Maria Antonietta Gambacorta

Prognostic value of pathologic complete response after neoadjuvant therapy in locally advanced rectal cancer: long-term analysis of 566 ypCR patients.

PURPOSE In the literature, a favorable prognosis was observed for complete pathologic response after preoperative therapy (ypCR) in patients with locally advanced rectal cancer. The aim of this study is to verify whether ypCR predicts a favorable outcome in a large series of patients. METHODS AND MATERIALS The Gastro-Intestinal Working Group of the Italian Association of Radiation Oncology collected clinical data for 566 patients with ypCR (ypT0N0) after neoadjuvant therapy. Eligibility criteria included locally advanced rectal cancer with no evidence of metastases at the time of diagnosis, evidence of ypCR after preoperative radiotherapy +/- chemotherapy (CT). RESULTS Median radiation dose was 50 Gy. A total of 527 patients (93%) received one of 12 different neoadjuvant CT schedules. Sphincter preservation, anteroposterior resection, and endoscopic surgery were performed in 73%, 22%, and 5% of patients, respectively. Adjuvant CT was administered to 22% of patients. Median follow-up was 46.4 months. Locoregional recurrence occurred in 7 patients (1.6%). Distant metastases occurred in 49 patients (8.9%). Overall, 5-year rates of disease-free survival, overall survival, and cancer-specific survival were 85%, 90%, and 94%, respectively. In multivariate analysis, only age and clinical stage statistically correlated with survival outcome. Adjuvant CT was still of borderline significance (worse for adjuvant CT). No relation was found between survival and neoadjuvant CT schedules. CONCLUSION A ypCR after neoadjuvant therapy identified a favorable group of patients, even in this large series of 566 patients collected in 61 centers. Locoregional recurrence occurred only in 1.6% patients.

Nomograms for Predicting Local Recurrence, Distant Metastases, and Overall Survival for Patients With Locally Advanced Rectal Cancer on the Basis of European Randomized Clinical Trials

PURPOSE The purpose of this study was to develop accurate models and nomograms to predict local recurrence, distant metastases, and survival for patients with locally advanced rectal cancer treated with long-course chemoradiotherapy (CRT) followed by surgery and to allow for a selection of patients who may benefit most from postoperative adjuvant chemotherapy and close follow-up. PATIENTS AND METHODS All data (N = 2,795) from five major European clinical trials for rectal cancer were pooled and used to perform an extensive survival analysis and to develop multivariate nomograms based on Cox regression. Data from one trial was used as an external validation set. The variables used in the analysis were sex, age, clinical tumor stage stage, tumor location, radiotherapy dose, concurrent and adjuvant chemotherapy, surgery procedure, and pTNM stage. Model performance was evaluated by the concordance index (c-index). Risk group stratification was proposed for the nomograms. RESULTS The nomograms are able to predict events with a c-index for external validation of local recurrence (LR; 0.68), distant metastases (DM; 0.73), and overall survival (OS; 0.70). Pathologic staging is essential for accurate prediction of long-term outcome. Both preoperative CRT and adjuvant chemotherapy have an added value when predicting LR, DM, and OS rates. The stratification in risk groups allows significant distinction between Kaplan-Meier curves for outcome. CONCLUSION The easy-to-use nomograms can predict LR, DM, and OS over a 5-year period after surgery. They may be used as decision support tools in future trials by using the three defined risk groups to select patients for postoperative chemotherapy and close follow-up (http://www.predictcancer.org).

Locally advanced rectal cancer: MR imaging in prediction of response after preoperative chemotherapy and radiation therapy.

PURPOSE To prospectively differentiate, at magnetic resonance (MR) imaging, patients with locally advanced nonmucinous rectal cancer who will respond to long-course chemotherapy and radiation therapy (CRT) from those who will not respond, with histopathologic results as the reference standard. MATERIALS AND METHODS Institutional review board approval for this study was obtained, and all patients provided written informed consent. High-spatial-resolution T2-weighted MR images were acquired before and 6-8 weeks after CRT in 53 patients (33 men, 20 women; mean age, 63 years; age range, 42-79 years). Patients were categorized as responders to CRT (patients with T3 cancer that converted to T2 or a lower stage, patients with T4 cancer that converted to T3 or a lower stage) or as nonresponders (patients with stable or progressive disease). At the posttreatment MR imaging examination, a decrease in signal intensity was considered to represent a morphologic response with fibrosis. Before CRT and surgery, tumor volume was calculated at MR imaging by multiplying cross-sectional area by section thickness. Tumor length was measured at MR imaging and in the histopathologic specimen. Nodal downstaging was evaluated. The relationship between pathologic response, morphologic MR imaging response, and percentage volume reduction was evaluated with the Mann-Whitney-Wilcoxon two-sample test. RESULTS Morphologic response assessment with MR imaging achieved a positive predictive value (PPV) of 84.2% (32 of 38) and a negative predictive value (NPV) of 66.7% (10 of 15). Volume reduction extent (> or = 70%) was significantly different between patients in whom disease was downstaged and those in whom it was not downstaged (P = .000005) and showed additional diagnostic value, with an overall accuracy of 86.8% (46 of 53). Presurgical MR imaging and histopathologic tumor length did not show a significant difference. MR imaging accuracy for lymph node (N) stage was 86.8% (46 of 53) on the basis of morphologic criteria. CONCLUSION After CRT, morphologic and volumetric evaluation at MR imaging had a high PPV and a low NPV for response assessment. The detection of small clusters of residual tumor cells within fibrosis remains a problem. SUPPLEMENTAL MATERIAL http://radiology.rsnajnls.org/cgi/content/full/250/3/730/DC1.

EURECCA colorectal: Multidisciplinary management: European consensus conference colon & rectum

BACKGROUND Care for patients with colon and rectal cancer has improved in the last 20years; however considerable variation still exists in cancer management and outcome between European countries. Large variation is also apparent between national guidelines and patterns of cancer care in Europe. Therefore, EURECCA, which is the acronym of European Registration of Cancer Care, is aiming at defining core treatment strategies and developing a European audit structure in order to improve the quality of care for all patients with colon and rectal cancer. In December 2012, the first multidisciplinary consensus conference about cancer of the colon and rectum was held. The expert panel consisted of representatives of European scientific organisations involved in cancer care of patients with colon and rectal cancer and representatives of national colorectal registries. METHODS The expert panel had delegates of the European Society of Surgical Oncology (ESSO), European Society for Radiotherapy & Oncology (ESTRO), European Society of Pathology (ESP), European Society for Medical Oncology (ESMO), European Society of Radiology (ESR), European Society of Coloproctology (ESCP), European CanCer Organisation (ECCO), European Oncology Nursing Society (EONS) and the European Colorectal Cancer Patient Organisation (EuropaColon), as well as delegates from national registries or audits. Consensus was achieved using the Delphi method. For the Delphi process, multidisciplinary experts were invited to comment and vote three web-based online voting rounds and to lecture on the subjects during the meeting (13th-15th December 2012). The sentences in the consensus document were available during the meeting and a televoting round during the conference by all participants was performed. This manuscript covers all sentences of the consensus document with the result of the voting. The consensus document represents sections on diagnostics, pathology, surgery, medical oncology, radiotherapy, and follow-up where applicable for treatment of colon cancer, rectal cancer and metastatic colorectal disease separately. Moreover, evidence based algorithms for diagnostics and treatment were composed which were also submitted to the Delphi process. RESULTS The total number of the voted sentences was 465. All chapters were voted on by at least 75% of the experts. Of the 465 sentences, 84% achieved large consensus, 6% achieved moderate consensus, and 7% resulted in minimum consensus. Only 3% was disagreed by more than 50% of the members. CONCLUSIONS Multidisciplinary consensus on key diagnostic and treatment issues for colon and rectal cancer management using the Delphi method was successful. This consensus document embodies the expertise of professionals from all disciplines involved in the care for patients with colon and rectal cancer. Diagnostic and treatment algorithms were developed to implement the current evidence and to define core treatment guidance for multidisciplinary team management of colon and rectal cancer throughout Europe.

Local excision after preoperative chemoradiotherapy for rectal cancer: results of a multicenter phase II clinical trial.

BACKGROUND: Transanal local excision has been suggested as an attractive approach for patients with rectal cancer who show a major clinical response after preoperative chemoradiotherapy. OBJECTIVE: To evaluate the impact of transanal local excision on the local recurrence of rectal cancer in patients who had a major clinical response after preoperative chemoradiotherapy. DESIGN: Sequential 2-stage phase II study for early efficacy. SETTING: Multicenter study. PATIENTS: Patients with clinical T3 or low-lying T2 rectal adenocarcinoma that showed a major clinical response after a preoperative chemoradiotherapy. Eligible patients underwent a full-thickness transanal local excision. According to their histopathology, the patients staged as ypT0-1 were observed, while the remaining patients were recommended to undergo a subsequent total mesorectal excision. MAIN OUTCOME MEASURES: A local recurrence rate of ⩽5% was set as a successful rate for stopping the trial early after the first stage. RESULTS: The study group included 63 patients. Before chemoradiotherapy, patients were staged as clinical T3 (n = 42) and T2 (n = 21). After the local excision, 43 patients fulfilled the criteria to be observed with no further treatment. Nine of the remaining 20 patients for whom a subsequent total mesorectal excision was recommended refused surgery. Two of these patients who refused surgery had intraluminal local recurrence; both had a ypT2 tumor and underwent salvage surgery. The estimated cumulative 3-year overall survival, disease-free survival and local disease-free survival were 91.5% (95% CI: 75.9–97.2), 91.0% (95% CI: 77.0–96.6) and 96.9% (95% CI: 80.3–99.5), respectively. LIMITATIONS: The time of follow-up is still short and the sample size is limited. CONCLUSIONS: Our data suggest that local excision is a good option for patients with a major clinical response after chemoradiotherapy. A longer period of follow-up is required to confirm these findings.

Development and external validation of a predictive model for pathological complete response of rectal cancer patients including sequential PET-CT imaging

PURPOSE To develop and validate an accurate predictive model and a nomogram for pathologic complete response (pCR) after chemoradiotherapy (CRT) for rectal cancer based on clinical and sequential PET-CT data. Accurate prediction could enable more individualised surgical approaches, including less extensive resection or even a wait-and-see policy. METHODS AND MATERIALS Population based databases from 953 patients were collected from four different institutes and divided into three groups: clinical factors (training: 677 patients, validation: 85 patients), pre-CRT PET-CT (training: 114 patients, validation: 37 patients) and post-CRT PET-CT (training: 107 patients, validation: 55 patients). A pCR was defined as ypT0N0 reported by pathology after surgery. The data were analysed using a linear multivariate classification model (support vector machine), and the models performance was evaluated using the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. RESULTS The occurrence rate of pCR in the datasets was between 15% and 31%. The model based on clinical variables (AUC(train)=0.61±0.03, AUC(validation)=0.69±0.08) resulted in the following predictors: cT- and cN-stage and tumour length. Addition of pre-CRT PET data did not result in a significantly higher performance (AUC(train)=0.68±0.08, AUC(validation)=0.68±0.10) and revealed maximal radioactive isotope uptake (SUV(max)) and tumour location as extra predictors. The best model achieved was based on the addition of post-CRT PET-data (AUC(train)=0.83±0.05, AUC(validation)=0.86±0.05) and included the following predictors: tumour length, post-CRT SUV(max) and relative change of SUV(max). This model performed significantly better than the clinical model (p(train)<0.001, p(validation)=0.056). CONCLUSIONS The model and the nomogram developed based on clinical and sequential PET-CT data can accurately predict pCR, and can be used as a decision support tool for surgery after prospective validation.

Diffusion-Weighted Magnetic Resonance Imaging in Monitoring Rectal Cancer Response to Neoadjuvant Chemoradiotherapy

PURPOSE To prospectively monitor the response in patients with locally advanced nonmucinous rectal cancer after chemoradiotherapy (CRT) using diffusion-weighted magnetic resonance imaging. The histopathologic finding was the reference standard. METHODS AND MATERIALS The institutional review board approved the present study. A total of 62 patients (43 men and 19 women; mean age, 64 years; range, 28-83) provided informed consent. T(2)- and diffusion-weighted magnetic resonance imaging scans (b value, 0 and 1,000 mm(2)/s) were acquired before, during (mean 12 days), and 6-8 weeks after CRT. We compared the median apparent diffusion coefficients (ADCs) between responders and nonresponders and examined the associations with the Mandard tumor regression grade (TRG). The postoperative nodal status (ypN) was evaluated. The Mann-Whitney/Wilcoxon two-sample test was used to evaluate the relationships among the pretherapy ADCs, extramural vascular invasion, early percentage of increases in ADCs, and preoperative ADCs. RESULTS Low pretreatment ADCs (<1.0 × 10(-3)mm(2)/s) were correlated with TRG 4 scores (p = .0011) and associated to extramural vascular invasion with ypN+ (85.7% positive predictive value for ypN+). During treatment, the mean percentage of increase in tumor ADC was significantly greater in the responders than in the nonresponders (p < .0001) and a >23% ADC increase had a 96.3% negative predictive value for TRG 4. In 9 of 16 complete responders, CRT-related tumor downsizing prevented ADC evaluations. The preoperative ADCs were significantly different (p = .0012) between the patients with and without downstaging (preoperative ADC ≥1.4 × 10(-3)mm(2)/s showed a positive and negative predictive value of 78.9% and 61.8%, respectively, for response assessment). The TRG 1 and TRG 2-4 groups were not significantly different. CONCLUSION Diffusion-weighted magnetic resonance imaging seems to be a promising tool for monitoring the response to CRT.

EURECCA colorectal: Multidisciplinary Mission statement on better care for patients with colon and rectal cancer in Europe

BACKGROUND Care for patients with colon and rectal cancer has improved in the last twenty years however still considerable variation exists in cancer management and outcome between European countries. Therefore, EURECCA, which is the acronym of European Registration of cancer care, is aiming at defining core treatment strategies and developing a European audit structure in order to improve the quality of care for all patients with colon and rectal cancer. In December 2012 the first multidisciplinary consensus conference about colon and rectum was held looking for multidisciplinary consensus. The expert panel consisted of representatives of European scientific organisations involved in cancer care of patients with colon and rectal cancer and representatives of national colorectal registries. METHODS The expert panel had delegates of the European Society of Surgical Oncology (ESSO), European Society for Radiotherapy & Oncology (ESTRO), European Society of Pathology (ESP), European Society for Medical Oncology (ESMO), European Society of Radiology (ESR), European Society of Coloproctology (ESCP), European CanCer Organisation (ECCO), European Oncology Nursing Society (EONS) and the European Colorectal Cancer Patient Organisation (EuropaColon), as well as delegates from national registries or audits. Experts commented and voted on the two web-based online voting rounds before the meeting (between 4th and 25th October and between the 20th November and 3rd December 2012) as well as one online round after the meeting (4th-20th March 2013) and were invited to lecture on the subjects during the meeting (13th-15th December 2012). The sentences in the consensus document were available during the meeting and a televoting round during the conference by all participants was performed. All sentences that were voted on are available on the EURECCA website www.canceraudit.eu. The consensus document was divided in sections describing evidence based algorithms of diagnostics, pathology, surgery, medical oncology, radiotherapy, and follow-up where applicable for treatment of colon cancer, rectal cancer and stage IV separately. Consensus was achieved using the Delphi method. RESULTS The total number of the voted sentences was 465. All chapters were voted on by at least 75% of the experts. Of the 465 sentences, 84% achieved large consensus, 6% achieved moderate consensus, and 7% resulted in minimum consensus. Only 3% was disagreed by more than 50% of the members. CONCLUSIONS It is feasible to achieve European Consensus on key diagnostic and treatment issues using the Delphi method. This consensus embodies the expertise of professionals from all disciplines involved in the care for patients with colon and rectal cancer. Diagnostic and treatment algorithms were developed to implement the current evidence and to define core treatment guidance for multidisciplinary team management of colon and rectal cancer throughout Europe.

A phase I/II trial of three-dimensionally planned concurrent boost radiotherapy and protracted venous infusion of 5-FU chemotherapy for locally advanced rectal carcinoma

BACKGROUND Improving the response to preoperative therapy may increase the likelihood of successful resection of locally advanced rectal cancers. Historically, the pathologic complete response (pCR) rate has been < approximately 10% with preoperative radiation therapy alone and < approximately 20% with concurrent chemotherapy and radiation therapy. METHODS AND MATERIALS Thirty-seven patients were enrolled on a prospective Phase I/II protocol conducted jointly at Washington University, St. Louis and the Catholic University of the Sacred Heart, Rome evaluating a three-dimensionally (3D) planned boost as part of the preoperative treatment of patients with unresectable or recurrent rectal cancer. Preoperative treatment consisted of 4500 cGy in 25 fractions over 5 weeks to the pelvis, with a 3D planned 90 cGy per fraction boost delivered once or twice a week concurrently (no time delay) with the pelvic radiation. Thus, on days when the boost was treated, the tumor received a dose of 270 cGy in one fraction while the remainder of the pelvis received 180 cGy. When indicated, nonaxial beams were used for the boost. The boost treatment was twice a week (total boost dose 900 cGy) if small bowel could be excluded from the boost volume, otherwise the boost was delivered once a week (total boost dose 450 cGy). Patients also received continuous infusion of 5-fluorouracil (1500 mg/m(2)-week) concurrently with the radiation as well as postoperative 5-FU/leucovorin. RESULTS All 37 patients completed preoperative radiotherapy as planned within 32--39 elapsed days. Twenty-seven underwent proctectomy; reasons for unresectability included persistent locally advanced disease (6 cases) and progressive distant metastatic disease with stable or smaller local disease (4 cases). Actuarial 3-year survival was 82% for the group as a whole. Among resected cases the 3-year local control and freedom from disease relapse were 86% and 69%, respectively.Twenty-four of the lesions (65%) achieved an objective clinical response by size criteria, including 9 (24%) with pCR at the primary site (documented T0 at surgery). The most important factor for pCR was tumor volume: small lesions with planning target volume (PTV) < 200 cc showed a 50% pCR rate (p = 0.02). There were no treatment associated fatalities. Nine of the 37 patients (24%) experienced Grade 3 or 4 toxicities (usually proctitis) during preoperative treatment. There were an additional 7 perioperative and 2 late toxicities. The most important factors for small bowel toxicity (acute or late) were small bowel volume (> or = 150 cc at doses exceeding 4000 cGy) and large tumor (PTV > or = 800 cc). For rectal toxicity the threshold is PTV > or = 500 cc. CONCLUSION 3D planned boost therapy is feasible. In addition to permitting the use of nonaxial beams for improved dose distributions, 3D planning provides tumor and normal tissue dose-volume information that is important in interpreting outcome. Every effort should be made to limit the treated small bowel to less than 150 cc. Tumor size is the most important predictor of response, with small lesions of PTV < 200 cc most likely to develop complete responses.

In vivo dosimetry by an aSi‐based EPID

A method for the in vivo determination of the isocenter dose, Diso, and mid-plane dose, Dm, using the transmitted signal St measured by 25 central pixels of an aSi-based EPID is here reported. The method has been applied to check the conformal radiotherapy of pelvic tumors and supplies accurate in vivo dosimetry avoiding many of the disadvantages associated with the use of two diode detectors (at the entrance and exit of the patient) as their periodic recalibration and their positioning. Irradiating water-equivalent phantoms of different thicknesses, a set of correlation functions F(w, l) were obtained by the ratio between St and Dm as a function of the phantom thickness, w, for a different field width, l. For the in vivo determination of Diso and Dm values, the water-equivalent thickness of the patients (along the beam central axis) was evaluated by means of the treatment planning system that uses CT scans calibrated in terms of the electron densities. The Diso and Dm values experimentally determined were compared with the stated doses D(iso,TPS) and D(m,TPS), determined by the treatment planning system for ten pelvic treatments. In particular, for each treatment four fields were checked in six fractions. In these conditions the agreement between the in vivo dosimetry and stated doses at the isocenter point were within 3%. Comparing the 480 dose values obtained in this work with those obtained for 30 patients tested with a similar method, which made use of a small ion-chamber positioned on the EPIDs to obtain the transmitted signal, a similar agreement was observed. The method here proposed is very practical and can be applied in every treatment fraction, supplying useful information about eventual patient dose variations due to the incorrect application of the quality assurance program based on the check of patient setup, machine setting, and calculations.