The impact of sex on treatment and outcome in relation to histological subtype in patients with resectable gastric cancer: Results from the randomized CRITICS trial.

BACKGROUND AND OBJECTIVE: This study aims to investigate the impact of sex on outcome measures stratified by histological subtype in patients with resectable gastric cancer (GC). METHODS: A post-hoc analysis of the CRITICS-trial, in which patients with resectable GC were treated with perioperative therapy, was performed. Histopathological characteristics and survival were evaluated for males and females stratified for histological subtype (intestinal/diffuse). Additionally, therapy-related toxicity and compliance were compared. RESULTS: Data from 781 patients (523 males) were available for analyses. Female sex was associated with a distal tumor localization in intestinal (p = 0.014) and diffuse tumors (p < 0.001), and younger age in diffuse GC (p = 0.035). In diffuse GC, tumor-positive resection margins were also more common in females than males (21% vs. 10%; p = 0.020), specifically at the duodenal margin. During preoperative chemotherapy, severe toxicity occurred in 327 (63%) males and 184 (71%) females (p = 0.015). Notwithstanding this, relative dose intensities were not significantly different between sexes. CONCLUSIONS: Positive distal margin rates were higher in females with diffuse GC, predominantly at the duodenal site. Females also experience more toxicity, but this neither impacts dose intensities nor surgical resection rates. Clinicians should be aware of these different surgical outcomes when treating males and females with GC.

Triplet Chemotherapy with Cisplatin versus Oxaliplatin in the CRITICS Trial: Treatment Compliance, Toxicity, Outcomes and Quality of Life in Patients with Resectable Gastric Cancer.

(1) Background: Perioperative chemotherapy is the current standard treatment for patients with resectable gastric cancer. Based on studies in patients with metastatic gastric cancer, oxaliplatin has replaced cisplatin in the curative setting as well. However, evidence to prefer oxaliplatin over cisplatin in the curative setting is limited. (2) Methods: We compared patient-related and tumor-related outcomes for cisplatin versus oxaliplatin in patients with resectable gastric cancer treated with perioperative chemotherapy in the CRITICS trial. (3) Results: Preoperatively, 632 patients received cisplatin and 149 patients received oxaliplatin. Preoperative severe toxicity was encountered in 422 (67%) patients who received cisplatin versus 89 (60%) patients who received oxaliplatin (p = 0.105). Severe neuropathy was observed in 5 (1%) versus 6 (4%; p = 0.009) patients, respectively. Postoperative severe toxicity occurred in 109 (60%) versus 26 (51%) (p = 0.266) patients; severe neuropathy in 2 (1%) versus 2 (4%; p = 0.209) for patients who received cisplatin or oxaliplatin, respectively. Diarrhea impacted the quality of life more frequently in patients who received oxaliplatin compared to cisplatin. Complete or near-complete pathological response was achieved in 94 (21%) versus 16 (15%; p = 0.126) patients who received cisplatin or oxaliplatin, respectively. Overall survival was not significantly different in both groups (p = 0.300). (4) Conclusions: Both cisplatin and oxaliplatin are legitimate options as part of systemic treatment in patients with resectable gastric cancer.

Quality of Life Is Associated With Survival in Patients With Gastric Cancer: Results From the Randomized CRITICS Trial.

BACKGROUND: The evaluation of health-related quality of life (HRQoL) in clinical trials has become increasingly important because it addresses the impact of treatment from the patient's perspective. The primary aim of this study was to investigate the effect of postoperative chemotherapy and chemoradiotherapy (CRT) after neoadjuvant chemotherapy and surgery with extended (D2) lymphadenectomy on HRQoL in the CRITICS trial. Second, we investigated the potential prognostic value of pretreatment HRQoL on event-free survival (EFS) and overall survival (OS). PATIENTS AND METHODS: Patients in the CRITICS trial were asked to complete HRQoL questionnaires (EORTC Quality-of-Life Questionnaire-Core 30 and Quality-of-Life Questionnaire gastric cancer-specific module) at baseline, after preoperative chemotherapy, after surgery, after postoperative chemotherapy or CRT, and at 12 months follow-up. Patients with at least 1 evaluable questionnaire (645 of 788 randomized patients) were included in the HRQoL analyses. The predefined endpoints included dysphagia, pain, physical functioning, fatigue, and Quality-of-Life Questionnaire-Core 30 summary score. Linear mixed modeling was used to assess differences over time and at each time point. Associations of baseline HRQoL with EFS and OS were investigated using multivariate Cox proportional hazards analyses. RESULTS: At completion of postoperative chemo(radio)therapy, the chemotherapy group had significantly better physical functioning (P=.02; Cohen's effect size = 0.42) and less dysphagia (P=.01; Cohen's effect size = 0.38) compared with the CRT group. At baseline, worse social functioning (hazard ratio [HR], 2.20; 95% CI, 1.36-3.55; P=.001), nausea (HR, 1.89; 95% CI, 1.39-2.56; P<.001), worse WHO performance status (HR, 1.55; 95% CI, 1.13-2.13; P=.007), and histologic subtype (diffuse vs intestinal: HR, 1.94; 95% CI, 1.42-2.67; P<.001; mixed vs intestinal: HR, 2.35; 95% CI, 1.35-4.12; P=.003) were significantly associated with worse EFS and OS. CONCLUSIONS: In the CRITICS trial, the chemotherapy group had significantly better physical functioning and less dysphagia after postoperative treatment. HRQoL scales at baseline were significantly associated with EFS and OS.

Prognostic value of tumor markers and ctDNA in patients with resectable gastric cancer receiving perioperative treatment: results from the CRITICS trial.

AIM: To evaluate the prognostic value of tumor markers in a European cohort of patients with resectable gastric cancer. METHODS: We performed a post hoc analysis of the CRITICS trial, in which 788 patients received perioperative therapy. Association between survival and pretreatment CEA, CA 19-9, alkaline phosphatase, neutrophils, hemoglobin and lactate dehydrogenase were explored in uni- and multivariable Cox regression analyses. Likelihoods to receive potentially curative surgery were investigated for patients without elevated tumor markers versus one of the tumor markers elevated versus both tumor markers elevated. The association between tumor markers and the presence of circulating tumor DNA (ctDNA) was explored in 50 patients with available ctDNA data. RESULTS: In multivariable analysis, in which we corrected for allocated treatment and other baseline characteristics, elevated pretreatment CEA (HR 1.43; 95% CI 1.11-1.85, p < 0.001) and CA 19-9 (HR 1.79; 95% CI 1.42-2.25, p < 0.001) were associated with worse OS. Likelihoods to receive potentially curative surgery were 86%, 77% and 60% for patients without elevated tumor marker versus either elevated CEA or CA 19-9 versus both elevated, respectively (p < 0.001). Although both preoperative presence of ctDNA and tumor markers were prognostic for survival, no association was found between these two parameters. CONCLUSION: CEA and CA 19-9 were independent prognostic factors for survival in a large cohort of European patients with resectable gastric cancer. No relationship was found between tumor markers and ctDNA. These factors could potentially guide treatment choices and should be included in future trials to determine their definitive position. TRIAL REGISTRATION: ClinicalTrial.gov identifier: NCT00407186. EudraCT number: 2006-00413032.

Health-Related Quality of Life in Locally Advanced Gastric Cancer: A Systematic Review.

BACKGROUND: Current treatment strategies have been designed to improve survival in locally advanced gastric cancer patients. Besides its impact on survival, treatment also affects health-related quality of life (HRQOL), but an overview of reported studies is currently lacking. The aim of this systematic review was therefore to determine the short- and long-term impact of chemotherapy, surgery, and (chemo)radiotherapy on HRQOL in locally advanced, non-metastatic gastric cancer patients. METHODS: A systematic review was performed including studies published between January 2000 and February 2021. We extracted studies published in Medline, Embase, and Scopus databases that assessed HRQOL in patients with locally advanced, non-metastatic gastric cancer treated with curative intent. Studies using non-validated HRQOL questionnaires were excluded. Short-term and long-term HRQOL were defined as HRQOL scores within and beyond 6 months after treatment, respectively. RESULTS: Initially, we identified 8705 articles (4037 of which were duplicates, i.e., 46%) and ultimately included 10 articles. Most studies reported that short-term HRQOL worsened in the follow-up period from 6 weeks to 3 months after surgery. However, recovery of HRQOL to preoperative levels occurred after 6 months. After completion of chemoradiotherapy, the same pattern was seen with worse HRQOL after treatment and a recovery of HRQOL after 6-12 months. CONCLUSIONS: In patients with locally advanced, non-metastatic gastric cancer, HRQOL deteriorated during the first 3 months after surgery and chemoradiotherapy. However, the long-term data showed a recovery of HRQOL after 6-12 months. To implement HRQOL in clinical decision making in current clinical practice, more research is needed.

Risk Factors for Metachronous Isolated Peritoneal Metastasis after Preoperative Chemotherapy and Potentially Curative Gastric Cancer Resection: Results from the CRITICS Trial.

Gastric cancer (GC) patients at high risk of developing peritoneal metastasis (PM) as a single site of metastasis after curative treatment may be candidates for adjuvant prophylactic strategies. Here we investigated risk factors for metachronous isolated PM in patients who were treated in the CRITICS trial (NCT00407186). Univariable and multivariable analyses on both metachronous isolated PM and 'other events', i.e., (concurrent) distant metastasis, locoregional recurrence or death, were performed using a competing risk model and summarized by cumulative incidences. Isolated PM occurred in 64 of the 606 (11%) included patients. Diffuse or mixed histological subtype, ypT4 tumor stage and LNhigh (ypN3 lymph node stage or a lymph node ratio >20%) were independent risk factors for isolated PM in both univariable and multivariable analyses. Likewise, LNhigh was an independent risk factor for 'other events'. Patients with tumors who were positive for all three independent risk factors had the highest two-year cumulative incidence of 43% for isolated PM development. In conclusion, diffuse or mixed histological subtype, ypT4 and LNhigh were identified as independent risk factors for isolated PM in patients treated with preoperative chemotherapy followed by surgical resection. The combination of these factors may identify a subgroup that may benefit from PM-preventing treatment strategies.

The Dutch-Belgian Registry of Stereotactic Body Radiation Therapy for Liver Metastases: Clinical Outcomes of 515 Patients and 668 Metastases.

PURPOSE: Although various studies have reported that stereotactic body radiation therapy (SBRT) for liver metastases has high local control rates and relatively low toxicity, most series included a small number of patients. We aimed to validate these outcomes in a large multi-institution patient cohort treated in accordance with a common protocol. METHODS AND MATERIALS: A shared web-based registry of patients with liver metastases treated with SBRT was developed by 13 centers (12 in the Netherlands and 1 in Belgium). All the centers had previously agreed on the items to be collected, the fractionation schemes, and the organs-at-risk constraints to be applied. Follow-up was performed at the discretion of the centers. Patient, tumor, and treatment characteristics were entered in the registry. Only liver metastases treated individually as independent targets and with at least 1 radiologic follow-up examination were considered for local control analysis. Toxicity of grade 3 or greater was scored according to the Common Terminology Criteria of Adverse Events (v4.03). RESULTS: Between January 1, 2013, and July 31, 2019, a total of 515 patients were entered in the web-based registry. The median age was 71 years. In total, 668 liver metastases were registered, and 447 were included for local control analysis. The most common primary tumor origin was colorectal cancer (80.3%), followed by lung cancer (8.9%) and breast cancer (4%). The most-used fractionation scheme was 3x18-20 Gy (36.0%), followed by 8x7.5 Gy (31.8%), 5x11-12 Gy (25.5%), and 12x5 Gy (6.7%). The median follow-up time was 1.1 years for local control and 2.3 years for survival. Actuarial 1-year local control was 87%; 1-year overall survival was 84%. Toxicity of grade 3 or greater was found in 3.9% of the patients. CONCLUSIONS: This multi-institutional study confirms the high rates of local control and limited toxicity in a large patient cohort. Stereotactic body radiation therapy should be considered a valuable part of the multidisciplinary approach to treating liver metastases.

Towards Personalization in the Curative Treatment of Gastric Cancer.

Gastric cancer is the fifth most common cancer worldwide and has a high mortality rate. In the last decades, treatment strategy has shifted from an exclusive surgical approach to a multidisciplinary strategy. Treatment options for patients with resectable gastric cancer as recommended by different worldwide guidelines, include perioperative chemotherapy, pre- or postoperative chemoradiotherapy and postoperative chemotherapy. Although gastric cancer is a heterogeneous disease with respect to patient-, tumor-, and molecular characteristics, the current standard of care is still according to a one-size-fits-all approach. In this review, we discuss the background of the different treatment strategies in resectable gastric cancer including the current standard, the specific role of radiotherapy, and describe the current areas of research and potential strategies for personalization of therapy.

Venous thromboembolism during preoperative chemotherapy in the CRITICS gastric cancer trial.

BACKGROUND: The occurrence of a venous thromboembolism (VTE) is common in patients with cancer. Gastric cancer has been associated with one of the highest risks for VTE. Chemotherapy, especially cisplatin has been associated with a high VTE risk. In this study, risk factors for VTE occurrence and their potential impact on subsequent therapeutic interventions were investigated in patients who underwent preoperative chemotherapy, in the CRITICS gastric cancer trial. PATIENTS AND METHODS: Patients with resectable gastric cancer were preoperatively treated with three cycles of 3-weekly epirubicin, cisplatin or oxaliplatin, and capecitabine (ECC/EOC). VTE was defined as any thrombus in the venous system, excluding superficial and/or device related VTEs. Potential risk factors were analyzed in a multivariable regression model with age, gender, Body Mass Index (BMI), tumor localization, Lauren classification, type of chemotherapy (ECC/EOC), (cardiovascular) comorbidity, and previous VTE as independent risk factors. The impact of VTE on completion rate of preoperative chemotherapy, surgical resection rate, postoperative complications, and start of postoperative therapy were investigated. RESULTS: Of 781 patients, 78 (10%) of 781 patients developed a VTE during preoperative chemotherapy. On multivariable analysis, BMI ≥ 30 kg/m2 and previous VTE were associated with VTE occurrence (reference BMI < 25 kg/m2 ; OR 2.190; 95% CI 1.152-4.164; P = .017/previous VTE; OR 3.617; 95% CI 1.201-10.890; P = .022). Treatment with cisplatin was, compared to oxaliplatin, not significantly associated with VTE occurrence (OR 1.535; 95% CI 0.761-3.094; P = .231). VTE occurrence did not affect completion of preoperative chemotherapy, surgical resection rate, postoperative complications, or start of postoperative therapy. CONCLUSION: High BMI and previous VTE were independent risk factors for VTE occurrence during preoperative chemotherapy in patients with resectable gastric cancer. VTE occurrence in the preoperative setting did not affect receipt of further treatment.

Older versus younger adults with gastric cancer receiving perioperative treatment: Results from the CRITICS trial.

AIM: To evaluate treatment-related toxicity, treatment compliance, surgical complications and event-free survival (EFS) in older (≥70 years) versus younger (<70 years) adults who underwent perioperative treatment for gastric cancer. METHODS: In the CRITICS trial, 788 patients with resectable gastric cancer were randomised before start of any treatment and received preoperative chemotherapy (3 cycles of epirubicin, cisplatin or oxaliplatin and capecitabine), followed by surgery, followed by either postoperative chemotherapy or chemoradiotherapy (45Gy + cisplatin + capecitabine). RESULTS: 172 (22%) patients were older adults. During preoperative chemotherapy, 131 (77%) older adults versus 380 (62%) younger adults experienced severe toxicity (p < 0.001); older adults received significantly lower relative dose intensities (RDIs) for all chemotherapeutic drugs. Equal proportions of older versus younger adults underwent curative surgery: 137 (80%) versus 499 (81%), with comparable postoperative complications and postoperative mortality. Postoperative therapy after curative surgery started in 87 (64%) older adults versus 391 (78%) younger adults (p < 0.001). Incidence of severe toxicity during postoperative chemotherapy was 22 (54%) in older adults versus 113 (59%) in younger adults (p = 0.541); older adults received significantly lower RDIs for all chemotherapeutic drugs. Severe toxicity rates for postoperative chemoradiotherapy were 22 (48%) older adults versus 89 (45%) for younger adults (p = 0.703), with comparable chemotherapy RDIs and radiotherapy dose. Two-year EFS was 53% for older adults versus 51% for younger adults. CONCLUSION: Perioperative treatment compliance, especially in the postoperative phase, was poorer in older adults compared with younger adults. As comparable proportions of patients underwent curative surgery, future studies should focus on neo-adjuvant treatment. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00407186. EudraCT number: 2006-00413032.

White blood cell and cell-free DNA analyses for detection of residual disease in gastric cancer.

Liquid biopsies are providing new opportunities for detection of residual disease in cell-free DNA (cfDNA) after surgery but may be confounded through identification of alterations arising from clonal hematopoiesis. Here, we identify circulating tumor-derived DNA (ctDNA) alterations through ultrasensitive targeted sequencing analyses of matched cfDNA and white blood cells from the same patient. We apply this approach to analyze samples from patients in the CRITICS trial, a phase III randomized controlled study of perioperative treatment in patients with operable gastric cancer. After filtering alterations from matched white blood cells, the presence of ctDNA predicts recurrence when analyzed within nine weeks after preoperative treatment and after surgery in patients eligible for multimodal treatment. These analyses provide a facile method for distinguishing ctDNA from other cfDNA alterations and highlight the utility of ctDNA as a predictive biomarker of patient outcome to perioperative cancer therapy and surgical resection in patients with gastric cancer.

High versus low dose Stereotactic Body Radiation Therapy for hepatic metastases.

INTRODUCTION: Stereotactic Body Radiation Therapy (SBRT) is a treatment option for patients with liver metastases. This study evaluated the impact of high versus low dose image-guided SBRT of hepatic metastases. METHODS AND MATERIALS: This is a single-center retrospective study of patients with liver metastases treated with SBRT. For analyses, patients were divided into two groups: ≤100 Gy and >100 Gy near-minimum Biological Effective Doses (BED98%). The main outcomes were local control (LC), toxicity and overall survival (OS). Cox regression analyses were performed to determine prognostic variables on LC and OS. RESULTS: Ninety patients with 97 liver metastases (77% colorectal) were included. Median follow-up was 28.6 months. The two-year LC rates in the ≤100 Gy and >100 Gy BED98% group were 60% (CI: 41-80%) and 90% (CI: 80-100%), respectively (p = 0.004). Grade 3 toxicity occurred in 7% vs 2% in the ≤100 Gy and >100 Gy group (p = 0.23). Two-year OS rates in the ≤100 Gy and >100 Gy group were 48% (CI: 32-65%) and 85% (CI: 73-97%), respectively (p = 0.007). In multivariable Cox regression analyses, group dose and tumor volume were significantly correlated with LC (HR: 3.61; p = 0.017 and HR: 1.01; p = 0.005) and OS (HR: 2.38; p = 0.005 and HR: 1.01; p = <0.0001). CONCLUSION: High dose SBRT provides significantly better local control and overall survival than low dose SBRT without increasing toxicity. When surgical resection is not feasible, high dose SBRT provides an effective and safe treatment for liver metastases.

Gross Tumor Delineation in Esophageal Cancer on MRI Compared With 18F-FDG-PET/CT.

PURPOSE: Current delineation of the gross tumor volume (GTV) in esophageal cancer relies on computed tomography (CT) and combination with 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET). There is increasing interest in integrating magnetic resonance imaging (MRI) in radiation treatment, which can potentially obviate CT- or FDG-PET/CT-based delineation. The aim of this study is to evaluate the feasibility of target delineation on T2-weighted (T2W) MRI and T2W including diffusion-weighted MRI (T2W + DW-MRI) compared with current-practice FDG-PET/CT. METHODS: Ten observers delineated primary esophageal tumor GTVs of 6 patients on FDG-PET/CT, T2W-MRI, and T2W + DW-MRI. GTVs, generalized conformity indices, in-slice delineation variation (root mean square), and standard deviations in the position of the most cranial and caudal delineated slice were calculated. RESULTS: Delineations on MRI showed smaller GTVs compared with FDG-PET/CT-based delineations. The main variation was seen at the cranial and caudal border. No differences were observed in conformity indices (FDG-PET/CT, 0.68; T2W-MRI, 0.66; T2W + DW-MRI, 0.68) and in-slice variation (root mean square, 0.13 cm on FDG-PET/CT; 0.10 cm on T2W-MRI; 0.14 cm on T2W + DW-MRI). In the 2 tumors involving the gastroesophageal junction, addition of DW-MRI to T2W-MRI significantly decreased caudal border variation. CONCLUSIONS: MRI-based target delineation of the esophageal tumor is feasible with interobserver variability comparable to that with FDG-PET/CT, despite limited experience with delineation on MRI. Most variation was seen at cranial-caudal borders, and addition of DW-MRI to T2W-MRI may reduce caudal delineation variation of gastroesophageal junction tumors.

Investigating the impact of patient arm position in an MR-linac on liver SBRT treatment plans.

PURPOSE: The superior soft-tissue contrast offered by the integrated magnetic resonance imaging (MRI) of the Unity MR-linac compared to the x-ray-based image guidance on conventional linacs potentially allows for liver stereotactic body radiation therapy (SBRT) without the need for implanted markers or other surrogates. On conventional linacs, liver SBRT patients are typically positioned with their arms above their heads (arms-up) to minimize exposure to healthy tissue. However, the spatial confinement of the MRI-bore and increased treatment delivery times can make the arms-up position straining. Therefore, we assessed the plan quality for MR-linac treatment plans with the patient in the arms-up and in the arms-down position. Additionally, we compared the MR-linac plans with clinically used arms-up treatment plans made for a conventional linac. METHODS: Fifteen consecutively treated patients with oligometastatic liver disease were included in this retrospective study. For each patient, a planning computed tomography (CT) with delineations, a diagnostic MRI, and a 3 × 20 Gy dual-arc volumetric modulated arc therapy (VMAT) plan, which was used to treat the patient in an arms-up position on the conventional linac, were available. For the MR-linac, 15-beam step-and-shoot intensity-modulated radiation therapy (IMRT) plans were created for four patient positioning scenarios: arms-up, mimicking current clinical practice; arms-down, with treatment beams avoiding the arms on the entrance side; arms-through, arms are down but not avoided, and right-arm-up; only the right arm is up and the left arm is avoided on the entrance side. Resulting treatment plans were compared. Bonferroni-corrected two-sided Wilcoxon signed-ranks tests were used to assess statistical significance (P < 0.05). RESULTS: No significant differences were found in gross tumour volume (GTV) coverage (D 2 % , D 50 % , and D 98 % ) or liver sparing (liver-GTV V < 15 Gy ) between the clinical plans and any of the MR-linac plans. The median target conformity [exterior V 40 % /planning target volume (PTV)] was significantly better in the clinical plans (5.8) than in the MR-linac scenarios (arms-down: 6.6, arms-up/right-arm-up: 6.2, arms-through: 6.3). No MR-linac plan violated any additional organ-at-risk (OAR) constraint that was not already violated in the clinical plans. In the arms-down scenario a significantly increased median spinal cord D 1 % (14.5 Gy) was detected compared to the clinical setup (7.2 Gy). For the arms-down (arms-through) scenario, the median left arm D 1 % was 1.5 (2.7) Gy, the median right arm D 1 % was 5.8 (22.7) Gy, and the median right arm V 20 Gy was 0.0 (14.7) cc. These differences were statistically significant. For the right-arm-up scenario, the median left arm D 1 % (2.3 Gy) and V 5 Gy (0.0) were not significantly different compared to the arms-down scenario. CONCLUSIONS: Mimicking the current clinical practice by treating patients in the arms-up/right-arm-up position on the MR-linac leads to plans which are dosimetrically very similar to the conventional linac plans. Treating in the arms-down position is expected to increase patient comfort at the cost of a small reduction in OAR sparing for individual patients. Treating through the arms is not encouraged due to substantial dose deposition in the arms.

Imaging strategies in the management of gastric cancer: current role and future potential of MRI.

Accurate preoperative staging of gastric cancer and the assessment of tumor response to neoadjuvant treatment is of importance for treatment and prognosis. Current imaging techniques, mainly endoscopic ultrasonography (EUS), computed tomography (CT) and 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET), have their limitations. Historically, the role of magnetic resonance imaging (MRI) in gastric cancer has been limited, but with the continuous technical improvements, MRI has become a more potent imaging technique for gastrointestinal malignancies. The accuracy of MRI for T- and N-staging of gastric cancer is similar to EUS and CT, making MRI a suitable alternative to other imaging strategies. There is limited evidence on the performance of MRI for M-staging of gastric cancer specifically, but MRI is widely used for diagnosing liver metastases and shows potential for diagnosing peritoneal seeding. Recent pilot studies showed that treatment response assessment as well as detection of lymph node metastases and systemic disease might benefit from functional MRI (e.g. diffusion weighted imaging and dynamic contrast enhancement). Regarding treatment guidance, additional value of MRI might be expected from its role in better defining clinical target volumes and setup verification with MR-guided radiation treatment.

Effect of Hospital Volume With Respect to Performing Gastric Cancer Resection on Recurrence and Survival: Results From the CRITICS Trial.

OBJECTIVE: We examined the association between surgical hospital volume and both overall survival (OS) and disease-free survival (DFS) using data obtained from the international CRITICS (ChemoRadiotherapy after Induction chemotherapy In Cancer of the Stomach) trial. SUMMARY BACKGROUND DATA: In the CRITICS trial, patients with resectable gastric cancer were randomized to receive preoperative chemotherapy followed by adequate gastrectomy and either chemotherapy or chemoradiotherapy. METHODS: Patients in the CRITICS trial who underwent a gastrectomy with curative intent in a Dutch hospital were included in the analysis. The annual number of gastric cancer surgeries performed at the participating hospitals was obtained from the Netherlands Cancer Registry; the hospitals were then classified as low-volume (1-20 surgeries/year) or high-volume (≥21 surgeries/year) and matched with the CRITICS trial data. Univariate and multivariate analyses were then performed to evaluate the hazard ratio (HR) between hospital volume and both OS and DFS. RESULTS: From 2007 through 2015, 788 patients were included in the CRITICS trial. Among these 788 patients, 494 were eligible for our study; the median follow-up was 5.0 years. Five-year OS was 59.2% and 46.1% in the high-volume and low-volume hospitals, respectively. Multivariate analysis revealed that undergoing surgery in a high-volume hospital was associated with higher OS [HR = 0.69, 95% confidence interval (CI) = 0.50-0.94, P = 0.020] and DFS (HR = 0.73, 95% CI: 0.54-0.99, P = 0.040). CONCLUSIONS: In the CRITICS trial, hospitals with a high annual volume of gastric cancer surgery were associated with higher overall and DFS. These findings emphasize the value of centralizing gastric cancer surgeries in the Western world.

CRITICS-II: a multicentre randomised phase II trial of neo-adjuvant chemotherapy followed by surgery versus neo-adjuvant chemotherapy and subsequent chemoradiotherapy followed by surgery versus neo-adjuvant chemoradiotherapy followed by surgery in resectable gastric cancer.

BACKGROUND: Although radical surgery remains the cornerstone of cure in resectable gastric cancer, survival remains poor. Current evidence-based (neo)adjuvant strategies have shown to improve outcome, including perioperative chemotherapy, postoperative chemoradiotherapy and postoperative chemotherapy. However, these regimens suffer from poor patient compliance, particularly in the postoperative phase of treatment. The CRITICS-II trial aims to optimize preoperative treatment by comparing three treatment regimens: (1) chemotherapy, (2) chemotherapy followed by chemoradiotherapy and (3) chemoradiotherapy. METHODS: In this multicentre phase II non-comparative study, patients with clinical stage IB-IIIC (TNM 8th edition) resectable gastric adenocarcinoma are randomised between: (1) 4 cycles of docetaxel+oxaliplatin+capecitabine (DOC), (2) 2 cycles of DOC followed by chemoradiotherapy (45Gy in combination with weekly paclitaxel and carboplatin) or (3) chemoradiotherapy. Primary endpoint is event-free survival, 1 year after randomisation (events are local and/or regional recurrence or progression, distant recurrence, or death from any cause). Secondary endpoints include: toxicity, surgical outcomes, percentage radical (R0) resections, pathological tumour response, disease recurrence, overall survival, and health related quality of life. Exploratory endpoints include translational studies on predictive and prognostic biomarkers. DISCUSSION: The aim of this study is to select the most promising among three preoperative treatment arms in patients with resectable gastric adenocarcinoma. This treatment regimen will subsequently be compared with the standard therapy in a phase III trial. TRIAL REGISTRATION: clinicaltrials.gov NCT02931890 ; registered 13 October 2016. Date of first enrolment: 21 December 2017.

Chemotherapy versus chemoradiotherapy after surgery and preoperative chemotherapy for resectable gastric cancer (CRITICS): an international, open-label, randomised phase 3 trial.

BACKGROUND: Both perioperative chemotherapy and postoperative chemoradiotherapy improve survival in patients with resectable gastric cancer from Europe and North America. To our knowledge, these treatment strategies have not been investigated in a head to head comparison. We aimed to compare perioperative chemotherapy with preoperative chemotherapy and postoperative chemoradiotherapy in patients with resectable gastric adenocarcinoma. METHODS: In this investigator-initiated, open-label, randomised phase 3 trial, we enrolled patients aged 18 years or older who had stage IB- IVA resectable gastric or gastro-oesophageal adenocarcinoma (as defined by the American Joint Committee on Cancer, sixth edition), with a WHO performance status of 0 or 1, and adequate cardiac, bone marrow, liver, and kidney function. Patients were enrolled from 56 hospitals in the Netherlands, Sweden, and Denmark, and were randomly assigned (1:1) with a computerised minimisation programme with a random element to either perioperative chemotherapy (chemotherapy group) or preoperative chemotherapy with postoperative chemoradiotherapy (chemoradiotherapy group). Randomisation was done before patients were given any preoperative chemotherapy treatment and was stratified by histological subtype, tumour localisation, and hospital. Patients and investigators were not masked to treatment allocation. Surgery consisted of a radical resection of the primary tumour and at least a D1+ lymph node dissection. Postoperative treatment started within 4-12 weeks after surgery. Chemotherapy consisted of three preoperative 21-day cycles and three postoperative cycles of intravenous epirubicin (50 mg/m2 on day 1), cisplatin (60 mg/m2 on day 1) or oxaliplatin (130 mg/m2 on day 1), and capecitabine (1000 mg/m2 orally as tablets twice daily for 14 days in combination with epirubicin and cisplatin, or 625 mg/m2 orally as tablets twice daily for 21 days in combination with epirubicin and oxaliplatin), received once every three weeks. Chemoradiotherapy consisted of 45 Gy in 25 fractions of 1·8 Gy, for 5 weeks, five daily fractions per week, combined with capecitabine (575 mg/m2 orally twice daily on radiotherapy days) and cisplatin (20 mg/m2 intravenously on day 1 of each 5 weeks of radiation treatment). The primary endpoint was overall survival, analysed by intention-to-treat. The CRITICS trial is registered at ClinicalTrials.gov, number NCT00407186; EudraCT, number 2006-004130-32; and CKTO, 2006-02. FINDINGS: Between Jan 11, 2007, and April 17, 2015, 788 patients were enrolled and randomly assigned to chemotherapy (n=393) or chemoradiotherapy (n=395). After preoperative chemotherapy, 372 (95%) of 393 patients in the chemotherapy group and 369 (93%) of 395 patients in the chemoradiotherapy group proceeded to surgery, with a potentially curative resection done in 310 (79%) of 393 patients in the chemotherapy group and 326 (83%) of 395 in the chemoradiotherapy group. Postoperatively, 233 (59%) of 393 patients started chemotherapy and 245 (62%) of 395 started chemoradiotherapy. At a median follow-up of 61·4 months (IQR 43·3-82·8), median overall survival was 43 months (95% CI 31-57) in the chemotherapy group and 37 months (30-48) in the chemoradiotherapy group (hazard ratio from stratified analysis 1·01 (95% CI 0·84-1·22; p=0·90). After preoperative chemotherapy, in the total safety population of 781 patients (assessed together), there were 368 (47%) grade 3 adverse events; 130 (17%) grade 4 adverse events, and 13 (2%) deaths. Causes of death during preoperative treatment were diarrhoea (n=2), dihydropyrimidine deficiency (n=1), sudden death (n=1), cardiovascular events (n=8), and functional bowel obstruction (n=1). During postoperative treatment, grade 3 and 4 adverse events occurred in 113 (48%) and 22 (9%) of 233 patients in the chemotherapy group, respectively, and in 101 (41%) and ten (4%) of 245 patients in the chemoradiotherapy group, respectively. Non-febrile neutropenia occurred more frequently during postoperative chemotherapy (79 [34%] of 233) than during postoperative chemoradiotherapy (11 [4%] of 245). No deaths were observed during postoperative treatment. INTERPRETATION: Postoperative chemoradiotherapy did not improve overall survival compared with postoperative chemotherapy in patients with resectable gastric cancer treated with adequate preoperative chemotherapy and surgery. In view of the poor postoperative patient compliance in both treatment groups, future studies should focus on optimising preoperative treatment strategies. FUNDING: Dutch Cancer Society, Dutch Colorectal Cancer Group, and Hoffmann-La Roche.

Surgicopathological Quality Control and Protocol Adherence to Lymphadenectomy in the CRITICS Gastric Cancer Trial.

OBJECTIVE: The purpose of this study was to evaluate surgicopathological quality and protocol adherence for lymphadenectomy in the CRITICS trial. SUMMARY OF BACKGROUND DATA: Surgical quality assurance is a key element in multimodal studies for gastric cancer. In the multicenter CRITICS trial (ChemoRadiotherapy after Induction chemotherapy In Cancer of the Stomach), patients with resectable gastric cancer were randomized for preoperative chemotherapy, followed by gastrectomy with a D1+ lymphadenectomy (removal of stations 1 to 9 and 11), followed by either chemotherapy or chemoradiotherapy. METHODS: Surgicopathological compliance was defined as removal of ≥15 lymph nodes. Surgical compliance was defined as removal of the indicated lymph node stations. Surgical contamination was defined as removal of lymph node stations that should be left in situ. The Maruyama Index (MI, lower is better), which has proven to be an indicator of surgical quality and is strongly associated with survival, was analyzed. RESULTS: Between 2007 and 2015, 788 patients were randomized, of whom 636 patients underwent a gastrectomy with curative intent. Surgicopathological compliance occurred in 72.8% (n = 460) of the patients and improved from 55.0% (2007) to 90.0% (2015). Surgical compliance occurred in 41.1% (n = 256). Surgical contamination occurred in 59.6% (n = 371). Median MI was 1 (range 0 to 136). CONCLUSION: Surgical quality in the CRITICS trial was excellent, with a MI of 1. Surgicopathological compliance improved over the years. This might be explained by the quality assurance program within the study and centralization of gastric cancer surgery in the Netherlands.