Chemoradiotherapy and adjuvant chemotherapy for rectal cancer. Int J Clin Oncol. 2008;13:488-497. [PMID: 19093175 DOI: 10.1007/s10147-008-0849-0]

Cinnamaldehyde and Doxorubicin Co-Loaded Graphene Oxide Wrapped Mesoporous Silica Nanoparticles for Enhanced MCF-7 Cell Apoptosis

Background

Combined chemotherapy is often affected by the different physicochemical properties of chemotherapeutic drugs, which should be improved by the reasonable design of co-loaded preparations.

Purpose

A kind of simple but practical graphene oxide (GO) wrapped mesoporous silica nanoparticles (MSN) modified with hyaluronic acid (MSN@GO-HA) were developed for the co-delivery of cinnamaldehyde (CA) and doxorubicin (DOX), in order to enhance their combined treatment on tumor cells and reduce their application defects.

Methods

The MSN_CA@GO_DOX-HA was constructed by MSN_CA (loading CA via physical diffusion) and GO_DOX-HA (modified with HA and loading DOX via π–π stacking) through the electrostatic adsorption, followed by the physicochemical characterization, serum stability and in vitro release study. Cytotoxicity on different cells was detected, followed by the tumor cell uptake tests. The intracellular reactive oxygen species (ROS) changes, mitochondrial functions and activities of caspase-3/-9 in MCF-7 cells were also evaluated, respectively.

Results

The MSN_CA@GO_DOX-HA nanoparticles kept stable in FBS solution and achieved pH-responsive release behavior, which was beneficial to increase the accumulation of CA and DOX in tumor cells to enhance the treatment. MSN_CA@GO_DOX-HA exerted higher cytotoxicity to MCF-7 human breast cancer cells than H9c2 cardiac myocyte cells, which were not only attributed to the active targeting to tumor cells by HA, but also related with the activation of intrinsic apoptotic pathway in MCF-7 cells induced by CA, which was mediated by the specific ROS signal amplification and the interference with mitochondrial function. Moreover, the efficacy of DOX was also enhanced by the above process.

Conclusion

The establishment of the MSN_CA@GO_DOX-HA nanoparticles played a role in promoting strengths and restricting shortcomings of CA and DOX, thereby exerting their function and achieving efficient treatment against cancer.

Adjuvant chemotherapy in curatively resected rectal cancer: How valid are the data?

BACKGROUND

According to the result of the Cochrane review published in 2012, postoperative adjuvant chemotherapy (CTx) is associated with a survival benefit for rectal cancer patients operated for cure in comparison to patients who underwent only the surgical resection.

AIM

To analyze the quality of the data supporting the advantage of adjuvant CTx after surgery for rectal cancer. In the times of increasing health care costs, it is imperative to offer the patient an evidence-based therapy that justifies potential side effects as well as costs.

METHODS

Overall survival was selected as endpoint of interest. Among the 21 included papers which analyzed this endpoint, we identified those three publications which have the highest weights to influence the final result. The validity of these papers was analyzed using the CONSORT checklist for randomized controlled trials. We performed a second meta-analysis excluding the three analyzed studies (n = 18) in order to assess their impact on the overall result of the original meta-analysis. Finally, we performed a third meta-analysis excluding all studies (n = 16) which showed a statistically improved overall survival.

RESULTS

The detailed analysis of the three most relevant RCTs according to the items of the CONSORT checklist showed several pitfalls. In up to 47% of the items, inappropriate answers were found. Generally, a lack of information regarding the randomization procedure as well as the absence of allocation concealment, blinded set-up, of intention-to-treat analysis and omission of sample size calculation were common problems of the analyzed studies. The exclusion of these three studies from the meta-analysis did not affect the general result of the meta-analysis, still confirming a survival advantage after adjuvant chemotherapy. After exclusion of single studies with a statistically significant outcome improvement, the meta-analysis of the remaining 16 studies again shows a statistically significant result due in part to a large remaining sample size.

CONCLUSION

The three most powerful publications show substantial deficits. We suggest a more critical appraisal regarding the validity of single studies because a meta-analysis cannot overcome the limitations of individual trials by pooling treatment effect estimates to generate a single best estimate.

A New Prediction Model for Local Recurrence After Curative Rectal Cancer Surgery: Development and Validation as an Asian Collaborative Study

BACKGROUND

Local recurrence is one of the remaining problems in rectal and rectosigmoid cancer, and it is sometimes difficult to treat.

OBJECTIVE

This study aimed to explore various factors that are highly related to local recurrence and to develop a new prediction model for local recurrence after curative resection.

DESIGN

This is a retrospective cohort study SETTINGS:: This study was conducted at 2 academic hospitals in Japan and Korea.

PATIENTS

A total of 2237 patients with stage I to III rectal and rectosigmoid cancer who underwent a curative operation with a negative circumferential margin were selected.

INTERVENTIONS

Surgical treatment was the intervention.

MAIN OUTCOME MEASURES

Local recurrence was the primary outcome measure.

RESULTS

A total of 1232 patients were selected, and rectosigmoid cancer with rare local recurrence (2/221) was excluded. A different set of 792 patients with rectal cancer were chosen for validation. Multivariate analysis showed the following factors as significant for local recurrence: poorly differentiated tumor (HR, 11.2; 95% CI, 4.5-28.0), tumor depth (HR, 5.0), lymph node metastasis (HR, 4.1), operative procedure (HR, 3.2), postoperative complications (HR, 2.9), tumor location (HR, 2.6), and CEA level (HR, 2.4); a new prediction score was created by using these factors. A poorly differentiated tumor was assigned 2 points, and all other factors were assigned 1 point each. Patients who scored more than 5 points (n = 21) were judged as "high risk," with a 2-year local recurrence rate of 66.5%. The new predictive model could also separate the patients into different risk groups in the validation set. The high-risk group had higher recurrence rates than medium- and low-risk groups (2-year local recurrence rate: 41%, 15%, and 2.1%).

LIMITATIONS

This study was limited by its retrospective nature and potential for selection bias.

CONCLUSIONS

Seven factors were shown to be significantly correlated with the local recurrence of rectal cancer, and the usefulness of this new prediction model was demonstrated. See Video Abstract at http://links.lww.com/DCR/A429.

Is Chemotherapy or Radiation Therapy in Addition to Surgery Beneficial for Locally Advanced Rectal Cancer in the Elderly? A National Cancer Data Base (NCDB) Study

INTRODUCTION

Current National Comprehensive Cancer Network guidelines for Stages II and III rectal cancer recommend neoadjuvant chemoradiation followed by curative intent surgery and adjuvant chemotherapy. It is unclear whether therapies in addition to surgery are truly beneficial in elderly patients. Our aim was to compare the survival of patients over 80 with Stages II and III rectal cancer undergoing curative intent surgery with or without additional therapy.

MATERIALS AND METHODS

The National Cancer Data Base (NCDB 2006-2011) was queried for patients over 80 with Stages II and III rectal cancer. The primary outcome was overall survival. Patients were stratified based upon therapy group. Univariate group comparisons were made. Unadjusted Kaplan-Meier and multivariable Cox proportional hazards modeling survival analyses were performed.

RESULTS

The query yielded 3098 patients over 80 with Stage II (N = 1566) or Stage III (N = 1532) disease. Approximately, half of the patients received surgery only. Kaplan-Meier analysis showed improved survival for patients receiving neoadjuvant and/or adjuvant therapy in addition to surgery, but there was no significant difference between those that received guideline concordant care (GCC), neoadjuvant chemoradiation only, or post-operative chemotherapy only. Cox proportional hazard modeling identified age >90 and margin positivity as independent risk factors for decreased overall survival.

CONCLUSION

Analysis of NCDB data for Stages II and III rectal cancer in patients over 80 shows a survival benefit of adjuvant and/or neoadjuvant therapy over surgery alone. There does not appear to be a difference in survival between patients who received neoadjuvant chemoradiation, post-resection adjuvant chemotherapy, or GCC.

PIK3CA and PIK3CB silencing by RNAi reverse MDR and inhibit tumorigenic properties in human colorectal carcinoma

Colorectal carcinoma (CRC) is the second most common and frequent cause of cancer-related deaths for men and women in the world. PIK3CA and PIK3CB that reverse multidrug resistance (MDR) can serve as predictive and prognostic markers as well as therapeutic targets for CRC treatment. In the present study, we showed that PIK3CA and PIK3CB are upregulated in CRCs and positively correlated with MDR-1, LRP, and GST-π. Long-term monitoring of 316 CRC patients showed that PIK3CA and PIK3CB were associated with poor survival time as shown by Kaplan-Meier analysis. Furthermore, we found that the downregulation of PIK3CA and PIK3CB reversed MDR; inhibited the capability of proliferation, migration, and invasion of CRC cells; and slowed down the CRC tumor growth in nude mice. Consistent with clinical observations, PIK3CA and PIK3CB significantly increase multidrug resistance of CRC cells in vivo. Together, these results suggest that PIK3CA and PIK3CB may be used as potential therapeutic drug targets for colorectal cancer.

Complications associated with postoperative adjuvant radiation therapy for advanced rectal cancer

Preoperative management of advanced rectal cancer often includes chemoradiotherapy, but little is known about the late complications of radiotherapy. However, these are usually serious, making determination of the characteristics of late complications after radiation therapy critical. Accordingly, we investigated the complications occurring after adjuvant pelvic radiation therapy in patients with advanced rectal cancer. We enrolled 34 consecutive patients with TNM stage III rectal cancer who had undergone curative surgery with adjuvant pelvic radiation therapy. Data on the type of complication/organ involved, the number of complications, the phase of onset, and the treatments used were reviewed. Patients who experienced gut complications or edema were less likely to have their complications resolved than those with complications due to infection. Similarly, patients with multiple complications and late-onset complications were also less likely to have their complications resolved than those with single complications and those with early-onset complications, respectively. Adjuvant radiation therapy in patients with resected advanced rectal cancer was associated with various complications, characterized by late onset and impaired resolution. Therefore, patients indicated for radiation therapy should be selected with great caution.

Clinical significance of LGR5 and CD44 expression in locally advanced rectal cancer after preoperative chemoradiotherapy

LGR5, known as a target of Wnt signaling, has been reported as an intestinal stem cell marker. Recent reports showed that LGR5 was associated with carcinogenesis and tumor invasion in colorectal cancer. CD44 is a ubiquitously expressed cell adhesion molecule and also a potential cell surface marker on colon cancer stem cells. Both LGR5 and CD44 have been also reported to be Wnt signal targets. The aim of this study was to investigate the association of these markers with clinical outcome in rectal cancer after preoperative chemoradiotherapy (CRT). A total of 52 rectal cancer specimens were obtained from patients who underwent preoperative CRT. We performed transcriptional and immunohistochemical analyses, and retrospectively studied the association of LGR5 and CD44 expression levels with clinical outcomes. For CD44, its expression in cancer stroma was also evaluated. The levels of cancer LGR5 and CD44 gene expression were significantly and positively correlated. LGR5 gene expression level in cancer and positivity of CD44 gene expression in cancer stroma were significantly correlated with disease recurrence. Elevated cancer LGR5 gene expression and positive CD44 gene expression in cancer stroma were significantly associated with poor recurrence-free and overall survival. Multivariate analysis indicated that positivity of stromal CD44 gene expression was an independent prognostic factor for the recurrence and overall survival of patients with rectal cancer after preoperative CRT. In conclusion, LGR5 and CD44 expression may be coordinately associated with tumor relapse in locally advanced rectal cancer after preoperative CRT.

Locally metastatic mucinous rectal adenocarcinoma: Imaging diagnosis with DW-MRI in comparison with PET-CT

A 56-year-old male patient with locally advanced mucinous rectal cancer underwent neoadjuvant chemoradiotherapy. Follow-up imaging with positron emission tomography-computed tomography (PET-CT) revealed a local response to chemoradiotherapy, whereas diffusion-weighted magnetic resonance imaging (DW-MRI) showed newly presented sacral bone metastasis. Histopathologically confirmed bone metastasis and the local tumor were surgically removed. Repeat DW-MRI revealed tumor recurrence in the sacral excision zone eight months after surgery, which was reconfirmed by histopathology. This case shows the superior imaging ability of DW-MRI in the diagnosis of mucinous tumors in comparison to PET-CT.

Assessment of response to chemoradiation therapy in rectal cancer using MR volumetry based on diffusion-weighted data sets: a preliminary report

PURPOSE

This study evaluated the feasibility of magnetic resonance (MR) volumetry using a diffusion-weighted data set (V(DWI)) and compared it with conventional T2-weighted volumetry (V(C)) in patients affected by rectal cancer treated with chemoradiation therapy (CHRT).

MATERIALS AND METHODS

Fourteen patients with a biopsy diagnosis of rectal cancer underwent MR examination before and after CHRT. T2-weighted images were used to extrapolate V(C). A diffusion-weighted (DW) sequence was acquired [spin-echo diffusion-weighted echo-planar imaging (SE-DW-EPI)] with a b-value of 800 s/mm(2) and volume (V(DWI)) was calculated by semiautomatic segmentation of tumour hyperintensity. Two radiologists independently assessed volumes and analysed data in order to establish interobserver agreement and compare and correlate volumes to tumour regression grade (TRG), as evaluable at pathological examination of the surgical specimen.

RESULTS

Interobserver agreement was 0.977 [(95% confidence interval (CI) 0.954-0.989) and 0.956 (95% CI 0.905-0.980) for V(C) and V(DWI) and 0.964 (95% CI 0.896-0.988) and 0.271 (95% CI-0.267 to 0.686) between V(C) and V(DWI) before and after CHRT. The correlation between TRG and V(C) and V(DWI) was, respectively, rho = 0.597 (p<0.05) and r(2)=0.156 (p=0.162) and rho=0.847 (p<0.001).

CONCLUSIONS

V(DWI) seems to be a promising tool for assessing response to CHRT in rectal cancer. Further studies on large series of patients are needed to refine the technique and evaluate its potential predictive value.

Postoperative adjuvant chemotherapy in rectal cancer operated for cure

BACKGROUND

Colorectal cancer is one of the most common types of cancer in the Western world. Apart from surgery - which remains the mainstay of treatment for resectable primary tumours - postoperative (i.e., adjuvant) chemotherapy with 5-fluorouracil (5-FU) based regimens is now the standard treatment in Dukes' C (TNM stage III) colon tumours i.e. tumours with metastases in the regional lymph nodes but no distant metastases. In contrast, the evidence for recommendations of adjuvant therapy in rectal cancer is sparse. In Europe it is generally acknowledged that locally advanced rectal tumours receive preoperative (i.e., neoadjuvant) downstaging by radiotherapy (or chemoradiotion), whereas in the US postoperative chemoradiotion is considered the treatment of choice in all Dukes' C rectal cancers. Overall, no universal consensus exists on the adjuvant treatment of surgically resectable rectal carcinoma; moreover, no formal systematic review and meta-analysis has been so far performed on this subject.

OBJECTIVES

We undertook a systematic review of the scientific literature from 1975 until March 2011 in order to quantitatively summarize the available evidence regarding the impact of postoperative adjuvant chemotherapy on the survival of patients with surgically resectable rectal cancer. The outcomes of interest were overall survival (OS) and disease-free survival (DFS).

SEARCH METHODS

CCCG standard search strategy in defined databases with the following supplementary search. 1. Rect* or colorect* - 2. Cancer or carcinom* or adenocarc* or neoplasm* or tumour - 3. Adjuv* - 4. Chemother* - 5. Postoper*

SELECTION CRITERIA

Randomised controlled trials (RCT) comparing patients undergoing surgery for rectal cancer who received no adjuvant chemotherapy with those receiving any postoperative chemotherapy regimen.

DATA COLLECTION AND ANALYSIS

Two authors extracted data and a third author performed an independent search for verification. The main outcome measure was the hazard ratio (HR) between the risk of event between the treatment arm (adjuvant chemotherapy) and the control arm (no adjuvant chemotherapy). The survival data were either entered directly in RevMan or extrapolated from Kaplan-Meier plots and then entered in RevMan. Due to expected clinical heterogeneity a random effects model was used for creating the pooled estimates of treatment efficacy.

MAIN RESULTS

A total of 21 eligible RCTs were identified and used for meta-analysis purposes. Overall, 16,215 patients with colorectal cancer were enrolled, 9,785 being affected with rectal carcinoma. Considering patients with rectal cancer only, 4,854 cases were randomized to receive potentially curative surgery of the primary tumour plus adjuvant chemotherapy and 4,367 to receive surgery plus observation. The mean number of patients enrolled was 466 (range: 54-1,243 cases). 11 RCTs had been performed in Western countries and 10 in Japan. All trials used fluoropyrimidine-based chemotherapy (no modern drugs - such as oxaliplatin, irinotecan or biological agents - were tested).Overall survival (OS) data were available in 21 RCTs and the data available for meta-analysis regarded 9,221 patients: of these, 4854 patients were randomized to adjuvant chemotherapy (treatment arm) and 4,367 patients did not receive adjuvant chemotherapy (control arm). The meta-analysis of these RCTs showed a significant reduction in the risk of death (17%) among patients undergoing postoperative chemotherapy as compared to those undergoing observation (HR=0.83, CI: 0.76-0.91). Between-study heterogeneity was moderate (I-squared=30%) but significant (P=0.09) at the 10% alpha level.Disease-free survival (DFS) data were reported in 20 RCTs, and the data suitable for meta-analysis included 8,530 patients. Of these, 4,515 patients were randomized to postoperative chemotherapy (treatment arm) and 4,015 patients received no postoperative chemotherapy (control arm). The meta-analysis of these RCTs showed a reduction in the risk of disease recurrence (25%) among patients undergoing adjuvant chemotherapy as compared to those undergoing observation (HR=0.75, CI: 0.68-0.83). Between-study heterogeneity was moderate (I-squared=41%) but significant (P=0.03).While analyzing both OS and DFS data, sensitivity analyses did not find any difference in treatment effect based on trial sample size or geographical region (Western vs Japanese). Available data were insufficient to investigate on the effect of adjuvant chemotherapy separately in different TNM stages in terms of both OS and DFS. No plausible source of heterogeneity was formally identified, although variability in treatment regimens and TNM stages of enrolled patients might have played a significant role in the difference of reported results.

AUTHORS' CONCLUSIONS

The results of this meta-analysis support the use of 5-FU based postoperative adjuvant chemotherapy for patients undergoing apparently radical surgery for non-metastatic rectal carcinoma. Available data do not allow us to define whether the efficacy of this treatment is highest in one specific TNM stage. The implementation of modern anti-cancer agents in the adjuvant setting is warranted to improve the results shown by this meta-analysis. Randomized trials of adjuvant chemotherapy for patients receiving preoperative neoadjuvant therapy are also needed in order to define the role of postoperative chemotherapy in the multimodal treatment of resectable rectal cancer.

Postoperative adjuvant chemotherapy in rectal cancer operated for cure

BACKGROUND

Colorectal cancer is one of the most common types of cancer in the Western world. Apart from surgery - which remains the mainstay of treatment for resectable primary tumours - postoperative (i.e., adjuvant) chemotherapy with 5-fluorouracil (5-FU) based regimens is now the standard treatment in Dukes' C (TNM stage III) colon tumours i.e. tumours with metastases in the regional lymph nodes but no distant metastases. In contrast, the evidence for recommendations of adjuvant therapy in rectal cancer is sparse. In Europe it is generally acknowledged that locally advanced rectal tumours receive preoperative (i.e., neoadjuvant) downstaging by radiotherapy (or chemoradiotion), whereas in the US postoperative chemoradiotion is considered the treatment of choice in all Dukes' C rectal cancers. Overall, no universal consensus exists on the adjuvant treatment of surgically resectable rectal carcinoma; moreover, no formal systematic review and meta-analysis has been so far performed on this subject.

OBJECTIVES

We undertook a systematic review of the scientific literature from 1975 until March 2011 in order to quantitatively summarize the available evidence regarding the impact of postoperative adjuvant chemotherapy on the survival of patients with surgically resectable rectal cancer. The outcomes of interest were overall survival (OS) and disease-free survival (DFS).

SEARCH METHODS

CCCG standard search strategy in defined databases with the following supplementary search. 1. Rect* or colorect* - 2. Cancer or carcinom* or adenocarc* or neoplasm* or tumour - 3. Adjuv* - 4. Chemother* - 5. Postoper*

SELECTION CRITERIA

Randomised controlled trials (RCT) comparing patients undergoing surgery for rectal cancer who received no adjuvant chemotherapy with those receiving any postoperative chemotherapy regimen.

DATA COLLECTION AND ANALYSIS

Two authors extracted data and a third author performed an independent search for verification. The main outcome measure was the hazard ratio (HR) between the risk of event between the treatment arm (adjuvant chemotherapy) and the control arm (no adjuvant chemotherapy). The survival data were either entered directly in RevMan or extrapolated from Kaplan-Meier plots and then entered in RevMan. Due to expected clinical heterogeneity a random effects model was used for creating the pooled estimates of treatment efficacy.

MAIN RESULTS

A total of 21 eligible RCTs were identified and used for meta-analysis purposes. Overall, 16,215 patients with colorectal cancer were enrolled, 9,785 being affected with rectal carcinoma. Considering patients with rectal cancer only, 4,854 cases were randomized to receive potentially curative surgery of the primary tumour plus adjuvant chemotherapy and 4,367 to receive surgery plus observation. The mean number of patients enrolled was 466 (range: 54-1,243 cases). 11 RCTs had been performed in Western countries and 10 in Japan. All trials used fluoropyrimidine-based chemotherapy (no modern drugs - such as oxaliplatin, irinotecan or biological agents - were tested).Overall survival (OS) data were available in 21 RCTs and the data available for meta-analysis regarded 9,221 patients: of these, 4854 patients were randomized to adjuvant chemotherapy (treatment arm) and 4,367 patients did not receive adjuvant chemotherapy (control arm). The meta-analysis of these RCTs showed a significant reduction in the risk of death (17%) among patients undergoing postoperative chemotherapy as compared to those undergoing observation (HR=0.83, CI: 0.76-0.91). Between-study heterogeneity was moderate (I-squared=30%) but significant (P=0.09) at the 10% alpha level.Disease-free survival (DFS) data were reported in 20 RCTs, and the data suitable for meta-analysis included 8,530 patients. Of these, 4,515 patients were randomized to postoperative chemotherapy (treatment arm) and 4,015 patients received no postoperative chemotherapy (control arm). The meta-analysis of these RCTs showed a reduction in the risk of disease recurrence (25%) among patients undergoing adjuvant chemotherapy as compared to those undergoing observation (HR=0.75, CI: 0.68-0.83). Between-study heterogeneity was moderate (I-squared=41%) but significant (P=0.03).While analyzing both OS and DFS data, sensitivity analyses did not find any difference in treatment effect based on trial sample size or geographical region (Western vs Japanese). Available data were insufficient to investigate on the effect of adjuvant chemotherapy separately in different TNM stages in terms of both OS and DFS. No plausible source of heterogeneity was formally identified, although variability in treatment regimens and TNM stages of enrolled patients might have played a significant role in the difference of reported results.

AUTHORS' CONCLUSIONS

The results of this meta-analysis support the use of 5-FU based postoperative adjuvant chemotherapy for patients undergoing apparently radical surgery for non-metastatic rectal carcinoma. Available data do not allow us to define whether the efficacy of this treatment is highest in one specific TNM stage. The implementation of modern anti-cancer agents in the adjuvant setting is warranted to improve the results shown by this meta-analysis. Randomized trials of adjuvant chemotherapy for patients receiving preoperative neoadjuvant therapy are also needed in order to define the role of postoperative chemotherapy in the multimodal treatment of resectable rectal cancer.

A phase II study of oxaliplatin with 5-FU/folinic acid and concomitant radiotherapy as a preoperative treatment in patients with locally advanced rectal cancer

OBJECTIVE

To evaluate the activity and safety of adding oxaliplatin to a standard chemoradiotherapy schema, including 5-fluorouracil (5-FU)/folinic acid (FA), in locally-advanced rectal cancer (LARC).

METHODS

Two cycles of oxaliplatin 130 mg/m(2) plus FA 20 mg/m(2) bolus for 5 days and 5-FU 350 mg/m(2) continuous infusion for 5 days were given during week 1 and 4 of pelvic radiotherapy 46 Gy. Patients with a T3/4 and/or node-positive rectal tumour were eligible. Surgery was performed 4-6 weeks after radiotherapy. The primary endpoint was to determine the rate of pathological response. Secondary endpoints were to assess the rate of clinical response and the safety profile.

RESULTS

Between March 2005 and January 2009, a total of 35 patients were enrolled. The pathological down-staging rate was 79% with a pathological complete response rate of 17%. The overall clinical response rate (assessed by computed tomography or transrectal ultrasound) was 77%. Grade 3 diarrhoea and Grade 3 neutropaenia were reported in 14% and 11% of the patients, respectively. Eleven patients did not undergo surgery: four of them refused the operation, and seven patients were inoperable due to disease progression. In 24 patients who had surgery, a sphincter-preserving procedure could be performed in 29%. At the median follow-up time of 28.1 months, 25 patients (71%) survived with no evidence of disease.

CONCLUSION

The promising results in terms of pathological response, and the associated good safety profile of a regimen of oxaliplatin plus 5-FU/FA with concomitant radiotherapy, suggest that the regimen could be used in LARC.

Accuracy of endoscopic ultrasound to assess tumor response after neoadjuvant treatment in rectal cancer: can we trust the findings?

BACKGROUND

The finding that some rectal cancers respond to neoadjuvant chemoradiation is broadening new surgical options for the treatment of some of these tumors that, until now, required a total mesorectal excision. Nevertheless, a fine match between clinical and pathological response is required when planning conservative surgical approaches.

OBJECTIVE

This study aims to prospectively validate the use of endoscopic ultrasound as a predictor of clinical and pathological tumor response in patients with locally advanced rectal cancer.

DESIGN

: This is an observational study of a cohort of patients undergoing chemoradiation followed by surgery.

SETTINGS

This study was conducted at a tertiary medical center.

PATIENTS

A total of 235 consecutive patients who underwent chemoradiation followed by surgery at a single institution during a 7-year period were included.

MAIN OUTCOME MEASURES

All tumors were staged and restaged at 4 to 6 weeks after neoadjuvant treatment. Downsizing and downstaging were calculated between the initial and posttreatment measures and correlated to the pathological stage. The accuracy of endoscopic ultrasound to predict response was determined.

RESULTS

Findings after chemoradiation showed T-downstaging in 54 patients (23%) and N-downstaging in 110 (47%). Overstaging occurred in 88 (37%) patients and was more commonly observed than understaging (21 patients; 9%). Related to the pathological report, endoscopic ultrasound correctly matched the T stage in 54% and the N stage in 75% of tumors. Sensitivity, specificity, and positive and negative predictive values to predict nodal involvement were 39%, 91%, 67%, and 76%. Accuracy was not influenced by such factors as age, distance of the tumor from the anal verge, or time to surgery.

LIMITATIONS

This study was limited by the lack of comparison with other imaging methods.

CONCLUSIONS

Endoscopic ultrasound allows prediction of involved lymph nodes in 75% of the cases; however, 1 in 5 patients are missclassified as uN0 after neoadjuvant treatment. In our point of view, this percentage is too high to rely only on this diagnostic modality to support a "wait and see" approach.

Neoadjuvant therapy for rectal cancer: the impact of longer interval between chemoradiation and surgery

PURPOSE

The aim of this study was to determine the effect of a longer interval between neoadjuvant chemoradiation and surgery on perioperative morbidity and oncologic outcomes.

METHODS

A colorectal cancer database was queried for clinical stage II and III rectal cancer patients undergoing neoadjuvant chemoradiation followed by proctectomy between 1997 and 2007. The neoadjuvant regimen consisted of long course external beam radiation and 5-fluorouracil chemotherapy. Patients with inflammatory bowel disease, hereditary cancer, extracolonic malignancy, urgent surgery, or non-validated treatment dates were excluded. Patients were divided into two groups according to the interval between chemoradiation and surgery (<8 and ≥ 8 weeks). Perioperative complications and oncologic outcomes were compared.

RESULTS

One hundred seventy-seven patients were included. Groups were comparable with respect to demographics, tumor, and treatment characteristics. Perioperative complications were not affected by the interval between chemoradiation and surgery. Patients undergoing surgery ≥ 8 weeks after chemoradiation experienced a significant improvement in pathologic complete response rate (30.8% vs. 16.5%, p = 0.03) and had decreased 3-year local recurrence rate (1.2% vs. 10.5%, p = 0.04). A Cox regression analysis was performed to assess the compounding effect of a complete pathologic response on oncologic outcome. A longer interval correlated with less local recurrence, although statistical significance was not reached (p = 0.07).

CONCLUSION

An interval between chemoradiation and surgery ≥ 8 weeks is safe and is associated with a higher rate of pathologic complete response and decreased local recurrence.

Pathologic complete response after neoadjuvant treatment for rectal cancer decreases distant recurrence and could eradicate local recurrence

BACKGROUND

The aim of this study was to evaluate the clinical implications of pathologic complete response (pCR) (i.e., T0N0M0) after neoadjuvant chemoradiation and radical surgery in patients with locally advanced rectal cancer.

MATERIALS AND METHODS

A single-center, prospectively maintained colorectal cancer database was queried for patients with primary cII and cIII rectal cancer staged by CT and ERUS/MRI undergoing long-course neoadjuvant chemoradiation followed by proctectomy with curative intent between 1997 and 2007. Patients were stratified into pCR and no-pCR groups and compared with respect to demographics, tumor and treatment characteristics, and oncologic outcomes. Outcomes evaluated were 5-year overall survival, disease-free survival, disease-specific mortality, local recurrence, and distant recurrence.

RESULTS

The query returned 238 patients (73% male), with a median age of 57 years and median follow-up of 54 months. Of these, 58 patients achieved pCR. Patients with pCR vs no-pCR were statistically comparable with respect to demographics, chemoradiation regimens, tumor distance from anal verge, clinical stage, surgical procedures performed, and follow-up time. No patient with pCR had local recurrence. Overall survival and distant recurrence were also significantly improved for patients achieving pCR.

CONCLUSIONS

Achievement of pCR after neoadjuvant chemoradiation is associated with greatly improved cancer outcomes in locally advanced rectal cancer. Future studies should evaluate the relationship between increases in pCR rates and improvements in cancer outcomes in this population.

Local excision following pre-operative chemoradiotherapy-induced downstaging for selected cT3 distal rectal cancer

OBJECTIVE

To investigate the long-term outcomes of selected patients with cT3 distal rectal cancer treated with local excision following pre-operative chemoradiotherapy.

METHODS

Between January 2003 and February 2008, 11 patients with cT3 distal rectal cancer received a local excision following pre-operative chemoradiotherapy. The median age of the patients was 61 years (range, 42-71). The median tumor size was 3 cm (range, 2-5), and the median distance of the caudal tumor edge from the anal verge was 3 cm (range, 1-4). Clinical lymph node status was positive in five patients. Pre-operative chemoradiotherapy consisted of a 50.4 Gy in 28 fractions with concurrent chemotherapy. A transanal full-thickness local excision was performed after a median of 54 days (range, 31-90) from chemoradiotherapy completion. Ten patients received post-operative chemotherapy.

RESULTS

Pathologically complete responses occurred in eight patients, ypT1 in two and ypT2 in one. The pathologic tumor size for three ypT1-2 tumors was 0.9, 1.1 and 2.2 cm. The follow-up period was a median of 59 months (range, 24-85). One patient (ypT0) developed recurrence at the excision site 14 months after surgery, but was successfully salvaged with an abdominoperineal resection and adjuvant chemotherapy. Another patient (ypT2) developed bone metastasis after 8 months and died of the disease. The 5-year local recurrence-free, disease-free and overall survival rates were 90.9%, 81.8% and 88.9%, respectively. No Grade 3 or worse gastrointestinal toxicity was detected.

CONCLUSIONS

Full-thickness local excision following chemoradiotherapy may be an acceptable option for cT3 distal rectal cancer that responds well to chemoradiotherapy.

Impact of neoadjuvant treatment on total mesorectal excision for ultra-low rectal cancers

Background

This study reviewed the impact of pre-operative chemoradiotherapy or post-operative chemotherapy and/or radiotherapy on total mesorectal excision (TME) for ultralow rectal cancers that required either low anterior resection with peranal coloanal anastomosis or abdomino-perineal resection (APR). We examined surgical complications, local recurrence and survival.

Methods

Of the 1270 patients who underwent radical resection for rectal cancer from 1994 till 2007, 180 with tumors within 4 cm with either peranal coloanal anastomosis or APR were analyzed. Patients were compared in groups that had surgery only (Group A), pre-operative chemoradiotherapy (Group B), and post-operative therapy (Group C).

Results

There were 115 males and the mean age was 65.43 years (range 30-89). APR was performed in 134 patients while 46 had a sphincter-preserving resection with peranal coloanal anastomosis. The mean follow-up period was 52.98 months (range: 0.57 to 178.9). There were 69, 58 and 53 patients in Groups A, B, and C, respectively. Nine patients in Group B could go on to have sphincter-saving rectal resection. The overall peri-operative complication rate was 43.4% in Group A vs. 29.3% in Group B vs. 39.6% in Group C, respectively. The local recurrence rate was significantly lower in Group B (8.6.9% vs. 21.7% in Group A vs. 33.9% in Group C) p < 0.05. The 5-year cancer-specific survival rates for Group A was 49.3%, Group B was 69.9% and Group C was 38.8% (p = 0.14).

Conclusion

Pre-operative chemoradiation in low rectal cancer is not associated with a higher incidence of peri-operative complications and its benefits may include reduction local recurrence.

Ex vivo sentinel lymph node mapping in patients undergoing proctectomy for rectal cancer

PURPOSE

Controversy exists over the utility of sentinel lymph node mapping in the treatment of rectal cancer. The purpose of this study was to evaluate the use of ex vivo sentinel lymph node mapping in the setting of proctectomy for rectal cancer, with and without multilevel sectioning and immunohistochemistry.

METHODS

A prospective phase 2 clinical study of subjects undergoing proctectomy for rectal cancer from 2003 to 2008 was conducted. Sentinel lymph node mapping was performed with ex vivo injection of isosulfan blue. Sentinel lymph nodes were examined by hematoxylin and eosin evaluation, and when the results were negative, they were examined by multilevel sectioning and immunohistochemistry.

RESULTS

The study population consisted of 58 subjects; 88% received neoadjuvant therapy. Tumors were downstaged in 25 (49%) subjects receiving neoadjuvant therapy, 24% were clinical complete responders, and 20% were pathologic complete responders. The mean total lymph node harvest was 12.1 nodes per patient. Twenty-five subjects had positive nodal disease on final pathology. The sentinel lymph node detection rate was 85%, with a mean sentinel lymph node harvest of 2.2 nodes per subject. Fifteen (26%) subjects had sentinel lymph node nodal metastasis on routine hematoxylin and eosin examination. Neither multilevel sectioning nor immunohistochemistry evaluation improved detection of sentinel lymph node positivity. The accuracy of sentinel lymph node mapping was 71%, the sensitivity was 53%, the negative predictive value was 79%, and the false negative rate was 47%. Seven subjects were determined to have nodal disease only in the sentinel lymph node.

CONCLUSION

Ex vivo sentinel lymph node mapping is feasible after proctectomy for rectal cancer but did not improve staging. Neither multilevel sectioning nor immunohistochemistry improved the sensitivity of sentinel lymph node mapping.

Downstaging without complete pathologic response after neoadjuvant treatment improves cancer outcomes for cIII but not cII rectal cancers

BACKGROUND

The aim of this study was to evaluate whether downstaging impacts prognosis in patients with cII versus cIII rectal cancer.

MATERIALS AND METHODS

We identified from our colorectal cancer database 295 patients with primary cII and cIII rectal cancer staged by CT and ERUS/MRI who received 5-FU-based chemoradiation followed by R0 surgery after a median interval of 7 weeks during 1997-2007. The median radiotherapy dose was 5040 cGy. We excluded 58 patients with pathologic complete response (pCR) and compared among the remaining 162 patients pathologic downstaging (cII to ypI, cIII to ypII or ypI) versus no pathologic downstaging (c stage < or = yp stage). Outcomes evaluated were 5-year overall survival, 3-year cancer-specific survival, disease-free survival, overall recurrence, local recurrence, and distant recurrence.

RESULTS

The median age was 58 years and median follow-up was 48 months. Patients with downstaging versus no downstaging were statistically comparable with respect to demographics, chemoradiation regimen, interval time between neoadjuvant chemoradiation and surgery, tumor distance from anal verge, surgical procedures performed, and follow-up time. With the exception of local recurrence rates, downstaging resulted in significantly improved cancer outcomes for cIII but not cII.

CONCLUSIONS

Downstaging without pCR is a significant prognostic factor for patients with stage cIII rectal cancer. Tumor response to neoadjuvant chemoradiation should be taken into account when defining the optimal adjuvant chemotherapy regimen for patients with cIII rectal cancer.