Mandard Tumor Regression Grade Research Articles

Prognostic classification of histopathologic response to neoadjuvant therapy in esophageal adenocarcinoma.

To evaluate the histopathologic response to neoadjuvant therapy in esophageal adenocarcinoma according to impact on prognosis and to suggest a classification for clinical routine. Measures of histopathologic response to neoadjuvant treatment of esophageal cancer such as Mandard tumor regression grading focus on the effect on the primary tumor. Although lymph node infiltration is of significant prognostic importance, this criterion is mostly not included in the response classifications. A total of 370 patients (89% males, median age: 61 years) with neoadjuvant radiochemotherapy (40 Gy, 5-FU, cisplatin) or chemotherapy (MAGIC or FLOT) for cT3, Nx, M0 esophageal adenocarcinoma were included in the analysis. All patients had undergone transthoracic en bloc esophagectomy, with a median of 27 resected lymph nodes and a R0-resection rate of 92%. Histopathologic regression grading differentiated major or minor response according to less or more than 10% vital cells in the primary tumor. The lymph nodes were classified as ypN0 or ypN+. From the patients with R0 resection and M0 category, 3 groups with significantly different 5-year survival rates (5-YSR) could be differentiated: 1. Major response and ypN0 (n=100) with 5-YSR of 64% 2. Either major response and ypN+ (n=34) 5-YSR 42% or minor response and ypN0 (n=84) 5-YSR 44%, together 42% 5-YSR 3. Minor response and ypN+ (n=111) and 5-YSR of 18%. A combined classification of primary tumor regression and lymph node status in 3 grades represents a simple and reproducible prognostic classification of the effect of neoadjuvant treatment in esophageal adenocarcinoma.

Comparison of (18)F-FDG PET/CT methods of analysis for predicting response to neoadjuvant chemoradiation therapy in patients with locally advanced low rectal cancer.

The aim of this study was to prospectively investigate the predictive value of (18)F-FDG PET/CT semiquantitative parameters for locally advanced low rectal cancer (LARC) treated by neoadjuvant chemoradiation therapy (nCRT). 68 patients with LARC had (18)F-FDG PET/CT scans twice (baseline and 5-6 weeks post-nCRT). All patients underwent surgery with preservation of the sphincter 8 weeks later. (18)F-FDG PET/CT analysis was performed by visual response assessment (VRA) and semiquantitative parameters: SUVmax(baseline), SUVmean(baseline), MTV(baseline), TLG(baseline), SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), TLG(post-nCRT); ΔSUVmax and mean and Response indexes (RImax% and RImean%). Assessment of nCRT tumor response was performed according to the Mandard's Tumor Regression Grade (TRG) and (y)pTNM staging on the surgical specimens. Concordances of VRA with TRG, and with (y)pTNM criteria were evaluated by Cohen's K. Results were compared by t student test for unpaired groups. ROC curve analysis was performed. VRA analysis of post-nCRT (18)F-FDG PET/CT scan for the (y)pTNM outcome showed sensitivity, specificity, accuracy, PPV, and NPV of 87.5%, 66.7%, 83.8%, 92.5%, and 53.3%, respectively. Concordances of VRA with TRG and with (y)pTNM were moderate. For the outcome variable TRG, the statistical difference between responders and non-responders was significant for SUVmax(post-nCRT) and RImean%; for the outcome variable (y)pTNM, there was a significant difference for MTV(baseline), SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), RImax%, and RImean%. ROC analysis showed better AUCs: for the outcome variable TRG for SUVmax(post-nCRT), SUVmean(post-nCRT), and RImean%; for the outcome variable (y)pTNM for MTVbaseline, SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), RImax%, and RImean%. No significant differences among parameters were found. Qualitative and semiquantitative evaluations for (18)F-FDG PET/CT are the optimal approach; a valid parameter for response prediction has still to be established.

Primary systemic treatment and concomitant low dose radiotherapy for breast cancer: Final results of a prospective phase II study

BackgroundTo evaluate the efficacy of preoperative low dose fractionated radiotherapy (LD-FRT) and chemotherapy in breast cancer. Materials and methodsPatients with stage IIA–IIIA breast cancer, received LD-FRT (0.40 Gy bid, on day 1 and 2, for 6 cycles) to primary tumor volume and concurrent chemotherapy with non-pegylated liposomal anthracycline and docetaxel. Pathological response was assessed by Mandard Tumor Regression Grade (TRG). We evaluated the pathological major response rate (PMRR) as TRG1 and TRG2. The expected outcome was a PMRR of 60%. The accrual was determined by the single proportion powered analysis (α = 0.05, power = 0.8). ResultsTwentyone patients were enrolled. No grade 2–4 acute skin and hematological toxicity was observed. TRG1 was obtained in 3 patients (14.3%), TRG2 in 4 patients (19%). The PMRR was 33.3%; it does not concur with the expected result, but is similar to that of chemotherapy alone. According to molecular subtype, 2/11 luminal A patients and 4/6 luminal B patients obtained a PMRR to preoperative treatment (35.3%); 1/4 basal like patients reported TRG1 (25%). ConclusionsLD-FRT concomitant with primary systemic treatment has a good toxicity profile. The response rate is consistent with that of chemotherapy alone, and suggests different interactions between low dose radiotherapy and molecular subtypes. Additional investigations are planned.

Biological Target Volume Overlapping Segmentation System Method for Avoiding False-Positive PET Findings in Assessing Response to Neoadjuvant Chemoradiation Therapy in Rectal Cancer

FDG PET/CT has a recognized high predictive power to assess the response to neoadjuvant chemoradiation therapy (CRT) in patients affected by locally advanced rectal cancer (LARC), but a relatively high number of false-positive findings decrease its specificity: with the aim to solve this problem, a new method of imaging analysis is here proposed. The new method here described, named Biological target volume (BTV) Overlapping Segmentation System (BOSS), has been applied on 24 consecutive patients with LARC that were all previously classified as nonresponders to CRT by means of the response index criterion that is adopted in our center. The BOSS method is based on the quantification of the amount of superimposition between pretreatment and posttreatment BTV. All BTVpre was down using a threshold of 60% of SUVmax in the tumor (BTV60). The results (overlap volumes and percentage of overlap volumes) were then matched up with postoperative pathology classified by the Mandard's tumor regression grade (TRG) system. Eleven patients were classified as responders (TRG1-2) and 13 as nonresponders (TRG 3-5). Among all the results obtained by BOSS method, only the percentage of overlap volume data between BTV60 and BTVpost (%Over_60) was able to correctly distinguish between responders and nonresponders. In our experience, a cutoff of 56% on the %Over_60 provided the best results in terms of true negative (11 cases), true positive (12 cases), false negative (1 case), and false positive (none). This new method, we developed, appears able to unmask the false-positive cases, improving the specificity of FDG PET/CT to predict the response to CRT patients with LARC.

Mandard Tumour Regression Grade, Perineural Invasion, Circumferential Resection Margin and Post-chemoradiation Nodal Status Strongly Predict Outcome in Locally Advanced Rectal Cancer Treated with Preoperative Chemoradiotherapy

AimsThe pathology of tumours after chemo/radiotherapy for locally advanced rectal cancer can be difficult to interpret. The ypTNM staging does not accurately predict outcomes. Therefore, we developed a new prognostic index for this purpose. Materials and methodsThe Nottingham Rectal Cancer Prognostic Index (NRPI) is based on a study of 158 patients with locally advanced rectal cancer treated with preoperative chemo/radiotherapy at Nottingham University Hospital between April 2001 and December 2008. Patients were treated with radiotherapy to a dose of 50 Gy in 25 fractions over 5 weeks with/without concurrent capecitabine chemotherapy. Surgery was carried out after an interval of 6–10 weeks. Factors found to be significant on univariate analysis to predict for disease-free (DFS) and overall survival were further explored in multivariate analysis. The significant factors (Mandard tumour regression grade, perineural invasion, circumferential resection margin status and nodal status) were weighted to establish a score for the index. The median follow-up was 40 months (range 3–90 months). ResultsOn survival analysis, four distinct prognostic groups were found: Score 0 = excellent prognosis, 1–3 = good prognosis, 4–8 = moderate prognosis, 9–14 = poor prognosis. The NRPI significantly predicted both DFS and overall survival (P < 0.0001). DFS at 5 years was 95, 63, 25 and 0% for the four groups. On multivariate analysis the NRPI was found to be the strongest predictor of DFS including nodal and circumferential resection margin status (P < 0.0001). It was a stronger predictor of overall survival than the American Joint Committee on Cancer/Dukes staging (P < 0.0001). ConclusionsThe NRPI allocates patients into distinct prognostic categories. This seems to be a much stronger predictive factor than the American Joint Committee on Cancer/Dukes staging. This requires further validation, but seems to be a useful clinical index for future studies.

DNA content analysis of colorectal cancer defines a distinct ‘microsatellite and chromosome stable’ group but does not predict response to radiotherapy

Colorectal cancers (CRC) are thought to have genetic instability in the form of either microsatellite instability (MSI) or chromosomal instability (CIN). Recently, tumours have been described without either MSI or CIN, that is, microsatellite and chromosome stable (MACS) CRCs. We investigated the (i) frequency of the MACS-CRCs and (ii) whether this genotype predicted responsiveness to neoadjuvant chemoradiotherapy. To examine the frequency of MACS-CRCs, DNA content (ploidy) was examined in 89 sporadic microsatellite-stable CRCs using flow cytometry. The tumours were also screened for mutations in KRAS/BRAF/TP53/PIK3CA by QMC-PCR. To examine the value of tumour ploidy in predicting response to chemoradiotherapy, DNA content was tested in a separate group of 62 rectal cancers treated with neoadjuvant chemoradiotherapy. Fifty-one of 89 CRCs (57%) were aneuploid and 38 (43%) were diploid. There was no significant association between mutations in TP53/KRAS/BRAF/PIK3CA and ploidy. Testing of association between mutations revealed only mutual exclusivity of KRAS/BRAF mutation (P<0.001). Of the 62 rectal cancers treated with neoadjuvant chemoradiotherapy, 22 had responded (Mandard tumour regression grade 1/2) and 40 failed to respond (Grade 3-5). Twenty-five of 62 (40%) tumours were diploid, but there was no association between ploidy and response to therapy. We conclude that MACS-CRCs form a significant proportion of microsatellite-stable CRCs with a mutation profile overlapping that of CRCs with CIN. A diploid genotype does not, however, predict the responsiveness to radiotherapy.

The relationship between tumor cell density in the pretreatment biopsy and survival after chemotherapy in OE02 trial esophageal cancer patients.

49 Background: Neoadjuvant chemotherapy (chemo) followed by surgery is the standard treatment for UK patients with resectable oesophageal cancer [OeC] since the OE02 trial (Allum et al. J. Clin. Oncol, 2009), yet some patients receive no benefit from chemo. We investigated whether tumour cell density (TCD) in the pre-chemo biopsy can predict patient benefit from chemo among OE02 patients. Methods: Hematoxylin and eosin stained diagnostic biopsy slides from 281 OE02 trial OeC patients reflective of the whole trial population based on patient characteristics and survival (70% adenocarcinoma, surgery alone: n=141; chemo followed by surgery: n=140) were digitized. TCD (percentage of epithelial tumor cells/viable tumor mass) was quantified by point counting and cut offs for overall survival analyses were identified. The relationship between TCD and clinicopathological data and its predictive value (heterogeneity of treatment effect) were assessed. Results: TCD ranged between 16-99% with 85% of cases in the 25-75% range. TCD was initially divided into tertiles. The treatment hazard ratio (HR) was examined within each tertile showing evidence of heterogeneity with clear benefit from chemo seen only in the middle tertile. Cut offs were refined through examination of treatment HR within TCD quintiles. Treatment HRs were 1.25 (95%confidence interval 0.66, 2.35), 1.94 (1.39, 2.71) and 0.65 (0.36, 1.18), respectively, for TCD &lt;40% (n=46), 40-70% (n=183) and &gt;70% (n=52), suggesting that only patients with 40-70% TCD benefit from neoadjuvant chemo (HR&gt;1 favours chemo, heterogeneity p=0.006). Low Mandard tumor regression grade (1-3 versus 4-5) was related to a lower biopsy TCD (median: 47% versus 56%, p=0.0402). Conclusions: TCD appears to be able to predict survival benefit from neoadjuvant chemo in OeC patients and is associated with tumour regression. Our result requires validation in an independent dataset to confirm its potential clinical utility. If validated, TCD measurement in the diagnostic biopsy could be used to determine which OeC patients would benefit from neoadjuvant chemo versus those who would benefit most from management with surgery alone.

The prognostic value of tumour regression grade following neoadjuvant chemoradiation therapy for rectal cancer

To date, there is no uniform consensus on whether tumour regression grade (TRG) is predictive of outcome in rectal cancer. Furthermore, the lack of standardization of TRG grading is a major source of variability in published studies. The aim of this study was to evaluate the prognostic impact of TRG in a cohort of patients with locally advanced rectal cancer treated with neoadjuvant chemoradiation therapy (CRT). In addition to the Mandard TRG, we utilized four TRG systems modified from the Mandard TRG system and applied them to the cohort to assess which TRG system is most informative. One-hundred and fifty-three patients with a T3/T4 and/or a node-positive rectal cancer underwent neoadjuvant 5-fluorouracil-based CRT followed by surgical resection. Thirty-six (23.5%) patients achieving complete pathological response (ypCR) had a 5-year disease-free survival (DFS) rate of 100% compared with a DFS rate of 74% for 117 (76.5%) patients without ypCR (P=0.003). The Royal College of Pathologists (RCPath) TRG best condenses the Mandard five-point TRG by stratifying patients into three groups with distinct 5-year DFS rates of 100%, 86% and 67%, respectively (P=0.001). In multivariate analysis, pathological nodal status and circumferential resection margin (CRM) status, but not TRG, remained significant predictors of DFS (P=0.002, P=0.035 and P= 0.310, respectively). Our findings support the notion that ypCR status, nodal status after neoadjuvant CRT and CRM status, but not TRG, are predictors of long-term survival in patients with locally advanced rectal cancer.

Perioperative epirubicin, oxaliplatin, and capectabine (EOX) in locally advanced resectable gastroesophageal junction and gastric adenocarcinoma.

e15142 Background: Perioperative chemotherapy with epirubicin, cisplatin and fluorouracil (ECF) confers a 13% absolute 5-year survival benefit over surgery alone in resectable gastroesophageal cancer. In the metastatic setting, the EOX regimen is at least as effective as ECF, with a favourable toxicity profile. This retrospective analysis presents the experience of a high-volume tertiary referral center with perioperative EOX in patients with resectable GEJ and gastric adenocarcinoma. Methods: Patients with cTxN+/cT3N0 gastroesophageal adenocarcinoma treated between 2006-2012 with perioperative EOX (epirubicin 50mg/m2 d1 q22d, oxaliplatin 130mg/m2 d1 q22d and capecitabine 625 mg/m2 bd d1-21 q22d), given as three neoadjuvant and three adjuvant cycles, were retrospectively identified from a prospectively recorded upper gastrointestinal cancer database. Efficacy and toxicity data were assessed. Results: 52 patients, including 41 (82%) males, with a median age of 62 (range 35-79) received perioperative EOX with curative intent. GEJ tumours represented 39 (75%) of cases, and the others were gastric cancers. 47 patients (90%) completed 3 cycles of neoadjuvant EOX. One patient died of non-neutropenic sepsis after cycle 2. 44 (85%) of patients progressed to surgery, 5 of whom were deemed unresectable. 28 (71%) surgeries were D2 resections, and the R0 resection rate was 67%. There was one postoperative death, due to pancreatitis. 28 (54%) of patients commenced adjuvant EOX, and 25 (48%) completed the planned treatment. Grade 3-4 toxicities were observed in 17% of patients, with the commonest being fatigue (8%) and nausea (4%). Pathological response rate, as defined by Mandard Tumour Regression Grade 1-3, was seen in 26%, with 3 (6%) pathological complete response. The median progression-free survival was 7 months, with a median overall survival of 22 months, and a 2-year survival rate of 45%. Conclusions: In our institution, perioperative EOX in gastroesophageal cancer is associated with a reasonable safety profile, and efficacy consistent with that reported in the MAGIC trial.

Abstract 4695: Predictive role of FDG PET-CT in monitoring locally advanced rectal cancer (LARC) during preoperative radiochemotherapy with an experimental bevacizumab schedule.

Abstract Objectives : We have shown that pathological regression of LARC and relapse free survival can be predicted by early changes in FDG uptake during preoperative radiochemotherapy. We have attempted to improve efficacy of our neo-adjuvant treatment by adding an experimental bevacizumab (BEV) schedule. FDG PETCT was utilized to monitor response and correlate with pathological outcome. Methods : Forty six patients with poor prognosis LARC received 3 biweekly courses of oxaliplatin/ raltitrexed (day 1) and FU/ folinic acid (day 2) during pelvic RT (45 Gy). BEV (5 mg/kg) was administered on day -4 for the first 2 courses. PET-CT was performed at baseline, on day 12 and prior to surgery and lesion TLG (mean SUV x volume) values determined. Pathologic response was defined using a modified Mandard tumor regression grade (TRG) scale. Responders were defined as TRG1-2, non-responders as TRG3-4. Results : Thirty-seven patients (80%) showed pathologic response (65% with previous scheme). Eight patients (17%, previously 35%) were non-responders. Responders showed significantly higher TLG reduction on day 12 PET-CT (median -72% range -90%+31%) compared to non-responders (TRG3-4, median -38%, range -45% +25%, p &amp;lt; 0.05), confirming previous findings. Preoperative PET-CT studies, on the other hand, were not predictive of pathologic response (responders TLG change median -92%, range -100% +4%, non-responders median 86%, range -94%-76%, p = ns). Ongoing studies to define a correlation between FDG uptake and biomarkers of angiogenesis such as Circulating endothelial cells (CEC) will be presented. Conclusions : Our findings indicate that the current scheme significantly increases pathologic response. PET-CT confirms to be a powerful early surrogate marker of treatment efficacy. PET-CT may be used to tailor more aggressive treatment for non-responsive patient Citation Format: Antonio Avallone, Paolo Delrio, Biagio Pecori, Fabiana Tatangelo, Elena Di Gennaro, Antonella Petrillo, Vincenzo Rosario Iaffaioli, Alessandra Leone, Corradina caracò, Alfredo Budillon, Secondo Lastoria, Luigi Aloj. Predictive role of FDG PET-CT in monitoring locally advanced rectal cancer (LARC) during preoperative radiochemotherapy with an experimental bevacizumab schedule. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4695. doi:10.1158/1538-7445.AM2013-4695

Ultrasound elastography in patients with rectal cancer treated with chemoradiation

ObjectiveThe current literature has described several predictive markers in rectal cancer patients treated with chemoradiation, but so far none of them have been validated for clinical use. The purpose of the present study was to compare quantitative elastography based on ultrasound measurements in the course of chemoradiation with tumor response based on T stage classification and the Mandard tumor regression grading (TRG). Materials and methodsWe prospectively examined 31 patients with rectal cancer planned for high dose radiochemotherapy. The tumor and the mesorectal fat elasticity were measured using the Acoustic Radiation Force Impulse to generate information on the mechanical properties of the tissue. The objective quantitative elastography shear wave velocity was compared to the T stage classification and TRG. ResultsThe baseline mean tumor elasticity was 3.13m/s. Two and six weeks after the start of chemoradiation the velocities were 2.17m/s and 2.11m/s, respectively. The difference between baseline velocity and velocities during the treatment course was statistically significant, (p<0.0001). Patients with tumor confined to the rectal wall at histopathology (ypT1-2) had a mean elasticity measurement after two weeks of treatment of 1.95m/s, whereas tumors invading the mesorectal fat (ypT3-4) had a velocity of 2.47m/s, (p<0.05). The mean elasticity tended to be lower (1.99m/s) after two weeks in patients with TRG 1–2 responses in contrast to 2.24m/s in those with TRG 3–4. ConclusionUltrasound elastography after two weeks of chemoradiation seems to hold early predictive information to the pathological T stage.

The value of 18F-FDG PET/CT for assessing the response to neoadjuvant therapy in locally advanced rectal cancer

Neoadjuvant radiochemotherapy (RCT) is an accepted treatment for locally advanced rectal cancer (LARC) that improves surgical outcomes. If a pathological complete response is achieved, conservative surgery can be considered. The objective of our study was to assess the reliability of (18)F-FDG PET/CT for evaluating the response to neoadjuvant RCT in LARC. We prospectively studied 41 patients diagnosed with LARC and candidates for neoadjuvant RCT. PET/CT was performed before RCT and again 7weeks later. A visual and semiquantitative analysis was carried out. The pathological response was classified according to the Mandard tumour regression grade (TRG). We analysed: (a) the relationship between TRG and the result of the posttreatment PET/CT scan, and (b) the correlation between the percentage of pathological response and the percentage decrease in SUVmax according to the response index (RI). The mean SUVmax of the rectal lesions at diagnosis was 13.6 and after RCT 3.96. The mean RI was 65.32%. Sensitivity was 88.88%, specificity 92.86%, positive predictive value 96%, negative predictive value 81%. Of the 41 patients, 8 had TRG I (all negative PET/CT); 6 had TRG II (5 negative, 1 positive PET/CT); 16 had TRG III (13 positive, 3 negative PET/CT); 9 had TRG IV (all positive PET/CT); 2 had TRG V (all positive PET/CT). Of the 14 patients classified as responders (TRG I, II), 13 (92.86%) had negative PET/CT. Of the 27 patients classified as nonresponders (TRG III-V), 24 (88.88%) had positive PET/CT. Differences were statistically significant (p < 0.0001). The RI in responders was 79.9% and in nonresponders was 60.3%. Differences were statistically significant (p < 0.037). PET/CT is a reliable technique for assessing response to neoadjuvant RCT in LARC, with a view to considering more conservative surgical treatment. The combination of the visual and semiquantitative analysis increases the diagnostic validity of PET/CT.

567P - Neoadjuvant Multidisciplinary Phase II Study (BRANCH) of an Early Bevacizumab Schedule Plus Chemo-Radiation Therapy in Rectal Cancer: Efficacy, Safety, and Biomarkers

ABSTRACT Background In BRANCH study we assess the safety and efficacy of an experimental schedule of early (4 days before) bevacizumab (BEV) added to neoadjuvant chemotherapy (CT) and radiotherapy (RT) in poor-risk locally advanced rectal cancer (pLARC) patients (pts) and explore the potential of circulating endothelial cells (CECs) and tumor lesion glycolysis (TLG) as surrogate markers of pathological response(PR). Patients and methods 46 pts (cT4, cN + , cT3≤ 5 cm from the anal verge and/or positive circumferential margin, M1 resectable) received 3 biweekly courses of oxaliplatin (100 mg/m2)/raltitrexed (2.5 mg/m2) on day 1, and 5-FU (800 mg/m2)/folinic acid (250 mg/m2) on day 2 during pelvic RT (45 Gy). BEV (5 mg/kg) was given biweekly 4 days before beginning of CT/RT for 2 courses. Toxicity was graded with NCI-CTC v.3. PR was defined using Mandard tumor regression grade (TRG). According to the Simon's two-stage design, assuming an hypothesis of a 50% TRG1 (complete tumor regression) (α error = 0.05, β error = 0.20), at least 6/16 TRG1 should be obtained to continue accrual to 46 pts. CECs and TLG were evaluated at baseline (BL) on day 10 and before surgery, by flow cytometry and FDG-PET, respectively. Statistical analysis was by Mann-Whitney test. Results We obtained 23 TRG1 (50%), 14 TRG2 (30%) and 8 TRG3-4 (17%). Grade ¾ neutropenia was the most common adverse event (13/46 pts, 28%). TLG reduction on day 10 vs BL was significantly higher in responders TRG1-2 compared to non-responders TRG3-4 pts (median -72%, range -90% + 31% vs -38%, range -45% + 25%; p Conclusions Current scheme of BEV plus CT and RT appears safe and active, yielding high rate of TRG1 and TRG2 responses in pLARC. Early FDG-PET and CECs evaluation emerged as potential biomarkers for treatment selection to be incorporated in design of future studies with this regimen. CEP and citochine data will be provided at the meeting. Disclosure All authors have declared no conflicts of interest.

Gene expression profiles of tumor regression grade in locally advanced rectal cancer after neoadjuvant chemoradiotherapy

Tumor regression grading (TRG) reportedly has prognostic value in rectal cancer patients after pre-operative chemoradiotherapy (CRT). The aim of this retrospective study was to differentiate gene expression profiles based on TRG in residual cancer cells after CRT. We evaluated pathological response using the criteria of four TRG systems: the Japanese Society for the Cancer of Colon and Rectum (JSCCR), Mandard, Dworak and Rödel. Total RNA was obtained using microdissection from 52 locally advanced rectal cancer specimens from patients who underwent pre-operative CRT to examine the expression levels of 20 genes [PCNA, MKI67, CDKN1A (p21Cip1), CDK2, CHEK1, PDRG1, LGR5, PROM1 (CD133), CD44, SOX2, POU5F1 (OCT4), LKB1, VEGF, EGFR, HGF, MET, HIF1, GLUT1, BAX and BCL2] using real-time quantitative RT-PCR. Gene expression was compared across the four TRG systems. LGR5 gene expression levels in CRT non-responders were significantly higher than in responders in all four grading systems. Patients with elevated PDRG1 and GLUT1 gene expression had poor pathological response in three TRG systems (JSCCR, Dworak and Rödel). MKI67 gene expression in non-responders was significantly higher than in responders in two grading systems (JSCCR and Rödel). While, BAX gene expression in responders was significantly higher than in non-responders in the Mandard TRG system. The results of this study suggest that TRG may reflect characteristics, such as proliferative activity, stemness potency and resistance to hypoxia, of residual cancer cells following pre-operative CRT.

Abstract LB-219: Neoadjuvant multidisciplinary phase II study (BRANCH) of an early bevacizumab schedule plus chemo-radiation therapy in rectal cancer: efficacy, safety, and biomarkers.

Abstract BACKGROUND: The benefits of combining bevacizumab (BEV) plus chemotherapy have thus far been rather modest, stimulating interest in developing novel effective combination schedule as well as valid predictive biomarkers. Several evidences support the hypothesis that BEV can normalize the abnormal tumor vasculature, resulting in more efficient delivery of drugs and oxygen to cancer cells and that this effect seems to be transient and with a relatively narrow therapeutic window. In BRANCH study (NCT01481545) we assess the safety and efficacy of an experimental schedule of early (4 days before) BEV added to neoadjuvant chemotherapy (CT) and radiotherapy (RT) in poor-risk locally advanced rectal cancer (pLARC) patients (pts) and explore the potential of circulating endothelial cells (CECs) and tumor lesion glycolysis (TLG) as surrogate markers of pathological response. PATIENTS AND METHODS: 46 pts (cT4, cN+, cT3≤ 5 cm from the anal verge and/or positive circumferential margin, M1 resectable) received 3 biweekly courses of oxaliplatin (100 mg/m2)/raltitrexed (2.5 mg/m2) on day 1, and 5-FU (800 mg/m2)/folinic acid (250 mg/m2) on day 2 during pelvic RT (45 Gy). BEV (5 mg/kg) was given biweekly 4 days before beginning of CT/RT for 2 courses. Toxicity was graded with NCI-CTC v.3. Pathological response was defined using a modified Mandard tumor regression grade (TRG). According to the Simon's two-stage design, assuming an hypothesis of a 50% TRG1 (complete tumor regression) (α error=0.05, β error=0.20), at least 6/16 TRG1 should be obtained to continue accrual to 46 pts. CECs were quantified at baseline (BL) before BEV, at several time points thereafter during treatment and before surgery, by flow cytometry. TLG, was evaluated at BL, on day 10 and before surgery, by FDG-PET. Statistical analysis was by Mann-Whitney test. RESULTS: TRG1 required by statistical design was reached in the first 16 pts and in the final 46 pts: 23 TRG1 (50%), 14 TRG2 (30%) and 8 TRG3-4 (17%). One pt refused surgery. Grade ¾ neutropenia was the most common adverse event (13/46 pts, 28%). TLG reduction on day 10 vs BL was significantly higher in responders TRG1-2 compared to non-responders TRG3-4 pts (median -72%, range -90%+31% vs -38%, range -45%+25%; p &amp;lt; 0.05). Median CECs at BL were higher in TRG1-2 vs TRG3-4 pts (median 0.22/µl, range 0-3.98 vs 0/µl, range 0-0.174; p=0.009). Moreover, in TRG1-2 pts CECs were significantly reduced on day 10 vs BL (median 0.014/µl, range 0-2.29; p=0.002). This pattern was not seen in TRG3-4 pts with a tendency toward increased levels (median 0.316/µl, range 0-2.64; p=0.097). CONCLUSIONS: Early schedule of BEV plus CT and RT appears safe and active yielding high rate of TRG1 and TRG2 responses in pLARC. Early FDG-PET and CECs evaluation emerged as potential biomarkers for treatment selection to be incorporated in design of future studies with this regimen. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-219. doi:1538-7445.AM2012-LB-219

Contrast-enhanced ultrasonography assessment of gastric cancer response to neoadjuvant chemotherapy

To quantitatively assess the ability of double contrast-enhanced ultrasound (DCUS) to detect tumor early response to pre-operative chemotherapy. Forty-three patients with gastric cancer treated with neoadjuvant chemotherapy followed by curative resection between September 2011 and February 2012 were analyzed. Pre-operative chemotherapy regimens of fluorouracil + oxaliplatin or S-1 + oxaliplatin were administered in 2-4 cycles over 6-12 wk periods. All patients underwent contrast-enhanced computed tomography (CT) scan and DCUS before and after two courses of pre-operative chemotherapy. The therapeutic response was assessed by CT using the response evaluation criteria in solid tumors (RECIST 1.1) criteria. Tumor area was assessed by DCUS as enhanced appearance of gastric carcinoma due to tumor vascularity during the contrast phase as compared to the normal gastric wall. Histopathologic analysis was carried out according to the Mandard tumor regression grade criteria and used as the reference standard. Receiver operating characteristic (ROC) analysis was used to evaluate the efficacy of DCUS parameters in differentiating histopathological responders from non-responders. The study population consisted of 32 men and 11 women, with mean age of 59.7 ± 11.4 years. Neither age, sex, histologic type, tumor site, T stage, nor N stage was associated with pathological response. The responders had significantly smaller mean tumor size than the non-responders (15.7 ± 7.4 cm vs 33.3 ± 14.1 cm, P < 0.01). According to Mandard's criteria, 27 patients were classified as responders, with 11 (40.7%) showing decreased tumor size by DCUS. In contrast, only three (18.8%) of the 16 non-responders showed decreased tumor size by DCUS (P < 0.01). The area under the ROC curve was 0.64, with a 95%CI of 0.46-0.81. The effects of several cut-off points on diagnostic parameters were calculated in the ROC curve analysis. By maximizing Youden's index (sensitivity + specificity - 1), the best cut-off point for distinguishing responders from non-responders was determined, which had optimal sensitivity of 62.9% and specificity of 56.3%. Using this cut-off point, the positive and negative predictive values of DCUS for distinguishing responders from non-responders were 70.8% and 47.4%, respectively. The overall accuracy of DCUS for therapeutic response assessment was 60.5%, slightly higher than the 53.5% for CT response assessment with RECIST criteria (P = 0.663). Although the advantage was not statistically significant, likely due to the small number of cases assessed. DCUS was able to identify decreased perfusion in responders who showed no morphological change by CT imaging, which can be occluded by such treatment effects as fibrosis and edema. DCUS may represent an innovative tool for more accurately predicting histopathological response to neoadjuvant chemotherapy before surgical resection in patients with locally-advanced gastric cancer.

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

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. 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. 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. Diffusion-weighted magnetic resonance imaging seems to be a promising tool for monitoring the response to CRT.

Serum Proteomic Profiling Reveals That Pretreatment Complement Protein Levels are Predictive of Esophageal Cancer Patient Response to Neoadjuvant Chemoradiation

To identify serum-based biomarkers predicting response to neoadjuvant chemoradiotherapy (neo-CRT) in esophageal cancer. Increasingly, the standard of care for esophageal cancer involves neo-CRT followed by surgery. The identification of biomarkers predicting response to therapy may represent a major advance, enabling clinical trials and improved outcomes. Patients with esophageal cancer (n = 31) received a standard neo-CRT regimen. Histopathologic response to therapy was assessed by using the Mandard tumor regression grade (TRG) classification. Serum was collected pretreatment and at 24-hour and 48-hour time points into treatment. Serum samples were analyzed by using Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry and enzyme-linked immunosorbent assay. A leave-one-out cross-validation predictive algorithm assessed the ability of validated biomarkers to correctly predict therapeutic outcome. Fifty-one percent (16) of patients were poor responders (TRG 3-5), whereas 49% (15) responded well (TRG 1-2). On CM10 biochips, serum expression of 9 protein peaks was significantly different between the response groups. Two differential spectrum peaks were identified as complement C4a and C3a and were subsequently analyzed by enzyme-linked immunosorbent assay. Pretreatment serum C4a and C3a levels were significantly higher in poor responders versus good responders. Subdivision of the response groups by TRG indicated an inverse correlation between levels of C4a and C3a and pathological response to neo-CRT. The leave-one-out cross-validation analysis revealed that these serum proteins could predict response to neo-CRT with a sensitivity and specificity of 78.6% and 83.3%, respectively. This translational application of proteomics technology identifies pretreatment serum levels of C4a and C3a as predictive biomarkers of response. Large validation studies in an independent cohort are merited.

Pretreatment Transcriptional Profiling for Predicting Response to Neoadjuvant Chemoradiotherapy in Rectal Adenocarcinoma

Patients presenting with locally advanced rectal cancer currently receive preoperative radiotherapy with or without chemotherapy. Although pathologic complete response is achieved for approximately 10% to 30% of patients, a proportion of patients derive no benefit from this therapy while being exposed to toxic side effects of treatment. Therefore, there is a strong need to identify patients who are unlikely to benefit from neoadjuvant therapy to help direct them toward alternate and ultimately more successful treatment options. In this study, we obtained expression profiles from pretreatment biopsies for 51 rectal cancer patients. All patients underwent preoperative chemoradiotherapy, followed by resection of the tumor 6 to 8 weeks posttreatment. Gene expression and response to treatment were correlated, and a supervised learning algorithm was used to generate an original predictive classifier and validate previously published classifiers. Novel predictive classifiers based on Mandard's tumor regression grade, metabolic response, TNM (tumor node metastasis) downstaging, and normal tissue expression profiles were generated. Because there were only 7 patients who had minimal treatment response (>80% residual tumor), expression profiles were used to predict good tumor response and outcome. These classifiers peaked at 82% sensitivity and 89% specificity; however, classifiers with the highest sensitivity had poor specificity, and vice versa. Validation of predictive classifiers from previously published reports was attempted using this cohort; however, sensitivity and specificity ranged from 21% to 70%. These results show that the clinical utility of microarrays in predictive medicine is not yet within reach for rectal cancer and alternatives to microarrays should be considered for predictive studies in rectal adenocarcinoma.

Abstract 4124: Pre-treatment complement system serum protein levels predict pathological response to neoadjuvant chemoradiotherapy for esophageal cancer

Abstract Introduction: Esophageal cancer has one of the worst prognosis of all cancers, and its incidence is increasing rapidly in the Western world. The standard of care for patients with esophageal cancer involves neoadjuvant chemoradiotherapy (neo-CRT) followed by surgery. Unfortunately, only ∼30% of esophageal cancer patients respond to neo-CRT. The aim of this study was to analyse the serum proteome early into neo-CRT to reveal biomarkers indicative of response to therapy. Methods: 31 esophageal cancer patients received a standard neo-CRT regimen. Pathological response to therapy was assessed using the Mandard Tumour Regression Grade system. Serum was collected at pre-treatment, 24 h and 48 h timepoints into treatment. Albumin/IgG-depleted serum samples were analyzed using SELDI-TOF-MS. Protein/peptide expression difference mapping was performed and the data applied to the EPO-KB database. Subsequently, high-scoring candidates were assayed by ELISA. A leave-one-out cross validation (LOOCV) predictive algorithm was employed to assess the ability of candidate biomarkers to correctly predict therapeutic outcome. Results: 16 patients had a poor response to therapy, while 15 had a good response. On CM10 chips, 9 protein peaks were significantly different between the two treatment response groups, some at baseline, others at 24 h and 48 h into neo-CRT. SELDI spectral peaks m/z_8617.685 and m/z_8928.422 were identified as the complement proteins C4a and C3a, respectively, via the EPO-KB. ELISA revealed significantly higher pre-treatment levels of C4a and C3a in serum from poor versus good responders. Subdivision of the response groups by TRG indicated an inverse correlation between levels of C4a and C3a and pathological response to neo-CRT. In a pre-treatment setting, LOOCV analysis revealed that these two serum proteins could predict patient response to neo-CRT with a sensitivity and specificity of 78.6% and 83.3%, respectively. Conclusion: In a relatively non-invasive approach, this study has identified that pre-treatment levels of serum C4a and C3a are potential pre-treatment biomarkers predicting response to neo-CRT for esophageal cancer. Additional serum proteins are being validated to further improve the sensitivity and specificity of predicting esophageal patient response to treatment. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4124. doi:10.1158/1538-7445.AM2011-4124