Residual Mesorectal Lymph Node Involvement Following Neoadjuvant Combined-Modality Therapy: Rationale for Radical Resection?

Imaging and Metabolic Diagnostic Methods in the Stage Assessment of Rectal Cancer

Rectal cancer (RC) is a prevalent malignancy with significant morbidity and mortality rates. The accurate staging of RC is crucial for optimal treatment planning and patient outcomes. This review aims to summarize the current literature on imaging and metabolic diagnostic methods used in the stage assessment of RC. Various imaging modalities play a pivotal role in the initial evaluation and staging of RC. These include magnetic resonance imaging (MRI), computed tomography (CT), and endorectal ultrasound (ERUS). MRI has emerged as the gold standard for local staging due to its superior soft tissue resolution and ability to assess tumor invasion depth, lymph node involvement, and the presence of extramural vascular invasion. CT imaging provides valuable information about distant metastases and helps determine the feasibility of surgical resection. ERUS aids in assessing tumor depth, perirectal lymph nodes, and sphincter involvement. Understanding the strengths and limitations of each diagnostic modality is essential for accurate staging and treatment decisions in RC. Furthermore, the integration of multiple imaging and metabolic methods, such as PET/CT or PET/MRI, can enhance diagnostic accuracy and provide valuable prognostic information. Thus, a literature review was conducted to investigate and assess the effectiveness and accuracy of diagnostic methods, both imaging and metabolic, in the stage assessment of RC.

Characteristics of pathologic complete response for locally advanced rectal cancer

BACKGROUND

Neoadjuvant chemoradiation (NACRT) is the standard of care for locally advanced rectal cancers. The purpose of this study was to determine patient and tumor factors associated with a pathologic complete response (pCR).

METHODS

The National Surgical Quality Improvement Program proctectomy-targeted database was utilized to identify all patients from 2016 to 2020 who underwent NACRT followed by proctectomy with curative intent for T3-4N0-2 rectal cancers.

RESULTS

A total of 1891 patients were included, of which 253 (13.4%) demonstrated a pCR. Pretreatment N0 staging was associated with a higher rate of pCR (18.9%) when compared to N1 (6.7%) and N2 (6.7%) (p < 0.0001). Patients clinically staged at T3N0 had the highest rate of pCR (19.5%). Gender, age, race, weight, smoking status, and tumor height were not associated with pCR.

CONCLUSIONS

Patients with cN0 disease were more likely to experience a pCR compared to cN1-2 patients. Tumor height relative to anal verge or patient demographics were not associated with pCR.

New Opportunities for Minimizing Toxicity in Rectal Cancer Management

Advances in multimodal management of locally advanced rectal cancer (LARC), consisting of preoperative chemotherapy and/or radiotherapy followed by surgery with or without adjuvant chemotherapy, have improved local disease control and patient survival but are associated with significant risk for acute and long-term morbidity. Recently published trials, evaluating treatment dose intensification via the addition of preoperative induction or consolidation chemotherapy (total neoadjuvant therapy [TNT]), have demonstrated improved tumor response rates while maintaining acceptable toxicity. In addition, TNT has led to an increased number of patients achieving a clinical complete response and thus eligible to pursue a nonoperative, organ-preserving, watch and wait approach, thereby avoiding toxicities associated with surgery, such as bowel dysfunction and stoma-related complications. Ongoing trials using immune checkpoint inhibitors in patients with mismatch repair-deficient tumors suggest that this subgroup of patients with LARC could potentially be treated with immunotherapy alone, sparing them the toxicity associated with preoperative treatment and surgery. However, the majority of rectal cancers are mismatch repair-proficient and less responsive to immune checkpoint inhibitors and require multimodal management. The synergy noted in preclinical studies between immunotherapy and radiotherapy on immunogenic tumor cell death has led to the design of ongoing clinical trials that explore the benefit of combining radiotherapy, chemotherapy, and immunotherapy (mainly of immune checkpoint inhibitors) and aim to increase the number of patients eligible for organ preservation.

Tumor Volume as Predictor of Pathologic Complete Response Following Neoadjuvant Chemoradiation in Locally Advanced Rectal Cancer

PURPOSE

Neoadjuvant chemoradiation followed by surgery is the current standard of care in the treatment of locally advanced rectal cancer. Those who achieved pathologic complete response, following this standard of care, complete pathologic response (pCR) had better outcome. Until now there are no reliable clinical parameters to predict this response. The purpose of the study was to evaluate whether tumor volume may serve as a predictive factor in patients treated with neoadjuvant chemoradiotherapy.

MATERIALS AND METHODS

Between September 2015 and September 2019, patients diagnosed with stage IIA to IIIC rectal adenocarcinoma, who were treated with neoadjuvant chemoradiation, were enrolled to this study. All patients underwent rectal ultrasound, pelvic magnetic resonance imaging, fluorodeoxyglucose-positron emission tomography-computed tomography and the diagnosis was confirmed by pathology report. Radiation therapy was consisted of 50 Gy delivered to the tumor site, 2 Gy a day, 5 times a week and to the pelvic lymph nodes for a total of 45 Gy in 1.8 Gy a day, 5 times a week. The gross tumor volume (GTV) was contoured by radiation oncology expert, reviewed by radiology and nuclear medicine expert and approved by radiation therapy tumor board. Chemotherapy was consisted of either capecitabine 875 mg/m2 twice a day or continuous. IV infusion of 5 fluorouracil 375 mg/m2 for 4 consecutive days in a 3 weeks apart. Operation, either low anterior or abdominoperineal resection was carried out 6 to 8 weeks following completion of treatment. Patients were assigned to either complete pathologic response (pCR) or non-pCR groups. GTV, among other clinical and treatment parameters, were evaluated for prediction of pCR. Statistical methods included independent t test, logistic regression, area under the curve-receiver operating characteristic, Bayesian independent statistics and multilayer perceptron model.

RESULTS

One hundred ninety-three patients were enrolled to this study, 6 were excluded due to metastatic disease detected at the time of operation. Seventy had stage II and 117 had stage III. Forty-four of 187 (23.5%) patients achieved pCR and 143 patients had either partial or no response/progressive disease. Among the 44 pCR group, 21 had stage II and 23 had stage III disease. Treatment interruption, defined as either a delay of up to 1 week in radiation, and a dose reduction to 75%, was occurred in 42 patients. Sex, ethnicity, distance from anal verge to tumor, height, weight, age, delivered radiation dose, radiotherapy techniques, clinical T and N stage and GTV were evaluated for prediction of pCR. GTV at the volume of <39.5 cm3 was the only significant predictive factor to detect pCR by logistic regression model (P<0.01) and by Bayesian independent test (P=0.026). Area under the receiver operating characteristic curve of GTV <39.5 cm3 showed area under the curve of 0.715 (P=0.009) for stage II and area under the curve of 0.62 (P>0.05) for stage III.

CONCLUSION

GTV may serve as a predictive factor for achieving pCR in locally advanced rectal cancer after neoadjuvant chemoradiotherapy.

Neoadjuvant Therapy and Surgery in Rectal Adenocarcinoma: Analysis of Patients with Complete Tumor Remission

Introduction: the standard treatment for locally advanced extra-peritoneal rectal adenocarcinoma, consists of neoadjuvant treatment with radiotherapy and chemotherapy followed by total mesorectal excision.

Objective: evaluate, retrospectively, the patients submitted to neoadjuvant therapy and surgery that presents with total remission of the lesion in the anatomopathological examination.

Methods: between 2000 and 2010, 212 patients underwent surgery at the Coloproctology Unit at DMAD at FCM–UNICAMP. They were grouped as: rectosigmoidectomy and colorectal anastomosis (n = 54), rectosigmoidectomy with coloanal anastomosis (n = 41), 114 abdominoperineal resection of the rectum (n = 114) and other (n = 3).

Results: thirty (14.2%) patients (mean age 57.6 years; 60% males) showed complete remission of the rectal lesion. 4 (13.3%) had compromised lymph nodes and/or lymphatic invasion

At follow-up (mean 51.9 months), 4 (13.3%) presented with local recurrence (one patient) or distant metastases (two patients had liver metastasis, one had liver and lung, and one had bone metastasis). The mean survival was 86.7%.

Conclusion: patients with a complete tumor response show ed an increased survival rate, however, the same patients without evidence of residual tumors could develop local recurrence or distant metastases on a later follow-up.

Pathological Tumor Regression Grade Classifications in Gastrointestinal Cancers: Role on Patients' Prognosis

Preoperative chemotherapy or combined radiotherapy and chemotherapy (CRT), followed by surgery, represents the standard approach for locally advanced esophageal, gastric, and rectal carcinomas. To adequately evaluate the effects of neoadjuvant CRT in the resection specimens, several histopathologic tumor regression grade (TRG) scoring systems have been introduced into clinical practice. The primary goal of these TRG systems relies on a correct prognostic stratification of patients in the attempt to help clinical decision-making and influence surgical strategies, postoperative adjuvant therapies, and surveillance intensity. However, most TRG systems suffer from poor reproducibility and low interobserver concordance rates. Many efforts have been made in the identification of alternative, robust, simple, and universally accepted TRG scoring systems, which would help in the comparison of different treatment strategies and in the standardization of multimodal therapies. The aim of this review is to analyze the most commonly used TRG systems in gastrointestinal cancers highlighting their pitfalls and usefulness, depending on the tumor type.

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.

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.

An observational study of extending FOLFOX chemotherapy, lengthening the interval between radiotherapy and surgery, and enhancing pathological complete response rates in rectal cancer patients following preoperative chemoradiotherapy

INTRODUCTION

Patients with rectal cancer who exhibit a pathologic complete response to preoperative concurrent chemoradiotherapy have excellent oncologic outcomes. In this study, we evaluated the potential advantages of adding oxaliplatin to preoperative fluoropyrimidine-based chemoradiotherapy administered in rectal cancer patients.

METHODS

A total of 78 patients with rectal cancer were enrolled. Patients were administered chemoradiotherapy, which comprised radiotherapy and chemotherapy involving a 5-fluorouracil, leucovorin, and oxaliplatin regimen every 2 weeks. Surgery was performed 10-12 weeks after radiotherapy completion. Tumor regression, adverse events, surgical complications, and short-term clinical outcomes were recorded.

RESULTS

Two patients were excluded because of incomplete radiotherapy treatment or refusal of surgery. Eventually, 76 patients underwent total mesorectal excision and no perioperative mortality was observed. Of these, 20 patients (25.6%) developed grade 3 or 4 toxicity during concurrent chemoradiotherapy. Among the 76 patients who underwent surgery, 24 (31.6%) patients achieved a pathologic complete response. The sphincter preservation rate was 96.1% (73/76) in all patients and 92.2% (39/42) in patients with tumors located less than 5 cm from the anal verge. The 2-year overall and disease-free survivals were 94% and 87.4%, respectively.

CONCLUSION

The intensified multimodality therapy was well tolerated in our cohort and resulted in a considerably high pathologic complete response rate. Regardless of favorable short-term clinical outcomes, long-term oncologic outcomes will be closely monitored among the patients with a pathologic complete response.

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.

Definitive Chemoradiotherapy ("Watch-and-Wait" Approach)

Preoperative chemoradiotherapy (CRT) followed by total mesorectal excision has been the standard of care for locally advanced patients with rectal cancer. Some patients achieve a pathologic complete response (pCR) to CRT and the oncologic outcomes are particularly favorable in this group. The role of surgery in patients with a pCR is now being questioned as radical rectal resection is associated with significant morbidity and long-term effects on quality of life. In an attempt to better tailor therapy, there is an interest in a "watch-and-wait" approach in patients who have a clinical complete response (cCR) after CRT with the goal of omitting surgery and allowing for organ preservation. However, a cCR does not always indicate a pCR, and improved clinical and imaging modalities are needed to better predict which patients have achieved a pCR and therefore can safely undergo a "watch-and-wait" approach. This article reviews the current data on nonoperative management and on-going controversies associated with this approach.

Optimal therapy for resectable rectal cancer

A lot can be gained by improving our understanding of the optimal sequence of existing therapies in rectal cancer, with the more difficult task of balancing the morbidity of recurrence with the morbidity of prescribed therapies that are particularly toxic owing to tumour location. This review aims to highlight a recent shift in treatment strategies in the opposite direction, with a focus on earlier, more intense systemic treatments with reduced local therapies. Understanding the rationale for and evidence to support this shift will help identify gaps, shape future trials, and ultimately answer the question of whether this is indeed the right path to follow with regards to maintaining local control rates and long-term outcomes for patients, and improving distal disease control and local treatment-related morbidities without compromising quality of life.

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 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.

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.

Neoadjuvant therapy followed by local excision and two-stage total mesorectal excision: a new strategy for sphincter preservation in locally advanced ultra-low rectal cancer

BACKGROUND

With the increased usage of neoadjuvant chemoradiotherapy, improved surgical technique and stapling devices, sphincter-preserving resection has become more frequent for patients with rectal cancer. However, as for locally advanced ultra-low rectal cancer, sphincter-preservation is still facing an enormous challenge.

OBJECTIVE

To introduce an NLT strategy of sphincter-preservation-neoadjuvant therapy (NT) followed by local excision (LE) and two-stage total mesorectal excision (TME)-into the treatment of locally advanced ultra-low rectal cancer (lesions with anal sphincter invasion).

METHODS

From October 2010 to October 2011, nine patients with locally advanced rectal cancer located less than 3 cm from the anal verge were treated by the NLT strategy. All patients had shown good clinical response to NT. The LE procedure was carried transanally 6-8 weeks after completion of the NT. TME was performed to dissect mesorectal lymph nodes 4-6 weeks after LE.

RESULTS

Of the nine patients, the lesion was assessed as T2 in two, T3 in five, and T4 in two before NT, and lymph node metastasis was detected in five patients. The median distance from the tumor to the anal verge was 2.5 cm (range: 1-3 cm). The median follow-up was 27 months (range: 24-34 months). No distant metastasis was detected. Only one patient (11.1%) developed local recurrence at 12 months post-operatively and then underwent abdomino-perineal resection. The remaining eight patients had preserved long-term continence and the median Wexner score at two years post-operation was 4 (range: 2-6).

CONCLUSION

The new NLT strategy can achieve sphincter-preservation in some patients with ultra-low rectal cancer, with favorable oncological outcome and preservation of normal anal sphincter function.

Less than 12 nodes in the surgical specimen after total mesorectal excision following neoadjuvant chemoradiation: it means more than you think!

BACKGROUND

A minimum of 12 examined lymph nodes (LN) is recommended to ensure adequate staging and oncologic resection of patients undergoing proctectomy for rectal adenocarcinoma. However, a decreased number of LN is not unusual in patients receiving neoadjuvant chemoradiation.

PURPOSE

We hypothesized that a decreased number of LN in the proctectomy specimen of these patients may be an indicator of tumor response and be associated with improved prognosis.

METHODS

A single-center colorectal cancer database was queried for c-stage II-III rectal cancer patients undergoing neoadjuvant chemoradiation followed by proctectomy between 1997 and 2007. Patients were categorized into two groups according to the number of LN retrieved from the proctectomy specimen: <12 LN versus ≥12 LN. Groups were compared with respect to demographics, tumor and treatment characteristics, and the following oncologic outcomes: overall-survival (OS), cancer-specific-mortality (CSM), cancer-free-survival (CFS), distant (DR), and local recurrences (LR).

RESULTS

The query returned 237 patients. There were 173 (73 %) males, and the median age was 57 years [interquartile range (IQR) 49-66 years]. The median number of LN retrieved was 15 (IQR 10-23) and 70 (30 %) patients had less than 12 nodes examined. The <12 nodes group was older [60 (IQR 51-71 years) vs. 55 (IQR 48-65 years), p = 0.009] and had more pathologic complete responders (36 vs. 19 %, p = 0.01). No <12 nodes patient experienced a LR, whereas the 5-year LR rate was 11 % in the ≥12 nodes group (p = 0.004). Other oncologic outcomes were not significantly different.

CONCLUSIONS

Retrieval of less than 12 nodes in the proctectomy specimen of rectal cancer patients treated with neoadjuvant chemoradiation does not affect OS, CSM, CFS, or DR and may be a marker of higher tumor response and, consequently, decreased LR rate.

Treatment of locally advanced rectal cancer: Controversies and questions

Rectal cancers extending through the rectal wall, or involving locoregional lymph nodes (T3/4 or N1/2), have been more difficult to cure. The confines of the bony pelvis and the necessity of preserving the autonomic nerves makes surgical extirpation challenging, which accounts for the high rates of local and distant relapse in this setting. Combined multimodality treatment for rectal cancer stage II and III was recommended from National Institute of Health consensus. Neoadjuvant chemoradiation using fluoropyrimidine-based regimen prior to surgical resection has emerged as the standard of care in the United States. Optimal time of surgery after neoadjuvant treatment remained unclear and prospective randomized controlled trial is ongoing. Traditionally, 6-8 wk waiting period was commonly used. The accuracy of studies attempting to determine tumor complete response remains problematic. Currently, surgery remains the standard of care for rectal cancer patients following neoadjuvant chemoradiation, whereas observational management is still investigational. In this article, we outline trends and controversies associated with optimal pre-treatment staging, neoadjuvant therapies, surgery, and adjuvant therapy.

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.

Complete clinical response after neoadjuvant chemoradiation therapy for distal rectal cancer: characterization of clinical and endoscopic findings for standardization

BACKGROUND

Complete tumor regression may develop after neoadjuvant chemoradiation therapy for distal rectal cancer. Studies have suggested that selected patients with complete clinical response may avoid radical surgery and close surveillance may provide good outcomes with no oncologic compromise. However, definition of complete clinical response is often imprecise and may vary between different studies. The aim of this study is to provide a clear definition for a complete clinical response after neoadjuvant chemoradiation therapy in patients with distal rectal cancer in addition to actual endoscopic videos from patients managed nonoperatively.

METHODS

Patients with nonmetastatic distal rectal cancer treated by neoadjuvant chemoradiation therapy, including 50.4 Gy and concomitant 5-fluorouracil and leucovorin, were assessed for tumor response at least 8 weeks after chemoradiation therapy completion. Complete and incomplete clinical responses were defined based on clinical and endoscopic findings. Patients with complete clinical response were not immediately operated on and were closely followed. Early and late endoscopic findings were recorded.

RESULTS

Definition of a complete clinical response should be based on very strict clinical and endoscopic criteria. The finding of any residual superficial ulceration, irregularity, or nodule should prompt surgical attention, including transanal full-thickness excision or even a radical resection with total mesorectal excision. Standard or incisional biopsies should be avoided in this setting. Complete clinical responders should harbor no more than whitening of the mucosa, teleangiectasia with mucosal integrity to be considered for a nonoperative approach. In the presence of these findings, regularly scheduled reassessments may provide a safe alternative to these patients with early detection of recurrent disease.

CONCLUSION

Strict definition of the clinical and endoscopic findings of patients experiencing complete clinical response after neoadjuvant chemoradiation therapy may provide a useful tool for the understanding of outcomes of patients managed with no immediate surgery allowing standardization of classifications and comparison between the experiences of different institutions.

Is local excision after complete pathological response to neoadjuvant chemoradiation for rectal cancer an acceptable treatment option?

PURPOSE

The role of local excision in patients with good histological response to neoadjuvant chemoradiation for locally advanced rectal cancer is unclear, mainly because of possible regional nodal involvement. This study aims to evaluate the correlation between pathological T and N stages following neoadjuvant chemoradiation for locally advanced rectal cancer and the outcome of patients with mural pathological complete response undergoing local excision.

METHODS

This investigation was conducted as a retrospective analysis. Between January 1997 and December 2007, 320 patients with T3 to 4Nx, TxN+ or distal (≤ 6 cm from the anus) T2N0 rectal cancer underwent neoadjuvant concurrent chemoradiation followed by surgery. Radiotherapy was standard and chemotherapy consisted of common fluoropyrimidine-based regimens.

RESULTS

After chemoradiation, 93% patients had radical surgery, 6% had local excision, and 3% did not have surgery. In the 291 patients undergoing radical surgery, the pathological T stage correlated with the N stage (P = .036). We compared the outcome of patients with mural complete pathological response (n = 37) who underwent radical surgery (group I) and those (n = 14) who had local excision only (group II). With a median follow-up of 48 months, 4 patients in group I had a recurrence and none in group II had a recurrence; one patient died in group I and none died in group II. Disease-free survival, pelvic recurrence-free survival, and overall survival rates were similar in both groups.

CONCLUSION

In this retrospective study, nodal metastases were rare in patients with mural complete pathological response following neoadjuvant chemoradiation (3%), and local excision did not compromise their outcome. Therefore, local excision may be an acceptable option in these patients.

Controversial aspects of rectal cancer surgery following preoperative chemoradiation

The role of surgery in the loco-regional control of adenocarcinoma of the rectum is being increasingly challenged by the good response rates of neoadjuvant oncological treatment. This review represents an opinion paper outlining well-established choices and new trends in surgical intervention, unresolved difficulties of local and regional staging of rectal malignancy and accurate assessment of tumour response to preoperative downstaging chemoradiation. The influence of preoperative chemoradiation on subsequent surgical strategy is discussed highlighting several controversial aspects of surgical management both when the tumour fails to respond and appears to be irresectable and when complete clinical response is observed.

Management of the hepatic lymph nodes during resection of liver metastases from colorectal cancer: a systematic review

BACKGROUND

Hepatic lymph node involvement is generally considered a contraindication for liver resection performed for colorectal liver metastases. However, some advocate hepatic lymphadenectomy in the presence of macroscopic involvement and others routine lymphadenectomy. The aim of this review is to assess the role of lymphadenectomy in resection of liver metastases from colorectal cancer.

METHODS

Medline, Embase and Central databases were searched using a formal search strategy. Trials with survival data with a minimum follow-up of 1 year were considered for inclusion. Meta-analysis was performed using Revman.

RESULTS

A total of 4230 references were identified. Ten reports of nine studies including 926 patients qualified for the review. The prevalence of nodal metastases after routine lymphadenectomy was 16.3%. The overall 3-year and 5-year survival rates in node-positive patients were 9/151 (11.3%) and 2/137 (1.5%), respectively, compared to 3-year and 5-year survival rates of 424/787 (53.9%) and 246/767 (32.1%) in node-negative patients. The odds ratios for 3-year and 5-year survivals in node positive disease compared to node-negative disease were 0.12 (95% CI 0.06 to 0.24) and 0.08 (95% CI 0.03 to 0.22). There was no randomized controlled trial which assessed the survival benefit of routine or "selective" lymphadenectomy.

CONCLUSION

Currently, there is no evidence of survival benefit for routine or selective lymphadenectomy. Survival rates are low in patients with positive lymph nodes draining the liver irrespective of whether they are detected by routine lymphadenectomy or by macroscopic involvement. Further trials in this patient group are required.

Downstaging after chemoradiotherapy for locally advanced rectal cancer: is there more (tumor) than meets the eye?

PURPOSE

Preoperative chemoradiotherapy can lead to pathologic complete response of rectal cancer. This study was designed to determine the relationship between postchemoradiotherapy pathologic T stage (ypT stage) and nodal metastases and to evaluate whether pathologic complete response of the primary tumor results in sterilization of mesorectal lymph nodes.

METHODS

Clinicopathological data from 1997 to 2007 of a prospectively maintained colorectal cancer database were examined. Inclusion criteria were patients with extraperitoneal rectal cancer who underwent preoperative chemoradiotherapy and subsequent radical resection. Statistical analysis was performed by use of Kruskall-Wallis and Wilcoxon rank-sum tests.

RESULTS

Two hundred forty-two patients were identified (73.1% male, median age, 57 y (range, 36-85 y)). Data regarding preoperative chemoradiotherapy were available for 177 patients (73.1%). The median dose of radiotherapy was 5040 cGy (3060-6100 cGy). The mean preoperative radiotherapy dose and interval between chemoradiotherapy and surgery are similar when stratified by ypT stage (P = .55 and P = .72, respectively). Low anterior resection was performed in 174 patients (71.6%), and the remainder underwent abdominoperineal resection. A mural pathologic complete response was achieved in 62 patients (25.6%). In this pathologic complete-response group, positive lymph nodes were found in 2 patients (3.2%). The rate of metastatic lymph nodes increased as ypT stage increased (ypT1 = 11.1%, ypT2 = 29.2%, ypT3 = 37.3%).

CONCLUSION

Patients with a mural pathologic complete response have a low rate of positive lymph nodes. These findings may have implications for the management strategies of these patients, including the use of local resection or a watch-and-wait policy. When the response to chemoradiotherapy is not complete, radical surgery should remain the treatment based on high rates of lymph node involvement.

Surgical resection versus non-surgical treatment for hepatic node positive patients with colorectal liver metastases

BACKGROUND

Involvement of hepatic lymph node in patients with colorectal liver metastases is associated with poor prognosis.

OBJECTIVES

To determine the benefits and harms of curative liver resection with lymphadenectomy versus other treatments for colorectal liver metastases with hepatic node involvement.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and LILACS until September 2009 for identifying the randomised trials.

SELECTION CRITERIA

We considered only randomised clinical trials (irrespective of language, blinding, or publication status) comparing liver resection (alone or in combination with radiofrequency ablation or cryoablation) versus other treatments (neo-adjuvant chemotherapy, chemotherapy, or radiofrequency ablation) in patients with colorectal liver metastases with hepatic node involvement.

DATA COLLECTION AND ANALYSIS

Two authors independently identified trials for inclusion.

MAIN RESULTS

We were unable to identify any randomised clinical trial fulfilling the inclusion criteria of this review. We were also unable to identify any quasi-randomised or cohort studies, which could meaningfully answer this important issue.

AUTHORS' CONCLUSIONS

There is no evidence in the literature to assess the role of surgery versus other treatments for patients with colorectal liver metastases with hepatic node involvement. High quality randomised clinical trials are feasible and are necessary to determine the optimal management of patients with colorectal liver metastases with hepatic node involvement.

Tumor volume changes assessed by three-dimensional magnetic resonance volumetry in rectal cancer patients after preoperative chemoradiation: the impact of the volume reduction ratio on the prediction of pathologic complete response

PURPOSE

The aim of this study was to determine the correlation between tumor volume changes assessed by three-dimensional (3D) magnetic resonance (MR) volumetry and the histopathologic tumor response in rectal cancer patients undergoing preoperative chemoradiation therapy (CRT).

METHODS AND MATERIALS

A total of 84 patients who underwent preoperative CRT followed by radical surgery were prospectively enrolled in the study. The post-treatment tumor volume and tumor volume reduction ratio (% decrease ratio), as shown by 3D MR volumetry, were compared with the histopathologic response, as shown by T and N downstaging and the tumor regression grade (TRG).

RESULTS

There were no significant differences in the post-treatment tumor volume and the volume reduction ratio shown by 3D MR volumetry with respect to T and N downstaging and the tumor regression grade. In a multivariate analysis, the tumor volume reduction ratio was not significantly associated with T and N downstaging. The volume reduction ratio (>75%, p = 0.01) and the pretreatment carcinoembryonic antigen level (< or =3 ng/ml, p = 0.01), but not the post-treatment volume shown by 3D MR (< or = 5 ml), were, however, significantly associated with an increased pathologic complete response rate.

CONCLUSION

More than 75% of the tumor volume reduction ratios were significantly associated with a high pathologic complete response rate. Therefore, limited treatment options such as local excision or simple observation might be considered after preoperative CRT in this patient population.

Treatment for patients with rectal cancer and a clinical complete response to neoadjuvant therapy: a decision analysis

PURPOSE

A clinical complete response to neoadjuvant therapy occurs in a subset of patients with rectal cancer. Management of these patients is controversial and tension exists between the recurrence risk with observation, and the impact of surgery on quality-of-life. Therefore, the objective was to develop a decision-analytic model to evaluate the relative benefits of surgery vs. observation in rectal cancer patients who achieve clinical complete response after neoadjuvant chemoradiation.

METHODS

Clinically relevant inputs and events, including the ability to identify complete responders, likelihood of relapse and of salvage surgery after relapse, and utilities for each health state, were simulated by use of a Markov state-transition model. Transition probabilities and health-state utilities were derived from the literature and expert consensus. One-way and two-way sensitivity analyses were performed to assess the robustness of model results to assumptions. The primary outcome was quality-adjusted life expectancy.

RESULTS

In the base-case analysis, the quality-adjusted life expectancy with surgery exceeded observation (5.63 vs. 5.34 quality-adjusted life-years). Sensitivity analysis demonstrated that observation was preferred to surgery if the ability to correctly identify patients with true complete responses exceeded 58 percent, if quality-of-life after surgery was poor (utility <0.81), or if the relative reduction in recurrence risk with surgery was <43 percent when compared with observation.

CONCLUSIONS

Our model outlines the issues associated with surgery vs. observation, and suggests that surgery is beneficial for the average patient with rectal cancer with a clinical complete response after neoadjuvant therapy. Current limitations in the clinical assessment of patient response to chemoradiation constitute an important factor influencing our results, and therefore warrant further investigation.

The correlation between tumour regression grade and lymph node status after chemoradiation in rectal cancer

OBJECTIVE

To determine the correlation between tumour response to preoperative RCTX and lymph node status, an established parameter of clinical outcome.

METHOD

After IRB approval, 86 consecutive rectal cancer patients who received preoperative RCTX were identified. Fifty seven were males. Mean age 62 years. Preoperative staging by ultrasound was available in 60 patients. Radiotherapy consisted of (40-60 g) and chemotherapy of 5-FU infusion (1500 mg/m(2) week), assessed using Dworak's system.

RESULTS

Tumour response according to Tumor regression grade (TRG) were: TRG 0: 8 (9.3%); TRG 1: 15 (17.4%); TRG 2: 14 (16.2%); TRG 3: 31 (36%); TRG 4: 18 (20%). Eighteen patients had tumour stage 0 (20.9%); while 8 (9.2%), 28 (32.1%), 30 (34.5%) and three had tumours stages 1, 2, 3 and 4 respectively. Evaluation of nodal status revealed no involvement in 65 patients (N0), and positive nodes in 21 (14 N1, 7 N2). Response to RCTX was significantly associated with node stage, hence individuals without node involvement (N0) had 66% of positive tumour response (TRG 4), while individuals with node metastasis had less response to RCTX (TRG 0, 1 and 2) 35% N1 and 14% for N2 (P = 0.007). Node status was independently associated to poor response to preoperative RCTX, even after adjusting for tumour stage, age and gender (OR 0.02, 95% CI 0.0009-0.67).

CONCLUSION

Tumour shrinkage by preoperative RCTX appears to correlate with lymph node metastasis suggesting that neoadjuvant RCTX may have a positive impact in overall patient survival.

A simplified tumor regression grade correlates with survival in locally advanced rectal carcinoma treated with neoadjuvant chemoradiotherapy

BACKGROUND

Locally advanced rectal cancer is frequently treated with neoadjuvant chemoradiotherapy to reduce local recurrence and possibly improve survival. The tumor response to chemoradiotherapy is variable and may influence the prognosis after surgery. This study assessed tumor regression and its influence on survival in patients with rectal cancer treated with chemoradiotherapy followed by curative surgery.

METHODS

One hundred twenty-six patients with locally advanced rectal cancer (T3/T4 or N1/N2) were treated with chemoradiotherapy followed by total mesorectal excision. Patients received long-course radiotherapy (50 Gy in 25 fractions) in combination with 5-flourouracil over 5 weeks. By means of a standardized approach, tumor regression was graded in the resection specimen using a 3-point system related to tumor regression grade (TRG): complete or near-complete response (TRG1), partial response (TRG2), or no response (TRG3).

RESULTS

The 5-year disease-free survival was 72% (median follow-up 37 months), and 7% of patients had local recurrence. Chemoradiotherapy produced downstaging in 60% of patients; 21% of patients experienced TRG1. TRG1 correlated with a pathological T0/1 or N0 status. Five-year disease-free survival after chemoradiotherapy and surgery was significantly better in TRG1 patients (100%) compared with TRG2 (71%) and TRG3 (66%) (P = .01).

CONCLUSION

Tumor regression grade measured on a 3-point system predicts outcome after chemoradiotherapy and surgery for locally advanced rectal cancer.

Long-term results of transanal excision after neoadjuvant chemoradiation for T2 and T3 adenocarcinomas of the rectum

INTRODUCTION

Traditionally, selected early distal rectal cancers have been considered for treatment by transanal excision (TAE) with acceptable oncologic results. With the frequent use of neoadjuvant chemoradiation (NCR) for the treatment of locally advanced rectal cancer, there is growing interest in the application of TAE for such lesions. We report our experience of TAE for T2 and T3 rectal cancers following NCR.

MATERIAL AND METHODS

Between July 1994 and August 2006, 44 patients were identified as having undergone full-thickness TAE of pretreatment ultrasound-staged T2 and T3 rectal cancers that were treated with NCR. Fifteen patients were deemed medically unfit for radical resection, and 29 would have required abdominoperineal resection but were opposed to colostomy.

RESULTS

Our patient population consisted of 26 men and 18 women, with a median age of 69 (range, 43-89) and a median follow up of 64 months (6-153). Thirty-one patients had a clinical complete response (cCR) to NCR of which 19 (61%) had a pathologic CR (pCR). Seven (16%) of 44 patients sustained disease recurrence of which two were local only, two local and systemic, and three systemic only. Only four (9%) patients had died of disease at current follow up. Overall 5-year survival rates for T2/T3N0 and T2/T3N1 patients were 84% and 81%, respectively. Five patients underwent radical resection immediately following TAE for either positive margins or residual cancer. There was minimal morbidity with no perioperative mortality associated with TAE.

CONCLUSIONS

TAE of T2 and T3 rectal cancers following NCR is a safe alternative to radical resection in a highly select group of patients for which recurrence and survival rates comparable to radical resection can be achieved. This study supports ongoing efforts to assess this approach in prospective, multi-center trials.

Prediction of rectal lymph node metastasis by pelvic computed tomography measurement

AIM

Rectal cancer staging represents a crucial step to select the best treatment for this tumour. Particularly after neo-adjuvant chemoradiotherapy (CRT), it may influence the surgical procedure (e.g. radical resection vs. local excision). The aim of this study was to determine the best lymph node size cut-off at computed tomography (CT) to predict nodal metastasis in rectal cancer patients with and without preoperative CRT.

METHODS

A consecutive series of patients operated on for primary mid-low rectal adenocarcinoma, all staged with pelvic CT scan, were subdivided as follows: those who underwent surgery alone treatment without CRT (Group A) and those who underwent preoperative CRT (Group B). All CT scans were re-viewed by a single radiologist and, based on the lymph node size, findings were compared with pathologic lymph node status (pN). At each lymph node size cut-off value, the following were calculated: accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). The best cut-off value was defined as having an accuracy >or=70% with the highest NPV.

RESULTS

The study population consisted of 162 patients: Group A (n=52) and Group B (n=110). Patients classified as pN-positive (n=45) had a higher number of and larger sized lymph nodes by CT scan than patients classified as pN-negative (n=117). The cut-off values with an accuracy >or=70% ranged between 7 and 11 mm in Group A and between 9 and 14 mm in Group B. The cut-off with the best NPV was 7 mm for Group A and 10mm for Group B.

CONCLUSIONS

Acknowledging the limitations of the dimensional criterion, lymph node size cut-off values found in our study may be useful for planning rectal cancer treatment using CT scan.

Predictive clinicopathologic factors for limited response of T3 rectal cancer to combined modality therapy

PURPOSE

The response of T3 rectal cancer to combined modality therapy (CMT) is highly predictive of long-term outcome following surgery. The aim of this study was to identify pretreatment factors associated with poor tumor response to neoadjuvant chemoradiation.

METHODS

A prospective institutional database at Memorial Sloan-Kettering Cancer Center was queried for endorectal ultrasound (ERUS) stage T3N0-2 rectal cancer patients, treated with CMT followed by surgical resection, between 1998 and 2003. Preoperative clinicopathologic factors determined by biopsy, ERUS, proctoscopy, and digital rectal examination were correlated with the degree of downstaging of the primary mural lesion (tumor downstaging) in response to neoadjuvant therapy. Associations were analyzed by chi-square, Kaplan-Meier, and logistic regression.

RESULTS

Of 274 patients, 51% obtained tumor downstaging in response to preoperative treatment, i.e., lower pathologic T-stage compared with pretreatment ERUS. Five-year recurrence-free survival was 89% in the cohort that obtained tumor downstaging compared with only 45% in the cohort that obtained no tumor downstaging. Factors significantly associated with limited or lack of tumor downstaging after CMT included: fixed tumor on digital rectal examination (p < 0.021), near-circumferential tumor (p < 0.011), tumor stenosis (p < 0.025), metastatic disease (p < 0.012), biopsy-proven poorly differentiated pathology (p < 0.002), and radial extension >2.5 mm on ERUS (p < 0.031). On multivariate analysis, deep radial extension on ERUS, metastatic disease, and poorly differentiated pathology were in each, independently associated with limited or lack of tumor downstaging.

CONCLUSIONS

Pretreatment evaluation with biopsy, proctoscopy, and ERUS can identify T3 rectal cancer patients unlikely to respond well to CMT. These patients may be considered for alternative protocols and their tumors studied to ascertain the molecular events responsible for resistance to chemoradiation.

Long-term results of laparoscopic treatment for advanced rectal cancer

BACKGROUND

The management of advanced rectal cancer has changed into a multidisciplinary treatment model. Only limited randomized data are available for patients with rectal cancer treated laparoscopically.

AIM

We report a multimodal treatment of advanced rectal cancer: preoperative oncological treatment, use of endoscopic stent (for malignant obstruction), minimal invasive treatment.

METHODS

The Authors reported a series of 45 laparoscopic rectal resections for adenocarcinoma, some of them with malignant obstruction. Long-term oncological results were reviewed.

RESULTS

The 30-day mortality was 2.2%. Of 45 adenocarcinoma, 4 cases were obstructed. Successful stent positioning was obtained in all patients and treated with radiochemiotherapy before laparoscopic resection. The 5-year global survival rate (including stage IV) was 62.2%; for stage II was 77.9% and 53.8% for stage III.

CONCLUSION

This study indicates that laparoscopy for advanced rectal cancer have good long-term results. In high and middle rectal malignant obstructions, we considered the use of stents to be useful.

Local excision after radio(chemo)therapy for rectal cancer: is it safe?

According to current opinion, local excision in rectal cancer should be limited to selected T1N0 tumours. Preoperative radio(chemo)therapy provides an opportunity for expanding the use of local excision for more advanced tumours. The key rationale of this approach is the correlation between the radiosensitivity and inherited low aggressiveness of rectal cancer and the correlation between the radiosensitivity of the primary tumour and the radiosensitivity of mesorectal nodal disease. This allows for a selection of local excision for radiosensitive tumours or conversion to abdominal surgery in radioresistant cases. Eleven reports including a total of 311 patients treated with preoperative radio(chemo)therapy and local excision have been published. In some series, the tumours were initially large and unresectable by the transanal approach. Pathological data suggest that local excision must involve all tissue invaded on pre-treatment examination with a margin, even in patients with a clinical complete response. The pooled analysis has shown a local recurrence rate of 1% (1/83) for patients achieving a pathological complete response, 8% (3/40) for ypT1, 11% (4/37) for ypT2 and 3/9 for ypT3. In conclusion, the results of preoperative radio(chemo)therapy and local excision are encouraging and warrant a population-based, multicentre controlled study.

Pelvic exenteration affords safe and durable treatment for locally advanced rectal carcinoma

BACKGROUND

Treatment of locally advanced rectal carcinoma (LARC) often involves exenterative surgery, which can be associated with high perioperative morbidity and mortality. To assist in patient selection for radical surgery, we sought to determine clinicopathologic factors influencing recurrence and disease-free survival (DFS) of LARC.

METHODS

Consecutive patients with LARC undergoing exenterative surgery were retrospectively identified in our institutional database. Factors evaluated included age, sex, primary versus recurrent tumors, neoadjuvant or adjuvant chemoradiotherapy, resection margin status, recurrence, time to recurrence, and survival. The primary outcome was DFS. Secondary outcomes were overall survival and perioperative morbidity.

RESULTS

A total of 72 patients were identified; median age was 52 years, and median follow-up time was 30 months. The overall complication rate was 43%; rates were similar among the patients with primary (47%) or recurrent (37%) LARC. Primary or recurrent tumor status was the only factor significantly predictive of outcome after exenteration. Local recurrence rates were lower in the primary group (primary 22%, recurrent 52%, P = .05). A significant difference in 5-year DFS was found between primary and recurrent tumor (52% vs. 13%; P < .01). The median time to recurrence was longer in the patients with primary LARC (17 months vs. 8 months; P < .01).

CONCLUSIONS

The complication rates for pelvic exenteration remain high, but the morbidity can typically be managed without a clinically important increase in hospitalization. In primary LARC, an aggressive surgical approach provides most patients 5-year DFS. Select patients with recurrent LARC will also benefit from pelvic exenteration.

An audit of outcomes in colorectal cancer in China

AIM

This study was designed to analyses the correlation between the extent of lymph node excision and the prognosis of colorectal cancer and to discuss the clinical significance of excision of lymph nodes adjacent to mesenteric artery pedicle.

METHODS

A total of 1409 patients with colorectal cancer who had the primary radical operation in our hospital during 1985 to 2000 was analyzed in this study. They were divided into two groups according to whether undergone an excision of lymph nodes adjacent to mesenteric artery pedicle. There were 857 patients in the excision group and 552 patients in the non-excision group. Comparison of prognoses was based on the follow-up results.

RESULTS

The 1-year, 3-year and 5-year overall survival rates of the excision group were 90%, 81% and 77%, while those of the non-excision group were 91%, 84% and 79%, respectively. The 1-year, 3-year and 5-year tumor-free survival rates of excision group were 90%, 79% and 75%, while those of the non-excision group were 90%, 83% and 76%. Kaplan-Meier analysis did not show any difference in overall survival rate or tumor-free survival rate between these two groups (P>0.05). After follow-up of 12 to 289 months there were 42 cases of local recurrence and 79 cases of metastases in the excision group. In the non-excision group local recurrence occurred in 30 cases and 60 patients had metastases. There was no difference in the rates of local recurrence and metastasis between these two groups. Multivariate correlation analyses showed that the excision of lymph nodes adjacent to mesenteric artery pedicle was not statistically correlated to recurrence, metastasis and survival time after radical operation of colorectal cancer.

CONCLUSION

In radical operation of colorectal cancer it is not necessary to perform excision of lymph nodes adjacent to mesenteric artery pedicle which is not correlated to prognosis.

The potential of restaging in the prediction of pathologic response after preoperative chemoradiotherapy for rectal cancer

BACKGROUND

We performed this study to prospectively evaluate the postchemoradiotherapy performance of transrectal ultrasonography (TRUS), pelvic computed tomography (CT) scan and magnetic resonance imaging (MRI), and endoscopic biopsies for predicting the pathologic complete response of rectal cancer patients.

METHODS

Four weeks after completion of preoperative chemoradiotherapy, 46 consecutive patients with mid to low rectal cancer were prospectively evaluated by proctoscopy, TRUS, and pelvic CT scan and MRI. On the basis of T and N status, patients were classified as T0 or T1-4 and N-negative or N-positive. For each staging modality used, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated. Findings were compared with the pathologic tumor-node-metastasis stage.

RESULTS

On histopathologic analysis, 12 patients had pT0 and 34 had pT1-4 lesions; out of 45 assessable patients, 9 were N-positive. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in predicting T status (T0 vs. T >or=1) were 77%, 33%, 74%, 36%, and 64%, respectively, for TRUS; 100%, 0%, 74%, not assessable, and 74% for CT; and 100%, 0%, 77%, not assessable, and 77% for MRI. The corresponding figures in predicting N status (N-negative vs. N-positive) were, respectively, 37%, 67%, 21%, 81%, and 61% for TRUS; 78%, 58%, 32%, 91%, and 62% for CT; and 33%, 74%, 25%, 81%, and 65% for MRI.

CONCLUSIONS

Current rectal cancer staging modalities after chemoradiotherapy allow good prediction of node-negative cases, although none of them is able to predict the pathologic complete response on the rectal wall.

Patterns of failure and survival for nonoperative treatment of stage c0 distal rectal cancer following neoadjuvant chemoradiation therapy

Neoadjuvant chemoradiation therapy (CRT) is the preferred treatment option for distal rectal cancer. Complete pathological response after CRT has led to the proposal of nonoperative approach as an alternative treatment for highly selected patients with complete clinical response. However, patterns of failure following this strategy remains undetermined. Three hundred sixty-one patients with distal rectal cancer were managed by neoadjuvant CRT including 5-FU, leucovorin, and 5040 cGy. Tumor response assessment was performed at 8 weeks following CRT. Patients with complete clinical response were not immediately operated on and were closely followed. One hundred twenty-two patients were considered to have complete clinical response after the first tumor response assessment. Of these, only 99 patients sustained complete clinical response for at least 12 months and were considered stage c0 (27.4%) and managed nonoperatively. Mean follow-up was 59.9 months. There were 13 (13.1%) recurrences: 5 (5%) endorectal, 7 (7.1%) systemic, and 1 (1%) combined recurrence. All 5 isolated endorectal recurrences were salvaged. Mean recurrence interval was 52 months for local failure and 29.5 months for systemic failure. There were five cancer-related deaths after systemic recurrences. Overall and disease-free 5-year survivals were 93% and 85%. Even though surgery remains the standard treatment for rectal cancer, nonoperative treatment after complete clinical response following neoadjuvant CRT may be safe and associated with good survival rates in a highly selected group of patients. Survival in these patients is significantly affected by systemic failure. Exclusive local failure occurs late after CRT completion and is frequently amenable to salvage therapy.

Patterns of failure and survival for nonoperative treatment of stage c0 distal rectal cancer following neoadjuvant chemoradiation therapy

Neoadjuvant chemoradiation therapy (CRT) is the preferred treatment option for distal rectal cancer. Complete pathological response after CRT has led to the proposal of nonoperative approach as an alternative treatment for highly selected patients with complete clinical response. However, patterns of failure following this strategy remains undetermined. Three hundred sixty-one patients with distal rectal cancer were managed by neoadjuvant CRT including 5-FU, leucovorin, and 5040 cGy. Tumor response assessment was performed at 8 weeks following CRT. Patients with complete clinical response were not immediately operated on and were closely followed. One hundred twenty-two patients were considered to have complete clinical response after the first tumor response assessment. Of these, only 99 patients sustained complete clinical response for at least 12 months and were considered stage c0 (27.4%) and managed nonoperatively. Mean follow-up was 59.9 months. There were 13 (13.1%) recurrences: 5 (5%) endorectal, 7 (7.1%) systemic, and 1 (1%) combined recurrence. All 5 isolated endorectal recurrences were salvaged. Mean recurrence interval was 52 months for local failure and 29.5 months for systemic failure. There were five cancer-related deaths after systemic recurrences. Overall and disease-free 5-year survivals were 93% and 85%. Even though surgery remains the standard treatment for rectal cancer, nonoperative treatment after complete clinical response following neoadjuvant CRT may be safe and associated with good survival rates in a highly selected group of patients. Survival in these patients is significantly affected by systemic failure. Exclusive local failure occurs late after CRT completion and is frequently amenable to salvage therapy.

Assessment and management of the complete clinical response of rectal cancer to chemoradiotherapy

Preoperative chemoradiotherapy is considered by many as the preferred treatment strategy for distal rectal cancer. The observation of complete tumour regression has led to the proposition of nonoperative management of selected patients with complete clinical response (cCR) following treatment. We present results for the treatment of distal rectal cancer during 1991-2005. We have outlined the issues concerning adequate tumour assessment, the definition of complete response, and the advantages and disadvantages of conservative or surgical resection in patients with clinical and radiological evidence of cCR.

Postoperative chemotherapy may not be necessary for patients with ypN0-category after neoadjuvant chemoradiotherapy of rectal cancer

PURPOSE

After neoadjuvant radiochemotherapy and surgery, there is no general agreement about whether postoperative chemotherapy is necessary. With the help of clinical and pathohistologic data, prognostic factors were determined as a basis for the decision to spare a patient additional chemotherapy or to urgently recommend it.

RESULTS

Ninety-five patients treated with neoadjuvant 5-fluorouracil-based radiochemotherapy (November 4, 1997 and June 15, 2004) without distant metastases and an R0 (microscopically complete) resection were evaluated. Adjuvant chemotherapy (5-fluorouracil or 5-fluorouracil/folinic acid) was given to 65 of 95 patients (68.4 percent). The disease-free survival rate after 36 months was chosen as the target parameter (median follow-up, 36 months).

METHODS

The five-year survival rate for all patients was 80.3 +/- 5.6 percent; the five-year disease-free survival was 78.1 +/- 5.1 percent; the five-year local control rate was 94.2 +/- 5.1 percent. In the univariate and multivariate analysis of the disease-free survival, the pathohistologic lymph node status after radiochemotherapy (ypN) was the only significant prognostic parameter. Disease-free survival (36 months) for patients without lymph node metastases (ypN0) was excellent, independent of whether they had received postoperative chemotherapy (n = 43; 87.5 +/- 6.0 percent) or not (n = 29; 87.7 +/- 6.7 percent). Patients with ypN2 status have, despite chemotherapy, a poor disease-free survival at 30 +/- 17.6 percent after 36 months.

CONCLUSIONS

These retrospective data suggest that, for some patients, postoperative chemotherapy can be spared. For patients with ypN2 status, an intensification of the postoperative chemotherapy should be considered. Further evaluation in prospective studies is urgently recommended.

Lymph node retrieval in abdominoperineal surgical specimen is radiation time-dependent

BACKGROUND

A low yield of lymph nodes (LN) in abdominoperineal resection (APR) specimen has been associated with preoperative radiation therapy (XRT) in population-based studies, which may preclude adequate staging of anorectal carcinomas. We hypothesized that the number of LN retrieved in APR specimen was correlated with the dose and the timing of pelvic irradiation.

PATIENTS AND METHODS

We performed a retrospective study of 102 patients who underwent APR in a single institution between 1980 and 2004. Pathological reports were reviewed and the number of lymph nodes retrieved in APR specimens was correlated with: 1) Preoperative radiation; 2) Dose of pelvic irradiation; and 3) Time interval between the end of XRT and surgery.

RESULTS

There were 61 men and 41 women, with a median age of 66 (range 25-89) years. There were 12 patients operated for squamous cell carcinoma of the anal canal (SCCA) and 90 for rectal cancer. 83% and 46% of patients with anal and rectal cancer respectively underwent radical/neoadjuvant radiotherapy. The mean +/- SD number of LN in APR specimen was 9.2 +/- 5.9. The mean number of LN in APR specimen was significantly lower in patients who underwent preoperative XRT (8 +/- 5.5 vs. 10.5 +/- 6.1, Mann-Whitney U test, p = 0.02). The mean number of LN was not significantly different after XRT in patients with SCCA than in patients with rectal cancer (6.2 +/- 5.3 vs. 7.8 +/- 5.3, p = 0.33). Finally, there was an inverse correlation between the yield of LN and the time elapsed between XRT and surgery (linear regression coefficient r = -0.32, p = 0.03).

CONCLUSION

Our data indicate that: 1) radiation therapy affects the yield of LN retrieval in APR specimen; 2) this impact is time-dependent. These findings have important implications with regard to anatomic-pathological staging of anal and rectal cancers and subsequent decision-making regarding adjuvant chemotherapy.