotherapy, and surgery has become the preferred approach to locally advanced rectal cancer. The use of neoadjuvant chemoradiation therapy (CRT) has resulted in reduced toxicity rates, significant tumor downsizing and downstaging, better chance of sphincter preservation, and improved functional results. A proportion of patients treated with neoadjuvant CRT may ultimately develop complete clinical response. Management of these patients with complete clinical response remains controversial and approaches including radical resection, transanal local excision, and observation alone without immediate surgery have been proposed. The use of strict selection criteria of patients after neoadjuvant CRT has resulted in excellent long-term results with no oncological compromise after observation alone in patients with complete clinical response. Recurrences are detectable by clinical assessment and frequently amenable to salvage procedures.