Thomas Brunner

PURPOSE Total neoadjuvant therapy is a new paradigm for rectal cancer treatment. Optimal scheduling of preoperative chemoradiotherapy (CRT) and chemotherapy remains to be established. PATIENTS AND METHODS We conducted a multicenter, randomized, phase II trial using a pick-the-winner design on the basis of the hypothesis of an increased pathologic complete response (pCR) of 25% after total neoadjuvant therapy compared with standard 15% after preoperative CRT. Patients with stage II or III rectal cancer were assigned to group A for induction chemotherapy using three cycles of fluorouracil, leucovorin, and oxaliplatin before fluorouracil/oxaliplatin CRT (50.4 Gy) or to group B for consolidation chemotherapy after CRT. Secondary end points included toxicity, compliance, and surgical morbidity. RESULTS Of the 311 patients enrolled, 306 patients were evaluable (156 in group A and 150 in group B). CRT-related grade 3 or 4 toxicity was lower (37% v 27%) and compliance with CRT higher in group B (91%, 78%, and 76% v 97%, 87%, and 93% received full-dose radiotherapy, concomitant fluorouracil, and concomitant oxaliplatin in groups A and B, respectively); 92% versus 85% completed all induction/consolidation chemotherapy cycles, respectively. The longer interval between completion of CRT and surgery in group B (median 90 v 45 days in group A) did not increase surgical morbidity. A pCR in the intention-to-treat population was achieved in 17% in group A and in 25% in group B. Thus, only group B ( P < .001), but not group A ( P = .210), fulfilled the predefined statistical hypothesis. CONCLUSION Up-front CRT followed by chemotherapy resulted in better compliance with CRT but worse compliance with chemotherapy compared with group A. Long-term follow-up will assess whether improved pCR in group B translates to better oncologic outcome.

Combined radiochemotherapy is the currently used therapy for locally advanced pancreatic ductal adenocarcinoma (PDAC), but normal tissue toxicity limits its application. Here we test the hypothesis that inhibition of ATR (ATM-Rad3-related) could increase the sensitivity of the cancer cells to radiation or chemotherapy without affecting normal cells. We tested VE-822, an ATR inhibitor, for in vitro and in vivo radiosensitization. Chk1 phosphorylation was used to indicate ATR activity, γH2AX and 53BP1 foci as evidence of DNA damage and Rad51 foci for homologous recombination activity. Sensitivity to radiation (XRT) and gemcitabine was measured with clonogenic assays in vitro and tumor growth delay in vivo. Murine intestinal damage was evaluated after abdominal XRT. VE-822 inhibited ATR in vitro and in vivo. VE-822 decreased maintenance of cell-cycle checkpoints, increased persistent DNA damage and decreased homologous recombination in irradiated cancer cells. VE-822 decreased survival of pancreatic cancer cells but not normal cells in response to XRT or gemcitabine. VE-822 markedly prolonged growth delay of pancreatic cancer xenografts after XRT and gemcitabine-based chemoradiation without augmenting normal cell or tissue toxicity. These findings support ATR inhibition as a promising new approach to improve the therapeutic ration of radiochemotherapy for patients with PDAC.

BACKGROUND: Recent randomized controlled trials comparing neoadjuvant chemoradiation plus surgery or perioperative chemotherapy plus surgery with surgery alone showed significant survival benefits for combined modality treatment of patients with localized esophageal adenocarcinoma. However, head-to-head comparisons of neoadjuvant chemoradiation and perioperative chemotherapy applying contemporary treatment protocols are lacking. The present trial was initiated to obtain valid information whether neoadjuvant chemoradiation or perioperative chemotherapy yields better survival in the treatment of localized esophageal adenocarcinoma. METHODS/DESIGN: The ESOPEC trial is an investigator-initiated multicenter prospective randomized controlled two-arm trial, comparing the efficacy of neoadjuvant chemoradiation (CROSS protocol: 41.4Gy plus carboplatin/paclitaxel) followed by surgery versus perioperative chemotherapy and surgery (FLOT protocol: 5-FU/leucovorin/oxaliplatin/docetaxel) for the curative treatment of localized esophageal adenocarcinoma. Patients with cT1cN + cM0 and cT2-4acNxcM0 esophageal and junctional adenocarcinoma are eligible. The trial aims to include 438 participants who are centrally randomized to one of the two treatment groups in a 1:1 ratio stratified by N-stage and study site. The primary endpoint of the trial is overall survival assessed with a minimum follow-up of 36 months. Secondary objectives are progression-free survival, recurrence-free survival, site of failure, postoperative morbidity and mortality, duration of hospitalization as well as quality of life. DISCUSSION: The ESOPEC trial compares perioperative chemotherapy according to the FLOT protocol to neoadjuvant chemoradiation according to the CROSS protocol in multimodal treatment of non-metastasized recectable adenocarcinoma of the esophagus and the gastroesophageal junction. The goal of the trial is identify the superior protocol with regard to patient survival, treatment morbidity and quality of life. TRIAL REGISTRATION: NCT02509286 (July 22, 2015).

IMPORTANCE: Total neoadjuvant therapy has been increasingly adopted for multimodal rectal cancer treatment. The optimal sequence of chemoradiotherapy (CRT) and chemotherapy needs to be established. OBJECTIVE: To report the long-term results of the secondary end points prespecified in the Randomized Phase 2 Trial of Chemoradiotherapy Plus Induction or Consolidation Chemotherapy as Total Neoadjuvant Therapy (CAO/ARO/AIO-12 trial) for Locally Advanced Rectal Cancer. DESIGN, SETTING, AND PARTICIPANTS: This secondary analysis of a randomized clinical trial included 311 patients who were recruited from the accrued CAO/ARO/AIO-12 trial population from June 15, 2015, to January 31, 2018, from 18 centers in Germany. Patients with cT3-4 and/or node-positive rectal adenocarcinoma were included in the analysis. Data were analyzed from June 15, 2015, to January 31, 2018. The follow-up analysis was conducted between January 31, 2018, and November 30, 2020. INTERVENTIONS: Patients were randomly assigned to group A for 3 cycles of fluorouracil, leucovorin, and oxaliplatin before fluorouracil/oxaliplatin CRT (50.4 Gy), or to group B for CRT before chemotherapy. Total mesorectal excision was scheduled on day 123 after the start of total neoadjuvant therapy in both groups. MAIN OUTCOMES AND MEASURES: The end points assessed in this secondary analysis included long-term oncologic outcomes, chronic toxicity, patient-reported outcome measures for global health status (GHS) and quality of life (QoL), and the Wexner stool incontinence score. RESULTS: Of the 311 patients enrolled, 306 were evaluable, including 156 in group A (mean [SD] age, 60 [11] years; 106 men [68%]) and 150 in group B (mean [SD] age, 62 [10] years; 100 men [67%]). After a median follow-up of 43 months (range, 35-60 months), the 3-year disease-free survival was 73% in both groups (hazard ratio, 0.95; 95% CI, 0.63-1.45, P = .82); the 3-year cumulative incidence of locoregional recurrence (6% vs 5%, P = .67) and distant metastases (18% vs 16%, P = .52) were not significantly different. Chronic toxicity grade 3 to 4 occurred in 10 of 85 patients (11.8%) in group A and 8 of 66 patients (9.9%) in group B at 3 years. The GHS/QoL score decreased after total mesorectal excision but returned to pretreatment levels 1 year after randomization with no difference between the groups. Stool incontinence deteriorated 1 year after randomization in both groups and only improved slightly at 3 years, but never reached baseline levels. CONCLUSIONS AND RELEVANCE: This secondary analysis of a randomized clinical trial showed that CRT followed by chemotherapy resulted in higher pathological complete response without compromising disease-free survival, toxicity, QoL, or stool incontinence and is thus proposed as the preferred total neoadjuvant therapy sequence if organ preservation is a priority. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02363374.