Locally advanced rectal cancer: what is the evidence for induction chemoradiation?

A Nine-Gene Signature for Predicting the Response to Preoperative Chemoradiotherapy in Patients with Locally Advanced Rectal Cancer

Preoperative chemoradiotherapy (PCRT) and subsequent surgery is the standard multimodal treatment for locally advanced rectal cancer (LARC), albeit PCRT response varies among the individuals. This creates a dire necessity to identify a predictive model to forecast treatment response outcomes and identify patients who would benefit from PCRT. In this study, we performed a gene expression study using formalin-fixed paraffin-embedded (FFPE) tumor biopsy samples from 156 LARC patients (training cohort n = 60; validation cohort n = 96); we identified the nine-gene signature (FGFR3, GNA11, H3F3A, IL12A, IL1R1, IL2RB, NKD1, SGK2, and SPRY2) that distinctively differentiated responders from non-responders in the training cohort (accuracy = 86.9%, specificity = 84.8%, sensitivity = 81.5%) as well as in an independent validation cohort (accuracy = 81.0%, specificity = 79.4%, sensitivity = 82.3%). The signature was independent of all pathological and clinical features and was robust in predicting PCRT response. It is readily applicable to the clinical setting using FFPE samples and Food and Drug Administration (FDA) approved hardware and reagents. Predicting the response to PCRT may aid in tailored therapies for respective responders to PCRT and improve the oncologic outcomes for LARC patients.

Neoadjuvant volumetric modulated arc radiochemotherapy with a simultaneous integrated boost technique compared to standard chemoradiation for locally advanced rectal cancer

Background/aim

The present study aimed to examine whether the combination of neoadjuvant volumetric modulated arc radiotherapy (VMAT) using simultaneous integrated boost (SIB-VMAT) techniques and chemotherapy with capecitabine is associated with better clinical and dosimetric outcomes compared to the standard treatment.

Materials and methods

The study included 59 patients with cT2–T4 rectal cancer. In the standard arm, patients (n = 37) were treated preoperatively with image-guided VMAT plus capecitabine. In the SIB arm, patients (n = 22) were treated with the SIB-VMAT technique plus capecitabine. All patients underwent radical surgical resection after neoadjuvant radiochemotherapy.

Results

In the standard arm, cT0N0 was reached in 12 patients (32.4%), primary tumor clinical downstaging was observed in 22 patients (59.5%), and disease stability was achieved in 3 patients (8.1%). In the SIB arm, cT0N0 was reached in 15 patients (68.2%), primary tumor clinical downstaging was observed in 6 patients (27.3%), and disease stability was achieved in 1 patient (4.5%) (P = 0.028). Complete pathological response was observed in 11 patients (29.7%) in the standard arm and in 13 patients (59.1%) in the SIB arm (P = 0.026). In the SIB arm mild diarrhea appeared in 59.1%, moderate in 40.9%, and severe in 0% of the cases. In the standard arm mild, moderate, and severe diarrhea rates were in 54.1%, 43.2%, and 2.7%, respectively. In the SIB arm mild, moderate, and severe cystitis appeared in 63.6%, 22.7%, and 13.6%, while in the standard group mild cystitis developed in 67.6%, moderate in 24.3%, and severe in 8.1%. Mild, moderate, and severe radiation dermatitis rates were 45.5%, 45.5%, and 9.1% in the SIB group and 40.5%, 48.6%, and 10.8% in the standard group, respectively.

Conclusion

The SIB-VMAT technique is effective and safe for irradiating locally advanced rectal cancer. Its effectiveness is expressed in higher clinical and pathological complete response rates and safety with the same rates of acute toxicity.

Maintenance BEZ235 Treatment Prolongs the Therapeutic Effect of the Combination of BEZ235 and Radiotherapy for Colorectal Cancer

Our previous study demonstrated that administration of NVP-BEZ235 (BEZ235), a dual PI3K/mTOR inhibitor, before radiotherapy (RT) enhanced the radiotherapeutic effect in colorectal cancer (CRC) cells both in vitro and in vivo. Here, we evaluated whether maintenance BEZ235 treatment, after combinatorial BEZ235 + RT therapy, prolonged the antitumor effect in CRC. K-RAS mutant CRC cells (HCT116 and SW480), wild-type CRC cells (HT29), and HCT116 xenograft tumors were separated into the following six study groups: (1) untreated (control); (2) RT alone; (3) BEZ235 alone; (4) RT + BEZ235; (5) maintenance BEZ235 following RT + BEZ235 (RT + BEZ235 + mBEZ235); and (6) maintenance BEZ235 following BEZ235 (BEZ235 + mBEZ235). RT + BEZ235 + mBEZ235 treatment significantly inhibited cell viability and increased apoptosis in three CRC cell lines compared to the other five treatments in vitro. In the HCT116 xenograft tumor model, RT + BEZ235 + mBEZ235 treatment significantly reduced the tumor size when compared to the other five treatments. Furthermore, the expression of mTOR signaling molecules (p-rpS6 and p-eIF4E), DNA double-strand break (DSB) repair-related molecules (p-ATM and p-DNA-PKcs), and angiogenesis-related molecules (VEGF-A and HIF-1α) was significantly downregulated after RT + BEZ235 + mBEZ235 treatment both in vitro and in vivo when compared to the RT + BEZ235, RT, BEZ235, BEZ235 + mBEZ235, and control treatments. Cleaved caspase-3, cleaved poly (ADP-ribose) polymerase (PARP), 53BP1, and γ-H2AX expression in the HCT116 xenograft tissue and three CRC cell lines were significantly upregulated after RT + BEZ235 + mBEZ235 treatment. Maintenance BEZ235 treatment in CRC cells prolonged the inhibition of cell viability, enhancement of apoptosis, attenuation of mTOR signaling, impairment of the DNA-DSB repair mechanism, and downregulation of angiogenesis that occurred due to concurrent BEZ235 and RT treatment.

Kinetically guided neoadjuvant chemoradiotherapy based on 5-Fluorouracil in patients with locally advanced rectal cancer

BACKGROUND AND PURPOSE

This study estimated patients' early response following neoadjuvant chemoradiotherapy (CHRT) of locally advanced rectal cancer based on 5-fluorouracil (5-FU). The target was to achieve pathological complete response (pCR; residual disease-free stage) and toxicities of grade ≤2, using individual dosing predicted according to the steady-state plasma concentration (C ss) and pharmacokinetic parameters of 5-FU: the area under the time-concentration curve at steady state (AUC) and clearance (CL).

PATIENTS AND METHODS

This open-label prospective study enrolled 33 adult patients treated with 5-FU administered as a continuous intravenous infusion over 4-5 weeks, as follows: in Group 1a (N = 6), the patients received a standard dose of 300 mg/m(2)/24 h. In Group 1b (N = 7), the patients were treated with an escalated dose of 400-1,000 mg/m(2)/24 h. In Group 2 (N = 20), the patients were given dosing kinetically guided in order to reach the target range of 5-FU C ss 50-100 µg/L. Tolerability was tested according to Common Terminology Criteria for Adverse Events v3.0 (CTCAE). Radiotherapy was delivered with 10-15 MV photon beams at 1.8 Gy/fraction up to 50.4 Gy in 28 daily fractions for 5 days a week. Surgery followed 4-6 weeks after the completion of CHRT and clinical restaging. The pCR and residual tumour stage were evaluated using preoperative tumour downstaging in magnetic resonance, postoperative histopathological staging and tumour regression rate (residual disease).

RESULTS AND CONCLUSION

The cumulative AUC of 5-FU (total exposure to the drug) correlated with cumulative 5-FU dose (r = 0.61; p < 0.001) and residual disease (r s = -0.53; p < 0.005). A higher target pCR rate was reached in patients individually treated (Group 2) who finished the whole 5-week CHRT. The individual daily dose needed to reach the target C ss should be >350 mg/m(2) (up to 600 mg/m(2)) provided that 5-FU metabolic ratio is within the range of 2.5-6 and the cumulative AUC5wks is within 50-100 mg·h/L.

Dual phosphoinositide 3-kinase/mammalian target of rapamycin inhibitor is an effective radiosensitizer for colorectal cancer

The present study was aimed to investigate whether combination of molecular targeting therapy, a dual PI3K/mTOR inhibitor (BEZ235), with radiation can enhance the radiosensitivity of colorectal cancer cells (CRC). K-RAS mutant CRC cells (HCT 116 and SW 620) and wild type CRC cells (HT 29) were irradiated with different dose of radiation (0-6 Gy). The synergistic effects of combining radiation with different concentration of BEZ235 (0-10 nM) pretreatment were demonstrated by cell survival assay. When comparing with radiation alone and BEZ235 alone, the combination of BEZ235 pretreatment and radiation resulted in an increased percentage of sub-G1 phase cells, and an increased number of γ-H2AX/cell (DNA double strand breaks). Radiation up-regulated AKT/mTOR signaling pathway, including the activation of phospho (p)-AKT, p-mTOR, p-eIF4E, and p-rpS6; and this activated AKT/mTOR signaling pathway was attenuated by BEZ235 pretreatment. In addition, BEZ235 blocked double strand break repair induced by radiation through attenuating the activation of ATM and DNA-PKcs and sensitized CRC cells to radiation. In vivo model, the tumor size and the expression pattern of p-mTOR, p-eIF4E, and p-rpS6 were significantly decreased in combined group than radiation alone or BEZ235 alone. Our findings indicate that the administration of BEZ235 before radiation enhances the radiotherapeutic effect of CRC cells both in vitro and in vivo.

Neoadjuvant chemoradiation with concomitant boost radiotherapy associated to capecitabine in rectal cancer patients

PURPOSE

The primary end-points were complete pathological response and local control. Secondary end-points were survivals, anal sphincter preservation, and toxicity profile.

METHODS

Patients with T3/T4 and or N+ rectal cancer (n = 65) were treated with preoperative concomitant boost radiotherapy (55 Gy/25 fractions) associated to concurrent chemotherapy with oral capecitabine.

RESULTS

All patients completed the programmed treatment. The complete pathological response was achieved by 17 % of the patients. Anal sphincter preservation surgery was possible for 86 % of the patients with low rectal cancer (≤ 5 cm from the anal verge). The T-stage and N-stage downstaging were achieved by 40 and 58 % of the patients, respectively. Circumferential radial margin was involved (close/positive) in eight patients. After a median follow-up of 26 months, local and distant recurrence occurred in two and 11 patients, respectively. The 3-year overall survival and disease-free survival were 86.8 and 81 %, respectively. Non-hematological ≥ grade 3 toxicities were observed in 15 % of the patients. On univariate analysis N-downstaging and positive circumferential radial margin were significantly associated with worse overall survival (p = 0.003 and p = 0.023, respectively), disease-free survival (p = 0.001 and p = 0.036, respectively), and metastasis-free survival (MFS) (p = 0.001 and p = 0.038, respectively).On multivariate analysis, the N-downstaging were significantly associated with better overall survival (OS) (p = 0.022).

CONCLUSIONS

Our data support the efficacy of preoperative treatment for rectal cancer in terms of local outcomes. Radiation treatment intensification may have a biological rationale; longer follow-up is needed.

Microarray profiling of mononuclear peripheral blood cells identifies novel candidate genes related to chemoradiation response in rectal cancer

Preoperative chemoradiation significantly improves oncological outcome in locally advanced rectal cancer. However there is no effective method of predicting tumor response to chemoradiation in these patients. Peripheral blood mononuclear cells have emerged recently as pathology markers of cancer and other diseases, making possible their use as therapy predictors. Furthermore, the importance of the immune response in radiosensivity of solid organs led us to hypothesized that microarray gene expression profiling of peripheral blood mononuclear cells could identify patients with response to chemoradiation in rectal cancer. Thirty five 35 patients with locally advanced rectal cancer were recruited initially to perform the study. Peripheral blood samples were obtained before neaodjuvant treatment. RNA was extracted and purified to obtain cDNA and cRNA for hybridization of microarrays included in Human WG CodeLink bioarrays. Quantitative real time PCR was used to validate microarray experiment data. Results were correlated with pathological response, according to Mandard´s criteria and final UICC Stage (patients with tumor regression grade 1-2 and downstaging being defined as responders and patients with grade 3-5 and no downstaging as non-responders). Twenty seven out of 35 patients were finally included in the study. We performed a multiple t-test using Significance Analysis of Microarrays, to find those genes differing significantly in expression, between responders (n = 11) and non-responders (n = 16) to CRT. The differently expressed genes were: BC 035656.1, CIR, PRDM2, CAPG, FALZ, HLA-DPB2, NUPL2, and ZFP36. The measurement of FALZ (p = 0.029) gene expression level determined by qRT-PCR, showed statistically significant differences between the two groups. Gene expression profiling reveals novel genes in peripheral blood samples of mononuclear cells that could predict responders and non-responders to chemoradiation in patients with locally advanced rectal cancer. Moreover, our investigation added further evidence to the importance of mononuclear cells' mediated response in the neoadjuvant treatment of rectal cancer.

Combination of irinotecan and 5-fluorouracil with radiation in locally advanced rectal adenocarcinoma

OBJECTIVE

To evaluate toxicity and efficacy of addition of weekly irinotecan to a regimen of chemoradiotherapy of 5-fluorouracil with concurrent pelvic radiation in patients with locally advanced rectal cancer.

PATIENTS AND METHODS

Between October 2006 and December 2009, 36 patients with non-metastatic rectal adenocarcinoma were treated with chemoradiotherapy of irinotecan (50 mg/m(2) weekly), 5-fluorouracil (250 mg/m(2) for 5 days/week) and pelvic radiation (45 Gy/1.8 Gy/fraction for 5 days/week) by 3D conformal radiotherapy.

RESULTS

All patients completed the planned treatment. After the chemoradiotherapy, overall clinical response rate was 55.5% and pathological complete was 16.7%. Neutropenia was the most common hematologic toxicity (58.3%) with grade III in 5.5% while among non hematologic toxicity, diarrhea was the most common reported one (63.9%) with grade III in 13.9% followed by nausea and vomiting (47.2%). After a median follow-up of 23 months, progression-free and overall survival estimates at 2 years were 72% and 91.7%, respectively. Distant relapses were recoded in 16.7%, the main distant failure sites were lung and liver, and local relapse was found in 5.6%.

CONCLUSION

Combined chemoradiotherapy of irinotecan, 5-fluorouracil and radiotherapy for locally advanced non metastatic rectal adenocarcinoma is effective and safe. A prospective, randomized trial is needed to confirm these results in larger numbers and to compare this regimen with other non-irinotecan-based chemoradiotherapy regimens.

Is the standardized uptake value of FDG-PET/CT predictive of pathological complete response in locally advanced rectal cancer treated with capecitabine-based neoadjuvant chemoradiation?

OBJECTIVES

Our aim was to assess FDG-PET/CT as a surrogate biomarker of the pathological complete response in locally advanced rectal cancer treated with neoadjuvant chemoradiation.

METHODS

T3-4 and/or N+ rectal cancer patients were treated prospectively with capecitabine-based chemoradiation and total mesorectal excision 7-8 weeks later. FDG-PET/CT uptake was obtained at baseline, after 2 weeks, and 6 weeks following treatment completion, calculating the maximum standardized uptake value (SUV) and percentage difference to identify the early and late metabolic 'response index'.

RESULTS

Thirty-one patients were treated from January 2009 to January 2012 at the Istituto Nazionale dei Tumori of Milan. One patient was excluded due to surgery refusal. The pathological complete response rate was 30%. Early FDG-PET/CT was performed in 24 consenting patients and failed to show predictive utility. On the contrary, significant differences in late SUV value and response index were observed between complete and noncomplete pathological responders (p = 0.0006 and 0.03). In multivariate analysis including most relevant SUV parameters, none of them was independently associated with a pathological complete response. With receiver operating characteristic curve analysis, a late SUV threshold <5.4 had 81% sensitivity and 100% specificity, with 90% overall accuracy.

CONCLUSIONS

We evidenced a possible predictive role of late FDG-PET/CT for the assessment of pathological response in locally advanced rectal cancer following neoadjuvant chemoradiation.

Treatment of locally advanced rectal cancer: Controversies and questions

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

Multicenter phase II clinical trial of preoperative capecitabine with concurrent radiotherapy in patients with locally advanced rectal cancer

INTRODUCTION

To assess pathologic complete response, sphincter preservation rates and toxicity profile of preoperative chemoradiation with capecitabine in resectable locally advanced rectal cancer.

MATERIALS AND METHODS

Fifty-eight patients from six Spanish centers were included (March 2004 to June 2005) with histological/cytological diagnosis of locally advanced rectal cancer, age between 18 and 80 years, ECOG 0-2, adequate bone marrow, renal and hepatic functions. Prior chemotherapy/radiotherapy was not allowed. Preoperative treatment was capecitabine 825 mg/m(2) bid concomitant to radiotherapy (45 + 5.4 Gy boost over 5.5 weeks). Surgery was performed 4-8 weeks after completion of chemoradiotherapy.

RESULTS

Fifty-eight patients were enrolled in this study: 60.3 % males, median age of 64.5 (30.9-78.7) years, 28.6 % with ECOG 0 and 71.4 % with ECOG 1. Median distance of tumor from the anal verge was 7 (1-12) cm. Fifty-two (89.6. %) patients completed preoperative chemoradiotherapy. Primary tumor and node downstaging occurred in 61.1 and 69.6 % of patients, respectively. Surgery was performed in 55 patients (94.8 %): 80 % had negative lymph nodes and 72.7 % underwent sphincter-preserving procedures. A pathologic complete response was observed in 10.5 % (95 % CI 2.5-18.5) of the patients. Main grade I-II toxicities were leucopenia (43.1 %), neutropenia (24.1 %), anemia (36.2 %), diarrhea (32.8 %) and skin disorders (5.1 %), from which diarrhea (6.9 %), leucopenia (1.7 %) and skin disorders (1.7 %) reached grade III. There were no grade IV toxicities.

CONCLUSIONS

Preoperative capecitabine-based chemoradiation is a well-tolerated and effective neoadjuvant treatment for locally advanced rectal cancer that achieves encouraging rates of tumor downstaging.

Multicenter phase II clinical trial of preoperative capecitabine with concurrent radiotherapy in patients with locally advanced rectal cancer

INTRODUCTION

To assess pathologic complete response, sphincter preservation rates and toxicity profile of preoperative chemoradiation with capecitabine in resectable locally advanced rectal cancer.

MATERIALS AND METHODS

Fifty-eight patients from six Spanish centers were included (March 2004 to June 2005) with histological/cytological diagnosis of locally advanced rectal cancer, age between 18 and 80 years, ECOG 0-2, adequate bone marrow, renal and hepatic functions. Prior chemotherapy/radiotherapy was not allowed. Preoperative treatment was capecitabine 825 mg/m(2) bid concomitant to radiotherapy (45 + 5.4 Gy boost over 5.5 weeks). Surgery was performed 4-8 weeks after completion of chemoradiotherapy.

RESULTS

Fifty-eight patients were enrolled in this study: 60.3 % males, median age of 64.5 (30.9-78.7) years, 28.6 % with ECOG 0 and 71.4 % with ECOG 1. Median distance of tumor from the anal verge was 7 (1-12) cm. Fifty-two (89.6. %) patients completed preoperative chemoradiotherapy. Primary tumor and node downstaging occurred in 61.1 and 69.6 % of patients, respectively. Surgery was performed in 55 patients (94.8 %): 80 % had negative lymph nodes and 72.7 % underwent sphincter-preserving procedures. A pathologic complete response was observed in 10.5 % (95 % CI 2.5-18.5) of the patients. Main grade I-II toxicities were leucopenia (43.1 %), neutropenia (24.1 %), anemia (36.2 %), diarrhea (32.8 %) and skin disorders (5.1 %), from which diarrhea (6.9 %), leucopenia (1.7 %) and skin disorders (1.7 %) reached grade III. There were no grade IV toxicities.

CONCLUSIONS

Preoperative capecitabine-based chemoradiation is a well-tolerated and effective neoadjuvant treatment for locally advanced rectal cancer that achieves encouraging rates of tumor downstaging.

Locally advanced mid/low rectal cancer with synchronous liver metastases

BACKGROUND

Management of patients with T3/4 and/or N+ mid/low rectal cancer with synchronous liver metastases is not codified. The aim of this study was to analyze outcomes of our approach which consists of neoadjuvant chemotherapy or chemoradiotherapy, according to liver disease extension, followed by simultaneous rectal and liver resection.

METHODS

Between 2000 and 2009, 354 patients underwent hepatectomy for synchronous metastases. Thirty-six consecutive patients who underwent rectal and liver resection for metastatic T3/4 and/or N+ mid/low rectal cancer were analyzed.

RESULTS

Liver metastases were multiple in 27 patients, bilobar in 22, and >5 cm in six. Up-front treatment was chemotherapy in 15 patients, chemoradiotherapy in seven, chemotherapy followed by chemoradiotherapy in six, and surgery in eight (five symptomatic tumors). After chemotherapy alone (median number of cycles = 6), primary tumor response was observed in 11 patients (three complete responses). After chemoradiotherapy, only one patient had liver disease progression. Eighty-nine percent of patients underwent simultaneous rectal and hepatic resection. Mortality and morbidity rates were 2.8% (one pulmonary embolism) and 36%, respectively. After a mean follow-up of 39 months, 5-year overall and disease-free survival were 59.3 and 39.6%, respectively. Twenty-one patients had recurrence, including three pelvic recurrences (8.3%). No pelvic recurrence occurred among patients who correctly completed treatment strategy. All patients who received neoadjuvant chemoradiotherapy were alive and disease-free; 5-year overall and disease-free survival of patients receiving neoadjuvant chemotherapy were 59.3 and 25%, respectively.

CONCLUSIONS

For patients with metastatic T3/4 and/or N+ mid/low rectal cancer, the present strategy was safe and effective. Good disease control was achieved by neoadjuvant treatments, low morbidity rates were associated with simultaneous resection, and excellent long-term outcomes with low local relapse rate were obtained.

Preoperative treatment does not improve the therapeutic results of abdominosacral amputation of the rectum

BACKGROUND

This study reviewed the impact of preoperative chemoradiotherapy/short-term radiotherapy on abdominosacral amputations of the rectum (ASAR) for the treatment of low-rectum cancers in terms of postoperative morbidity, local recurrence rates, and survival.

METHODS

A total of 198 patients with stage II and III tumors located within 6 cm of the anorectal junction underwent ASAR between 1998 and 2008 and were selected for further analysis. Patients were compared according to the following groups: those who had surgery only (Group A) and those who had preoperative chemoradiotherapy/short-term radiotherapy (Group B).

RESULTS

There were 44 and 154 patients in Groups A and B, respectively, including 135 males. The median age of the subjects was 63 years (range = 35-88). The median follow-up period was 81 months (range = 23-138). Neither the local recurrence rates (6.8% in Group A vs. 4.6% in Group B, p = 0.544) nor the 5-year relative survival rates (72.4% in Group A vs. 69.3% in Group B, p = 0.127) differed significantly between the groups.

CONCLUSION

Preoperative therapy in low-rectum cancer does not improve the therapeutic results of ASAR.

Gender-specific acute organ toxicity during intensified preoperative radiochemotherapy for rectal cancer

Patients with locally advanced rectal cancer (cUICC stages II/III) are typically treated with preoperative 5-fluorouracil-based (5-FU-based) radiochemotherapy (RCT). However, trials are currently being conducted to improve the complete remission rates and the systemic control by combining 5-FU with oxaliplatin. The primary objective was to identify the subgroups of rectal cancer patients who were at risk for high-grade toxicity. All 196 patients who were included in the present study were treated with 50.4 Gy and chemotherapy that included either 5-FU (n = 115) or 5-FU+oxaliplatin (n = 81). The preoperative RCT was followed by a total mesorectal excision and adjuvant chemotherapy. Acute toxicity was monitored weekly and a toxicity grade ≥3 (Common Toxicity Criteria) for a skin reaction, cystitis, proctitis, or enteritis was defined as high-grade acute organ toxicity. After RCT with 5-FU+oxaliplatin, complete tumor remission was achieved in 13.6% of the patients and in 11.3% after RCT with 5-FU alone. Complete irradiation dosages of 50.4 Gy were given to 99% (5-FU) and 95% (5-FU+oxaliplatin) of the patients. Concomitant chemotherapy was fully administered in 95% of the patients treated with 5-FU compared with the 84% of patients treated with 5-FU+oxaliplatin. A significantly higher proportion of acute organ toxicity was found in the patients who were treated with 5-FU+oxaliplatin compared with those who were treated with 5-FU. Additionally, women with a low body mass index were at the highest risk for acute organ toxicity. These results suggest that there are basic clinical parameters, such as gender and body mass index, that may be potential markers for generating individual risk profiles of RCT-induced toxicity.

Stage-to-stage comparison of preoperative and postoperative chemoradiotherapy for T3 mid or distal rectal cancer

PURPOSE

To investigate, in a comparative analysis, the prognostic implications of postchemoradiotherapy (post-CRT) pathologic stage (ypStage) vs. postoperative pathologic stage (pStage) in rectal cancer.

METHODS AND MATERIALS

Between May 2001 and December 2006, 487 patients with T3 mid or distal rectal cancer were analyzed retrospectively. Concurrent CRT was administered preoperatively (n = 364, 74.7%) or postoperatively (n = 123, 25.3%). The radiation dose was 50.4 Gy in 28 fractions. All patients underwent a total mesorectal excision and received adjuvant chemotherapy. Disease-free survival (DFS) was estimated using the Kaplan-Meier method. Differences in DFS, stratified by ypStage and pStage, were compared using the log-rank test.

RESULTS

For surviving patients, the median follow-up period was 68 months (range, 12-105 months). The 5-year local recurrence-free survival rate was not different, at 95.3% and 92.1% in preoperative and postoperative CRT groups, respectively (p = 0.402), but the 5-year distant metastasis-free survival rate was significantly different, at 81.6% (preoperative CRT) vs. 65.4% (postoperative CRT; p = 0.001). The 5-year DFS rate of 78.8% in the preoperative CRT group was significantly better than the 63.0% rate in the postoperative CRT group (p = 0.002). Post-CRT pathologic Stage 0-I occurred in 42.6% (155 of 364) of the patients with preoperative CRT. The 5-year DFS rates were 90.2% (ypStage 0-I), 83.5% (ypStage II), 77.3% (pStage II), 58.6% (ypStage III), and 54.7% (pStage III). The DFS rate of ypStage 0-I was significantly better than that of ypStage II or pStage II. Post-CRT pathologic Stage II and III had similar DFS, compared with pStage II and III, respectively.

CONCLUSIONS

Disease-free survival predicted by each ypStage was similar to that predicted by the respective pStage. Improved DFS with preoperative vs. postoperative CRT was associated with the ypStage 0-I group that showed a similarly favorable outcome to pStage I rectal cancer.

Expression of hypoxia-inducible factor 1α predicts clinical outcome after preoperative hyperthermo-chemoradiotherapy for locally advanced rectal cancer

Hypoxia-inducible factor 1α (HIF-1α) is an intrinsic marker of tumor hypoxia. It has been considered that hypoxic conditions reduce radiosensitivity, but the role of HIF-1α in patients treated with preoperative therapy for rectal cancer is still unclear. The aim of this study was to evaluate the predictive value of tumor response to preoperative hyperthermo-chemoradiotherapy (HCRT) and the prognostic significance of HIF-1α expression in patients with locally advanced rectal cancer. Between 2003 and 2006, 50 patients with histologically proven rectal adenocarcinoma who underwent HCRT followed by surgery were investigated. HIF-1α expression was immunohistochemically evaluated using pre-treatment biopsies. The total radiation dose was 40-50 Gy and chemotherapy consisted of 5-FU and LV administered by continuous infusion on Day 1-5, Day 15-19, and Day 29-33 during radiotherapy. Hyperthermia treatment was performed for once a week for 2-5 sessions. The surgical operation was performed 8 weeks after HCRT and each resected specimen was graded by histological criteria of the Japanese Classification of Colorectal Carcinoma. The effects of HIF-1α on clinical outcomes were analyzed by univariate and multivariate analysis. Positive HIF-1α expression was recognized in 42.0% of samples (21/50). Resected specimens that showed pathological grades 1, 2, and 3 numbered 17, 24, and 9 cases, respectively. There were no significant differences between the HIF-1α-positive group and HIF-1α-negative group for pathological grading and pCR. Overall survival (OS) rate at 3 years in the HIF-1α-negative group was 85.2%, which was significantly better than the 60.6% in the HIF-1α-positive group. Recurrence-free survival (RFS) rate at 3 years in the HIF-1α-negative group was 82.8%, being significantly better than 47.6% in the HIF-1α-positive group. In addition, elevated HIF-1α expression was significantly correlated with recurrence-free survival and metastasis-free survival rate in multivariate analysis. HIF-1α expression might be predictive of recurrence-free survival and metastasis-free survival rate for rectal cancer patients treated with HCRT.

Complete clinical response to neoadjuvant chemoradiotherapy in patients with rectal cancer: opinions of British and Irish specialists

INTRODUCTION

Advances in neoadjuvant treatment have highlighted the phenomenon of complete clinical response (CCR) in a proportion of patients with rectal cancer. Radical surgery may be associated with a poor functional outcome and quality of life and has a small but significant risk of mortality. This study aimed to assess opinion of colorectal surgeons on issues surrounding the question of nonoperative management in patients who demonstrate complete response after neoadjuvant therapy.

METHOD

A questionnaire was sent to members of the Association of Coloproctology of Great Britain and Ireland regarding investigations, clinical management, pathological assessment and oncological outcome in rectal cancer patients with a complete response to neoadjuvant chemoradiotherapy.

RESULTS

A total of 122 consultants responded (26% response rate). Most surgeons (58%) would not consider conservative management of patients with a complete response and even more (69%) expressed that they would never discuss nonoperative management in patients with rectal cancer who are fit for curative surgery. Over 70 different combinations of investigations and imaging modalities were suggested to define a CCR. Eighty-six per cent of consultants felt that a pathology report stating no evidence of residual adenocarcinoma did not rule out the presence of tumour cells and all respondents estimated the percentage of patients with pathological complete response as < 20%.

CONCLUSIONS

No consensus exists as to what defines a complete response and at present there is resistance to offering nonoperative management in selected patients. With improvements in neoadjuvant treatment modalities, it will be increasingly important to consider nonoperative management in the future.

New specific molecular targets for radio-chemotherapy of rectal cancer

Patients with locally advanced rectal cancer often receive preoperative radio-chemotherapy (RCT). The mechanisms of tumour response to radiotherapy are not understood. The aim of this study was to identify the effects of RCT on gene expression in rectal tumour and normal rectal tissue. For that purpose tissue samples from 21 patients with resectable adenocarcinomas were collected for use in whole genome-microarray based gene expression analysis. A factorial experimental design allowed us to determine the effect of RCT on tumour tissue alone by removing the effect of radiation on normal tissue. This resulted in 1327 differentially expressed genes in tumour tissue with p<0.05. In addition to known markers for radio-chemotherapy, a Gene Set Enrichment Analysis (GSEA) showed a significant enrichment in gene sets associated with cell adhesion and leukocyte transendothelial migration. The profound change of cell adhesion molecule expression in rectal tumour tissue could either increase the risk of metastasis, or decrease the tumour's invasive potential.

Biomarkers for response to neoadjuvant chemoradiation for rectal cancer

Locally advanced rectal cancer (LARC) is currently treated with neoadjuvant chemoradiation. Although approximately 45% of patients respond to neoadjuvant therapy with T-level downstaging, there is no effective method of predicting which patients will respond. Molecular biomarkers have been investigated for their ability to predict outcome in LARC treated with neoadjuvant chemotherapy and radiation. A literature search using PubMed resulted in the initial assessment of 1,204 articles. Articles addressing the ability of a biomarker to predict outcome for LARC treated with neoadjuvant chemotherapy and radiation were included. Six biomarkers met the criteria for review: p53, epidermal growth factor receptor (EGFR), thymidylate synthase, Ki-67, p21, and bcl-2/bax. On the basis of composite data, p53 is unlikely to have utility as a predictor of response. Epidermal growth factor receptor has shown promise as a predictor when quantitatively evaluated in pretreatment biopsies or when EGFR polymorphisms are evaluated in germline DNA. Thymidylate synthase, when evaluated for polymorphisms in germline DNA, is promising as a predictive biomarker. Ki-67 and bcl-2 are not useful in predicting outcome. p21 needs to be further evaluated to determine its usefulness in predicting outcome. Bax requires more investigation to determine its usefulness. Epidermal growth factor receptor, thymidylate synthase, and p21 should be evaluated in larger prospective clinical trials for their ability to guide preoperative therapy choices in LARC.

Feasibility trial of partial breast irradiation with concurrent dose-dense doxorubicin and cyclophosphamide in early-stage breast cancer

PURPOSE

Anthracyclines and concurrent whole-breast irradiation result in prohibitive cutaneous toxicity. We hypothesized that anthracycline-based chemotherapy and concurrent partial breast irradiation (PBI) is safe and conducted a single-arm feasibility trial testing this hypothesis with dose-dense doxorubicin and cyclophosphamide (ddAC).

PATIENTS AND METHODS

Women with T1-2, N0-1 breast cancer with > or = 3 mm lumpectomy margins received PBI (40.5 Gy, 15 daily 2.7-Gy fractions) concurrently with the first two of four cycles of ddAC (60 and 600 mg/m2 of doxorubicin and cyclophosphamide, respectively, every 14 days with colony-stimulating support). Primary end points were local and systemic toxicity. Additional systemic therapy was given at the physician's discretion.

RESULTS

Twenty-seven patients enrolled between November 2004 and January 2007, but two patients did not receive protocol therapy (one found with additional local disease and one withdrew consent). Twenty-five women completed all planned PBI. Four (16%) of 25 did not complete all ddAC (febrile neutropenia [FN], n = 2; diverticulitis and neutropenia, n = 1; and social/economic reasons, n = 1). Four among the remaining 21 who completed all ddAC had a cycle delayed (FN, n = 1; acute respiratory illness, n = 1; foot blisters, n = 1; perianal dermatitis, n = 1). There was no grade 3 to 4 anemia or thrombocytopenia. Grade 3 nonhematologic toxicities (none grade 4) occurred in 28% (seven of 25) of patients (nausea/vomiting, n = 3; stomatitis, n = 2; contralateral breast abscess, n = 1; fatigue, n = 1; and cough/bronchospasms, n = 1). The observed rate of > or = grade 2 skin toxicity was 0% (0 of 25; one-sided 95% CI, 0% to 11%).

CONCLUSION

PBI with concurrent ddAC is feasible, and local/systemic toxicity is acceptable. Larger studies are warranted to assess long-term locoregional control and late toxicities.

Preoperative neo-adjuvant therapy for curable rectal cancer--reaching a consensus 2008

OBJECTIVE

Our aim was to determine the range of neo-adjuvant therapy the multidisciplinary team (MDT) currently offers patients with curable (M(0)) rectal cancer.

METHOD

A senior oncologist from each of the four oncology centres in north Wales and the north-west of England (approximate target population 8 million - Glan Clwyd, Clatterbridge, Christie and Preston) reviewed his/her understanding of the current evidence of neo-adjuvant therapy in rectal cancer. Then a representative from each centre was asked to identify which of three neo-adjuvant options (no neo-adjuvant therapy, short-course radiotherapy 25 Gy over five fractions and long-course chemoradiotherapy) he/she would use for a rectal cancer in the upper, middle or lower third of the rectum staged by magnetic resonance imaging as being T(2)-T(4) and/or N(0)-N(2).

RESULTS

In all cases of locally advanced rectal cancer (T(3a) N(1)-T(4)), oncologists from the four oncology centres recommended long-course chemoradiotherapy before rectal resection. This consensus was maintained for cases of lower third T(3a) N(0) cancers. Thereafter, the majority of patients with rectal cancer are offered adjuvant short-course radiotherapy.

CONCLUSION

Neo-adjuvant therapy is less likely to be offered if the tumour is early (T(2), N(0)) and/or situated in the upper third of the rectum.