Evolutionary patterns of chromosomal instability and mismatch repair deficiency in proximal and distal colorectal cancer.

AIM: Colorectal carcinomas (CRCs) progress through heterogeneous pathways. The aim of this study was to analyse whether or not the cytogenetic evolution of CRC is linked to tumour site, level of chromosomal imbalance and metastasis. METHOD: A set of therapy-naïve pT3 CRCs comprising 26 proximal and 49 distal pT3 CRCs was studied by combining immunohistochemistry of mismatch repair (MMR) proteins, microsatellite analyses and molecular karyotyping as well as clinical parameters. RESULTS: A MMR deficient/microsatellite-unstable (dMMR/MSI-H) status was associated with location of the primary tumour proximal to the splenic flexure, and dMMR/MSI-H tumours presented with significantly lower levels of chromosomal imbalances compared with MMR proficient/microsatellite-stable (pMMR/MSS) tumours. Oncogenetic tree modelling suggested two evolutionary clusters characterized by dMMR/MSI-H and chromosomal instability (CIN), respectively, for both proximal and distal CRCs. In CIN cases, +13q, -18q and +20q were predicted as preferentially early events, and -1p, -4 -and -5q as late events. Separate oncogenetic tree models of proximal and distal cases indicated similar early events independent of tumour site. However, in cases with high CIN defined by more than 10 copy number aberrations, loss of 17p occurred earlier in cytogenetic evolution than in cases showing low to moderate CIN. Differences in the oncogenetic trees were observed for CRCs with lymph node and distant metastasis. Loss of 8p was modelled as an early event in node-positive CRC, while +7p and +8q comprised early events in CRC with distant metastasis. CONCLUSION: CRCs characterized by CIN follow multiple, interconnected genetic pathways in line with the basic 'Vogelgram' concept proposed for the progression of CRC that places the accumulation of genetic changes at centre of tumour evolution. However, the timing of specific genetic events may favour metastatic potential.

Prognostic value of the micronucleus assay for clinical endpoints in neoadjuvant radiochemotherapy for rectal cancer.

BACKGROUND: The question whether lymphocyte radiosensitivity is representative of patients' response to radiotherapy (RT) remains unsolved. We analyzed lymphocyte cytogenetic damage in patients who were homogeneously treated with preoperative radiochemotherapy (RCT) for rectal cancer within clinical trials. We tested for interindividual variation and consistent radiosensitivity after in-vivo and in-vitro irradiation, analyzed the effect of patients' and RCT characteristics on cytogenetic damage, and tested for correlations with patients' outcome in terms of tumor response, survival and treatment-related toxicity. METHODS: The cytokinesis-block micronucleus cytome (CBMNcyt) assay was performed on the peripheral blood lymphocytes (PBLCs) of 134 patients obtained before, during, at the end of RCT, and during the 2-year follow-up. A subset of PBLCs obtained before RCT was irradiated in-vitro with 3 Gy. RCT included 50.4 Gy of pelvic RT with 5-fluorouracil (5-FU) alone (n = 78) or 5-FU plus oxaliplatin (n = 56). The analyzed variables included patients' age, gender, RT characteristics (planning target volume size [PTV size], RT technique), and chemotherapy characteristics (5-FU plasma levels, addition of oxaliplatin). Outcome was analyzed as tumor regression, patient survival, and acute and late toxicity. RESULTS: Cytogenetic damage increased significantly with the radiation dose and varied substantially between individuals. Women were more sensitive than men; no significant age-dependent differences were observed. There was a significant correlation between the cytogenetic damage after in-vitro irradiation and in-vivo RCT. We found a significant effect of the PTV size on the yields of cytogenetic damage after RCT, while the RT technique had no effect. Neither the addition of oxaliplatin nor the 5-FU levels influenced cytogenetic damage. We found no correlation between patient outcome and the cytogenetic damage. CONCLUSIONS: We found consistent cytogenetic damage in lymphocytes after in-vivo RCT and in-vitro irradiation. Gender was confirmed as a well-known, and the PTV size was identified as a less well-known influencing variable on lymphocyte cytogenetic damage after partial-body irradiation. A consistent level of cytogenetic damage after in-vivo and in-vitro irradiation may indicate the importance of genetic factors for individual radiosensitivity. However, we found no evidence that in-vivo or in-vitro irradiation-induced cytogenetic damage is an adequate biomarker for the response to RCT in rectal cancer patients.

Quality of life in rectal cancer patients with or without oxaliplatin in the randomised CAO/ARO/AIO-04 phase 3 trial.

BACKGROUND: The CAO/ARO/AIO trial has shown that oxaliplatin added to preoperative chemoradiotherapy and postoperative chemotherapy significantly improved disease-free survival in locally advanced rectal cancer (LARC). Here, we present a post-hoc analysis of quality of life (QoL) in disease-free patients. PATIENTS AND METHODS: Between 2006 and 2010, 1236 patients with LARC were randomly assigned either to preoperative chemoradiotherapy followed by total mesorectal excision and postoperative chemotherapy (N = 623) or combined with oxaliplatin (N = 613). QoL questionnaires (EORTC QLQ-C30, colorectal module CR38) were completed at baseline, after postoperative chemotherapy and during follow-up. Analysis was performed according intent-to-treat. RESULTS: Available questionnaires (baseline) were 82% (N = 512) in the control and 84% (N = 513) in the investigational group. Response rates were 49% (533 of 1086) at 1 year and 43% (403 of 928) at 3 years. Global health status (GHS) for disease-free patients was stable in both groups (range 0-100). At baseline: standard arm 62.0 (mean, SD 21.6; N = 491) versus oxaliplatin arm 63.2 (mean, SD 22; N = 503); at 3 years: 69.4 (SD 19.3; N = 187) versus 65.4 (SD 22.2; N = 202). After treatment and at 3 years, no significant differences (≥10 points) between groups were found in QoL subscales. Disease-free patients experiencing neurotoxic side-effects (grade 1-4) showed reduced GHS at 3 years versus patients without neurotoxicity (mean 59.2 versus 69.3; P < 0.001), while grade 3-4 rate was low. CONCLUSION: The addition of oxaliplatin was not associated with worse overall QoL. This information is of interest to patients in many ongoing rectal cancer trials. TRIAL REGISTRATION INFORMATION: NCT00349076.

Combined targeting of HER-2 and HER-3 represents a promising therapeutic strategy in colorectal cancer.

BACKGROUND: Abrogation of growth factor-dependent signaling represents an effective therapeutic strategy for patients with colorectal cancer (CRC). Here we evaluated the effectiveness of targeting the epidermal growth factor (EGF) receptors HER-2 and HER-3 in the three cell lines LS513, LS1034 and SW837. METHODS: Treatment with HER-2-specific antibodies trastuzumab and pertuzumab resulted in a mild reduction of cellular viability. In contrast, the antibody-drug conjugate T-DM1 mediated a strong and dose-dependent decrease of viability and Akt phosphorylation. RESULTS: The most striking effects were observed with the dual tyrosine kinase inhibitor lapatinib, and the Pan-ErbB inhibitor afatinib. Selectively, the effect of EGF receptor inhibition was augmented by a combination with 5-fluorouracil and oxaliplatin. Finally, high expression of HER-3 was detected in 121 of 172 locally advanced rectal cancers (70.3%). In conclusion, inhibition of EGF receptors effectively blocks downstream signaling and significantly impairs viability of CRC cells. However, the effectiveness of receptor inhibition highly depends on the inhibitors' mode of action, as targeting HER-2 alone is not sufficient. CONCLUSION: Since HER-2 and HER-3 are expressed in a relevant number of patients, targeting both receptors may represent a promising therapeutic strategy for CRC.

Leukocytosis and neutrophilia as independent prognostic immunological biomarkers for clinical outcome in the CAO/ARO/AIO-04 randomized phase 3 rectal cancer trial.

Peripheral blood leukocytosis and neutrophilia reflect cancer inflammation and have been proposed as prognostic immunological biomarkers in various malignancies. However, previous studies were limited by their retrospective nature and small patient numbers. Baseline peripheral blood leukocytes, neutrophils, hemoglobin, platelets, lactate dehydrogenase and carcinoembryonic antigen (CEA) were correlated with clinicopathologic characteristics, and clinical outcome in 1236 patients with rectal cancer treated with 5-FU-based preoperative chemoradiotherapy (CRT) alone or with oxaliplatin followed by surgery and adjuvant chemotherapy within the CAO/ARO/AIO-04 randomized phase 3 trial. Multivariable analyses were performed using Cox regression models. After a median follow-up of 50 months, baseline leukocytosis remained an independent adverse prognostic factor for disease-free survival (DFS; HR 1.457; 95% CI 1.163-1.825; p = 0.001), distant metastasis (HR 1.696; 95% CI 1.266-2.273; p < 0.001) and overall survival (OS; HR 1.716; 95% CI 1.264-2.329; p = 0.001) in multivariable analysis. Similar significant findings were observed for neutrophilia and high CEA levels. Conversely, treatment-induced leukopenia correlated with favorable DFS (p = 0.037), distant metastasis (p = 0.028) and OS (p = 0.012). Intriguingly, addition of oxaliplatin to 5-FU CRT resulted in a significant DFS improvement only in patients with neutrophilia and leukocytosis (p = 0.028 and p = 0.002). Our findings have important clinical implications and provide high-level evidence on the adverse prognostic role of leukocytes and neutrophils, and the impact of chemotherapy in the context of these biomarkers. These data could help guide patient stratification and should be further validated within prospective studies.

Can clinicopathological parameters predict for lymph node metastases in ypT0-2 rectal carcinoma? Results of the CAO/ARO/AIO-94 and CAO/ARO/AIO-04 phase 3 trials.

BACKGROUND: The advent of less radical surgical approaches has generated concern about leaving locoregional lymph node metastases (LNM) unresected that could lead to adverse outcome. We examined the prognostic role of clinicopathological factors for ypN-positivity in patients with ypT0-2 rectal carcinoma treated within the CAO/ARO/AIO-94 and CAO/ARO/AIO-04 randomized phase 3 trials. METHODS: The correlation of clinicopathological factors with ypN-status (ypN0 vs ypN1/2) was examined in n = 776 patients with ypT0-2 rectal carcinoma after preoperative CRT and total mesorectal excision surgery using Pearson's Chi-squared test for categorical variables and Kruskal-Wallis' test for continuous variables. Multivariable analysis was performed using binary logistic regression to identify independent prognosticators for ypN-positivity. RESULTS: Residual LNM (ypN+) were found in 6%, 20.8% and 21.4% of patients with ypT0, ypT1 and ypT2 carcinomas, respectively. Independent prognosticators for LNM were advanced ypT category (p = 0.002) and lymphatic invasion (p = 0.020). In a separate multivariable analysis performed upon exclusion of ypT-category due to multicollinearity with residual tumor diameter (RTD), lymphatic invasion (p = 0.015) and RTD ≥10 mm (p = 0.005) demonstrated strong correlation with LNM. CONCLUSION: Advanced ypT-stage, lymphatic invasion and RTD ≥10 mm were prognostic factors for LNM in patients ypT0-2 rectal carcinoma treated with CRT and surgery within both phase 3 trials. The high incidence of LNM in the ypT1-2 group needs to be taken into consideration in the context of oncological safety and indicate that LE should be advocated with great caution in this patient subgroup. The prognostic pathological factor identified here could help guide decision of LE vs TME after standard CRT.

Association of Plane of Total Mesorectal Excision With Prognosis of Rectal Cancer: Secondary Analysis of the CAO/ARO/AIO-04 Phase 3 Randomized Clinical Trial.

Importance: Previous retrospective studies have shown that surgical quality affects local control in rectal cancer.. Objective: In this secondary end point analysis, we evaluated the prognostic effect of the total mesorectal excision (TME) plane in the CAO/ARO/AIO-04 phase 3 randomized clinical trial. Design, Setting, and Participants: The CAO/ARO/AIO-04 trial enrolled 1236 patients with cT3-4 and/or node-positive rectal adenocarcinoma from 88 centers in Germany between July 25, 2006, and February 26, 2010. Interventions: Patients were randomized to receive treatment with standard fluorouracil-based preoperative chemoradiotherapy (CRT) alone (control arm) or oxaliplatin (experimental arm) followed by TME and adjuvant chemotherapy. Main Outcomes and Measures: The TME quality (mesorectal, intramesorectal, and muscularis propria plane) was prospectively assessed in 1152 operation specimens. An assessment was performed independently by pathologists and surgeons. The results were correlated with clinicopathologic data and the clinical outcome was tested, including multivariable analysis with the Cox regression model. Results: Of 1152 German Caucasian participants, 332 (28.8) were women and the mean age was 63 years. The plane of TME was mesorectal in 930 patients (80.7%), intramesorectal in 169 (14.7%), and muscularis propria in 53 (4.6%). In a univariable analysis, the TME plane was significantly associated with 3-year disease-free survival (mesorectal vs intramesorectal vs muscularis propria, 95% CI, 73.1-78.8 vs 61.6-76.0 vs 55.6-81.3, respectively; P = .01), cumulative incidence of local and distant recurrences (mesorectal vs intramesorectal vs muscularis propria, 95% CI, 2.0-4.5 vs 1.2-8.1 vs 2.5-20.5, respectively; P < .001; and mesorectal vs intramesorectal vs muscularis propria, 95% CI, 17.0-22.4 vs 18.3-32.0 vs 14.2-39.0, respectively; P = .03, respectively), and overall survival (mesorectal vs intramesorectal vs muscularis propria, 95% CI, 88.3-92.3 vs 79.7-91.0 vs 81.6-98.7, respectively; P = .02). In contrast to the pathologist-based evaluation, the assessment of TME plane by the operating surgeon failed to demonstrate prognostic significance for any of these clinical end points. In a multivariable analysis, the plane of surgery (mesorectal vs muscularis propria TME) constituted an independent factor for local recurrence (P = .002). Conclusions and Relevance: This phase 3 randomized clinical trial confirms the long-term clinical effect of TME plane quality on local recurrence, as initially reported in the MRC CR07 study. The data highlight the key role of pathologists and surgeons in the multidisciplinary management of rectal cancer. Trial Registration: ClinicalTrials.gov Identifier: NCT00349076.

Tumor Regression Grading After Preoperative Chemoradiotherapy as a Prognostic Factor and Individual-Level Surrogate for Disease-Free Survival in Rectal Cancer.

Background: We investigated tumor regression grading (TRG) as a prognostic marker and individual-level surrogate for disease-free survival (DFS) in patients with rectal carcinoma treated within the Chirurgische Arbeitsgemeinschaft fur Onkologie/Arbeitsgemeinschaft Radiologische Onkologie/Arbeitsgemeinschaft Internistische Onkologie (CAO/ARO/AIO)-04 randomized trial. Methods: TRG was recorded prospectively using the Dworak classification in 1179 patients after preoperative fluorouracil-based chemoradiotherapy (CRT) with or without oxaliplatin. Multivariable analysis was performed using Cox regression models adjusted for treatment arm, resection status, and pathologic stage. Individual-level surrogacy of TRG for DFS was examined using the four Prentice criteria (PC1-4). All statistical tests were two-sided. Results: With a median follow-up of 50 months, the addition of oxaliplatin to fluorouracil-based CRT led to statistically significantly improved three-year DFS (75.9%, 95% CI = 72.3 to 79.5, vs 71.3%, 95% CI = 67.6 to 74.9, P = .04, PC 1) and a shift toward more advanced TRG groups ( P < .001, PC 2) compared with CRT with fluorouracil alone. The three-year DFS was 64.6% (95% CI = 57.3 to 71.9), 77.6% (95% CI = 74.5 to 80.7), and 92.3% (95% CI = 88.4 to 96.2) for TRG 0 + 1 (poor regression), TRG 2 + 3 (intermediate regression), and TRG 4 (complete regression), respectively ( P < .001, PC 3). TRG constituted an independent prognostic factor for DFS (TRG 2 + 3 vs TRG 0 + 1, HR = 0.68, 95% CI = 0.51 to 0.90, P = .007). Due to multicollinearity, TRG 4 and pathologic stage could not be tested within the same model. The treatment effect on DFS was captured by TRG, satisfying individual-level PC4. Conclusions: Higher TRG after preoperative CRT predicted a favorable long-term outcome. At the individual patient level, TRG was a surrogate marker for DFS. Further phase III trials are needed to validate TRG as a surrogate at trial level.

CONKO-005: Adjuvant Chemotherapy With Gemcitabine Plus Erlotinib Versus Gemcitabine Alone in Patients After R0 Resection of Pancreatic Cancer: A Multicenter Randomized Phase III Trial.

Purpose Gemcitabine is standard of care in the adjuvant treatment of resectable pancreatic ductal adenocarcinoma (PDAC). The epidermal growth factor receptor tyrosine kinase inhibitor erlotinib in combination with gemcitabine has shown efficacy in the treatment of advanced PDAC and was considered to improve survival in patients with primarily resectable PDAC after R0 resection. Patients and Methods In an open-label, multicenter trial, patients were randomly assigned to one of two study arms: gemcitabine 1,000 mg/m2 days 1, 8, 15, every 4 weeks plus erlotinib 100 mg once per day (GemErlo) or gemcitabine (Gem) alone for six cycles. The primary end point of the study was to improve disease-free survival (DFS) from 14 to 18 months by adding erlotinib to gemcitabine. Results In all, 436 patients were randomly assigned at 57 study centers between April 2008 and July 2013. A total of 361 instances (83%) of disease recurrence were observed after a median follow-up of 54 months. Median treatment duration was 22 weeks in both arms. There was no difference in median DFS (GemErlo 11.4 months; Gem 11.4 months) or median overall survival (GemErlo 24.5 months; Gem 26.5 months). There was a trend toward long-term survival in favor of GemErlo (estimated survival after 1, 2, and 5 years for GemErlo was 77%, 53%, and 25% v 79%, 54%, and 20% for Gem, respectively). The occurrence or the grade of rash was not associated with a better survival in the GemErlo arm. Conclusion To the best of our knowledge, CONKO-005 is the first study to investigate the combination of chemotherapy and a targeted therapy in the adjuvant treatment of PDAC. GemErlo for 24 weeks did not improve DFS or overall survival over Gem.

The Prognostic Value of Tyrosine Kinase SRC Expression in Locally Advanced Rectal Cancer.

The cellular sarcoma gene (SRC) is a proto-oncogene encoding for a tyrosine kinase. SRC expression was determined in locally advanced rectal adenocarcinoma tissue from pretreatment biopsies and resection specimens. The expression level was correlated with clinicopathological parameters to evaluate the predictive and prognostic capacity. For this monocentric analysis 186 patients with locally advanced rectal cancer (median: 63.7 years; 130 men (69.9%), 56 women (30.1%)) were included. Patients with a carcinoma of the upper third of the rectum were treated with primary tumor resection (n=27; 14.5%). All other patients received a preoperative chemoradiotherapy (CRT) with 50.4 Gy and concomitant 5-fluorouracil (5-FU) or 5-FU+oxaliplatin followed by postoperative chemotherapy with 5-FU or 5-FU+oxaliplatin. SRC expression was determined with immunohistochemical staining from pretreatment biopsies (n=152) and residual tumor tissue from the resection specimens (n=163). The results were correlated with clinicopathological parameters and long-term follow-up. The expression of SRC was determined in pretherapeutic biopsies (mean H-Score: 229) and resection specimens (mean H-Score: 254). High SRC expression in pretherapeutic tumor samples significantly correlated with a negative postoperative nodal status (p=0.005). Furthermore an increased protein expression in residual tumor tissue was associated with fewer distant metastases (p=0.04). The overexpression of SRC in pretreatment tumor biopsies showed also a trend for a longer cancer-specific survival (CSS; p=0.05) and fewer local relapses (p=0.06) during long-term follow-up. High SRC expression in rectal cancer seems to be associated with a better long-term outcome. This finding could help in the future to stratify patients for a recurrence risk adapted postoperative treatment.

Repeated adjuvant anti-CEA radioimmunotherapy after resection of colorectal liver metastases: Safety, feasibility, and long-term efficacy results of a prospective phase 2 study.

BACKGROUND: In previous work, a single administration of anticarcinoembryonic antigen (anti-CEA) 131 I-labetuzumab radioimmunotherapy (RIT) after complete resection of colorectal liver metastases was well tolerated and significantly improved survival compared with controls. In the current phase 2 trial, the authors studied repeated RIT in the same setting, examining safety, feasibility, and efficacy. METHODS: Sixty-three patients (median age, 64.5 years) received RIT at 40 to 50 millicuries/m2 per dose. Before the receipt of RIT, restaging was performed with computed tomography/magnetic resonance imaging and 18 F-fluorodeoxyglucose-positron emission to confirm that patients were "truly adjuvant." Patients who had elevated serum CEA levels or radiographically inconclusive new lesions were classified as "possibly nonadjuvant," but they also received RIT. Time to progression (TTP), overall survival (OS), and cause-specific survival (CSS) were calculated. The median follow-up was 54 months. RESULTS: After the first course of RIT, 14 of 63 patients experienced National Cancer Institute Common Toxicity Criteria grade 4 hematotoxicity; 19 patients did not receive the second course of RIT because of impaired performance status (N = 5) or relapse (N = 14). After the second course of RIT, 9 of 44 patients experienced National Cancer Institute Common Toxicity Criteria grade 4 hematotoxicity. Five patients developed myelodysplastic syndrome (MDS) from 22 to 55 months after their last RIT. The median TTP, OS, and CSS for all patients were 16, 55, and 60 months, respectively. The "truly adjuvant" patients (N = 39) had an improved median TTP (not reached vs 6.1 months; hazard ratio, 0.12; P < .001), OS (75.6 vs 33.4 months; hazard ratio, 0.44; P = .014), and CSS (not reached vs 41.4 months; hazard ratio,0.42; P = .014) compared with "possibly nonadjuvant" patients (N = 24). CONCLUSIONS: Repeated RIT with 131 I-labetuzumab is feasible but is associated with hematotoxicity. Survival is very encouraging, especially for "truly adjuvant" patients. However, the maximum safe dose of 131 I-labetuzumab is a single administration of 50 millicuries/m2 . Cancer 2017;123:638-649. © 2016 American Cancer Society.

Neoadjuvant Therapy in Rectal Cancer - Biobanking of Preoperative Tumor Biopsies.

Translational research relies on high-quality biospecimens. In patients with rectal cancer treated preoperatively with radiochemotherapy tissue based analyses are challenging. To assess quality challenges we analyzed tissue samples taken over the last years in a multicenter setting. We retrospectively evaluated overall 197 patients of the CAO/ARO/AIO-94- and 04-trial with locally advanced rectal cancer that were biopsied preoperatively at the University Medical Center Goettingen as well as in 10 cooperating hospitals in Germany. The cellular content of tumor, mucosa, stroma, necrosis and the amount of isolated DNA and RNA as well as the RNA integrity number (RIN) as quality parameters were evaluated. A high RNA yield (p = 2.75e-07) and the content of tumor (p = 0.004) is significantly associated to high RIN-values, whereas a high content of mucosa (p = 0.07) shows a trend and a high amount of necrosis (p = 0.01) is significantly associated with RNA of poor quality. Correlating biopsies from Goettingen and the cooperating centers showed comparable tumor content results. By taking small sized biopsies we could assess a clear correlation between a good RNA quality and a high amount of RNA and tumor cells. These results also indicate that specimens collected at different centers are of comparable quality.

Stage-Dependent Frequency of Lymph Node Metastases in Patients With Rectal Carcinoma After Preoperative Chemoradiation: Results from the CAO/ARO/AIO-94 Trial and From a Comparative Prospective Evaluation With Extensive Pathological Workup.

BACKGROUND: For patients with ycT1/2 rectal carcinomas after neoadjuvant chemoradiotherapy, local excision instead of radical surgery has increasingly been discussed as a way to avoid postoperative morbidity associated with radical surgery. OBJECTIVE: The purpose of this study was to determine the incidence of lymph node metastases in total mesorectal excision specimens with ypT0, ypT1/2, and ypT3/4 rectal cancers. DESIGN: This is a prospective and retrospective cohort study. SETTINGS: This study was conducted in tertiary referral hospitals that are part of the German Rectal Cancer Study Group. PATIENTS: A total of 479 patients with stage II and III rectal cancers treated within phase III trials of the German Rectal Cancer Study Group were evaluated. Specimens from 81 patients treated in the Working Group of Surgical Oncology/Working Group of Radiation Oncology/Working Group of Medical Oncology of the Germany Cancer Society (CAO/ARO/AIO-04) trial were prospectively studied with extensive microscopic screening of the entire mesorectum. The frequency and localization of nodal metastases were specified and compared with those of 398 patients having received neoadjuvant chemoradiation within the CAO/ARO/AIO-94 trial. MAIN OUTCOME MEASURES: Frequency and localization of mesorectal lymph node metastases in patients with ypT0, ypT1/2, or ypT3/4 cancer were measured. RESULTS: A mean number of 28.0 ± 13.7 nodes were detected per specimen within the prospective group. A total of 25% of patients in the ypT1/2 group had nodal metastases compared with 40% in the ypT3/4 group. Patients with node-positive ypT1/2 had a mean number of 2.2 metastases, and 55% of these metastases were located far from the primary lesion in the proximal mesorectum. Within the CAO/ARO/AIO-94 cohort (n = 398), 19% of patients with ypT1/2 (ypT1 = 22%; ypT2 = 18%) had ypN+ status compared with 43% with ypT3/4 cancers (ypT3 = 40%; ypT4 = 73%). LIMITATIONS: Low numbers of patients with ypT0 limited the evaluation of nodal metastases in pathologic complete responders. CONCLUSIONS: Even in good responders (ypT1/2), >20% of rectal carcinomas still harbored residual lymph node metastases. Local excision for patients with ycT1/2 rectal cancers would, thus, miss metastases in a considerable percentage and might involve the risk of significant undertreatment in a number of patients.

ß-catenin-independent WNT signaling and Ki67 in contrast to the estrogen receptor status are prognostic and associated with poor prognosis in breast cancer liver metastases.

Liver metastasis development in breast cancer patients is common and confers a poor prognosis. So far, the prognostic significance of surgical resection and clinical relevance of biomarker analysis in metastatic tissue have barely been investigated. We previously demonstrated an impact of WNT signaling in breast cancer brain metastasis. This study aimed to investigate the value of established prognostic markers and WNT signaling components in liver metastases. Overall N = 34 breast cancer liver metastases (with matched primaries in 19/34 cases) were included in this retrospective study. Primaries and metastatic samples were analyzed for their expression of the estrogen (ER) and progesterone receptor, HER-2, Ki67, and various WNT signaling-components by immunohistochemistry. Furthermore, ß-catenin-dependent and -independent WNT scores were generated and analyzed for their prognostic value. Additionally, the influence of the alternative WNT receptor ROR on signaling and invasiveness was analyzed in vitro. ER positivity (HR 0.09, 95 % CI 0.01-0.56) and high Ki67 (HR 3.68, 95 % CI 1.12-12.06) in the primaries had prognostic impact. However, only Ki67 remained prognostic in the metastatic tissue (HR 2.46, 95 % CI 1.11-5.44). Additionally, the ß-catenin-independent WNT score correlated with reduced overall survival only in the metastasized situation (HR 2.19, 95 % CI 1.02-4.69, p = 0.0391). This is in line with the in vitro results of the alternative WNT receptors ROR1 and ROR2, which foster invasion. In breast cancer, the value of prognostic markers established in primary tumors cannot directly be translated to metastases. Our results revealed ß-catenin-independent WNT signaling to be associated with poor prognosis in patients with breast cancer liver metastasis.

Oxaliplatin added to fluorouracil-based preoperative chemoradiotherapy and postoperative chemotherapy of locally advanced rectal cancer (the German CAO/ARO/AIO-04 study): final results of the multicentre, open-label, randomised, phase 3 trial.

BACKGROUND: Preoperative chemoradiotherapy with infusional fluorouracil, total mesorectal excision surgery, and postoperative chemotherapy with fluorouracil was established by the German CAO/ARO/AIO-94 trial as a standard combined modality treatment for locally advanced rectal cancer. Here we compare the previously established regimen with an investigational regimen in which oxaliplatin was added to both preoperative chemoradiotherapy and postoperative chemotherapy. METHODS: In this multicentre, open-label, randomised, phase 3 study we randomly assigned patients with rectal adenocarcinoma, clinically staged as cT3-4 or any node-positive disease, to two groups: a control group receiving standard fluorouracil-based combined modality treatment, consisting of preoperative radiotherapy of 50·4 Gy in 28 fractions plus infusional fluorouracil (1000 mg/m(2) on days 1-5 and 29-33), followed by surgery and four cycles of bolus fluorouracil (500 mg/m(2) on days 1-5 and 29); or to an investigational group receiving preoperative radiotherapy of 50·4 Gy in 28 fractions plus infusional fluorouracil (250 mg/m(2) on days 1-14 and 22-35) and oxaliplatin (50 mg/m(2) on days 1, 8, 22, and 29), followed by surgery and eight cycles of oxaliplatin (100 mg/m(2) on days 1 and 15), leucovorin (400 mg/m(2) on days 1 and 15), and infusional fluorouracil (2400 mg/m(2) on days 1-2 and 15-16). Randomisation was done with computer-generated block-randomisation codes stratified by centre, clinical T category (cT1-3 vs cT4), and clinical N category (cN0 vs cN1-2) without masking. The primary endpoint was disease-free survival, defined as the time between randomisation and non-radical surgery of the primary tumour (R2 resection), locoregional recurrence after R0/1 resection, metastatic disease or progression, or death from any cause, whichever occurred first. Survival and cumulative incidence of recurrence analyses followed the intention-to-treat principle; toxicity analyses included all patients treated. Enrolment of patients in this trial is completed and follow-up is ongoing. This study is registered with ClinicalTrials.gov, number NCT00349076. FINDINGS: Of the 1265 patients initially enrolled, 1236 were assessable (613 in the investigational group and 623 in the control group). With a median follow-up of 50 months (IQR 38-61), disease-free survival at 3 years was 75·9% (95% CI 72·4-79·5) in the investigational group and 71·2% (95% CI 67·6-74·9) in the control group (hazard ratio [HR] 0·79, 95% CI 0·64-0·98; p=0·03). Preoperative grade 3-4 toxic effects occurred in 144 (24%) of 607 patients who actually received fluorouracil and oxaliplatin during chemoradiotherapy and in 128 (20%) of 625 patients who actually received fluorouracil chemoradiotherapy. Of 445 patients who actually received adjuvant fluorouracil and leucovorin and oxaliplatin, 158 (36%) had grade 3-4 toxic effects, as did 170 (36%) of 470 patients who actually received adjuvant fluorouracil. Late grade 3-4 adverse events in patients who received protocol-specified preoperative and postoperative treatment occurred in 112 (25%) of 445 patients in the investigational group, and in 100 (21%) of 470 patients in the control group. INTERPRETATION: Adding oxaliplatin to fluorouracil-based neoadjuvant chemoradiotherapy and adjuvant chemotherapy (at the doses and intensities used in this trial) significantly improved disease-free survival of patients with clinically staged cT3-4 or cN1-2 rectal cancer compared with our former fluorouracil-based combined modality regimen (based on CAO/ARO/AIO-94). The regimen established by CAO/ARO/AIO-04 can be deemed a new treatment option for patients with locally advanced rectal cancer. FUNDING: German Cancer Aid (Deutsche Krebshilfe).

EGFR and ß1-integrin targeting differentially affect colorectal carcinoma cell radiosensitivity and invasion.

BACKGROUND AND PURPOSE: Simultaneous targeting of ß1 integrin receptor and epidermal growth factor receptor (EGFR) showed higher level of radiosensitization in head and neck cancers than monotherapies. As EGFR inhibition is similarly performed in colorectal cancer (CRC), we investigated the radiosensitizing and anti-invasive potential of ß1-integrin/EGFR inhibition in CRC cell lines grown in more physiological three-dimensional (3D) matrix-based cell cultures. MATERIALS AND METHODS: DLD-1 and HT-29 cells were used for 3D-colony formation, invasion and proliferation assays and Western blotting. ß1 integrin, focal adhesion kinase and EGFR were inhibited by AIIB2, TAE226 and Cetuximab, respectively. KRAS and BRAF knockdown were accomplished using small-interfering RNA technology. Single doses of X-rays ranged from 2Gy to 6Gy and 5-fluorouracil (5-FU) concentration was 10µM. RESULTS: Neither ß1-integrin/EGFR inhibition nor KRAS or BRAF depletion nor 5-FU significantly modified CRC cell radiosensitivity. Cetuximab, AIIB2 and Cetuximab/AIIB2 differentially modulated MAPK, JNK and AKT phosphorylation. AIIB2 and TAE226 significantly decreased cell invasion. CONCLUSIONS: Our data show inefficiency of Cetuximab and AIIB2 on top of radiochemotherapy. The functions of KRAS and BRAF in therapy resistance remain unanswered and warrant further preclinical molecular-driven investigations. One promising approach might be ß1 integrin targeting for reducing metastatic CRC cell spread.

HER-2 and HER-3 expression in liver metastases of patients with colorectal cancer.

OBJECTIVE: In this study, we evaluate the frequency of HER-2 and HER-3 expression in liver metastases from patients with colorectal cancer (CRLM). We analyzed the potential of HER-2 and HER-3 as therapeutic targets and evaluated their prognostic value. PATIENTS AND METHODS: Overall 208 patients with CRLM were enrolled. HER-2 and HER-3 expression were determined in metastatic tissue of diagnostic punch biopsies (n = 29) or resection specimens (n = 179). The results of immunohistochemistry (IHC) scoring and In-situ-hybridization (ISH)-amplification were correlated with clinical parameters and for the 179 resected patients with cancer-specific (CSS) and overall survival (OS). The mean follow-up time was 56.7 months. RESULTS: Positivity of HER-2 status (IHC score 2+/ISH+ and IHC 3+) was found in 8.2% of CRLM. High expression of HER-3 (IHC score 2+ and IHC 3+) was detected in 75.0% of liver metastases. CSS after liver surgery was determined and was independent from the HER-2 status (p = 0.963); however HER-3 was prognostic with a favorable course for patients showing an overexpression of HER-3 (p = 0.037). CONCLUSIONS: HER-2 overexpression occurs in only 8% of patients with CRLM but with 75% of cases HER-3 is frequently overexpressed in CRLM. Therefore, HER-2 and particularly HER-3 could serve as novel targets to be addressed within multimodal treatment approaches.

Comprehensive lymph node morphometry in rectal cancer using acetone compression.

AIMS: Acetone compression (AC) is an elution compression technique for the comprehensive pathological examination of fatty tissue. Here AC is combined with digital morphometry to evaluate the impact of preoperative (neoadjuvant) chemoradiotherapy (neoCRT) on lymph node (LN) numbers and morphology in locally advanced rectal cancer. AC is compared with complete embedding of the mesorectal fat (whole mesorectal embedding (WME)) to exclude artificial alterations and to the standard technique, manual dissectioning (MD). METHODS: 320 rectal cancer specimens were subjected to LN morphometry. Neoadjuvant CRT was applied in 204 specimens. LNs were prepared either with AC (n=138), WME (n=51) or MD (n=131). 8523 LNs were assessed including 530 nodes with metastases. RESULTS: LN prepared by AC and WME showed similar morphologies. AC revealed reduced LN sizes in neoCRT specimens compared with primary resection (2.2; 2.4 mm, p=0.049) while the LN number was comparable (27; 30/specimen). AC yielded 28 LN/specimen on average, MD yielded 22 LN (p<0.001). In neoCRT specimens, MD yielded less LN compared with primary resection (19; 25). MD detected less small LN (<2 mm; MD: 25%; AC: 56%) while 24 of the 135 LN metastases found by AC were ≤2 mm in diameter. CONCLUSIONS: AC does not alter LN morphology and is especially suited to retrieve small LN after neoadjuvant CRT of rectal cancer. Neoadjuvant multimodality treatment caused reduced LN sizes while the LN numbers were not affected. When compared with MD, AC proved more reliable in the retrieval of LN from rectal cancer specimens after neoCRT.

Downstage migration after neoadjuvant chemoradiotherapy for rectal cancer: the reverse of the Will Rogers phenomenon?

Downstaging after neoadjuvant treatment is increasingly used as a prognostic factor and surrogate endpoint in clinical trials. However, in recent trials of neoadjuvant 5-fluorouracil-based chemoradiotherapy for rectal cancer, downstaging did not translate into a benefit with regard to either disease-free survival (DFS) or overall survival. By analyzing the 10-year outcome data of the German CAO/ARO/AIO-94 phase 3 trial, the authors demonstrated that significantly fewer patients had poor prognostic features (eg, ypT3-4, ypN1-2) after preoperative 5-fluorouracil-based chemoradiotherapy. Nevertheless, these patients with International Union for Cancer Control stage II disease were found to be at a higher risk of developing distant metastases and had poorer DFS compared with patients with corresponding TNM tumor (sub)groups in the postoperative treatment arm, whereas patients with International Union for Cancer Control stage III disease demonstrated a nonsignificant trend toward a worse outcome after preoperative treatment. Overall, DFS remained identical in both treatment arms. Thus, "downstage migration" after neoadjuvant treatment resembles the reverse of the Will Rogers phenomenon and therefore may not be a reliable endpoint for long-term outcomes.