Selection criteria for local excision with or without adjuvant radiation therapy for rectal cancer

Neoadjuvant Chemotherapy, Excision, and Observation for Early Rectal Cancer: The Phase II NEO Trial (CCTG CO.28) Primary End Point Results

PURPOSE

Organ-sparing therapy for early-stage I/IIA rectal cancer is intended to avoid functional disturbances or a permanent ostomy associated with total mesorectal excision (TME). The objective of this phase II trial was to determine the outcomes and organ-sparing rate of patients with early-stage rectal cancer treated with neoadjuvant chemotherapy followed by transanal excision surgery (TES).

METHODS

This phase II trial included patients with clinical T1-T3abN0 low- or mid-rectal adenocarcinoma eligible for endoscopic resection who were treated with 3 months of chemotherapy (modified folinic acid-fluorouracil-oxaliplatin 6 or capecitabine-oxaliplatin). Those with evidence of response proceeded to transanal endoscopic surgery 2-6 weeks later. The primary end point was protocol-specified organ preservation rate, defined as the proportion of patients with tumor downstaging to ypT0/T1N0/X and who avoided radical surgery.

RESULTS

Of 58 patients enrolled, all commenced chemotherapy and 56 proceeded to surgery. A total of 33/58 patients had tumor downstaging to ypT0/1N0/X on the surgery specimen, resulting in an intention-to-treat protocol-specified organ preservation rate of 57% (90% CI, 45 to 68). Of 23 remaining patients recommended for TME surgery on the basis of protocol requirements, 13 declined and elected to proceed directly to observation resulting in 79% (90% CI, 69 to 88) achieving organ preservation. The remaining 10/23 patients proceeded to recommended TME of whom seven had no histopathologic residual disease. The 1-year and 2-year locoregional relapse-free survival was, respectively, 98% (95% CI, 86 to 100) and 90% (95% CI, 58 to 98), and there were no distant recurrences or deaths. Minimal change in quality of life and rectal function scores was observed.

CONCLUSION

Three months of induction chemotherapy may successfully downstage a significant proportion of patients with early-stage rectal cancer, allowing well-tolerated organ-preserving surgery.

Can CCRT/RT Achieve Favorable Oncologic Outcome in Rectal Cancer Patients With High Risk Feature After Local Excision?

Purpose

The oncologic outcome of concurrent chemoradiotherapy (CCRT) after local excision in patients with high-risk early rectal cancer as compared with radical operation has not been reported. The aim of this study is to compare the oncologic outcome between radical operation and adjuvant CCRT after local excision for high-risk early rectal cancer.

Materials and Methods

From January 2005 to December 2015, 266 patients diagnosed with early rectal cancer and treated with local excision who showed high-risk characteristics were retrospectively analyzed. Propensity score matching was applied in a ratio of 1:4, comparing the CCRT/radiotherapy (RT) (n = 34) and radical operation (n = 91) groups. Univariate and multivariate analyses were performed to identify prognostic factors for survival.

Results

The median follow-up period was 112 months. The 5-year disease-free survival rate and the 5-year overall survival of the radical operation group were significantly higher than those of the CCRT/RT group after propensity score matching (96.7% vs. 70.6%, p <0.001; 100% vs. 91.2%, p = 0.005, respectively). In a multivariate analysis, salvage therapy type and preoperative carcinoembryonic antigen (CEA) were prognostic factors for 5-year disease-free survival (p <0.001 and p = 0.021, respectively). The type of salvage therapy, the preoperative CEA, and the pT were prognostic factors for 5-year overall survival (p = 0.009, p = 0.024, and p = 0.046, respectively).

Conclusions

Patients who undergo radical operations after local excision with a high-risk early rectal cancer had better survival than those treated with adjuvant CCRT/RT. Therefore, radical surgery may be recommended to high-risk early rectal cancer patients who have undergone local excision for more favorable oncologic outcomes.

Adjuvant Radiation Survival Benefits in Patients with Stage 1B Rectal Cancer: A Population-based Study from the Surveillance Epidemiology and End Result Database (1973-2010)

Introduction

Rectal cancer remains a leading cause of cancer morbidity and mortality in the United States. Currently, total mesorectal excision (TME) is the standard therapy for patients with T2N0 (stage IB) rectal cancer. Whether adjuvant radiation therapy provides a survival benefit to these patients or exposes them to unnecessary toxicity remains controversial and unproven to date. This study examined a large cohort of Stage 1B rectal cancer patients who underwent surgical resection and received adjuvant radiation in order to determine the demographic, clinical, and pathologic factors impacting prognosis and survival.

Methods

Demographic and clinical data on 4,054 Stage 1B rectal cancer patients were abstracted from the Surveillance Epidemiology and End Result (SEER) database (1973-2010). Statistical analysis was performed with SPSS v20.0 software (IBM Corp., Armonk, NY) using the chi-square test, paired t-test, multivariate analysis, and Kaplan-Meier functions.

Results

Among 4,054 patients with stage IB rectal cancer, 2,364 (58.3%) had surgery only, 1,477 (36.4%) received combination surgery and radiation (CSR), 139 (3.4%) received radiation only, and 74 (1.8%) received no therapy. Most stage IB patients in the surgery only and CSR groups were male (65.8 and 64%) and Caucasian (78.2% and 74.2%), p<0.001. Patients receiving CSR were younger than those undergoing surgery alone (63 vs. 69 years, p<0.001). More tumors in the CSR group were 2-4 cm (53.6%), followed by > 4 cm (24%), while fewer were <cm (22.4%). Histologically, most of the tumors in the CSR group were moderately differentiated (83.5%) and adenocarcinoma NOS (95.5%), followed by poorly (9.3%) and mucinous adenocarcinoma (4.5%), well-differentiated (6.8%), and undifferentiated (0.4%). Overall survival was prolonged in the CSR group compared to the surgery-only group (5.85 years vs. 5.44 years, p<0.001), although cancer-specific survival did not differ (6.33 years vs. 6.42 years, p=0.143). Multivariate analysis identified age>60 (OR 2.4), poorly differentiated (OR 1.7) or undifferentiated grade (OR 2.6), and tumor size >2 cm (OR 1.5) as independently associated with increased mortality in the CSR group (p<0.05) while female gender conferred a survival advantage (OR 0.8), p<0.01.

Conclusions

In the current cohort, CSR was utilized most often in young male Caucasian patients presenting with less advanced disease as compared to other treatment groups. The overall survival is prolonged and overall mortality is lower in patients receiving CSR; however, increased cancer-related mortality with the use of CSR implies that survival benefits may be attributable to favorable non-tumor-related factors such as age, gender, and race. CSR should not replace surgery alone as the standard of care for all Stage IB rectal cancer patients at this time. However, all T2N0 rectal cancer patients should be enrolled in randomized control trials to allow for more defined multimodality management to optimize clinical outcomes for these patients.

Assessment of remaining tumour involved lymph nodes with MRI in patients with complete luminal response after neoadjuvant treatment of rectal cancer

OBJECTIVE

To assess the accuracy of MRI to predict remaining lymph node metastases in patients with complete pathological luminal response (ypT0) after neoadjuvant therapy.

METHODS

Data from a national registry were used. 19 patients with histopathologically remaining lymph node metastases (ypT0N+) were identified. Another 19 patients without lymph node metastases (ypT0N0) were used as matched controls. Two radiologists blinded to all patient information evaluated staging and restaging MRI that was compared to histopathological findings of the resected specimen.

RESULTS

The average size of the largest lymph node on restaging MRI was significantly larger (4.5 mm) in the ypT0N+ group than in the ypT0N0 group (2.6 mm) (p = 0.04). Presence of ypN+ was correctly predicted by MRI in 7 of 19 patients. In patients without lymph node metastases (ypT0N0), these were correctly classified by MRI in 16 of 19 patients. All patients who had MR-identified lymph nodes larger than 8 mm at restaging were ypTN+. The sensitivity, specificity, positive predictive value and negative for prediction of remaining lymph node metastasis with MRI were 37, 84, 70 and 57%.

CONCLUSION

In patients with ypT0 in rectal cancer after neoadjuvant treatment, remaining regional lymph node metastases cannot safely be predicted by restaging MRI alone using presently known criteria. Presence of a lymph node over 8 mm on restaging MRI strongly indicates yPN+. Advances in knowledge: This is one of the first studies on MRI lymph node assessment after chemo-radiotherapy (CRT) in luminal complete response.

Comparison of transanal endoscopic microsurgery with or without neoadjuvant therapy and standard total mesorectal excision in the treatment of clinical T2 low rectal cancer: a meta-analysis

Some clinical trials demonstrated local resection for clinical T1 rectal cancer was safe and effective. But for clinical T2 rectal cancer, the results were controversial. Neoadjuvant therapy (NT) is proven to reduce the opportunity of advanced rectal cancer recurrence in various researches. The objective of this Meta-Analysis was to evaluate the oncological outcomes of transanal endoscopic microsurgery (TEM) with or without NT comparing with conventional total mesorectal excision (TME) for the treatment of clinical T2 rectal cancer.To search for the relevant studies, an electronic search was done from the databases of Pubmed, Embase, and the Cochrane Library in this meta-analysis. We compared the effectiveness of transanal endoscopic microsurgery with or without NT and standard total mesorectal excision in the treatment of T2 Rectal Cancer. 1RCT and 3nRCTs including 121 TEM patients (TEM + NT: 59, TEM: 62) and 174 TME patients with T2 rectal cancer were retrieved. Compared with TME, there were no significant differences in the outcomes of local recurrence, overall recurrence, overall survival between TEM + NT group. However in compassion with TME, TEM without NT was associated with an increased local recurrence, overall recurrence, and a shorter overall survival, with individual ORs being 3.04 (95% Cl: 1.17-7.90; I2 = 0%), 5.67 (95% Cl: 1.58-20.38; I2 = 0%) and 0.12 (95% Cl: 0.02-0.65; I2 = 0%), respectively. Compared with TME, TEM after NT may be a feasible and safe organ preservative approach for patients with clinical T2 low rectal cancer. But for those without NT, TEM always seem be associated with worse oncological outcomes.

The degree of extramural spread of T3 rectal cancer: an appeal to the American Joint Committee on Cancer

The T3 category of the TNM classification includes over 60% of all rectal tumours and encompasses the greatest variance in cancer-specific end-points than any other T category. The most recent edition of the cancer staging handbook of the American Joint Committee on Cancer (AJCC) dated 2010 does not divide T3 tumours into subgroups which reflect cancer-specific outcome more sensitively. The original aim of the present study was to review the literature to assess the influence of the degree of extramural extent of T3 rectal cancer on local recurrence and survival. An article written by the authors was accepted for publication but was withdrawn immediately after they became aware of the publication of the 4th edition of the TNM Supplement by the Union for International Cancer Control dated 2012, which was not accessible by the search system used. This article dealt with the subdivision of the T3 category although this was not included in the most up-to-date AJCC guidelines and was stated to be 'entirely optional'. Medline, PubMed and Cochrane Library searches were performed to identify all studies that investigated the degree of extramural spread and its relationship to survival and local recurrence. Twenty-two studies were identified of which 12 assessed the degree of histopathological extramural spread measured in millimetres. In 18 of the 22 studies the degree of extramural spread was a statistically significant prognostic factor for survival and local recurrence. Analysis of the studies indicated that the subdivision of category T3 rectal cancer into two subgroups of extramural spread ≤ 5 mm or more than 5 mm resulted in markedly different survival and local recurrence rates. The data were insufficient to allow validation of any greater subdivision. Measurement of the extent of extramural spread by MRI before any treatment agreed with the histopathological measurement in the surgical specimen to within 1 mm. The extent of extramural spread in T3 rectal cancer measured in millimetres is a powerful prognostic factor. A subdivision of T3 into T3a and T3b of less than or equal to or more than 5 mm appears to give the greatest discrimination of local recurrence and survival. Preoperative T3 subdivision by MRI has the same sensitivity as histopathological examination of the resected specimen. Given the clinical need for the pretreatment classification of the T3 category for oncological management planning, the evidence strongly indicates that the subdivision of the T3 category by MRI should be formally considered as part of the TNM staging system for rectal cancer.

Clinical implications of microsatellite instability in T1 colorectal cancer

PURPOSE

The estimation of regional lymph node metastasis (LNM) risk in T1 colorectal cancer is based on histologic examination and imaging of the primary tumor. High-frequency microsatellite instability (MSI-H) is likely to decrease the possibility of metastasis to either regional lymph nodes or distant organs in colorectal cancers. This study evaluated the clinical implications of MSI in T1 colorectal cancer with emphasis on the usefulness of MSI as a predictive factor for regional LNM.

MATERIALS AND METHODS

A total of 133 patients who underwent radical resection for T1 colorectal cancer were included. Genomic DNA was extracted from normal and tumor tissues and amplified by polymerase chain reaction (PCR). Five microsatellite markers, BAT-25, BAT-26, D2S123, D5S346, and D17S250, were used. MSI and clinicopathological parameters were evaluated as potential predictors of LNM using univariate and multivariate analyses.

RESULTS

Among 133 T1 colorectal cancer patients, MSI-H, low-frequency microsatellite instability (MSI-L), and microsatellite stable (MSS) colorectal cancers accounted for 7.5%, 6%, and 86.5%, respectively. MSI-H tumors showed a female predominance, a proximal location and more retrieved lymph nodes. Twenty-two patients (16.5%) had regional LNM. Lymphovascular invasion and depth of invasion were significantly associated with LNM. There was no LNM in 10 MSI-H patients; however, MSI status was not significantly correlated with LNM. Disease-free survival did not differ between patients with MSI-H and those with MSI-L/MSS.

CONCLUSION

MSI status could serve as a negative predictive factor in estimating LNM in T1 colorectal cancer, given that LNM was not detected in MSI-H patients. However, validation of our result in a different cohort is necessary.

Treatment of stage II-III rectal cancer patients

The role and sequencing of radiotherapy in the management of T3-4 or node-positive rectal cancer has evolved over the last few decades. Given the significant local failure rate following surgery alone, both preoperative and postoperative chemotherapy and radiotherapy have been studied to decrease local and systemic failure and improve survival in these patients. This review discusses current indications and controversies for treatment of stage II-III rectal cancer patients.

Transanal endoscopic microsurgery

There is increasing interest in organ-preserving options in the management of rectal cancer. Excision of small, early stage cancers by transanal endoscopic microsurgery (TEM) is an important part of this approach. Carefully selected cancers can be treated successfully by TEM with acceptably low risk of recurrent disease and overall cancer outcomes similar to radical surgery. The impact of recurrence can be mitigated by early detection of luminal or nodal disease for which a robust surveillance programme is essential. However, patients with high risk features on post-TEM pathology should be offered completion radical surgery which is associated with good oncological results. There may be an opportunity to expand the population of patients who can be offered rectal preservation with the use of radiotherapy in either adjuvant or neo-adjuvant context. Full thickness excision by TEM may be particularly valuable in those demonstrating a clinical complete response to radiotherapy, where diagnosis of complete pathological response can be confirmed. The use of TEM in managing more advanced rectal cancers is exciting, but must be tested within formal clinical trials before being adopted as routine practice.

Meta-analysis of histopathological features of primary colorectal cancers that predict lymph node metastases

BACKGROUND

Treatment decisions for colorectal cancer vary based on lymph node status. While some histopathological features of the primary tumor correlate with lymph node spread, the relative influences of these risk factors are not well quantified.

OBJECTIVE

This study aims to systematically review published studies relating histopathological features of primary colorectal cancer to the presence of lymph node metastases and to determine how reliable certain factors might be at predicting nodal metastasis when only the primary lesion is available for study.

DATA SOURCES

Inclusive literature search using EMBASE and Ovid MEDLINE databases plus manual reference checks of all articles correlating lymphatic spread with colorectal cancer (any T stage) from 1984 to mid-2008 was performed.

STUDY SELECTION

This search generated two levels of screening utilized on 602 citations, yielding 123 articles for full review. Data reported from 76 articles were chosen.

MAIN OUTCOME MEASURES

The relative influence of each histopathological feature on the likelihood of lymphatic metastases was determined. Fixed-effects meta-analysis was performed, and results were reported as Mantel-Haenszel odds ratios (OR).

RESULTS

Of 42 histopathological features analyzed, only 40.4% were reported in >2 articles. The positive predictive values for the top quartile of most frequently reported risk factors were 25.5-86.4%. Among the commonly reported histopathological findings, lymphatic invasion (OR, 8.62) significantly outperformed tumor depth (T2 vs. T1; OR, 2.62) and overall differentiation (OR, 2.38) in predicting nodal spread. For the rectal cancer subset, risk factors differed from the overall colorectal group in predictive ability; poor differentiation at the invasive front (OR, 6.08) and tumor budding (OR, 5.82) were the most predictive.

LIMITATIONS

This literature search is limited by the small number of studies examining only rectal cancers and the potential changes in histological and/or surgical techniques over the study period.

CONCLUSIONS

No single histopathological feature of colorectal cancer reliably predicted lymph node metastases. Several risk factors that correlate highly with nodal disease are not routine components of standard pathology reports. Until further research establishes histopathological or molecular patterns for predicting lymph node spread, caution should be exercised when basing treatment decisions solely on these factors.

Local treatment for rectal cancer

The treatment of rectal cancer includes both radical resection and local therapy. Radical resection remains the standard treatment, but is associated with increased morbidity and mortality, as well as the potential need for a temporary and occasionally, a permanent ostomy. The benefits of local treatment include a less invasive procedure with maintenance of bowel function and avoidance of a stoma. However, the efficacy of local treatment is now being challenged as the rates of recurrence after local excision alone appear to be much higher than previously thought. Although the primary goal of an oncologic resection is disease eradication, each case must be individualized to determine an optimal care plan.

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.

Rectal cancer

Surgery is the cornerstone of rectal cancer treatment. Oncological cure and overall survival continue to be the main goals, but sparing of the anal sphincter mechanism and functional results are also important. The modern management of rectal cancer is a multidisciplinary approach, and pre-operative staging is of crucial importance when planning treatment in these patients. Pre-operative staging is used to determine the indication for neoadjuvant therapy prior to surgical resection or to determine whether local excision is an option in carefully selected patients with early rectal cancer. Surgery in the form of total mesorectal excision (TME) has become the standard of care for mid and distal rectal cancers. Early rectal cancers do not require neoadjuvant therapy. For locally advanced cancers of the lower two-thirds of the rectum, the combination of surgical resection with chemoradiotherapy decreases local recurrence rates and probably improves overall survival. Whereas in the past local excision was only contemplated in patients who were unfit for radical surgery or for local palliation in cases of metastatic disease, over the last number of years there has been increasing interest in local treatment with curative intent in early rectal cancer.

Multidisciplinary treatment of resectable rectal cancer

This review identifies evidence that influences current practices in the multidisciplinary treatment and shapes future directions in the treatment of resectable rectal cancer. Recent advances in surgery, radiotherapy and systemic chemotherapy have provided measurable improvements in disease control, functional outcomes and quality of life for patients with rectal cancer. However, controversies remain regarding the optimum delivery of adjuvant therapies. Preoperative radiation either with or without concurrent chemotherapy demonstrates lower recurrence, with minimal survival benefit. Currently, the use of neoadjuvant standard fractionation chemoradiation versus short-course radiation without chemotherapy is controversial and under investigation. New combinations of chemotherapeutic agents and targeted therapies are also being evaluated. In addition, criteria for patient selection are being re-evaluated to determine the relative benefit of modern treatments, so that we may better tailor adjuvant therapy recommendations to be patient-specific. Recommendations for adjuvant treatments of rectal cancer are continuing to evolve; however, survival has been only marginally affected despite low incidence of local recurrence. Future trials should aim to address the role of adjuvant therapies utilizing new criteria, such as function, quality of life and impact on development of metastatic disease.

Brachytherapy and local excision for sphincter preservation in T1 and T2 rectal cancer

PURPOSE

To report long-term results of brachytherapy after local excision (LE) in the treatment of T1 and T2 rectal cancer at risk of recurrence due to residual subclinical disease.

METHODS AND MATERIALS

Between 1989 and 2007, 32 patients undergoing LE and brachytherapy were followed prospectively for a mean of 6.2 years. Estimates of local recurrence (LR), disease-specific survival (DSS), and overall survival (OS) were generated. Treatment-related toxicity and the effect of known prognostic factors were determined.

RESULTS

There were 8 LR (3 T1, 5 T2), of which 5 were salvaged surgically. Median time to the 8 LR was 14 months, and the 5-year rate of local control was 76%. Although there have been 9 deaths to date, only 5 were from disease. Five-year DSS and OS rates were 85% and 78%, respectively. There were 4 cases of Grade 2-3 radionecrosis and 1 case of mild stool incontinence. The sphincter was preserved in 27 of 32 patients.

CONCLUSION

Local excision and adjuvant brachytherapy for T1 and T2 rectal cancer is an appealing treatment alternative to immediate radical resection, particularly in the frail and elderly who are unable to undergo major surgery, as well as for patients wanting to avoid a permanent colostomy.

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.

Current options for the management of rectal cancer

Patients diagnosed with rectal cancer should undergo locoregional staging with transrectal endoscopic ultrasound (EUS) or surface coil array MRI of the pelvis if that technique is available. Patients thought to have more than very early stage (T1 or T2) disease should undergo abdominal imaging as well by CT or MRI, and chest imaging with either CXR or preferably CT. The care of rectal cancer patients should be coordinated amongst an experienced multidisciplinary team to maximize the chance of cure and to minimize both local recurrence and complications of therapy. For patients with very early stage disease (T1N0 or T2N0), local resection with or without chemoradiation may be adequate therapy, but these patients must be selected carefully and should be without any poor prognostic factors. For the majority of patients with T3N0 or greater rectal cancer, standard therapy consists of neoadjuvant continuous 5-FU and radiation followed by surgery and further chemotherapy (either with 5-FU, capecitabine, or FOLFOX). The use of capecitabine, irinotecan, and oxaliplatin during radiotherapy shows promise, but remains investigational pending results of phase III studies. Neoadjuvant therapy is preferred because it decreases local recurrence and appears to result in improved postoperative bowel function in comparison with postoperative therapy. Select patients with high (>10 cm from the anal verge) uT3N0 tumors may be at sufficiently low risk of local recurrence to justify omission of radiotherapy. Patients who experience pathologic complete response to radiotherapy should still receive postoperative adjuvant chemotherapy to reduce systemic recurrence risk until data demonstrate that this is not necessary. Patients with stage IV rectal cancer may still require local therapy with radiation, surgery, or both; however, care should be taken in these patients that chemotherapy is not excessively delayed as this is the one modality in this case that can result in improved survival.

Transanal local excision for preoperative concurrent chemoradiation therapy for distal rectal cancer in selected patients

PURPOSE

To evaluate the clinical course and outcomes of patients with T2 or T3 rectal cancer treated by transanal local excision after preoperative chemoradiation therapy (CRT).

METHODS

Between June 2000 and August 2004, seven patients underwent local excision of T2 or T3 rectal cancer after preoperative CRT. Preoperative clinical staging was on the basis of the findings of endorectal ultrasound. Computed tomography (CT) and digital rectal examination consisted of radiation therapy with 4 500 cGy/25 fractions, given over 5 weeks with 5-FU-based chemosensitization. Local excision was performed 4-7 weeks later.

RESULTS

The mean age of the patients was 54.9 (35-70) years and the median follow-up period was 23 (5-57) months. The lesions were located 2-6 cm above the anal verge (median 3.0 cm). Pretreatment T staging was estimated as T3 in one patient, and T2 in six patients. Post-treatment T staging was estimated as complete remission (CR) in two patients, T1 in three patients, and T2 in two patients. Pathologic evaluation revealed tumor downstaging in six patients, including three (42.9%) with CR. No tumor cells were seen in the resection margin and there was no sign of recurrence in any of the patients.

CONCLUSION

These findings support local excision after preoperative CRT as an effective alternative to radical resection in carefully selected patients with T2 and T3 distal rectal cancer.

Mucinous rectal adenocarcinoma can be associated to tumor downstaging after preoperative chemoradiotherapy

PURPOSE

The aim of this study was to evaluate downstaging as primary end point, and progression-free survival and overall survival as secondary end points, in rectal adenocarcinoma patients treated with preoperative chemoradiation.

METHODS

One hundred and thirty-six extraperitoneal adenocarcinoma patients (33 low rectum T2, 74 T3, 29 T4 [without sacral invasion], 25 with mucinous subtype) were treated with posterior pelvis preoperative radiotherapy (5040 cGy total dose, 180 cGy/fr, 5 fr/w, 10-15 MV linac X-rays) and concomitant 5-fluorouracil-based chemotherapy. After 6 to 8 weeks patients underwent surgery and prechemoradiation clinical stage was compared with pathologic stage to evaluate downstaging in each patient. Seventy-four patients received adjuvant chemotherapy. Median follow-up was 39 months (4-84).

RESULTS

Forty-four patients had macroscopic complete response, 52 patients had partial response, 37 patients showed no change and 3 patients had progression. At multivariate analysis only histotype showed correlation with downstaging (hazard ratio = 0.350 and 0.138 - 0.885 95 percent confidence interval) because of the evidence for poor downstaging in mucinous subtype. There were no significant differences in overall survival and progression-free survival between adenocarcinoma and mucinous subtype.

CONCLUSIONS

The main finding is that mucinous histology is associated with poor downstaging after preoperative chemoradiation but this poor response was not associated with worse outcome in this small study. The good outcome for mucinous histology is at odds with other reports in the literature and requires further study.

Local therapy for rectal cancer: still controversial?

PURPOSE

Many considerations, such as morbidity, sexual and urinary dysfunction, or risk of definitive stoma have led to the increased popularity of local therapy in the therapeutic strategy for rectal cancer. However, its role in curative intent is still controversial with oncologic long-term results lower than those obtained by radical surgery.

METHODS

MEDLINE, EMBASE, LILACS, Abstract books, and reference lists from reviews were searched with English language publications to review the current status of evidence for local therapy in rectal cancer, looking especially at the oncologic results and patient selection. We have focused on the new strategies combining neoadjuvant and adjuvant treatment to explain their place in the management of rectal cancer.

RESULTS AND CONCLUSIONS

The key to potentially curative local treatment for rectal cancer is patient selection by identifying the best candidates with preoperative tumor staging and clinical and pathologic assessment of favorable features. Low-risk T1 is suitable for local excision alone. Limited data suggest that adjuvant chemoradiotherapy may be helpful in patients with unfavorable T1 and T2 lesions, achieving a local recurrence rate<20 percent. However, the efficacy of salvage surgery after local excision is uncertain.

Organ preservation for rectal cancer

Organ preservation with maintenance of function in the treatment of rectal cancer is highly valued by patients. Although most patients with resectable rectal cancer can undergo a sphincter-sparing radical procedure, there are patient, tumor, surgeon, and treatment factors that influence the ability to restore intestinal continuity after radical resection. Although population-based data suggest that the rate of sphincter preservation is lower than could be obtained at expert centers, there are patients in whom low anterior resection with colo-anal anastomosis is not technically feasible and/or oncologically sound. Additionally, resection with ultralow anastomosis results in functional compromise in many patients. Local treatment of rectal cancer aims to decrease the morbidity and the functional sequelae associated with radical resection; however, local excision is associated with a higher rate of local recurrence than is radical resection. Strict selection criteria are essential when considering local excision, and patients should be informed of the risk of local recurrence. The use of adjuvant therapy with local excision, particularly in patients with T2 lesions, has promise but should be considered only as part of a clinical trial.

Colorectal cancer

Cancers of the colon and rectum will affect 1 in 17 North Americans during their lifetime. The progress witnessed in the treatment of these cancers in recent years has been remarkable. Improvements have been realized in surgical technique, radiation therapy, and systemic therapies, particularly with the addition of oxaliplatin and irinotecan to the previously limited armamentarium of fluorouracil alone. Targeted therapies directed at the vascular endothelial growth factor pathway and the epidermal growth factor pathway are now key players in the treatment of colorectal cancer. With current-day therapies, more than 75% of patients with localized disease are recurrence free at 3 years, and up to 50% of patients with advanced unresectable disease are alive at 2 years. This review focuses on the evidence supporting the current role of chemotherapy and radiation therapy in the adjuvant management of colorectal cancers and the strategy of combining chemotherapy and biological therapy in the treatment of metastatic disease.

Decision for salvage treatment after transanal endoscopic microsurgery

BACKGROUND

Transanal endoscopic microsurgery (TEM) has emerged as an alternative to classic radical operation for early rectal cancer. Early rectal cancer can be treated by adequate local excision such as TEM. If there are adverse risk factors, especially poor cellular differentiation, close resection margin, or positive lymphovascular invasion or incomplete excision, a radical resection is indicated. This study aimed to clarify the factors related to recurrence for patients required to undergo a salvage operation after TEM.

METHODS

This retrospective study analyzed 167 patients who underwent TEM for rectal cancer between 1994 and 2004. Of these patients, 36 with poor differentiation, mucinous carcinoma, proper muscle invasion, lymphovascular invasion, and positive resection margin were included in the analysis.

RESULTS

Of the 36 patients, 12 underwent a salvage operation, and the remaining 24 did not because of poor physical condition or refusal of radical surgery. There were a total of 6 (16.7%) recurrences. One (8.3%) of the 12 patients who underwent salvage surgery had systemic recurrence. Five (20.8%) of the 24 patients who did not receive surgery had recurrence (3 local recurrences, 2 distant recurrences). Analysis of the subgroups showed that 2 (28.6%) of 7 patients with lymphovascular invasion had recurrence, and that 1 patient (100%) had a T3 lesion. Three (17.6%) of 17 patients had T2 lesions.

CONCLUSIONS

For high-risk patients, TEM followed by radical surgery is the most beneficial in preventing local recurrence. Radical salvage surgery is strongly recommended if pathologic results after TEM show T3 lesion or lymphovascular invasion.

Colorectal cancer

Cancers of the colon and rectum will affect 1 in 17 North Americans during their lifetime. The progress witnessed in the treatment of these cancers in recent years has been remarkable. Improvements have been realized in surgical technique, radiation therapy, and systemic therapies, particularly with the addition of oxaliplatin and irinotecan to the previously limited armamentarium of fluorouracil alone. Targeted therapies directed at the vascular endothelial growth factor pathway and the epidermal growth factor pathway are now key players in the treatment of colorectal cancer. With current-day therapies, more than 75% of patients with localized disease are recurrence free at 3 years, and up to 50% of patients with advanced unresectable disease are alive at 2 years. This review focuses on the evidence supporting the current role of chemotherapy and radiation therapy in the adjuvant management of colorectal cancers and the strategy of combining chemotherapy and biological therapy in the treatment of metastatic disease.

Predictors of recurrence in patients with T2 and early T3, N0 adenocarcinoma of the rectum treated by surgery alone

PURPOSE

Treatment of rectal cancer with neoadjuvant radiotherapy has been shown to reduce local recurrence and improve overall survival. The role of chemoradiotherapy in patients with T2, N0 and early T3, N0 rectal cancer, treated by radical surgery with total mesorectal excision, remains controversial. The aim of this study was to identify predictors of recurrence in this group of patients to enhance treatment selection.

PATIENTS AND METHODS

One hundred patients with primary T2-3, N0 adenocarcinoma of the rectum, uniformly treated by surgery alone, were studied. The pathology slides available for 97 patients were rereviewed. Three patients with incomplete data sets were excluded. Clinical and survival data were obtained from a prospective computerized database and updated from hospital and office charts. The study end points were disease-free survival, disease-specific survival (DSS), time to pelvic recurrence (PR), and distant recurrence.

RESULTS

Complete follow-up was available for all study patients. Median follow-up was 79.5 months (range, 57.7 to 105.9 months). During this time period 30 patients (31.9%) died as a result of disease and 64 patients (68.1%) remained alive and disease free. Five-year DSS was 73%. The cumulative risk for PR was 8% at 5 years and 10% at 8 years. Lymphovascular invasion, preoperative serum carcinoembryonic antigen (CEA > 5 ng/mL) level, and age older than 70 years were all associated with adverse outcome. CONCLUSION Patients with T2-3, N0 rectal cancers and either lymphovascular invasion or elevated CEA levels have reduced survival and a higher incidence of PR, and should be considered for future randomized trials.

Is T classification still correlated with lymph node status after preoperative chemoradiotherapy for rectal cancer?

BACKGROUND

It is well known that the risk of lymph node involvement increases according to pathologic T classification in rectal cancers, but to the authors' knowledge, the correlation between risk of lymph node involvement and ypT classification in rectal cancers treated with preoperative chemoradiotherapy (CRT) remains unclear. The current study investigated the correlation between tumor involvement in regional lymph nodes and rectal mural tumor status in patients who underwent preoperative CRT for rectal cancer.

METHODS

Between October 2001 and February 2005, 282 patients underwent preoperative CRT followed by proctectomy for locally advanced rectal adenocarcinoma. Correlations between lymph node status and ypT classification, Dworak regression grade, and magnetic resonance (MR) volumetry findings were explored.

RESULTS

Lymph nodes harboring tumors were found in 87 of 282 (30.9%) patients. The rate of lymph node involvement was found to be correlated with ypT-classification (P < .001); positive lymph nodes were detected in 1 of 45 (2.2%) ypT0 patients, 1 of 13 (7.7%) ypT1 patients, 13 of 77 (16.9%) ypT2 patients, 69 of 140 (49.3%) ypT3 patients, and 3 of 7 (42.9%) ypT4 patients. The rate of lymph node involvement decreased as Dworak regression grade increased (P < .001); tumor-harboring lymph nodes were found in 62.3% of Grade 1 patients, 31.4% of Grade 2 patients, 16.1% of Grade 3 patients, and 2.2% of Grade 4 patients. There were no differences noted with regard to MR volumetry findings, including mean volume of pre- or post-CRT tumor and the tumor volume reduction rate between lymph node-negative and lymph node-positive patients.

CONCLUSIONS

Pathologic T classification is still the most reliable predictor of lymph node metastasis in rectal cancer patients who have undergone preoperative CRT. The risk of lymph node metastasis was found to be 3.4% in rectal cancer that had regressed to ypT0 or ypT1.

Can Rectal Cancers With Pathologic T0 After Neoadjuvant Chemoradiation (ypT0) Be Treated by Transanal Excision Alone?

BACKGROUND

Patients with rectal cancer who have complete rectal wall tumor regression after neoadjuvant chemoradiation probably have eradication of tumor cells in the mesorectum as well, thus raising the possibility of transanal excision.

METHODS

All pathology reports of all patients with locally advanced low and mid rectal cancer who underwent preoperative chemoradiation followed by radical resection from May 2000 to June 2004 were reviewed to evaluate the correlation between complete tumor response (ypT0) and nodal response.

RESULTS

One hundred one consecutive patients had neoadjuvant chemoradiation followed by definitive operation. Four were excluded, leaving 64 men and 33 women (median age, 62 years). Fifty-three patients (55%) had mid rectal cancer, and 44 (45%) had low rectal cancer. Fifty-eight patients (60%) underwent low anterior resection, and 36 (37%) underwent abdominoperineal resection. In 17 patients (18%), no residual tumor cells were present within the rectal wall. One patient (6%) with ypT0 disease had positive lymph nodes.

CONCLUSIONS

No residual tumor in the rectal wall correlates with the absence of viable cancer cells in the mesorectal tissue (94%). Approximately 10% of T1 tumors have involved lymph nodes, and local excision is an accepted option. Transanal excision could probably be considered in a highly selected group of patients with a mural pathologic complete response to neoadjuvant therapy. This approach should be prospectively investigated, and strict selection guidelines should be used.

Surgical Treatment of Rectal Cancer: Local Resection

Local treatment of rectal cancer aims to decrease the morbidity and the functional sequela associated with radical surgery without compromising local tumor control and long-term survival. Local excision is associated with a higher rate of local recurrence compared with radical surgery, and salvage radical surgery cannot guarantee equivalent long-term survival compared with radical surgery as the primary form of therapy. Therefore, strict criteria for patient selection are critical for local excision to be successful. Selecting the optimal therapy for an individual patient with rectal cancer is crucial and requires consideration of both tumor and patient characteristics. Endorectal ultrasonography is essential for the accurate assessment of rectal wall invasion and nodal metastasis. Only patients with well- or moderately differentiated T1 tumors without blood vessel or lymphatic vessel invasion are candidates for curative local excision as the only form of treatment. Tumors penetrating the muscularis propria should not be treated by local excision alone. These patients can be asked to participate in a trial of chemoradiation followed by local excision. Otherwise, they should undergo radical surgery. The tumor should be removed by full-thickness local excision with an adequate normal margin for pathologic evaluation. Final decisions regarding the treatment strategy should be based on the pathology of the surgical specimen. Intense, close follow-up is critical for early diagnosis of local recurrences as many of them may be surgically salvaged by radical resection. Local treatment can also be used for palliation of patients with histological unfavorable or advanced tumors, and those who are medically unfit for radical surgery.

Can pathological complete response in the primary tumour following pre-operative pelvic chemoradiotherapy for T3-T4 rectal cancer predict for sterilisation of pelvic lymph nodes, a low risk of local recurrence and the appropriateness of local excision?

INTRODUCTION

Local excision is considered inappropriate treatment for T3-T4 rectal adenocarcinomas, as it cannot provide prognostic information regarding lymph node involvement and has a high risk of pelvic recurrence. Preoperative chemoradiation (CRT) studies in rectal cancer suggest that a pathological complete response (pCR) in the primary tumour provides an excellent long-term outcome. If downstaging to stage pT0 predicts a tumour response within the perirectal and pelvic lymph nodes, this may allow local excision to be performed without increased risk of pelvic recurrence. This retrospective study aimed to determine the incidence of involved lymph nodes following pCR (ypT0) after preoperative CRT and total mesorectal excision.

METHOD

The outcome and treatment details of 211 patients undergoing preoperative CRT for clinically staged T3-T4 unresectable rectal adenocarcinomas between 1993 and 2003 at Mount Vernon Hospital were reviewed.

RESULTS

Data were recorded from the 143 patients who completed treatment with a median follow-up of 25 months. Twenty-three patients (18%) were found to have had a pCR. Four out of 23 patients (17%) had involved lymph nodes. No pelvic recurrences developed after a ypCR. Overall survival was similar for patients with ypT0 or residual tumour.

CONCLUSION

Pathological complete response in the primary tumour failed to predict a response in the perirectal lymph nodes (p=0.08). The degree of response predicted a lymph node response (p=0.02). The detection of ypCR identified patients with a low rate of pelvic recurrence. This may in the future allow selection of patients for whom local excision can be performed without a higher risk of local relapse.

Transanal excision vs. major surgery for T1 rectal cancer

PURPOSE

The purpose of this national study was to examine the long-term results of transanal excision compared with major surgery of T1 rectal cancer.

METHODS

This prospective study from the Norwegian Rectal Cancer Project included all 291 patients with a T1M0 tumor within 15 cm from the anal verge treated by anterior resection, abdominoperineal resection, Hartmann's procedure, or transanal excision in the period from November 1993 to December 1999.

RESULTS

Two hundred fifty-six patients were treated by major surgery and 35 patients by transanal excision. None of the patients had neoadjuvant therapy. Macroscopic tumor remnants (R2) occurred in 17 percent (6/35) of the transanal excisions, while major surgery obtained 100 percent R0 resections. Eleven percent of the patients treated with major surgery had glandular involvement. There were no significant differences according to tumor localization, size, or differentiation between Stage I and Stage III tumors. Patients treated with transanal excision were older than patients having major surgery (mean age, 77 vs. 68 years, P < 0.001). After curative resection (R0, R1, Rx) the five-year rate of local recurrence was 12 percent (95 percent confidence interval, 0-24) in the transanal excision group compared with 6 percent (95 percent confidence interval, 2-10) after major surgery (P = 0.010). The overall five-year survival was 70 percent (95 percent confidence interval, 52-88) in the transanal excision group compared with 80 percent (95 percent confidence interval, 74-85) in the major surgery group (P = 0.04) and the five-year disease-free survival was 64 percent (95 percent confidence interval, 46-82) in the transanal excision group compared with 77 percent (95 percent confidence interval, 71-83) in the major surgery group (P = 0.01).

CONCLUSIONS

The main problem of transanal excision for early rectal cancer in the present study was the inability to remove all the malignancy. Patients treated with transanal excision had significantly higher rates of local recurrence compared with patients who underwent major surgery. Patients who had transanal excision had inferior survival, but they were older than those who had major surgery.

Is local excision of T2/T3 rectal cancers adequate?

In selected patients, local excision of rectal cancer may be an alternative to radical surgery such as abdominoperineal excision of the rectum or anterior resection. Local excision carries lower mortality and morbidity, without the functional disturbance or alteration in body image that can be associated with radical surgery. There are several techniques of local therapy for rectal cancer, with most experience being available in transanal excision. Transanal endoscopic microsurgery is also used but experience with this newer technique is limited. Patient selection is the most important factor in successful local excision; however, specific criteria for selecting patients have not been universally accepted. Review of the published literature is difficult because of the variation in adjuvant therapy regimes and follow-up strategies, as well as results reported in terms of local recurrence and survival rates. There is increasing evidence to suggest that local excision should be restricted to patients with T1-stage rectal cancer without high-risk factors. The place for local excision in patients with T2 or high-risk T1 tumours requires prospective, randomised multicentre trials comparing radical surgery with local excision, with or without adjuvant therapy. Local excision for T3 tumours should be restricted to the palliative setting or patients unfit for radical surgery.

Postoperative morbidity and recurrence after local excision of rectal adenomas and rectal cancer by transanal endoscopic microsurgery

OBJECTIVE

Tumours in the middle and upper part of the rectum are not easy accessible to local excision. Transanal endoscopic microsurgery (TEM) has been recommended for excision of sessile adenomas in the middle and upper part of the rectum, and for small cancers in patients not fit for major surgery. The purpose of this study was to evaluate postoperative morbidity and local recurrence after TEM.

MATERIAL AND METHODS

Seventy-nine patients were treated by TEM in the period 1994-2001. The median age was 74 years. The indications for TEM were rectal adenoma in 72 patients and rectal cancer in 7 patients. The tumours were located within 18 cm from the dentate line, median 10 cm. There were performed 69 transmural and 10 mucosal excisions. Mean follow up was 24 months (range 1-95 months). Twenty (25%) patients died during the follow up period, two because of metastases and 18 of other causes.

RESULTS

Seven patients had complications. Two (2.5%) patients had peroperative perforation in the intra-abdominal part of the rectum treated by laparotomy. Five (6%) patients had postoperative cardiopulmonal or surgical complications. Eight patients with benign pre-operative histopathological examination had cancer. The local recurrence rate (13%) was similar for adenomas and for carcinomas.

CONCLUSION

TEM is a safe technique well tolerated also by high-risk patients, and should be the preferred method in patients with benign tumours in the middle and upper part of the rectum, and in selected cases of early rectal cancer. Benign pre-operative histology does not preclude malignancy and some patients may need further treatment for unexpected malignancy.

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

BACKGROUND

We investigated the relationship between pathologic T-stage and mesorectal metastases after preoperative chemoradiotherapy (CRT) for clinical stage II to III rectal carcinoma.

METHODS

The records of consecutive patients with clinical stage II to III carcinoma of the mid or low rectum who underwent surgery after CRT were reviewed. Indications for preoperative CRT were cancer up to 11 cm from the anal verge, Eastern Cooperative Oncology Group performance status of 0 to 2, age 18 to 75 years, and clinical tumor-node-metastasis stage II or III.

RESULTS

The study group consisted of 235 patients (148 men and 87 women; median age, 61 years). The pretreatment tumor-node-metastasis stage was as follows: I, n = 1; II, n = 96; and III, n = 138. Radiotherapy was delivered at a median dose of 50.4 Gy. A pathologic complete response on the rectal wall was found in 24% of patients, and nodal metastases were found in 20% of patients. According to the pT stage, the rate of node positivity was 2% for pT0, 15% for pT1, 17% for pT2, 38% for pT3, and 33% for pT4 cases. At multivariate analysis, the best model for predicting pathologic node involvement included young age, positive pretreatment N status, and pT status. On considering pT stage alone, the odds ratio was in the region of 10 for pT1/2 and >20 for pT3/4 patients.

CONCLUSIONS

In patients with pT0 after preoperative CRT for clinical stage II to III mid or low rectal cancer, the risk of nodal metastases is very low. More conservative surgery (local excision) may be considered in these cases.

Long-Term Results of Local Excision with and Without Chemoradiation for Adenocarcinoma of the Rectum

The role of local excision for rectal carcinoma remains controversial. We reviewed 285 patients undergoing curative resection for rectal cancer between 1984 and 2001. Surgical procedures were local excision (LE; n = 49), abdominoperineal resection (APR; n = 124), and low anterior resection (LAR; n = 112). Median follow-up for all patients was 6.2 years. For patients undergoing local excision, postoperative tumor stages were Tis (22%), T1 (41%), T2 (18%), and T3 (18%). Twelve patients received postoperative radiation >/= 45 Gy, and 4 patients received adjuvant chemotherapy. Of the 49 patients who underwent LE, the 5- and 10-year overall survival rates were 76% and 42%, respectively. The 5- and 10-year disease-free survival rates were 69% and 58%, respectively. The incidence of local recurrence was 16% and the incidence of distant recurrence was 6%. For the 11 patients who experienced disease recurrence, the median time to recurrence was 13 months (range, 1-59 months). Of the 8 patients who developed local recurrence, 4 refused salvage treatment, 2 underwent salvage APR, and 2 underwent repeat excision. Of the 4 who underwent salvage surgery, one is alive with no evidence of disease, one developed distant disease, and 2 died with unknown disease status. Adjuvant therapy did not affect survival or recurrence rates in patients undergoing LE compared with other surgeries. The rate of local failure (16%) is comparable to that observed in the Cancer and Leukemia Group B (CALGB) 8984 prospective study and suggests that highly selected patients undergoing local excision can expect good local control of rectal cancer.

[PET/CT for colorectal and hepatic tumors]

This contribution presents clinical and technical aspects of combining positron emission tomography (PET) and computed tomography (CT) for patients with colorectal tumors and characterization of unclear liver foci. In which manner and for which patients combined PET/CT is superior to PET or CT alone is also discussed. PET/CT can fulfil most prerequisites for imaging in pre- and postoperative management of patients with colorectal tumors and best meets the desire for optimal imaging procedures. Some of the disadvantages encountered in frequently employed CT can be overcome by the combination of PET and CT while increasing both sensitivity in detecting lesions and specificity in their characterization. Questions regarding treatment response offer an opportunity for devising novel study concepts and initiating research on new PET tracers. Although few publications are available, we are of the opinion that the combination of functional and anatomical imaging provided by PET/CT can improve both preoperative management and aftercare. To this end, however, optimum cooperation between practitioners of nuclear medicine and radiology is imperative.

Outcome of local excision of rectal carcinoma

PURPOSE

This study was designed to determine the results of patients with rectal adenocarcinoma treated with local excision.

METHODS

A retrospective, chart review was conducted for all patients treated with local excision for rectal adenocarcinoma from 1984 to 1998.

RESULTS

Sixty-four patients were retained for analysis. The median follow-up was 37 (range, 9-125) months. There were 15 local failures with a median time to local failure of 12 months. Seven patients were salvaged with further operation (4 by repeat local excision, 4 by abdominoperineal resection, and 1 by low anterior resection). The incidence of local recurrence increased with advancing stage of the carcinoma (T1, 13 percent; T2, 24 percent; T3, 71 percent), histologic grade of differentiation, (well, 12 percent; moderately, 24 percent; poorly, 44 percent), and margin status (negative, 16 percent; close (within 2 mm), 33 percent; positive, 50 percent). Sixteen percent of carcinomas < or = 3 cm failed compared with 47 percent for carcinomas > 3 cm. Nine percent (1/11) of T2 patients treated with adjuvant radiation therapy recurred locally compared with 36 percent (5/14) without radiation therapy. Three of four T3 patients who received radiation therapy failed locally compared with two of three who did not. Using the Kaplan-Meier method, the overall survival at five years was 71 percent, and disease-free survival was 83 percent. Actuarial local failure was 27 percent and freedom from distant metastasis was 86 percent. The sphincter preservation rate was 90 percent at five years.

CONCLUSIONS

Local excision alone is an acceptable option for well-differentiated, T1 carcinomas, < or = 3 cm. Adjuvant radiation is recommended for T2 lesions. The high local recurrence rate in patients after local excision of T3 lesions with or without adjuvant radiotherapy would mandate a radical resection.

Full-thickness intraperitoneal excision by transanal endoscopic microsurgery does not increase short-term complications

PURPOSE

Transanal endoscopic microsurgery (TEM) is a minimally invasive technique for full-thickness excision of benign and malignant rectal neoplasms located 4 to 24 cm above the anal verge. Entrance into the peritoneal cavity during TEM has been regarded as a complication that mandates conversion to open laparotomy for adequate repair of the defect. This study compares the rate of complications arising from TEM with and without intraperitoneal entry.

METHODS

Patients undergoing peritoneal entry were compared to those who did not.

RESULTS

No perioperative deaths occurred. There was no significant difference in the incidence of postoperative complications. No major complications occurred with peritoneal entry, and all peritoneal entries were closed transanally via endoscope.

CONCLUSIONS

Entry into the peritoneum during TEM is not associated with an increased incidence of complication. Entry into the peritoneum during TEM excision does not mandate conversion to open laparotomy but may be safely repaired endoscopically. Lesions likely to be above the peritoneal reflection and within reach of the endoscope (4 to 24 cm) should be considered for TEM excision.

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

BACKGROUND

In order to evaluate the impact of preoperative radiation and chemotherapy (combined modality therapy, or CMT) on primary rectal cancer and mesorectal lymph nodes (MLNs), middle and lower third rectal cancers were resected with total mesorectal excision (TME) and assessed for frequency of MLN retrieval and residual MLN involvement.

METHODS

Between 1990 and 2001, 187 consecutive patients underwent abdominoperineal resection (APR) or low anterior resection (LAR) for locally advanced (endorectal ultrasound [ERUS] stage, T3-4) mid and distal rectal cancer following preoperative CMT. Sphincter preservation was possible in 150 patients (80%). The mean number of retrieved MLNs was 10.6. Pre-CMT ERUS stage was compared with final pathologic stage.

RESULTS

Comparison of pre-CMT ERUS stage with pathologic stage revealed a decrease in T stage in 93 patients (49%), as well as a decrease in the percentage of individuals with positive MLNs, from 54% to 27% (P <.0001). The overall incidence of positive MLN involvement was 27%, and incidence paralleled pathologic T stage (pT): pT0 = 7%, pT1 = 8%, pT2 = 22%, pT3 = 37%, and pT4 = 67%.

CONCLUSIONS

Following preoperative CMT, the incidence of residual MLN involvement remains significant and parallels increasing pT stage. Therefore, the standard of care for locally advanced distal rectal cancer should continue to include formal rectal resection (TME).

Transanal endoscopic microsurgery and radical surgery for T1 and T2 rectal cancer

BACKGROUND

Transanal endoscopic microsurgery (TEM) has gained increasing acceptance as a local treatment of early rectal cancer. The purpose of this study was to compare the results of TEM and radical surgery in patients with T1 and T2 rectal cancer.

METHODS

From October 1994 to December 2000, 74 patients with T1 and T2 rectal adenocarcinoma treated with TEM were compared with 100 patients with T1N0M0 and T2N0M0 rectal adenocarcinoma treated with radical surgery. Retrospective analysis was performed regarding to recurrence and survival rate. Neither group received adjuvant chemoradiation. There was no significant difference in age, gender, tumor location, or follow-up period between the two groups. The only difference was in tumor size.

RESULTS

Of the 74 patients in TEM group, 52 were T1 (70.3%) and 22 were T2 (29.7%). Of the 100 patients in radical surgery group, 17 were T1 (17%) and 83 patients were T2 (83%). The 5-year local recurrence rates were 4.1% for T1, 19.5% for T2 after TEM, 0% for T1, and 9.4% for T2 after radical surgery. There was no statistical difference between the TEM and radical surgery groups for T1 rectal cancer ( p = 0.95), but for T2 rectal cancer, the 5-year local recurrence rate was higher after TEM than after radical surgery ( p = 0.04). There were no significant statistical difference between the two groups in terms of the 5-year disease-free survival rate and the survival rate.

CONCLUSIONS

For T1 rectal cancer, there was no difference in recurrence or 5-year survival rate between the TEM and the radical surgery groups. For T2 rectal cancer, there was no statistical difference in the 5-year survival rate between the two groups, but TEM carried higher risk of local recurrence. Therefore, careful selection of the patients is required for TEM, and when proper muscle invasion is proven, the TEM procedure should be supplemented by further treatment, or radical surgery should be performed.

Local therapy for rectal cancer

Local procedures for carefully selected distal rectal cancer offer significant advantages such as sphincter preservation and avoidance of radical surgery. However, since preoperative selection criteria including current imaging modalities are unable to definitively stage regional lymph node status, local therapies for rectal cancer have the inherent potential disadvantage of undertreating a fraction of patients due to unresected mesorectal/regional lymph node disease. Current available data suggests that the local approach may be appropriate only for carefully selected T1 tumors with favorable pathologic features. Inferior local control and survival reported for T2 tumors and T1 tumors with unfavorable features, despite the addition of chemoradiation, outweigh the advantages of the local approach. Patients with unfavorable tumors who are unable to tolerate radical resection or who refuse surgery may be treated with local excision with or without adjuvant chemoradiation. Other modalities, such as electrocoagulation and endocavitary radiation, may also be valuable in this setting, as well as preoperative chemoradiation followed by local excision. Regardless of the approach used, all patients undergoing local therapy of a rectal cancer require careful long-term follow-up, because these patients remain at significant risk for local recurrence and distant failure.

Surgical treatment of rectal cancer

Rectal cancer should no longer be thought of as only a surgically treated disease. Centers that treat large numbers of rectal cancer patients should provide state of the art radiotherapy and chemotherapy as well as offer anatomic tumor-specific operations for advanced-stage cancers and local treatment options for favorable, early lesions.