Recent advances in the treatment and outcome of locally advanced rectal cancer

The Predictive Value of Clinical Evaluation of Response to Neoadjuvant Chemoradiation Therapy for Rectal Cancer

Introduction

Multimodality therapy has become the standard treatment for patients with locally advanced (T3 and T4) rectal carcinoma. Accurate preoperative staging of the patients with rectal cancer has increased in importance because the selection of patients with transmural rectal cancer (T3 or T4) or node-positive disease leads to a previous nonsurgical neoadjuvant treatment. The purpose of this study was to evaluate the predictive value of the clinical response to neoadjuvant therapy on the basis of pathological results obtained on rectal cancer patients treated by chemoradiotherapy and surgery.

Methods

From 1994 to 2003, 58 patients with a primary diagnosis of rectal cancer were studied at our department and enrolled in a neoadjuvant protocol of chemoradiotherapy followed by surgery. All patients were treated by 30 days of chemoradiotherapy. At the end of the chemoradiotherapy, each patient underwent clinical examination, including digital rectal examination, proctoscopy and abdominal-pelvic computerized tomography to define the clinical response to the chemoradiotherapy. Surgical resection was performed in all patients three weeks after the end of chemoradiotherapy, and histological analysis was performed on all resected specimens.

Results

The clinical complete response rate corresponded to the pathological complete response rate, whereas the clinical evaluation overestimated partial response and stable disease. The pathologic examination revealed that 3.5% of clinical partial responses and 3.4% of clinical stable disease were really pathological progressive disease. Clinical partial response and clinical stable disease positive predictive values were 92.8% and 90.9%, respectively, whereas the clinical progressive disease negative predictive value was 20%. Then, 6.9% of patients believed to have responded to the therapy, or not to have responded or worsened, actually had worsened by the end of the chemoradiotherapy.

Conclusions

Positive and negative predictive values, in particular for partial response and stable disease, of clinical evaluation of the response to chemoradiotherapy were not high enough to consider clinical evaluation accurate enough to make treatment decisions.

Reduction in the size of enlarged pelvic lymph nodes after chemoradiation therapy is associated with fewer lymph node metastases in locally advanced rectal carcinoma

PURPOSE

We hypothesized that a reduction in the size of the lymph nodes after neoadjuvant therapy for locally advanced rectal carcinoma would be associated with decreased lymph node metastases and/or a better prognosis.

METHODS

Between March 2006 and April 2012, 71 patients with primary rectal cancer received neoadjuvant chemoradiation therapy (CRT). For all lymph nodes 5 mm or larger in size, the major and minor axes were measured on CT scan images, and the product was calculated. The lymph node size was determined before and after CRT. The patients were divided into three groups based on the lymph node size before and after treatment. Group A exhibited a reduction in size of 60% or more, Group B a reduction of less than 60% and Group C had no lymph node enlargement before treatment.

RESULTS

The incidence of lymph node metastases on pathological examination was 15% in Group A and 50% in Group B (p = 0.006). The five-year disease-free survival in Group A was 84% compared with 78% in Group B (log rank p = 0.34). The five-year overall survival in Group A was 92% compared with 74% in Group B (log rank p = 0.088).

CONCLUSIONS

A reduction in the size of enlarged lymph nodes after neoadjuvant therapy may be a useful prognostic factor for recurrence and survival.

Sphincter-saving surgeries for rectal cancer: A single center study from Kashmir

Summary and Background Data:

The goals in the treatment of rectal cancer are cure, local control, and preservation of sphincter, bladder and sexual function. Surgical resection using sharp mesorectal dissection is important for achieving these goals.

Objectives:

The current treatment of choice for carcinoma rectum is sphincter saving procedures, which have practically replaced the previously done abdominoperineal resection. We performed a study in our institute to evaluate the surgical outcome and complications of rectal cancer.

Materials and Methods:

This prospectivestudy included 117 patients, treated for primary rectal cancer by low anterior resection (LAR) from May 2007 to December 2010. All patients underwent standard total mesorectal excision (TME) followed by restoration of continuity.

Results:

The peri-operative mortality rate was 2.5% (3/117). Post-operative complications occurred in 32% of the patients. After a median follow up of 42 months, local recurrences developed in 6 (5%) patients and distant metastasis in 5 (4.2%). The survival rate was 93%.

Conclusion:

The concept of total mesorectal excision (TME), advances in stapling technology and neoadjuvant therapy have made it possible to preserve the anal sphincter in most of the patients. Rectal cancer needs to be managed especially in a specialized unit for better results.

Can we predict pathologic complete response before surgery for locally advanced rectal cancer treated with preoperative chemoradiation therapy?

BACKGROUND

Pathologic complete response has been proven to have oncological benefits for locally advanced rectal cancer treated with chemoradiation therapy. The aims of this study are to analyze and determine the factors to predict pathologic complete response for patients treated with preoperative neoadjuvant therapy.

METHODS

Patients with biopsy-proven, locally advanced rectal cancer were treated neoadjuvantly followed by radical surgical resection. Tumors were re-assessed after completing chemoradiation, including pelvic magnetic resonance images, colonoscopic examination, and re-biopsy. The results of examination were compared with the final pathologic status.

RESULTS

A retrospective chart review of 166 patients was conducted. Twenty-five patients (15.1%) had pathologic complete response after chemoradiation. The 5-year overall survival rates were better in the complete response group than the residual tumor group (91.1% vs. 70.8%; P = 0.047), and there were also significant differences in the 5-year disease-free survival rates between these two groups (91.1% vs. 70.2%; P = 0.027). The prediction rates for pathologic complete response by re-biopsy, magnetic resonance images, and colonoscopy were 21.4%, 33.3%, and 53.8%, respectively. In addition, when we further combine the results of colonoscopic findings and re-biopsy, the prediction rate for pathologic complete response reached 77.8% (P = 0.009).

CONCLUSIONS

Combining the results of the re-biopsy and post-treatment colonoscopic findings, we can achieve a good prediction rate for pathologic complete response. Post-treatment magnetic resonance images are not useful tools in predicting tumor clearance following chemoradiation.

Oncological and functional outcomes of intersphincteric resection for low rectal cancer

BACKGROUND

The intersphincteric resection technique has been used to extend the opportunity for sphincter preservation in patients with very low rectal cancer. The aim of this study is to assess the long-term oncological and functional outcomes of intersphincteric resection.

METHODS

Patients with extraperitoneal rectal cancer were treated and retrospectively chart reviewed. The oncological and functional outcomes were evaluated. Comparisons of the overall disease-free survival and recurrence were analyzed for the different surgical procedures.

RESULTS

From July 2002 to August 2009, 162 patients with extraperitoneal rectal cancer were retrospectively chart reviewed. One-hundred one patients (62.3%) underwent low anterior resection, 26 patients (16%) received radical proctectomy and intersphincteric resection with coloanal anastomosis, and 23 (14.2%) had abdominoperineal resection. The sphincter preservation rate was 80%. In the intersphincteric resection group, overall survival rates at 3 and 5 y were 83% and 83%, and disease-free survival at 3 and 5 y were 82% and 76%, respectively. The mean stool frequency was 4.7 per 24 h. There were 38.1% of patients suffering from stool fragmentation, and 23.8% had nocturnal defecation. About one-third of the patients required antidiarrheal medications. Overall, 90.8% of patients were satisfied with the functional results of surgery.

CONCLUSIONS

Our data show intersphincteric resection for low rectal cancer is feasible and safe. Preoperative radiotherapy may negatively affect symptom-specific quality of life.

Long-term outcome in patients with a pathological complete response after chemoradiation for rectal cancer: a pooled analysis of individual patient data

BACKGROUND

Locally advanced rectal cancer is usually treated with preoperative chemoradiation. After chemoradiation and surgery, 15-27% of the patients have no residual viable tumour at pathological examination, a pathological complete response (pCR). This study established whether patients with pCR have better long-term outcome than do those without pCR.

METHODS

In PubMed, Medline, and Embase we identified 27 articles, based on 17 different datasets, for long-term outcome of patients with and without pCR. 14 investigators agreed to provide individual patient data. All patients underwent chemoradiation and total mesorectal excision. Primary outcome was 5-year disease-free survival. Kaplan-Meier survival functions were computed and hazard ratios (HRs) calculated, with the Cox proportional hazards model. Subgroup analyses were done to test for effect modification by other predicting factors. Interstudy heterogeneity was assessed for disease-free survival and overall survival with forest plots and the Q test.

FINDINGS

484 of 3105 included patients had a pCR. Median follow-up for all patients was 48 months (range 0-277). 5-year crude disease-free survival was 83.3% (95% CI 78.8-87.0) for patients with pCR (61/419 patients had disease recurrence) and 65.6% (63.6-68.0) for those without pCR (747/2263; HR 0.44, 95% CI 0.34-0.57; p<0.0001). The Q test and forest plots did not suggest significant interstudy variation. The adjusted HR for pCR for failure was 0.54 (95% CI 0.40-0.73), indicating that patients with pCR had a significantly increased probability of disease-free survival. The adjusted HR for disease-free survival for administration of adjuvant chemotherapy was 0.91 (95% CI 0.73-1.12). The effect of pCR on disease-free survival was not modified by other prognostic factors.

INTERPRETATION

Patients with pCR after chemoradiation have better long-term outcome than do those without pCR. pCR might be indicative of a prognostically favourable biological tumour profile with less propensity for local or distant recurrence and improved survival.

FUNDING

None.

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.

Radiotherapy in the treatment of resectable rectal adenocarcinoma

The goal of treatment is to cure whereas maintaining sphincter function and minimizing toxicity. Although the mainstay of the treatment is surgery, radiotherapy (RT) is used in a substantial proportion of patients depending on the location and extent of the tumor. The aim of this article is to discuss the role of RT in patients with resectable rectal adenocarcinoma. This article is a review of the pertinent literature. Results show that patients with T1N0 exophytic, well to moderately differentiated, mobile tumors < or = 3 cm in diameter may be treated with either transanal excision or endocavitary RT. The probability of cure with either approach is approximately 80% to 90% and depends on selection criteria. The advantages of endocavitary RT are that it is an outpatient procedure requiring, at most, local anesthesia and is suitable for elderly, infirm patients. The disadvantage is that few of these treatment units are available. Patients who experience a local-regional recurrence may be surgically salvaged. Patients who undergo transanal excision and have unfavorable pathologic findings including equivocal or close margins, poor differentiation, invasion of the muscularis propria, and/or endothelial-lined space invasion have a high risk of local-regional recurrence after surgery alone. The addition of postoperative RT improves the likelihood of cure from 85% to 90%. Patients presenting with unfavorable tumors that are borderline resectable with a transanal excision may be downstaged with preoperative RT and rendered suitable for a wide local excision. The addition of concomitant chemotherapy probably enhances downstaging and may improve the likelihood of sphincter preservation. Patients with T3 and/or N1 rectal cancers have a relatively high probability of local-regional recurrence after surgery alone. Preoperative RT and postoperative RT combined with adjuvant chemotherapy have been shown to significantly reduce the risk of local-regional recurrence and improve survival. Whether preoperative RT alone or combined with chemotherapy is more efficacious than postoperative chemoradiation remains unclear. Endocavitary RT or transanal excision is suitable for patients with T1N0 cancers. Depending on tumor location and extent, adjuvant RT may improve the probability of local-regional control and survival for patients with locally advanced rectal adenocarcinomas.

Extended total mesorectal excision in locally advanced rectal cancer (T4a) and the clinical role of MRI-evaluated neo-adjuvant downstaging

OBJECTIVE

To compare the clinical ability of MRl taken before and after neo-adjuvant treatment in locally advanced rectal cancer (LARC) to predict the necessary extension of TME (ETME) and the possibility to achieve a R0 resection.

METHOD

Prospective registration of 92 MRI evaluated T4a cancers undergoing elective surgery between 2002 and 2007 in a tertiary referral centre for multimodal treatment of rectal cancer.

RESULTS

MRI identified patients in need of neo-adjuvant treatment and predicted T-downstaging in 10% and N-downstaging in 59%. Seventy-nine percent R0 resections, 18% R1 and 3% R2 were obtained after ETME in 95% of the patients and TME in the rest. Higher tumour regression grade (TRG) was achieved in higher ypT-stage (P < 0.01). Preoperative chemo radiotherapy resulted in that more patients obtained TRG1-3 compared to those receiving radiotherapy (79% vs. 57%, P = 0.02). The pelvic wall was the area of failure in 70% of the R1 resections. Tumour cells outside the mesorectal fascia scattered within fibrosis was found in 18 TRG2-3 among 33 ypT4 tumours (55%).

CONCLUSION

MRl cannot discriminate tumour within fibrosis. Therefore, if a R0 resection is the goal, we advocate optimal surgery in accordance with the pre-treatment MRI. Post treatment MRI is a poor predictor of final histology and should not be relied upon to guide the extent of surgical resection. The study has initiated a new approach to histopathological classification of the removed specimen where we introduce a MRI assisted technique for investigating the areas at risk outside the mesorectal fascia in the specimen.

Residual treatment disparities after oncology referral for rectal cancer

BACKGROUND

Black patients with rectal cancer are considerably less likely than white patients to receive adjuvant therapy. We examined the hypothesis that the lower treatment rate for blacks is due to underreferral to medical and radiation oncologists.

METHODS

We used 1992-1999 Surveillance, Epidemiology, and End Results-Medicare data to identify elderly (> or = 66 years of age) patients who had been hospitalized for resection of stage II or III rectal cancer (n = 2716). We used chi(2) tests to examine associations between race and 1) consultation with an oncologist and 2) receipt of adjuvant therapy. We then used logistic regression to analyze the influence of sociodemographic and clinical characteristics (age at diagnosis, sex, marital status, median income and education in area of residence, comorbidity, and cancer stage) on black-white differences in the receipt of adjuvant therapy. All statistical tests were two-sided.

RESULTS

There was no statistically significant difference between the 134 black patients and the 2582 white patients in the frequency of consultation with a medical oncologist (73.1% for blacks vs 74.9% for whites, difference = 1.8%, 95% confidence interval [CI] = > 5.9% to 9.5%, P = .64) or radiation oncologist (56.7% vs 64.8%, difference = 8.1%, 95% CI = > 0.5% to 16.7%, P = .06), but blacks were less likely than whites to consult with both a medical oncologist and a radiation oncologist (49.2% vs 58.8%, difference = 9.6%, 95% CI = 0.9% to 18.2%, P = .03). Among patients who saw an oncologist, black patients were less likely than white patients to receive chemotherapy (54.1% vs 70.2%, difference = 16.1%, 95% CI = 6.0% to 26.2%, P = .006), radiation therapy (73.7% vs 83.4%, difference = 9.7%, 95% CI = 0.4% to 19.8%, P = .06), or both (60.6% vs 76.9%, difference = 16.3%, 95% CI = 4.3% to 28.3%, P = .008). Patient and provider characteristics had minimal influence on the racial disparity in the use of adjuvant therapy.

CONCLUSION

Racial differences in oncologist consultation rates do not explain disparities in the use of adjuvant treatment for rectal cancer. A better understanding of patient preferences, patient-provider interactions, and potential influences on provider decision making is necessary to develop strategies to increase the use of adjuvant treatment for rectal cancer among black patients.

An interval >7 weeks between neoadjuvant therapy and surgery improves pathologic complete response and disease-free survival in patients with locally advanced rectal cancer

BACKGROUND

We assessed whether the time interval between neoadjuvant therapy and surgery affects the operative and postoperative morbidity and mortality, the pathologic complete response (pCR) rate, and disease recurrence in locally advanced rectal cancer.

METHODS

One-hundred and thirty-two patients with locally advanced low- and mid-rectal cancer underwent neoadjuvant chemoradiation followed by radical resection (October 2000 to December 2006). Data on the neoadjuvant regime, neoadjuvant-surgery interval, final pathology, type of operation, operative time, intraoperative blood transfusions, postoperative complications, length of hospital stay, disease recurrence, and mortality were reviewed. The patients were divided into two groups according to the neoadjuvant-surgery interval: </=7 weeks (group A, n = 48), and >7 weeks (group B, n = 84).

RESULTS

The groups were demographically comparable except for the group A patients being younger at operation. The median interval between chemoradiation and surgery was 56 days (range 13-173 days). Thirty-seven patients (28%) had a pCR and near pCR. Fifty three patients (40%) had complications. There was no in-hospital mortality. Surgery type, operative time, number of intraoperative blood transfusions, postoperative complications, and length of hospitalization were not influenced by the interval length. The pCR and near pCR rates were higher with longer interval: 17% in group A, 35% in group B (P = 0.03). Patients operated at an interval >7 weeks had significantly better disease-free survival (P = 0.05).

CONCLUSIONS

A neoadjuvant-surgery interval >7 weeks was associated with higher rates of pCR and near pCR, decreased recurrence and improved disease-free survival.

Is final TNM staging a predictor for survival in locally advanced rectal cancer after preoperative chemoradiation therapy?

BACKGROUND

Neoadjuvant chemoradiation therapy has improved the local control rate and overall survival in locally advanced rectal cancers. The purpose of this retrospective study is to evaluate the correlation between the final pathologic stage and survival in these patients.

METHODS

Patients with biopsy-proven rectal carcinoma, pretreatment staging by magnetic resonance imaging such as T3 or T4 tumors, or node-positive disease were treated with preoperative concomitant 5-fluorouracil-based chemotherapy and radiation, followed by radical surgical resection. Clinical outcome with survival, disease-free survival, recurrence rate, and local recurrence rate were compared with each T and N findings using the American Joint Committee on Cancer Tumor-Node-Metastasis (TNM) staging system.

RESULTS

A total of 248 patients were enrolled in this study. Overall survival and disease-free survival at 1, 3, and 5 years were 97.1, 92, and 89.9% and 87.5, 71.1, and 69.5%, respectively. Thirty-six patients (14.5%) had a pathologic complete response after neoadjuvant therapy. The recurrence rate was significantly different between the pathologic complete response group and residual group (5.6 vs 31.1%; P = .002). Five-year disease-free survival was significantly better in the complete response group than the residual tumor group (93 vs 66%; P = .0045). There was no statistical difference in survival or locoregional recurrence rate between these two groups.

CONCLUSIONS

Posttreatment pathologic TNM stage is correlated to disease-free survival and tumor recurrence rate in locally advanced rectal cancer after preoperative chemoradiation. Also, pathologic complete response to neoadjuvant treatment has its oncologic benefit in both overall recurrence and disease-free survival.

Neoplastic mesorectal microfoci (MMF) following neoadjuvant chemoradiotherapy: clinical and prognostic implications

BACKGROUND

Neoplastic microfoci have frequently been found in the mesorectum, with poor outcome. In this study, incidence and clinical significance of mesorectal microfoci (MMF) were analyzed in patients operated on for rectal cancer following neoadjuvant chemoradiation.

METHODS

A case series of 68 patients with extraperitoneal rectal cancer treated with neoadjuvant chemoradiation and surgery (including total mesorectal excision) were investigated for presence of neoplastic MMF.

RESULTS

MMF were found in 26 cases (38.2%). Increasing incidence of microfoci was statistically related to pathologic involvement of the bowel wall (P = 0.0006), Mandard's tumor regression grading (P = 0.0006), and pathologic neoplastic mesorectal involvement (P < 0.00001). None of the nine patients with complete tumor disappearance displayed both microfoci and lymph node metastasis. Only one local recurrence developed in a patient with multiple MMF. One out of nine pT0 or TRG1 patients (11.1%) had distant metastases compared with 15 out of 59 pT1-4 or TRG2-5 (25.4%, P = 0.70).

CONCLUSIONS

A remarkable incidence of MMF was found following chemoradiation. However, when this therapy induced complete regression of primary tumor (pT0-TRG1), we found that node metastases and neoplastic MMF also disappeared. These features should be confirmed to assess the impact of these microfoci in treatment decision making in rectal cancers.

Analysis of clinical outcomes and prognostic factors of neoadjuvant chemoradiotherapy combined with surgery: intraperitoneal versus extraperitoneal rectal cancer

Neoadjuvant chemoradiotherapy (CRT) is a widely purposed and performed treatment for rectal cancer. Downstaging effects possibly enhance the rate of curative surgery and may enable sphincter preservation in low-lying tumours. The current study examines the clinical outcomes in patients enrolled in a neoadjuvant CRT-surgery protocol for rectal cancer, distinguishing between intraperitoneal and extraperitoneal cancer. From 1994 to 2003, 58 patients with a primary diagnosis of rectal cancer were enrolled in a single-centre, not randomized study based on 5-week sessions of radiotherapy associated with a 30-day protracted venous 5-FU infusion followed by surgical resection. The study population was divided into two groups according to the localization of the tumour: 18 intraperitoneal and 40 extraperitoneal (EPt). Fifty-eight patients were treated with neoadjuvant CRT and surgery. Overall mortality rate was 25.9%, no deaths were recorded during hospitalization; 10 patients (all EPt) died because of recurrence. Significant differences in disease-free survival and overall survival rates were found between intraperitoneal vs. extraperitoneal tumours (P = 0.006), both intraperitoneal vs. extraperitoneal tumours N(0) (P = 0.04 and P < 0.05) and intraperitoneal vs. extraperitoneal tumours N(+) (P < 0.05). We diagnosed all local recurrence and liver metastasis in extraperitoneal tumours (t = 0.02 and t = 0.04), and only one case of lung metastasis arose from intraperitoneal cancer. Extraperitoneal tumours could be more aggressive than intraperitoneal ones, spreading more precociously, and/or less responsive to the neoadjuvant CRT because of their localization rather than biological differences. Aside from lymph node status, the location of the tumour with respect to the peritoneum border, is also a prognostic factor of survival in rectal cancer treated by neoadjuvant CRT and surgery.

Instrumental clinical restaging, pathological evaluation, and tumor regression grading: how to assess the response to neoadjuvant chemoradiotherapy for rectal cancer

INTRODUCTION

The object of neoadjuvant chemoradiotherapy regimens is a downstaging or downsizing of advanced rectal tumor to increase the rate of curative resection and reduce loco-regional failure. A reliable method of assessing response to adjuvant therapies is required to help standardize the assessments of new multimodality therapies. The purpose of this study was to evaluate the role played by tumor regression grading on the evaluation of pathological response to chemoradiotherapy, compared with both the predicting value of the clinical response to neoadjuvant therapy and pathologic response evaluation.

METHODS

From 1994 to 2003, 58 patients with a primary diagnosis of rectal cancer were studied at our department and enrolled in a single center, not randomized study based on 5-week sessions of radiotherapy associated with a 30-day 5-fluorouracil (FU) infusion, followed by surgical resection. Instrumental restaging and routine histological examination, including tumor regression grading, were performed to asses the response to neoadjuvant therapy.

RESULTS

The cCR rate corresponds to pCR rate, while a 3.5% of cPR and a 3.4% of cSD corresponded to a pPD. cPR and cSD show a PPV of 92.8% and 90.9% respectively, while cPD NPV is 20%. No case was found with no regression (grade 0). Tumor regression was defined grade 1 in 24.5% of cases, grade 2 was found in 58.5% of cases, 7.5% were grade 3, and 9.5% showed complete regression (grade 4). Pathologic response resulted to be associated with regression grade (p=0.006). Tumor regression grading is an independent variable for pT (p=0.0002), pN status (p=0.00004), pathologic staging (p=0.000001) and local recurrence (p=0.003).

CONCLUSION

Our results lead us to consider only pathologic evaluation to determine the response to neoadjuvant treatment: the application of tumor regression grading on the specimens obtained after combined neoadjuvant chemoradiotherapy and surgery is useful to plan a better therapeutic strategy on the ground of a quantitative evaluation of the response to neoadjuvant treatment; it shows it is an important comparable pathological feature, useful in comparing different protocols' results and differences between patient's response as well as prognostic factors.

Diagnostic and therapy of locally advanced rectal cancer

The aim of the study was to check the results of the protocol with neoadjuvant chemoirradiation for the treatment of locally advanced rectal cancer. The value of preoperative methods for staging of rectal cancer was also studied. In the period 1st of June 2000 - 31st of December 2005, 116 patients were included into the study, all with histologically proven rectal cancer up to 12 cm from anal verge and all with T3/T4 No-2 M0 stage. Median follow up was 48 months. Operability rate was 90,1%, local recurrency 12%, and survival 78%, though only 66% without sign of local or distant recurrency.

Racial disparities in late survival after rectal cancer surgery

BACKGROUND

African-American patients experience higher mortality than Caucasian patients after surgery for most common cancer types. Whether longterm survival after rectal cancer surgery varies by race is less clear.

STUDY DESIGN

Using 1992 to 2003 Surveillance, Epidemiology, and End Results (SEER)-Medicare data, we examined race and longterm survival among African-American and Caucasian rectal cancer patients undergoing resection. We identified racial differences in patient characteristics, structure, and processes of care. We then assessed mortality using a Cox proportional hazards model, sequentially adding variables to explore the extent to which they attenuated the association between race and mortality.

RESULTS

African-American patients had a substantially poorer overall survival rate than Caucasian patients did. Five-year survival rates were 41% and 50%, respectively (p < 0.0001). African Americans were younger (p=0.006), more likely to reside in low income areas (p < 0.0001), and had more baseline comorbid disease (p < 0.0001). They were also more likely to be diagnosed emergently (p < 0.001) and with more advanced cancer (p < 0.001). Accounting for demographic and clinical characteristics reduced the mortality difference, although it remained pronounced (hazard ratio=1.13, CI=1.01 to 1.26). African Americans were more likely to be treated by low volume surgeons and less likely to receive adjuvant therapy (48.6% versus 60.9%, p < 0.0001). After adjusting for provider variables, the hazard ratio for mortality by race was additionally attenuated and became statistically nonsignificant (hazard ratio=1.05, CI=0.92 to 1.20).

CONCLUSIONS

Poorer longterm survival after rectal cancer surgery among African Americans is explained by measurable differences in processes of care and patient characteristics. These data suggest that outcomes disparities could be reduced by strategies targeting earlier diagnosis and increasing adjuvant therapy use among African-American patients.

Neoplastic mesorectal microfoci (MMF) following neoadjuvant chemoradiotherapy: clinical and prognostic implications

BACKGROUND

Neoplastic microfoci have frequently been found in the mesorectum, with poor outcome. In this study, incidence and clinical significance of mesorectal microfoci (MMF) were analyzed in patients operated upon for rectal cancer following neoadjuvant chemoradiation.

METHODS

A case series of 68 patients with extraperitoneal rectal cancer, treated with neoadjuvant chemoradiation and surgery (including total mesorectal excision), was investigated for the presence of neoplastic MMF.

RESULTS

Mesorectal microfoci were found in 26 cases (38.2%). Increasing incidence of microfoci was statistically related to pathologic involvement of bowel wall (P = 0.0006), Mandard's tumor regression grading (P = 0.0006) and pathologic neoplastic mesorectal involvement (P < 0.00001). None of the nine patients with complete tumor disappearance displayed both microfoci and lymph node metastasis. Only one local recurrence developed in a patient with multiple MMF. Out of 9 pT0 or TRG1 patients, 1 (11.1%) had distant metastases, compared to 15 out of 59 pT1-4 or TRG2-5 (25.4%, P = 0.70).

CONCLUSIONS

A remarkable incidence of MMF was found following chemoradiation. However, when this therapy induces complete regression of primary tumor (pT0-TRG1), node metastases and neoplastic MMF could also disappear, as shown in our cases. These features should be confirmed because they could significantly impact the treatment decision-making of rectal cancers.

Chemotherapy regimen predicts steatohepatitis and an increase in 90-day mortality after surgery for hepatic colorectal metastases

PURPOSE

Chemotherapy before resection of hepatic colorectal metastases (CRM) may cause hepatic injury and affect postoperative outcome.

PATIENTS AND METHODS

Four hundred six patients underwent hepatic resection of CRM between 1992 and 2005. Pathologic review of the nontumorous liver was performed using established criteria for steatosis, steatohepatitis, and sinusoidal injury. The effect of chemotherapy and liver injury on perioperative outcome was analyzed.

RESULTS

One hundred fifty-eight patients (38.9%) received no preoperative chemotherapy, whereas 248 patients (61.1%) did. The median duration of chemotherapy was 16 weeks (range, 2 to 70 weeks). Chemotherapy consisted of fluoropyrimidine-based regimens (fluorouracil [FU] alone, 15.5%; irinotecan plus FU, 23.1%; and oxaliplatin plus FU, 19.5%) and other therapy (3.0%). On pathologic analysis, 36 patients (8.9%) had steatosis, 34 (8.4%) had steatohepatitis, and 22 (5.4%) had sinusoidal dilation. Oxaliplatin was associated with sinusoidal dilation compared with no chemotherapy (18.9% v 1.9%, respectively; P < .001; odds ratio [OR] = 8.3; 95% CI, 2.9 to 23.6). In contrast, irinotecan was associated with steatohepatitis compared with no chemotherapy (20.2% v 4.4%, respectively; P < .001; OR = 5.4; 95% CI, 2.2 to 13.5). Patients with steatohepatitis had an increased 90-day mortality compared with patients who did not have steatohepatitis (14.7% v 1.6%, respectively; P = .001; OR = 10.5; 95% CI, 2.0 to 36.4).

CONCLUSION

Steatohepatitis is associated with an increased 90-day mortality after hepatic surgery. In patients with hepatic CRM, the chemotherapy regimen should be carefully considered because the risk of hepatotoxicity is significant.

Prognostic value of tumour regression grading and depth of neoplastic infiltration within the perirectal fat after combined neoadjuvant chemo-radiotherapy and surgery for rectal cancer

OBJECTIVE

To evaluate histological variables correlated with pathological response to chemo-radiotherapy protocols for rectal cancer and with local recurrence and survival.

METHODS

From 1994 to 2003, 58 patients with rectal cancer were enrolled in a non-randomised study based on standardised treatment with radiotherapy, 5-fluorouracil, and surgical resection, followed by histological examination, including tumour regression grading and depth of neoplastic infiltration within the perirectal fat. All patients were followed up. Mean (SD) length of follow up was 55.3 (28.1) months, range 5 to 108.

RESULTS

No case was found with no regression (grade 0). Tumour regression was defined as grade 1 in 24.5% of cases, grade 2 in 58.5%, grade 3 in 7.5%, and grade 4 (complete regression) in 9.5%. Neoplastic infiltration of >4 mm within the perirectal fat was found in 25.6% of cases in grade 1, 55.8% in grade, 2.7% in grade 3, and 11.6% in grade 4. In 80% cases of pT4 depth of neoplastic infiltration within the perirectal fat was >4 mm (100% were pN+), and the same spread was also found in 53.4% of pT2 and 86.2% of pT3. Pathological response was associated with regression grade (p = 0.006) and depth of neoplastic infiltration within the perirectal fat (p = 0.04). Tumour regression grading was an independent variable for pT (p = 0.0002), pN status (p = 0.00004), pathological staging (p = 0.000001), and local recurrence (p = 0.003).

CONCLUSIONS

Involvement of the lateral resection margins correlates with a poor prognosis and indicates the likelihood of local recurrence of rectal cancer. Tumour regression grading and the depth of neoplastic infiltration within the perirectal fat are important prognostic factors that need to be evaluated routinely.

Tumor response to neoadjuvant chemoradiation therapy for rectal adenocarcinoma is mediated by p53-dependent and caspase 8-dependent apoptotic pathways

BACKGROUND

We tested the hypothesis that rectal tumors are most responsive to neoadjuvant therapy if they possess p53 and/or caspase 8 activity.

PATIENTS AND METHODS

Fifty patients diagnosed with biopsy-proven rectal cancer underwent neoadjuvant chemoradiation therapy consisting of 5-fluorouracil (300 mg/m(2) daily) and radiation (4,500 cGy). Endorectal ultrasonography was performed before and after neoadjuvant therapy along with digital rectal examination and/or sigmoidoscopy for staging purposes and to evaluate response to therapy. All patients underwent resection with specimens submitted for gross and microscopic review. Pretreatment biopsy specimens were subjected to immunohistochemical staining for mutated p53 and caspase 8 bioactivity.

RESULTS

The study population consisted of 32 men and 18 women. There were 17 complete responses (CRs; 34%), 17 partial responses (PRs; 34%), and 16 cases of no response (NR; 32%). There were 10 stage I tumors (20%), 22 stage II tumors (44%), and 18 stage III tumors (36%) in the cohort at the time of initial diagnosis. p53 protein staining (ie, mutated p53) was positive in 31 tumors (62%; CR, n = 8; PR, n = 11; NR, n = 12); caspase 8 positivity was apparent in 30 specimens (60%; CR, n = 13; PR, n = 13; NR, n = 4). In terms of pretreatment predictions, we scored 3 separate levels of response (CR, 3; PR, 2; NR, 1) and compared them with the expected responses (ie, p53 positivity and caspase 8 negativity should yield NR, whereas all other combinations should yield responses). Wilcoxon 2-sample tests yielded a 1-sided P value of 0.007.

CONCLUSION

The present study highlights a possible mechanism for tumor response to neoadjuvant manipulation, namely that dual mechanisms for apoptotic cell death are working in concert to cause tumor regression; one is p53 transcription-dependent, and the other is p53 transcription-independent.

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.

Preoperative chemotherapy and radiotherapy for locally advanced rectal cancer

BACKGROUND

The adjuvant treatment of rectal cancer is a rapidly evolving field. The standard approach is a combination of chemotherapy and radiotherapy, with the optimal treatment combination and sequencing yet to be determined. Here, we report our early experience of preoperative chemotherapy and radiotherapy (CRT) in locally advanced rectal cancer at Radiation Oncology Victoria to determine its efficacy and the rate of sphincter preservation.

METHODS

Sixty-nine patients (46 men and 23 women) with locally advanced rectal cancer (T3-4 or N1) were treated with preoperative CRT followed by surgical resection of disease. Chemotherapy consisted of either bolus or continuous venous infusion of 5-fluorouracil (5-FU). Radiotherapy to a dose of 45 Gy was delivered to the pelvis followed by a boost of 5.4-14.4 Gy in the majority of patients. Surgical resection was carried out 4-8 weeks following completion of preoperative CRT. Univariate and multivariate analyses were performed to examine variables that may influence local recurrence and overall survival rates.

RESULTS

All patients underwent a complete macroscopic resection, including the three patients that had unrecognized distant metastases discovered at the time of operation. Only two patients had microscopic residual disease. Sphincter preservation was achieved in 16 of 25 patients who were thought to require an abdominoperineal resection. Tumour and/or nodal downstaging were achieved in 47 patients (68%), with a pathological complete response in 12 (17%). At a median follow up of 29 months post-surgery, five patients (7.2%) have developed a local recurrence. Overall 21 patients (30%) have progressed and 12 (18%) have died. Treatment-related toxicity was acceptable and there was no treatment-related mortality. There was no significant relationship found between the pathological response to treatment and any clinical endpoint.

CONCLUSIONS

Our results confirm the high response rates and acceptable toxicity of preoperative treatment. Further studies are required to better define the impact of preoperative chemotherapy and radiotherapy on long-term outcomes.

Interpretation of magnetic resonance imaging for locally advanced rectal carcinoma after preoperative chemoradiation therapy

PURPOSE

Neoadjuvant concomitant chemoradiotherapy has been used in cases of locally advanced rectal cancer to preserve sphincter function, decrease local recurrence, and improve survival. Preoperative staging is essential for planning and providing optimal therapy. The purpose of this study is to determine the accuracy of staging with magnetic resonance imaging and to define any factors that interfere in interpretation of images obtained after preoperative chemoradiation therapy.

METHODS

Thirty-six patients with biopsy-proven, locally advanced rectal cancer were treated with preoperative concomitant 5-fluorouracil-based chemotherapy and radiation, followed six to eight weeks later by radical surgery. Preoperative magnetic resonance images were reinterpreted by one radiologist and the results compared with histopathologic staging.

RESULTS

T-level downstaging occurred in 10 of 36 patients (28 percent), and N-level downstaging occurred in 29 of 36 patients (80 percent) after completion of chemoradiation therapy. Pathologic complete remission after chemoradiotherapy occurred in five patients (12 percent). Of the 36 patients, 17 (47 percent) were overstaged and 2 (6 percent) were understaged in T-level, whereas 10 patients (28 percent) were overstaged and 3 patients (8 percent) were understaged in N-level. The accuracy of magnetic resonance imaging for determining depth of wall invasion was 47 percent, with 64 percent accuracy for nodal staging.

CONCLUSIONS

Magnetic resonance imaging is commonly used in staging of pelvic malignancies because of its fine resolution, but chemoradiotherapy may decrease its accuracy. Thickening of the rectal wall after radiation by marked fibrosis, and peritumoral infiltration of inflammatory cells and vascular proliferation may contribute to overestimation of stage. By contrast, pathologic residual cancer beneath normal mural structure after chemoradiation therapy may result in understaging of rectal cancer.

Long-term results using local excision after preoperative chemoradiation among selected T3 rectal cancer patients

PURPOSE

To assess the pelvic failure among patients with T3 rectal cancer treated with local excision after preoperative chemoradiation.

METHODS AND MATERIALS

Between January 1990 and June 2002, 431 patients with clinically staged T3 rectal cancer were treated with preoperative chemoradiation followed by surgical resection. Full-thickness local excision [Kraske (n = 3) or a transanal excision (n = 23)] was performed in 26 patients because of patient refusal of abdominoperineal resection (APR) (n = 13), medical comorbidity (n = 4), physician preference after a complete clinical response (n = 6), and other reasons (n = 3). All patients were treated with continuous-infusion 5-fluorouracil (5-FU) (300 mg/m(2) Monday to Friday) and concomitant pelvic radiation (45 Gy in 25 fractions with a 3-field belly board technique). Ten local-excision patients received a concomitant boost during the last week of therapy (1.5-Gy second daily fractions) for a total dose of 52.5 Gy. Similar preoperative treatment was followed by total mesorectal excision in 405 patients. Among the local-excision patients, the median tumor size was 3.5 cm (range, 0.5-7 cm). Well-differentiated or moderately-differentiated histology was present in all but 3 cases, and endoscopic ultrasound staging examination was performed in 25 of 26 patients. Based on CT findings, 1 patient was node positive. The median circumference involved by tumor was 33%, (20%-75%). The median distance from the anal verge was 3 cm (range, 1-8 cm).

RESULTS

The mean follow-up was 46 months (range, 5-109 months) in the local-excision group. In the local-excision group, 19 of 26 patients had only residual scarring noted on digital rectal examination and rigid proctoscopy before surgery. Fourteen patients (54%) had a complete histologic response to chemoradiation, 9 patients (35%) had microscopic residual disease, and 3 patients (12%) had gross residual disease. Two intrapelvic recurrences occurred at 76 and 20 months among the 26 patients treated with local excision (6% 5-year actuarial pelvic recurrence rate). This rate compared with an 8% 5-year actuarial pelvic recurrence rate among T3 patients treated with mesorectal excision and a 6% pelvic recurrence rate in the subgroup of mesorectal-excision patients with a complete clinical response to preoperative chemoradiation. One additional local-excision patient recurred in an inguinal lymph node after local excision and subsequently died of metastatic disease. A total of 2 local-excision patients died of metastatic rectal cancer. Actuarial overall survival at 5 years was 86% in the local-excision group compared with 81% among mesorectal-excision patients (p = NS), and 85% in patients with a complete clinical response to chemoradiation followed by mesorectal excision by APR or LAR (p = NS).

CONCLUSIONS

In an experience stimulated by patient refusal of APR, highly selected patients who responded well to conventional external-beam radiotherapy (CXRT) were selected to undergo local excision. Most of these patients had pathologic complete response. Local control and survival rates are comparable to those achieved with chemoradiation followed by mesorectal excision. This strategy should be prospectively studied in a group of patients with low rectal cancer who have no clinical evidence of tumor after chemoradiation.

Treatment outcomes in locally advanced colorectal carcinoma

BACKGROUND: Locally advanced colorectal cancers form a distinct subgroup where contiguous organs could be involved without distant metastases and so may be amenable to curative surgical resection. It was our objective to report our experience in treating six such patients with operable locally advanced colorectal carcinomas. METHODS: We retrospectively reviewed the case notes of 47 patients who were diagnosed with colorectal cancers at M S Ramaiah Medical Teaching Hospital between the years 1996 - 2001. Six patients were identified with T4 lesions, adjacent organ involvement and with no nodal involvement. The treatments and outcomes for these patients were then reviewed. RESULTS: Two of three patients with rectal malignancies who underwent pelvic exenteration succumbed to disease recurrence within the first 18 months. One of the three patients with colonic cancers died of non malignant causes. The other two are disease free till date. CONCLUSIONS: Aggressive multivisceral resections for locally advanced colonic cancers might be appropriate. Rectal cancers when locally advanced may be considered for pelvic exenteration, but a more guarded prognosis may apply.

Preoperative chemoradiation for locally advanced rectal cancer: rationale, technique, and results of treatment

Over the past decade, 392 patients with stage II and III rectal cancer have been managed with preoperative chemoradiation and surgery at the M. D. Anderson Cancer Center (MDACC). Aggressive surgical techniques such as total mesorectal excision, proctectomy with coloanal anastamosis, and multivisceral excisions have been used. Initial pelvic chemoradiation is also used in patients who present with metastases. Preoperative chemoradiation followed by surgery has resulted in excellent sphincter preservation (SP) and pelvic control with minimal acute, perioperative, and late morbidity. SP has been achieved in greater numbers of patients over the past 3 years due to the increased use of coloanal anastamosis in very low tumors. There has been no increase in pelvic failure or perioperative morbidity with this practice. Patients with clinical T4 disease have significantly worse pelvic control. An assessment of the impact of CB on pelvic control and survival requires further follow-up. Poor differentiation and poor response to preoperative therapy predict a worse overall survival. Durable symptom control without colostomy has been achieved using initial chemoradiation in patients who present with metastases. Aggressive bowel management and skin care can minimize hospitalization and treatment interruption due to acute toxicity. Multidisciplinary therapy using preoperative chemoradiation and aggressive surgery has resulted in excellent SP and pelvic control. However, more effective systemic therapies are needed, especially for patients who do not respond well to preoperative chemoradiation.

Predicting the node-negative mesorectum after preoperative chemoradiation for locally advanced rectal carcinoma

Preoperative chemoradiation therapy (CRT) in patients with locally advanced rectal cancer allows for radical surgery with sphincter preservation in many patients. To determine whether patients downsized with preoperative CRT may be potential candidates for local excision, we investigated residual disease patterns after neoadjuvant treatment. A retrospective analysis was carried out of patients with T3 or T4 rectal adenocarcinoma who were treated with neoadjuvant CRT. Clinical and pathologic data were analyzed to (1). determine the response rates to preoperative CRT in the tumor bed and regional nodal basin and (2). identify the incidence of residual disease in the mesorectum in patients downsized to <or=T2. A total of 219 patients met the inclusion criteria. Preoperatively 193 patients (88%) were staged as T3, and 99 patients (47%) had clinical N1 disease. The pathologic complete response rate was 20% (43 of 219 patients). T stage was downsized in 64% of the patients (140 of 219), and 69% (67 of 97) of the patients with clinical N1 disease were rendered node negative. Seventeen percent (21 of 122) of patients downsized to <or=T2 had residual disease in the mesentery. With a median follow-up of 40 months, 182 patients (83%) remain alive and free of disease. Nine patients (4.1%) have had a local recurrence. Although tumor response rates to preoperative CRT within the bowel wall and lymph node basin are similar, one in six patients with pT0-2 tumors will have residual disease in the rectal mesentery and nodes. Despite a substantial reduction in tumor volume with neoadjuvant CRT, local excision should be recommended with caution in patients with locally advanced rectal cancer.

Preoperative chemoradiation for locally advanced rectal adenocarcinoma-the University of Florida experience

To evaluate the efficacy of preoperative radiotherapy alone or combine with chemotherapy. Between 1975 to 1997, 318 patients with locally advanced rectal adenocarcinomas were treated with preoperative radiation therapy. Between 1991 and 1997, approximately 60% of patients received fluorouracil (5-FU)-based adjuvant chemotherapy. Patients treated since 1991 had improved downstaging compared with those treated prior to 1991. Patients treated between 1991 and 1997 were also more likely to undergo a sphincter preserving surgical procedure. Preoperative chemoradiation probably results in improved downstaging and survival compared with preoperative irradiation alone.

The addition of continuous infusion 5-FU to preoperative radiation therapy increases tumor response, leading to increased sphincter preservation in locally advanced rectal cancer

PURPOSE

To compare the outcome from preoperative chemoradiation (CXRT) and from radiation therapy (RT) in the treatment of rectal cancer in two large, single-institutional experiences.

PATIENTS AND METHODS

Between 1978 and 1995, 403 patients with localized, nonmetastatic, clinically staged T3 or T4 rectal cancer patients were treated with preoperative RT alone at two institutions. Patients at institution 1 (n = 207) were treated with pelvic CXRT exclusively, and patients at institution 2 were treated (except for 8 given CXRT) with pelvic RT alone (n = 196). In addition, a third group (n = 61) was treated with CXRT at institution 2 between 1998 and 2000 after a policy change. Both institutions delivered 45 Gy in five fractions as a standard dose, but institution 2 used 20 Gy in five fractions in selected cases (n = 26). At both institutions, concurrent chemotherapy consisted of a continuous infusion of 5-fluorouracil (5-FU) at a dosage of 1500 mg/m(2)/week. The end points were response, sphincter preservation (SP), relapse-free survival (RFS), pelvic disease control (PC), and overall survival (OS).

RESULTS

Median follow-up was 63 months for all living patients at institution 1 and in the primary group of institution 2. Multivariate analysis of the patients in these groups showed that the use of concurrent chemotherapy improved tumor response (T-stage downstaging, 62% vs. 42%, p = 0.001, and pathologic complete response, 23% vs. 5% p < 0.0001), but did not significantly improve LC, RFS, or OS. Follow-up for the secondary group at institution 2 was insufficient to allow the analysis of these endpoints. In the subset of patients receiving 45 Gy who had rectal tumors < or /=6 cm from the anal verge (institution 1: n = 132; institution 2 primary: n = 79; institution 2 secondary: n = 33), there was a significant improvement in SP with the use of concurrent chemotherapy (39% at institution 1 compared with 13% in the primary group at institution 2, p < 0.0001). A logistic regression analysis of clinical prognostic factors indicated that the use of concurrent chemotherapy independently influenced SP in these low tumors (p = 0.002). This finding was supported by a 36% SP rate in the secondary group at institution 2. Thus SP increased after the addition of chemotherapy at institution 2.

CONCLUSIONS

The use of concurrent 5-FU with preoperative radiation therapy for T3 and T4 rectal cancer independently increases tumor response and may contribute to increased SP in patients with low rectal cancer.

Response to preoperative chemoradiation increases the use of sphincter-preserving surgery in patients with locally advanced low rectal carcinoma

BACKGROUND

Although controversial, some believe that preoperative chemoradiation increases the use of sphincter-preserving surgery in low rectal carcinoma patients. This article investigates the relationship between objective tumor response and sphincter preservation in low rectal carcinoma patients.

METHODS

The authors reviewed the records of 238 patients with T3 or T4 low rectal carcinoma (< or = 6 cm from the anal verge) who underwent preoperative pelvic chemoradiation (45 Gy/25 fractions/5 weeks, n = 182 or 52.5 Gy/30 fractions/5 weeks, n = 56 with continuous infusion 5-fluorouracil at 300 mg/m(2), Monday to Friday) followed by mesorectal (n = 223) or local excision (n = 15). A logistic regression analysis was used to analyze the influence of objective tumor response (defined as complete clinical response) and other prognostic factors on sphincter preservation. Because degrees of partial response could not be objectively defined retrospectively, the influence of partial response on sphincter preservation could not be evaluated.

RESULTS

Overall, 49% of patients (117 of 238) had sphincter-preserving surgery. The clinical complete response rate was 47%. Independent predictors of sphincter preservation included the year of surgery, tumor distance from the anal verge, circumferential tumor involvement, and response to chemoradiation. The sphincter preservation rate increased over the period of the study (from 28% [December 1989 to December 1992] to 44% [January 1993 to December 1996] to 67% [January 1997 to December 2000]). The difference in the rates of sphincter preservation according to response was most striking among patients with tumors 3 cm or less from the anal verge (44% vs. 22%, P = 0.01). The pelvic disease recurrence rate among patients undergoing sphincter-preserving surgery has been less than 10% since January 1993 and was not statistically different between the groups treated from January 1993 to December 1996 and from January 1997 to December 2000.

CONCLUSIONS

There has been an increase in the use of sphincter-preserving surgery without an increase in pelvic disease recurrence over the past decade. Although not necessary for sphincter preservation, clinical response to preoperative chemoradiation independently contributed to sphincter-preserving surgery, particularly in patients with low rectal tumors.

Transanal excision of locally advanced rectal cancers downstaged using neoadjuvant chemoradiotherapy

BACKGROUND

Our institution has previously demonstrated a survival advantage conferred by preoperative neoadjuvant therapy for locally advanced rectal cancers. We now report our results using transanal excision as definitive surgical therapy in a selected group of patients who experienced significant downstaging of T3 rectal cancers after neoadjuvant therapy.

STUDY DESIGN

Seventy-four patients diagnosed with locally advanced (T3) rectal cancers were treated with neoadjuvant chemoradiotherapy. After neoadjuvant therapy, 11 (14.9%) patients who had significant downstaging of their tumors were selected to undergo transanal excision of their residual rectal cancers. Intraoperative cryostat evaluation was used to confirm negative margin status, and all patients were subsequently followed with routine endoscopy, transrectal ultrasonography, and digital rectal examinations.

RESULTS

Tumors were located between 1 cm and 7 cm from the anal verge (mean 4.3 +/- 0.6 cm), and were located in lateral, anterior, and posterior positions. Mean followup was 55.2 +/- 8.9 months (median 47.9 months). Imaging studies using CT, MRI, transrectal ultrasonography, or combination demonstrated suspicious lymph nodes in three patients. After neoadjuvant therapy, these lymph nodes were no longer demonstrated in two patients. There were no local recurrences, nodal metastases, or operative mortalities. One patient (9%) developed distant metastases (pulmonary nodules), and remains alive 30 months after transanal excision. One patient (9%) experienced sphincter laxity, which was successfully repaired, and is now asymptomatic. One patient (9%) developed postoperative urgency that resolved spontaneously.

CONCLUSIONS

In patients who have initial bulky (T3) lesions, and experience significant downstaging after neoadjuvant chemoradiotherapy, transanal excision appears to be a safe and effective treatment, preserving sphincter function and avoiding laparotomy.

TP53 genotype but not p53 immunohistochemical result predicts response to preoperative short-term radiotherapy in rectal cancer

OBJECTIVE

To evaluate and compare the predictive power of p53 gene analysis versus p53 immunohistochemical staining in terms of response to preoperative short-term radiotherapy using 25 Gy in operable rectal cancer.

SUMMARY BACKGROUND DATA

Recent studies show that p53 may be a determinant of radiosensitivity being required for induction of apoptosis in case of radiation-induced DNA damage.

METHODS

Preirradiation biopsy samples of 64 patients with rectal carcinoma were analyzed. Genetic alterations of the p53 gene were detected by complete direct sequencing of exons 2 to 10. Expression of the nuclear phosphoprotein p53 was assessed by immunohistochemical staining. Results were correlated with histopathology of resected specimens and follow-up data, respectively.

RESULTS

Mutations of the p53 gene were present in 45% of tumors. Patients with a normal p53 gene had a significant survival advantage. Comparing pre- and postradiotherapy T category, a reduction was seen in patients with normal p53 genotype only. A mutant p53 genotype was highly specific in indicating stable disease concerning T category after irradiation. Protein overexpression was detected in 61%. Overexpression of the p53 protein was not related to survival or response. The concordance between immunohistochemistry and sequencing was only 0.51.

CONCLUSIONS

The authors show that downstaging after short-term radiation may occur but is seen in tumors with normal p53 gene only. Moreover, p53 genotype but not p53 immunohistochemistry is predictive for response to preoperative short-term radiotherapy and patient survival.

Role of radiation therapy in the treatment of resectable rectal adenocarcinoma

The purpose of this study is to review the role of radiation therapy in the treatment of resectable rectal adenocarcinoma. Selection criteria, treatment techniques, and results are discussed.

Complete response to neoadjuvant chemoradiation for rectal cancer does not influence survival

BACKGROUND

Up to 30% of patients with locally advanced rectal cancer have a complete clinical or pathologic response to neoadjuvant chemoradiation. This study analyzes complete clinical and pathologic responders among a large group of rectal cancer patients treated with neoadjuvant chemoradiation.

METHODS

From 1987 to 2000, 141 consecutive patients with biopsy-proven, locally advanced rectal cancer were treated with preoperative 5-fluorouracil-based chemotherapy and radiation. Clinical restaging after treatment consisted of proctoscopic examination and often computed tomography scan. One hundred forty patients then underwent operative resection, with results tracked in a database. Standard statistical methods were used to examine the outcomes of those patients with complete clinical or pathologic responses.

RESULTS

No demographic differences were detected between either clinical complete and clinical partial responders or pathologic complete and pathologic partial responders. The positive predictive value of clinical restaging was 60%, and accuracy was 82%. By use of the Kaplan-Meier life table analysis, clinical complete responders had no advantage in local recurrence, disease-free survival, or overall survival rates when compared with clinical partial responders. Pathologic complete responders also had no recurrence or survival advantage when compared with pathologic partial responders. Of the 34 pathologic T0 tumors, 4 (13%) had lymph node metastases.

CONCLUSIONS

Clinical assessment of complete response to neoadjuvant chemoradiation is unreliable. Micrometastatic disease persists in a proportion of patients despite pathologic complete response. Observation or local excision for patients thought to be complete responders should be undertaken with caution.

Neoadjuvant chemoradiation for rectal cancer: analysis of clinical outcomes from a 13-year institutional experience

OBJECTIVE

To examine clinical outcomes in patients receiving neoadjuvant chemoradiation for locally advanced rectal adenocarcinoma.

SUMMARY BACKGROUND DATA

Preoperative radiation therapy, either alone or in combination with 5-fluorouracil-based chemotherapy, has proven both safe and effective in the treatment of rectal cancer. However, data are lacking regarding which subgroups of patients benefit from the therapy in terms of decreased local recurrence and increased survival rates.

METHODS

A retrospective chart review was performed on 141 consecutive patients who received neoadjuvant chemoradiation (5-fluorouracil +/- cisplatin and 4,500-5,040 cGy) for biopsy-proven locally advanced adenocarcinoma of the rectum. Surgery was performed 4 to 8 weeks after completion of chemoradiation. Standard statistical methods were used to analyze recurrence and survival.

RESULTS

Median follow-up was 27 months, and mean age was 59 years (range 28-81). Mean tumor distance from the anal verge was 6 cm (range 1-15). Of those staged before surgery with endorectal ultrasound or magnetic resonance imaging, 57% of stage II patients and 82% of stage III patients were downstaged. The chemotherapeutic regimens were well tolerated, and resections were performed on 140 patients. The percentage of sphincter-sparing procedures increased from 20% before 1996 to 76% after 1996. On pathologic analysis, 24% of specimens were T0. However, postoperative pathologic T stage had no effect on either recurrence or survival. Positive lymph node status predicted increased local recurrence and decreased survival.

CONCLUSIONS

Neoadjuvant chemoradiation is safe, effective, and well tolerated. Postoperative lymph node status is the only independent predictor of recurrence and survival.

Management of locally advanced rectal cancer

The treatment of rectal cancer typically involves a multidisciplinary approach. A minority of patients will have tumors that are full thickness, involve adjacent structures, or have metastatic disease to regional lymph nodes. The combination of adjuvant therapy and surgical resection is the mainstay of treatment for locally advanced carcinoma of the rectum. This article will review the role of adjuvant chemotherapy and radiotherapy in patients with high risk tumors. The operative considerations in advanced rectal cancers will be reviewed. In particular, the role of mesorectal excision and exenterative surgery will be discussed.