Advanced Resectable Rectal Cancer Research Articles

A New Technique for Pelvic and Vaginal Reconstruction in Abdominoperineal Rectal Excision: Combination of Gluteus Maximus Flap and Fasciocutaneous Flap.

Resection of advanced rectal cancer might result in significant tissue loss, including pelvic floor and parts of the vaginal wall. Pelvic floor reconstruction using a musculocutaneous flap offers optimized healing abilities and the possibility of vaginal reconstruction. In Skåne University Hospital, two different flap techniques are used to reconstruct the perineum: the vertical rectus abdominis musculocutaneous flap and the gluteus maximus (GM) flap. A combination of a GM flap and a fasciocutanous flap, referred to locally as a GM special (GMS) flap, is used for posterior vaginal wall reconstruction in women undergoing abdominoperineal resections including parts of or the total posterior vaginal wall. The GMS flap was introduced through a national collaboration in Sweden in 2013. The aim of this article is to offer a detailed description and illustrations of the surgical technique used to construct the GMS flap, focusing on the posterior vaginal wall reconstruction. In our experience, the GMS flap is a resilient and cosmetically appealing choice that is technically easily harvested. The flap has acceptable morbidity and long-term results with adequate neovaginal measurements. Collaborative work is further encouraged.

Treatment response prediction of neoadjuvant chemotherapy for rectal cancer by deep learning of colonoscopy images.

In current clinical practice, several treatment methods, including neoadjuvant therapy, are being developed to improve overall survival or local recurrence rates for locally advanced rectal cancer. The response to neoadjuvant therapy is usually evaluated using imaging data collected before and after preoperative treatment or postsurgical pathological diagnosis. However, there is a need to accurately predict the response to preoperative treatment before treatment is administered. The present study used a deep learning network to examine colonoscopy images and construct a model to predict the response of rectal cancer to neoadjuvant chemotherapy. A total of 53 patients who underwent preoperative chemotherapy followed by radical resection for advanced rectal cancer at the Osaka University Hospital between January 2011 and August 2019 were retrospectively analyzed. A convolutional neural network model was constructed using 403 images from 43 patients as the learning set. The diagnostic accuracy of the deep learning model was evaluated using 84 images from 10 patients as the validation set. The model demonstrated a sensitivity, specificity, accuracy, positive predictive value and area under the curve of 77.6% (38/49), 62.9% (22/33), 71.4% (60/84), 74.5% (38/51) and 0.713, respectively, in predicting a poor response to neoadjuvant therapy. Overall, deep learning of colonoscopy images may contribute to an accurate prediction of the response of rectal cancer to neoadjuvant chemotherapy.

Cost-effectiveness analysis of long-course oxaliplatin and bolus of fluorouracil based preoperative chemoradiotherapy vs. 5x5Gy radiation plus FOLFOX4 for locally advanced resectable rectal cancer

PurposeTo evaluate the cost-effectiveness of preoperative short-course radiotherapy (SCRT, 5 × 5 Gy) plus FOLFOX4 versus long-course oxaliplatin and bolus of fluorouracil based preoperative long-course chemoradiotherapy (LCCRT, 50.4 Gy in 28 fractions) in the management of cT4 or advanced cT3 rectal cancer (RC), both of which have been reported to achieve similar clinical effect in the NCT00833131 trial.Materials and methodsA Markov decision-analytic model compared SCRT plus chemotherapy and LCCRT, by simulating three health states (disease-free survival (DFS), progressive disease (PD) and death). The primary outcomes were quality-adjusted life months (QALMs), costs, and incremental cost-effectiveness ratios (ICERs). Transition probabilities were based on the NCT00833131 trial. The costs were calculated from a Chinese payers’ perspective. Strategies were evaluated with a willingness-to-pay (WTP) threshold of $2370.47 (3 × GDP) per QALM gained. Sensitivity analysis was performed to model uncertainty in these parameters.ResultsThe overall costs for SCRT plus chemotherapy and LCCRT were $78,937 and $38,140 with effectiveness of 29.92 QALMs and 22.99 QALMs, respectively. SCRT plus chemotherapy increased costs and QALM by $40,797.34 and 6.93 compared to LCCRT, resulting in an ICER of $5884.56/QALM gained. In the DFS state, the whole cost for SCRT plus chemotherapy and LCCRT were $11,490.03 and $10,794.06 with an effectiveness of 21.70 QALMs and 19.65 QALMs, respectively. SCRT plus chemotherapy increased cost and QALM by $695.97 and 2.05 compared to LCCRT, resulting in a ICER of $339.50/QALM gained, which below the WTP. The utility associated with the DFS state was the most influential factor on the cost-effectiveness of SCRT plus chemotherapy. When the cost of PD state below $1920, the ICER of SCRT compared with LCCRT below the WTP.ConclusionCompared with LCCRT, SCRT plus chemotherapy is a more cost-effective strategy for locally advanced resectable RC in the DFS state as well as in the all states when the cost of PD state below $1920.

SPHINCTER PRESERVATION IN FOUR CONSECUTIVE PHASE II STUDIES OF PREOPERATIVE CHEMORADIATION: ANALYSIS OF 247 T3 RECTAL CANCER PATIENTS

To evaluate the impact of preoperative chemoradiation on sphincter preservation in patients with low-medium locally advanced resectable rectal cancer treated by four chemoradiation schedules. Between 1990 and 2002, 247 patients were treated according to four schedules of chemoradiotherapy: FUMIR (5-fluorouracil, mitomycin, external beam radiotherapy 37.8 Gy), PLAFUR (cisplatinum, 5-fluorouracil, external beam radiotherapy 50.4 Gy),TOMRT (raltitrexed, external beam radiotherapy 50.4 Gy), and TOMOXRT (raltitrexed, oxaliplatin, external beam radiotherapy 50.4 Gy). Four to five weeks after chemoradiation, patients were restaged and surgery was performed 2-3 weeks later. Overall, the sphincter-saving surgery was performed in 82.5% of patients. In patients candidate to an abdominoperineal resection before chemoradiaton (distance tumor-anorectal ring, < 30 mm) a sphincter-saving surgery was possible in 58% of cases: 44% (FUMIR), 52% (PLAFUR), 63% (TOMRT), 76% (TOMOXRT) (P < 0.017). The involved surgeons kept the same surgical criteria in performing sphincter-saving surgery. After chemoradiation, patients with tumor location still between 0 and 30 mm received sphincter-saving surgery according to the protocols: 33% (FUMIR), 42% (PLAFUR), 50% (TOMRT), 64% (TOMOXRT) (P = 0.066). Even though the surgeons' skill in performing sphincter-saving surgery could be improved with time, the high rate of this procedure in the latest schedules suggests an impact of the new drugs in promoting tumor downsizing and therefore sphincter-saving surgery.

Feasibility and preliminary effectiveness of a physical exercise training program during neoadjuvant chemoradiotherapy in individual patients with rectal cancer prior to major elective surgery

BackgroundDiverse fractions of patients with locally advanced resectable rectal cancer receive neoadjuvant chemoradiotherapy (NACRT). NACRT is known to decrease physical fitness, an undesirable side effect. This pilot aimed to determine the feasibility and preliminary effectiveness of a supervised outpatient physical exercise training program during NACRT in these patients. MethodsWe included 13 out of 20 eligible patients (11 males, mean ± SD age: 59.1 ± 19.7 years) with rectal cancer who participated in the exercise training program during NACRT. Feasibility was determined by adherence and number of adverse events. Physical fitness was compared at baseline (B), after five (T1) and ten weeks (T2) of training, and eight weeks postoperatively (T3) using repeated-measures analysis of variance. ResultsNine patients (69.2%) completed the program without adverse events. Four patients dropped out. The program was feasible and safe, with a total attendance rate of 95.7%. Leg muscle strength (mean ± SD: 104.0 ± 32.3 versus 144.8 ± 45.6 kg; P < 0.001) and arm muscle strength (mean ± SD: 48.7 ± 13.8 kg versus 36.1 ± 11.0 kg, P = 0.002) increased significantly between B and T2, respectively. A slight, non-significant, increase in functional exercise capacity was found. ConclusionThis pilot demonstrated that a supervised outpatient physical exercise training program for individual patients with locally advanced resectable rectal cancer during NACRT is feasible for a large part of the patients, safe and seems able to prevent an often seen decline in physical fitness during NACRT. A larger study into the cost-effectiveness of this approach is warranted.

PWE-332 A pilot randomised controlled trial using objective video assessment to investigate the impact of the interval between long-course chemoradiotherapy and resection of advanced rectal cancer upon technical performance of surgery

<h3>Introduction</h3> The optimal time to perform rectal cancer resection following long-course chemoradiotherapy (CRT) remains unclear. Many surgeons now elect to operate after a longer interval than the 6–8 weeks that was generally considered standard practice over the last decade. A longer interval may allow more precise surgery by allowing the radiation-induced inflammation to settle. The aim of this pilot multi-centre randomised controlled trial (RCT) was to evaluate the impact of the interval between CRT and surgery upon the technical complexity of the surgery. It was proposed that if a significant difference in complexity was found in this pilot study then progression to a large multi-centre RCT investigating the impact of the CRT-surgery interval upon rate of R0 resection would be indicated. <h3>Method</h3> Patients with rectal cancer requiring long-course CRT were recruited from seven centres between June 2012 and May 2014. Consenting patients were randomised to have surgery after an interval of either 6 weeks or 12 weeks following completion of long-course CRT. Expert interviews were used to generate a structured checklist describing the technical steps of the operation and a list of potential errors of the technical performance that may occur. Operations were video-recorded and unedited videos were analysed by a blinded research fellow against the structured checklist using an objective methodology to identify technical errors enacted. Additionally, the operating surgeons completed visual analogue scales to document their perception of the complexity of the procedure. Data were also collected on radiological downstaging, clinical outcomes to 30-days post-operation, quality of life, and pathological specimen completeness. <h3>Results</h3> Thirty one patients were enrolled into the study: 15 were randomised to a 6-week interval and 16 patients to 12-weeks. Four patients in the 6-week arm and two in the 12-week arm did not undergo surgery. Additionally, one patient in each arm was found to have unresectable disease at the time of surgery. Amongst the 23 patients who underwent resection there was no difference in frequency of errors identified per case between trial arms (p = 0.401), nor a difference in surgeon-reported complexity. No mortalities occurred. Other outcomes were similar between groups. <h3>Conclusion</h3> Objective video assessment of technical performance of surgery has been successfully used within the context of a pilot multi-centre RCT. The timing to surgery has no significant impact on error frequency between a 6-week or 12-week CRT-surgery interval. <h3>Disclosure of interest</h3> None Declared.

MiRNA-497 to enhance the sensitivity of colorectal cancer cells to neoadjuvant chemotherapeutic drug.

The neoadjuvant therapy has significantly improved the outcome of locally advanced resectable T3 rectal cancer patients. Actually, only a portion of patients show sensitivity to the preoperative chemoradiation and benefit markedly from this treatment. However, biomarkers for predicting neoadjuvant therapy sensitivity remain unclear. In this study, through screening of a series of microRNAs dysregulated in colorectal cancer patients, we observed that miRNA-497 expression was downregulated in tumor tissues of neoadjuvant chemotherapy responders as compared to that in non-responders. MiRNA-497 level was correlated with chemotherapeutic drug 5-fluorouracil (5-FU) sensitivity in colorectal cancer cells. Functional studies showed that restoration of miRNA-497 expression inhibited cell viability and enhanced 5-FU sensitivity in SW480 cells. By contrast, miRNA inhibitors-mediated silence of miRNA-497 promoted cell growth and reduced the sensitivity of LoVo cells to 5-FU. In addition, miRNA-497 targeted Smurf1 in CRC cells and the Smurf1 expression level was dramatically increased in neoadjuvant therapy-resistant patients compared with treatment-sensitive patients. These results indicate that down-regulation of miRNA-497 in colorectal cancer may contribute to the resistance of CRC cells to 5-FU treatment. Thus, miRNA-497 has the potential to be a novel biomarker for predicting the neoadjuvant chemotherapy sensitivity in CRC patients.

MiRNA-497 Enhances the Sensitivity of Colorectal Cancer Cells to Neoadjuvant Chemotherapeutic Drug.

The neoadjuvant therapy has significantly improved the outcome of locally advanced resectable T3 rectal cancer patients. Actually, only a portion of patients show sensitivity to the preoperative chemoradiation and benefit markedly from this treatment. However, biomarkers for predicting neoadjuvant therapy sensitivity remain unclear. In this study, through screening of a series of microRNAs dysregulated in colorectal cancer patients, we observed that miRNA-497 expression was downregulated in tumor tissues of neoadjuvant chemotherapy responders as compared to that in non-responders. MiRNA-497 level was correlated with chemotherapeutic drug 5-fluorouracil (5-FU) sensitivity in colorectal cancer cells. Functional studies showed that restoration of miRNA-497 expression inhibited cell viability and enhanced 5-FU sensitivity in SW480 cells. By contrast, miRNA inhibitors-mediated silence of miRNA-497 promoted cell growth and reduced the sensitivity of LoVo cells to 5-FU. In addition, miRNA-497 targeted Smurf1 in CRC cells and the Smurf1 expression level was dramatically increased in neoadjuvant therapy-resistant patients compared with treatment-sensitive patients. These results indicate that down-regulation of miRNA-497 in colorectal cancer may contribute to the resistance of CRC cells to 5-FU treatment. Thus, miRNA-497 has the potential to be a novel biomarker for predicting the neoadjuvant chemotherapy sensitivity in CRC patients.

Multivisceral resection for advanced rectal cancer: outcomes and experience at a single institution

BackgroundMultivisceral resection is often required in the treatment of locally advanced rectal cancers. Such resections are relatively rare and oncologic outcomes, especially when sphincter preservation is performed, are not fully demonstrated. MethodsA retrospective review was conducted of patients who underwent multivisceral resection for locally advanced rectal cancer with and without sphincter preservation. ResultsSixty-one patients underwent multivisceral resection for rectal cancer from 2005 to 2013 with a median follow-up of 27.8 months. Five-year overall and disease-free survival were 49.2% and 45.3%, respectively. Thirty-four patients (55.7%) had sphincter-sparing operations with primary coloanal anastomosis and temporary stoma. There was no significant difference in overall or disease-free survival, or recurrence with sphincter preservation compared with those with permanent stoma. ConclusionsMultivisceral resection for locally advanced rectal cancer has acceptable oncologic and clinical outcomes. Sphincter preservation and subsequent reestablishment of gastrointestinal continuity does not impact oncologic outcomes and should be considered in many patients.

Bleeding pseudoaneurysm of the internal iliac artery after extended resection for advanced rectal cancer: report of two cases

The incidence of locally advanced rectal cancer at diagnosis has increased despite surveillance programmes, especially among young patients [1]. Extended low anterior resection and pelvic exenteration after chemoradiotherapy have been described to be effective treatments for advanced primary or recurrent pelvic cancer although they are recognised to be technically demanding procedures associated with high morbidity and mortality rate [2]. Bleeding represents one of the most serious peri-operative complications, especially during pelvic exenteration. Secondary haemorrhage is much less common; to date, ruptured pseudoaneurysm of the pelvic arteries has not been described as a cause of massive postoperative rectal bleeding after surgery for advanced rectal cancer.

腹腔鏡下内肛門括約筋切除術後に下肢のAcute compartment syndromeをきたした進行下部直腸癌の1例

手術に関連するAcute compartment syndrome（ACS）は稀であり，早期の診断と加療が重要である．腹腔鏡下内肛門括約筋切除術後に下肢のACSをきたした症例を経験したので報告する．症例は進行下部直腸癌の40歳代男性．術前検査で側方リンパ節転移が疑われ，術前化学療法後に腹腔鏡下内肛門括約筋切除術および治療的両側側方リンパ節郭清術を施行した．体位は開脚頭低位を基本とし，会陰操作と側方リンパ節郭清時は頭低位かつ砕石位とした．手術時間は331分で出血は80mlであった．術後19時間に左下肢の激痛を認め，精査によりDVTは否定されACSの診断で発症後7時間に緊急減張切開術を施行した．primary sutureにより創部治癒し，その他の合併症を認めず術後13日で退院となった．術後14ヵ月現在，ACSの後遺症を認めず無再発経過観察中である．

Response to the Letter to the Editor Regarding the Manuscript Entitled “Positron Emission Tomography with [18F]-3′-Deoxy-3′Fluorothymidine (FLT) as a Predictor of Outcome in Patients with Locally Advanced Resectable Rectal Cancer: A Pilot Study”

Response to the Letter to the Editor Regarding the Manuscript Entitled “Positron Emission Tomography with [18F]-3′-Deoxy-3′Fluorothymidine (FLT) as a Predictor of Outcome in Patients with Locally Advanced Resectable Rectal Cancer: A Pilot Study”

Short-course preoperative radiotherapy combined with chemotherapy in resectable locally advanced rectal cancer: local control and quality of life

The authors sought to evaluate the clinical outcome after preoperative short-course radiotherapy (SC-RT) for locally advanced resectable rectal cancer in terms of local control (LC) and quality of life (QoL). Patients with locally advanced rectal cancer enrolled between 1997 and 2008 in an observational study of preoperative SC-RT were analysed. The treatment algorithm was neo-adjuvant chemotherapy (CT) administered for four cycles, followed by preoperative SC-RT administered 1 week after chemotherapy completion, delivering 20 Gy in five fractions over 1 week. Immediately in the following week surgery was performed. The adjuvant 5-FU-based CT was planned for pathological stage UICC≥II. LC, overall survival (OS), disease-free survival (DFS), early and late complications (RTOG scale) were analysed. All patients completed the EORTC QoL (C-30 and C-38), Faecal Incontinence QoL, and International Index of Erectile Function questionnaires (IIEF). A total of 67 patients were analysed. Chemotherapy and radiotherapy were well tolerated. At the pathological analysis, stable disease was obtained in 24 patients (36%), reduction of disease stage in 34 patients (50.7%), and progression in nine cases (13.3%). Adjuvant chemotherapy was indicated in 21 patients. Two locoregional recurrences, both within the radiotherapy volume, were observed, resulting in a 5-year LC of 97%. The 5-year DFS was 84%, with mean time to systemic progression of 24 months. After a mean follow-up of 114 months, the 5-year OS rate was 67%. Late toxicity >grade II was observed in 9% of patients. High anterior resection (AR) patients had significantly better scores than low AR or abdomino-perineal resection (APR). A total of 89% of the patients treated with conservative surgery had regular anal sphincter function. In male patients undergoing AR or APR, erectile dysfunction was found in 47% and 75% of the cases, respectively. Preoperative SC-RT combined with chemotherapy for locally advanced resectable rectal cancers was well tolerated. This treatment resulted in favourable LC, OS, low rates of toxicity and satisfying QoL.

Oxaliplatin‐related sinusoidal obstruction syndrome mimicking metastatic liver tumors

A 40-year-old woman who had undergone a curative low anterior resection for advanced rectal cancer was admitted to our hospital. She had been administrated oxaliplatin-based chemotherapy as postoperative adjuvant chemotherapy. The contrast-enhanced computed tomography revealed three hypovascular tumors, 3.0, 1.5 and 1.0 cm in diameter, located in the right hepatic lobe. The hepatocyte phase of the gadoxetic acid-enhanced magnetic resonance imaging demonstrated these lesions as hypointense tumors relative to the surrounding hepatic parenchyma. All these findings of the preoperative imaging modalities were compatible to metastatic liver tumors from the rectal cancer, and right hepatic lobectomy was successfully performed. Histopathologically, the tumors revealed sinusoidal dilation and severe congestion outlined by atrophic hepatocyte trabeculae, which was known as peliosis hepatis. The perisinusoidal space of Disse was extensively dilated and contained many erythrocytes. Taking these findings into account, the hepatic tumors were considered to be the space-occupying lesions resulting from the sinusoidal obstruction syndrome. We herein report the first case of focal sinusoidal obstruction syndrome mimicking metastatic liver tumors.

Letter to the Editor re: Positron Emission Tomography with [18F]-3′-Deoxy-3′fluorothymidine (FLT) as a Predictor of Outcome in Patients with Locally Advanced Resectable Rectal Cancer: a Pilot Study

Letter to the Editor re: Positron Emission Tomography with [18F]-3′-Deoxy-3′fluorothymidine (FLT) as a Predictor of Outcome in Patients with Locally Advanced Resectable Rectal Cancer: a Pilot Study

Long-term release of a malignant ileal obstruction by placement of a colorectal self-expandable metal stent.

An 84-year-old man underwent the Hartmann procedure with an R1 resection for advanced rectal cancer. One year after surgery, the patient presented with abdominal pain and vomiting. Abdominal radiography and computed tomography revealed an expanding small bowel and ileal obstruction caused by invasion of local, recurrent rectal cancer. In order to release the ileal obstruction, a colorectal self-expandable metal stent was placed via a through-the-scope technique using a colonoscope inserted through a stoma in the transverse colon. After stent placement, the patient's clinical symptoms and signs improved and the symptoms of obstruction did not recur. No major complications associated with the placement of the stent were observed during the 7-month follow-up period. Thus, self-expandable metal stents are a safe and effective palliative treatment for malignant gastroduodenal or colorectal obstructions, and as a bridge to surgery. However, endoscopic placement of these stents in cases of malignant small bowel obstruction is not yet feasible because of the limitations of endoscopic access and the stent delivery system. To our knowledge, this is the first report of malignant ileal obstruction treated with a colorectal self-expandable metal stent using a colonoscope. This case indicates that colorectal self-expandable metal stents can be effectively and safely used to treat malignant ileal obstructions.

Chemoradiotherapy followed by restorative proctocolectomy with partial intersphincteric resection for advanced rectal cancer associated with ulcerative colitis: report of a case

The role of restorative proctocolectomy with ileal J-pouch anal anastomosis (IPAA) is uncertain for patients with ulcerative colitis (UC), when advanced lower rectal cancer is diagnosed. We report what to our knowledge is the first documented case of successful preoperative chemoradiotherapy followed by IPAA with partial intersphincteric resection of advanced rectal cancer associated with UC. A 59-year-old woman with a 24-year history of extensive UC was found to have advanced rectal cancer located 2 cm from the anal verge. She underwent preoperative conventional chemoradiotherapy followed by restorative proctocolectomy with total mesorectal excision. The procedure included intersphincteric resection of one quadrant and construction of an IPAA with diverting ileostomy. The postoperative course was uneventful, and the ileostomy was closed 6 months after the initial surgery. The patient was doing well with good pouch function and no evidence of recurrent disease 1 year after her initial surgery.

607P - Efficacy and Safety of Two Neoadjuvant Strategies with Bevacizumab in Locally Advanced Resectable Rectal Cancer: Interim Results of a Randomized, Non-Comparative Phase II Study

ABSTRACT Background Current therapy of locally advanced resectable rectal cancer (LARC) involves a combination of chemotherapy (CT), radiation therapy, (RT) and total mesorectal excision (TME) surgery. Two neoadjuvant strategies with bevacizumab (Bv) were assessed in a randomized, open-label, multicentre, phase II study. Method Patients (pts) were treated with a sequential strategy including induction Bv/6 cycles (5mg/2weeks) + Folfox4, followed by CT-RT (Bv/6 cycles + 5-FU/5 cycles) + RT(45Gy) then TME in Arm A and the same CT-RT, then TME in Arm B. Primary end-point was tumor sterilization rate (pCR) - at least 10% in each arm. Efficacy and safety were reviewed by an independent committee. Results at 8 weeks post-surgery are presented. Results Pts characteristics in Arm A (n = 46) and in Arm B (n= 45) were: men 67%, age 60 ± 9 years, ECOG score 0 (85%), mid-rectum (60%), low-rectum (40%), MRI stage: T3N0M0/T3N1M0/T3N2M0 (20%/65%/15%). In Arm A, 94% pts completed induction and 91% had CT-RT and surgery; in Arm B 100% had CT-RT and 98% surgery. Resection was macroscopically complete in 91% pts. Median post-surgery hospitalization duration was 15 [0-84] days. In the ITT population, pCR (ypT0-N0) rate was 23.8% [12.1%-39.5%] in Arm A (p = 0.015) and 11.4% [3.8%-24.6%] in Arm B (p = 0.91), both compared to the 10% pCR initial hypothesis. Central review found similar results for pCR. At surgery and 4 weeks post-surgery grade 3/4 adverse events (AE) were reported in 10 (22%) of pts in both arms. At 8 weeks post-surgery, grade 3/4 adverse events (AE) were reported in 59% of pts in Arm A and 36% in Arm B. Grade 3/4 AEs of special interest for bevacizumab were reported in 20% of pts in Arm A and 22% in Arm B. No death was reported at 8 weeks post-surgery follow-up. Conclusions Interim results in patients with LARC treated with 2 neoadjuvant strategies showed that bevacizumab combination to neoadjuvant CT-RT did not significantly increase pCR in Arm B. The neoadjuvant strategy assessed in Arm A seems promising and deserves further investigation. Safety was comparable in Arms A and B at 8 weeks post-surgery. Disclosure T. Andre: Consultant: Roche Honoraries: Amgen, Merck, Sanofi. F. Boudghene: Honoraries : Roche. M. Piutti: Employment: Roche. All other authors have declared no conflicts of interest.

Positron Emission Tomography with [18F]-3′-Deoxy-3′fluorothymidine (FLT) as a Predictor of Outcome in Patients with Locally Advanced Resectable Rectal Cancer: a Pilot Study

This pilot study was performed to evaluate whether tumor uptake of (18)F-labeled 3'-deoxy-3'fluorothymidine (FLT), a proliferative radiotracer, at baseline and early during therapy, is predictive of outcome in locally advanced rectal cancer. Fourteen patients underwent positron emission tomography (PET) with 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) and FLT before therapy and PET with FLT approximately 2weeks after initiating neoadjuvant chemoradiotherapy. FLT and FDG uptake were evaluated qualitatively and by maximum standardized uptake value (SUV(max)). Tumor FLT and FDG uptake were correlated with disease-free survival (DFS). Thirteen patients underwent surgery after therapy, one died before surgery with progressive disease. FDG-PET/computed tomography detected regional lymph node metastases in five and FLT-PET was positive in one. High pretherapy FDG uptake (SUV(max) ≥ 14.3), low during-therapy FLT uptake (SUV(max) < 2.2), and high percentage change in FLT uptake (≥60%) were predictive of improved DFS (p < 0.05 for all three values). Pretherapy FDG uptake, during-therapy FLT uptake, and percentage change in FLT uptake were equally predictive of DFS.

Postoperative versus preoperative chemoradiotherapy in locally advanced rectal cancer patients.

e14156 Background: Postoperative chemo-radiotherapy is the recommended standard therapy for patients with locally advanced rectal cancer. In recent years, encouraging results with preoperative radiotherapy have been reported. We compared preoperative with postoperative chemo-radiotherapy for locally advanced rectal cancer patients. Methods: 84 patients with locally advanced resectable rectal cancer (clinical stage T3 or T4 or node-positive disease), 44 from them received neo- adjuvant radio-chemotherapy (Group I) before surgical resection versus 40 locally advanced rectal cancer patients received adjuvant radio-chemotherapy then chemotherapy after surgical resection (Group II). Statistical analysis of treatment response, duration of disease free, time to progression, survival rates, treatment tolerability and toxicity. Results: There is no statistically significant difference between rectal cancer patients as regard either survival function or disease recurrence. The overall three-year survival rates OS were 95.5 % (Group I) and 95 % (Group II), respectively (P=0.638). The disease free three-year survival rates DFS were 75% (Group I) and 70 % (Group II), respectively (P=0.908). The three-year cumulative incidence of local relapse was 25 percent for patients assigned to preoperative chemo-radiotherapy and 30 percent in the postoperative-treatment group (P=0.63). After preoperative chemo-radiotherapy, there is a significant shift toward earlier TNM stages (P=0.002) tumour with down staging. Conclusions: Preoperative as compared with post operative chemo-radiotherapy has a significant down staging given that it is associated with a superior overall compliance rate, an improved rate of local control, reduced toxicity, and an increased rate (66 %) of sphincter preservation in patients with low-lying tumours but did not improve survival rate.