The advent of immune checkpoint inhibitors has driven progress in hepatocellular carcinoma (HCC) treatment outcomes and enabled opportunities for combining therapeutic modalities. Growing evidence substantiates the utility of radiotherapy, particularly at ablative doses, in the management of HCC. Given the potential for radiotherapy to induce an immunostimulatory environment and potentiate immune checkpoint inhibitor activity, the expanding HCC treatment landscape compels exploration of the combination of radiotherapy and immunotherapy. This review highlights recent advances in the treatment of HCC using radiotherapy and immunotherapy in combination. Radiation can potentiate an anti-tumor response and tumor microenvironment permissive to immunotherapy. Results from randomized clinical trials and retrospective studies consistently show that combinations of radiotherapy and immunotherapy improved the treatment outcomes of unresectable or advanced HCC—especially HCC with macrovascular invasion. Active research to further improve treatment efficacy and reduce side effects is exemplified by more than 20 ongoing clinical trials combining external beam radiotherapy and immunotherapy to treat HCC. Ongoing research aims at prolonging survival and downstaging advanced or unresectable HCC.

PURPOSE:This trial examined if patients with ≤5 sites of oligoprogression benefit from the addition of SABR to standard of care (SOC) systemic therapy. METHODS AND MATERIALS:We enrolled patients with 1 to 5 metastases progressing on systemic therapy, and after stratifying by type of systemic therapy (cytotoxic vs noncytotoxic), randomized 1:2 between continued SOC treatment versus SABR to all progressing lesions plus SOC. The trial was initially limited to non-small cell lung cancer but was expanded to include all nonhematologic malignancies to meet accrual goals. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), lesional control, quality of life, adverse events, and duration of systemic therapy postrandomization. RESULTS:Ninety patients with 127 oligoprogressive metastases were enrolled across 8 Canadian institutions, with 59 randomized to SABR and 31 to SOC. The median age was 67 years, and 39 (43%) were women. The most common primary sites were lung (44%), genitourinary (23%), and breast (13%). Protocol adherence in the SOC arm was suboptimal, with 11 patients (35%) either receiving high-dose/ablative therapies (conflicting with trial protocol) or withdrawing from the study. The median follow-up was 31 months. There was no difference in PFS between arms (median PFS 8.4 months in the SABR arm vs 4.3 months in the SOC arm, but curves cross and 2-year PFS was 9% vs 24%, respectively; P = .91). The median OS was 31.2 months versus 27.4 months, respectively (P = .22). Lesional control was superior with SABR (70% vs 38%, respectively; P = .0015). There were 2 (3.4%) grade 3 and no grade 4/5 adverse events attributable to SABR. CONCLUSIONS:SABR was well-tolerated with superior lesional control but did not improve PFS or OS. Accrual to this study was difficult, and the results may have been impacted by an unwillingness to forgo ablative treatments on the SOC arm. (NCT02756793).

Background: Stereotactic body radiotherapy (SBRT) is an evolving treatment for the local management of pancreatic cancer (PC). The main purpose of this study is to report our initial experience in terms of local control (LC) and toxicity for PC patients treated with SBRT. Methods: We conducted a retrospective review of patients treated with SBRT using abdominal compression (AC) or an end-expiratory breath-holding (EEBH) technique. The median prescribed dose was 35 Gy, delivered in five fractions. Toxicities were recorded using Common Terminology Criteria for Adverse Events (CTCAE) v5.0, and survival was estimated using the Kaplan–Meier method. Results: From 2017 to 2023, 17 PC patients were offered SBRT. Their median age was 69 years. The median follow-up from the date of diagnosis was 22.37 months. The overall survival (OS) was 94% at 1 year and 60.9% at 2 years. The progression-free survival (PFS) was 63.1% at 6 months and 56.1% at 9 months. The median OS was 26.3 months, and the median PFS was 20.6 months. The 6-month and 1-year LC rates were 71% and 50.8%, respectively. Conclusion: We are successful in implementing the SBRT program at our centre. SBRT appears to be a promising treatment option for achieving LC with limited acute toxicities.

Purpose For a high-volume brachytherapy (BT) service, traditionally treating locally advanced cervical cancers (LACC) with single insertion MRI-planned pulsed-dose-rate (PDR) BT boost, a complete transition to multi-insertion high-dose-rate (HDR) treatment delivery, had significant intra- and extra-departmental implications on resource management, people, and processes. We summarize our multi-team approach and organizational initiatives, including a Process Design Committee (PDC), to facilitate seamless transition and ensure ongoing BT care to a high standard. Materials and Methods Despite a steadily growing volume of LACC patients (2007 - 2023; 40-50 cases/year), our longstanding carepath was single insertion, 58-pulse (hours) PDR BT, requiring 3 nights’ admission, while meeting an overall treatment time (OTT) of 50 days from start of external beam treatment (EBRT) (Fig A(a)). The change to HDR required doubling of operating room (OR)-based applicator insertions (2 fractions/insertion), additional US/CT/MR imaging for guidance/verification/planning, while working with the same 1 day/week OR availability. To plan for the increased load (Fig B), a PDC was assembled, with representation from all stakeholders to design a sustainable and robust HDR program. A novel workflow simulation tool was created, iteratively incorporating solutions to concerns and barriers, optimizing clinical translation. Results The PDC was formed 16 months in advance of the planned full transition to HDR. An experienced process improvement specialist led weekly multidisciplinary (radiation therapists, physicians, physicists, OR nurses, managers, etc.) meetings to map and review existing processes, identify current and future challenges likely to have major impact during transition such as utilizing available OR time, OTT, staffing, equipment (including applicator inventory), patient scheduling, and wait times. A pipeline communication tool (PCT) was developed using an agent-based model with discreet event simulation to test future state journeys on how to manage the doubled workload, tight timelines, staffing, and limited OR availability. The PDC and key personnel completed brainstorming sessions to identify smoothing solutions for a large repository of simulated scenarios. Recommendations to modify existing practice to accommodate change and improve efficiency included treating 3 patients/OR day, performing first BT insertion before the end of EBRT, procuring more applicators and additional planning software licenses, staggering staff shifts, and promoting structured transfer-of-care procedures. These smoothing solutions were tested using the PCT in select representative sample scenarios. We could improve OR utilization from approximately 40% to nearly 100%, in addition to managing the increased demand for procedures, maintaining patient wait times, and reducing staff overtime costs. To test the feasibility of the PCT for clinical implementation in a safe manner, HDR treatments were incrementally integrated into our PDR LACC BT program from early 2023 (Fig A(b)). A continuous process improvement loop was incorporated into the PCT, with systematic collection and analysis of feedback, which assisted the team in a seamless transition to a comprehensive HDR BT program for LACC in 10/2023. Conclusion Prospective assessment of diverse factors impacting a significant practice change, with task-specific focus and implementation of interventions, ensured smooth transition to HDR delivery LACC BT. Engaging a quality improvement consultant for process redesign enhanced efficiency.

PurposeWe report the impact of 1 vs. 2 doses of mitomycin-C (MMC) based chemoradiation (CRT) on patterns of treatment failure and long-term patient outcomes in anal squamous cell carcinoma (ASCC) and the predictors for locoregional failure (LRF) and distant metastasis (DM).MethodsIn this population-based study, we identified all patients with anal cancer in our province treated radically with radiation and concurrent 5-Fluorouracil (5FU) and 1 vs. 2 doses of MMC between the years 2000-2019. The primary outcomes analyzed were locoregional recurrence (LRR), disease free survival (DFS), ASCC cancer-specific survival (ASCC-CSS) and overall survival (OS).Results451 patients were identified. 272 (60%) patients received 1 cycle of MMC (MMC1) and 179 (40%) received 2 cycles (MMC2) as part of the CRT regimen. The median follow-up was 57 (36-252) and 97 (38-239) months for MMC1 and MMC2, respectively. Cox Regression analysis showed stage IIIb and IIIc were associated with worse locoregional recurrence free survival (RFS) (HR=2.851, p=<0.001) and distant RFS (HR=3.391, p=<0.001). Similarly, stage IIIb and IIIc patients had poorer DFS (HR 3.439, p=<0.001), ASCC-SS (HR 3.729, p=<0.001) and OS (2.230, p=<0.001). The use of MMC2 showed a positive impact on improved ASCC-SS (HR 0.569, p=0.029) and distant RFS (HR 0.555, p=0.040) in patients with stage IIIb and IIIc.ConclusionsOur analysis showed that 1 vs. 2 cycles of MMC along with 5FU and radiation is associated with comparable treatment outcomes in general. However, in patients with stage IIIb and IIIc cancer, 2 doses of MMC were associated with improved ASCC-SS and distant DFS.

PURPOSE:Intensity modulated radiation therapy (IMRT) has confirmed its superiority in improving acute treatment-related toxicities in anal cancer, without compromising tumor control. However, the effect of IMRT on long-term quality of life (QOL) is poorly documented. The study prospectively evaluated the long-term patient-reported QOL after IMRT-based chemoradiation in anal cancer.METHODS AND MATERIALS:Fifty-eight patients treated with IMRT and concurrent 5 fluorouracil/mitomycin-C were enrolled in the study. A prespecified secondary endpoint was prospective evaluation of long-term QOL. Fifty-four patients underwent QOL evaluation at baseline, after treatment, and during follow-up until 60 months, with European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (EORTC QLQ-C30) scales and the Colorectal Cancer-Specific Quality Of Life Questionnaire (QLQ-CR29) scales. The QOL scores at baseline and posttreatment periods were compared.RESULTS:For QLQ-C30, at 60 months, the mean scores of global health status, all functional scales, and all symptoms except diarrhea had improved, indicating normalization of QOL. Clinically and statistically significant improvements in the global health status (15.4; P = .003), role functioning (19.3; P = .0017), emotional functioning (18.9; P = .008), and social functioning (29.8; P ≤ .001) were observed. Diarrhea persisted as a concern over the years (P = .172). For European Organization for Research and Treatment of Cancer QLQ-CR29, rectal pain (-38.6; P = .001), mucous or blood discharge per rectum (-22.8; P = .005), and perianal soreness (-37.3; P ≤ .001) were improved both clinically and statistically. Clinically significant fecal leakage was reported by 16% of patients (5.6; P = .421). Volumes receiving 45 and 54 Gy were independent predictors for fecal incontinence. Clinically and statistically significant urinary incontinence occurred in 21% of patients (17.5; P = .014). Deterioration of dyspareunia was clinically significant (26.7; P = .099) at 60 months.CONCLUSIONS:Compared with historical data, IMRT is associated with reduced long-term effects on QOL. The majority of patients treated with IMRT experienced clinically significant recovery of function and improvement in QOL over 5 years after completion of treatment. Specific toxicities such as chronic diarrhea, fecal incontinence, and urinary and sexual dysfunction were primarily responsible for deterioration of the long-term QOL. Future research aimed at reducing such toxicities is needed to further improve long-term QOL in anal cancer.

MR-based radiomics predict LC post-SBRT in patients with malignant liver tumors. Further research focused on independent validation of the model is required to explore its clinical use.

Objectives: Understanding exercise motivation in rectal cancer patients during and after neoadjuvant chemo-radiation therapy is important to improve adherence and achieve potential benefit. We report the motivational effects of exercise from the Exercise During and After Neoadjuvant Rectal Cancer Treatment trial.Data Sources: We randomized 36 rectal cancer patients to supervised high-intensity interval training during neoadjuvant chemoradiation therapy followed by unsupervised moderate-to-vigorous exercise after therapy, or usual care. Using the theory of planned behavior, we assessed motivation, perceived benefits/harms, and perceived barriers for exercise during and after therapy. Supervised exercise during neoadjuvant chemo-radiation therapy was experienced as meaningfully (d=0.33) more controllable (p=0.08, d=0.60), more enjoy-able (p=0.25, d=0.45), and less difficult (p=0.45, d=-0.38) than anticipated. Unsupervised exercise after therapy was experienced as meaningfully more enjoyable (p=0.047, d=0.50) and less difficult (p=0.43, d=-0.36), but also less controllable (p=0.14, d=-0.80) than anticipated. Common self-reported benefits of exercise both during and after neoadjuvant chemoradiation therapy were cardiovascular endurance, physical functioning, and quality of life. Common self-reported harms were exacerbation of treatment side effects. Frequently reported barriers to exercise during therapy were side effects of treatment, whereas exercise barriers after therapy were lack of motivation and lingering side effects.Conclusion: Exercise during and after therapy generally had positive effects on exercise motivation, however, perceived harms and barriers related to treatment side effects were identified.

Importance:Pathologic complete response (pCR) may be associated with prognosis in patients with soft tissue sarcoma (STS).Objective:We sought to determine the prognostic significance of pCR on survival outcomes in STS for patients receiving neoadjuvant chemoradiotherapy (CT-RT) (Radiation Therapy Oncology Group [RTOG] 9514) or preoperative image-guided radiotherapy alone (RT, RTOG 0630) and provide a long-term update of RTOG 0630.Design, Setting, and Participants:RTOG has completed 2 multi-institutional, nonrandomized phase 2 clinical trials for patients with localized STS. One hundred forty-three eligible patients from RTOG 0630 (n = 79) and RTOG 9514 (n = 64) were included in this ancillary analysis of pCR and 79 patients from RTOG 0630 were evaluated for long-term outcomes.Intervention:Patients in trial 9514 received CT interdigitated with RT, whereas those in trial 0630 received preoperative RT alone.Main Outcomes and Measures:Overall and disease-free survival (OS and DFS) rates were estimated by the Kaplan-Meier method. Hazard ratios (HRs) and P values were estimated by multivariable Cox model stratified by study, where possible; otherwise, P values were calculated by stratified log-rank test. Analysis took place between December 14, 2016, to April 13, 2017.Results:Overall there were 42 (53.2%) men; 68 (86.1%) were white; with a mean (SD) age of 59.6 (14.5) years. For RTOG 0630, at median follow-up of 6.0 years, there was 1 new in-field recurrence and 1 new distant failure since the initial report. From both studies, 123 patients were evaluable for pCR: 14 of 51 (27.5%) in trial 9514 and 14 of 72 (19.4%) in trial 0630 had pCR. Five-year OS was 100% for patients with pCR vs 76.5% (95% CI, 62.3%-90.8%) and 56.4% (95% CI, 43.3%-69.5%) for patients with less than pCR in trials 9514 and 0630, respectively. Overall, pCR was associated with improved OS (P = .01) and DFS (HR, 4.91; 95% CI, 1.51-15.93; P = .008) relative to less than pCR. Five-year local failure rate was 0% in patients with pCR vs 11.7% (95% CI, 3.6%-25.1%) and 9.1% (95% CI, 3.3%-18.5%) for patients with less than pCR in 9514 and 0630, respectively. Histologic types other than leiomyosarcoma, liposarcoma, and myxofibrosarcoma were associated with worse OS (HR, 2.24; 95% CI, 1.12-4.45).Conclusions and Relevance:This ancillary analysis of 2 nonrandomized clinical trials found that pCR was associated with improved survival in patients with STS and should be considered as a prognostic factor of clinical outcomes for future studies.Trial Registration:ClinicalTrials.gov Identifiers: RTOG 0630 (NCT00589121); RTOG 9514 (NCT00002791).

In an era of increasing virtual communication, we aimed to investigate current formats used by radiation oncology residents for reviewing radiation treatment plans with attendings, preferences for formats, and reasons contributing to preferences. Residents enrolled in Canadian radiation oncology programs received questionnaires examining training level, typical review formats, preferred format, and reasons for preference. Analysis excluded PGY-1s due to insufficient exposure. Fifty-two residents participated. National response rate was 55%. Overall, hybrid review was the most used format (77%). Virtual review was the most preferred format (44%). Preference for virtual review was most common among junior residents (57%), while in-person review was most preferred by senior residents (45.4%). Few residents typically use their preferred format (35%). Reasons for preference varied between groups in convenience (p < 0.01), interactivity (p < 0.01), and teaching quality (p = 0.04). The persistence of e-learning suggests that virtual treatment planning education will continue to some degree. Junior residents prefer virtual review, while a clearly preferred review format was less apparent among senior residents. Preferences are multifactorial, and the trends seen in reasons for preference between formats may reflect advantages inherent to each. Progress is still needed in optimizing treatment planning education, as suggested by few residents using their preferred format. Residents and staff should collectively decide which educational format for treatment planning best meets educational needs.

131 Background: Pre-clinical evidence suggest that statins have antiproliferative, proapoptotic, and anti-invasive properties. Also, statins can sensitize cancer tissues and protect normal tissues to the effects of radiation. A standard treatment of locally advanced rectal cancer (LARC) involves neoadjuvant CRT followed by surgery and adjuvant chemotherapy. Retrospective analyses of statin use in rectal cancer patients receiving CRT suggest a higher pathological complete response rate (pCRr). Methods: Patients with clinical stage II-III rectal adenocarcinoma, within 5 cm of the anal verge (AV) or less than 12cm from the AV with threatened circumferential resection margin were treated with rosuvastatin 40 mg daily starting 2 weeks prior to the start and until 4 weeks after the end of CRT. The primary objective of the study was pCRr. Secondary objectives included, near-CRr, Ro resection rate (RR), sphincter preservation, 3-year relapse free survival (RFS), 3-year overall survival (OS), toxicity and safety. A Simon’s minimax two-stage design was used to determine significance. A pCRr of ≥25% was required to reject the null hypothesis. RFS and OS rates were calculated using the Kaplan-Meier product-limit method. Results: Forty-five patients were enrolled from 2016 to 2021. Sixty-seven percent were male with a median age of 54 (IQR 37- 61), 97.8% (44/45) had ECOG PS of 0-1, 15.6% (7/45) were cT4, 73.3% (33/45) were cN+. Of the 38 evaluable patients, 9 had a pCR (23.7%), an additional 9 had a near-pCR (23.7%). With a median follow-up of 3.26 years, the 3-year OS rate was 96.3% (95% CI (0.765, 0.995)) and the 3-year DFS rate was 77.9% (95% CI (0.604, 0.883)) in the evaluable patients. One patient elected for non-operative management and has an on-going clinical CR for the last 15 months. Surgery was sphincter sparing in 17 patients (43.6%) and an 87.2% Ro RR was observed. Toxicities attributable to rosuvastatin included: two patients with elevations in liver enzymes, grade 3. Remaining toxicities were grade 2 or less, with the most common toxicities being fatigue (n = 5) and pain (n = 3). Only 2 patients experienced CPK elevations, both grade 2. Conclusions: The addition of rosuvastatin to nCRT resulted in a considerable complete and near-complete response rate with an acceptable toxicity profile. Rosuvastatin treatment should be studied further in the total neoadjuvant and non-operative management settings for locally advanced rectal cancer. Clinical trial information: NCT02569645 .

Aim: To determine the efficacy of preoperative chemoradiotherapy as per the CROSS protocol for oesophageal/gastroesophageal junction cancer (OEGEJC), when expanded to patients outside of the inclusion/exclusion criteria defined in the original clinical trial. Materials and methods: Data were collected retrospectively on 229 OEGEJC patients referred for curative-intent preoperative chemoradiotherapy. Outcomes including pathological complete response (pCR), overall survival (OS), cancer-specific survival and recurrence-free survival (RFS) of patients who met CROSS inclusion criteria (MIC) versus those who failed to meet criteria (FMIC) were determined. Results: In total, 42.8% of patients MIC, whereas 57.2% FMIC; 16.6% of patients did not complete definitive surgery. The MIC cohort had higher rates of pCR, when compared with the FMIC cohort (33.3% versus 20.6%, P = 0.039). The MIC cohort had a better RFS, cancer-specific survival and OS compared with the FMIC cohort (P = 0.006, P = 0.004 and P = 0.009, respectively). Age >75 years and pretreatment weight loss >10% were not associated with a poorer RFS (P = 0.541 and 0.458, respectively). Compared with stage I-III patients, stage IVa was associated with a poorer RFS (hazard ratio (HR) = 2.158; 95% confidence interval (CI) = 1.339-3.480, P = 0.001). Tumours >8 cm in length or >5 cm in width had a trend towards worse RFS (HR = 2.060; 95% CI = 0.993-4.274, P = 0.052). Conclusion: Our study showed that the robust requirements of the CROSS trial may limit treatment for patients with potentially curable OEGEJC and can be adapted to include patients with a good performance status who are older than 75 years or have >10% pretreatment weight loss. However, the inclusion of patients with celiac nodal metastases or tumours >8 cm in length or >5 cm in width may be associated with poor outcomes. Crown Copyright (C)2022 Published by Elsevier Ltd on behalf of The Royal College of Radiologists. All rights reserved.

Objectives: Nonoperative management (NOM) of locally advanced rectal cancer is an emerging approach allowing patients to preserve their anal sphincter. Identifying clinical factors associated with pathologic complete response (pCR) is essential for physicians and patients considering NOM. Materials and Methods: In total, 412 locally advanced rectal cancer patients were included in this retrospective analysis. Tumor volumes were derived from pretreatment MRI. Clinical parameters such as tumor volume, stage, and location were analyzed by univariate and multivariate analysis, against pCR. A receiver operator characteristic curve was generated to identify a tumor volume cut-off with the highest clinically relevant Youden index for predicting pCR. Results: Seventy-five of 412 patients (18%) achieved pCR. A tumor volume threshold of 37.3 cm(3) was identified as predictive for pCR. On regression analysis, a tumor volume >37.3 cm(3) was associated with a greater than 78% probability of not achieving pCR. On multivariate analysis, a GTV <37.3 cm(3) [odds ratio (OR)=3.7, P<0.0001] was significantly associated with an increased pCR rate, whereas tumor length > 4.85 cm was associated with pCR on univariate (OR=3.03, P<0.01) but not on multivariate analysis (OR=1.45, P=0.261). Other clinical parameters did not impact pCR rates. Conclusions: A tumor volume threshold of 37.3 cm(3) was identified as predictive for pCR in locally advanced rectal cancer patients receiving neoadjuvant chemoradiation. Tumors above this volume threshold corresponded to a greater than 78% probability of not achieving pCR. This information will be helpful at diagnosis for clinicians who are considering potential candidates for NOM.

AIMS:18F-fluorodeoxyglucose positron emission tomography/computed tomography (18FDG-PET/CT) is routinely used for the pre-treatment staging of oesophageal or gastro-oesophageal junction cancers (EGEJC). The aim of this study was to identify objective 18FDG-PET/CT-derived parameters that can aid in predicting the patterns of recurrence and prognostication in patients with EGEJC. PATIENTS AND METHODS:EGEJC patients referred for consideration of preoperative chemoradiation therapy were identified and clinicopathological data were collected. 18FDG-PET/CT imaging data were reviewed and correlated with treatment outcomes. Maximum standardised uptake value (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis were assessed and association with recurrence-free survival (RFS), locoregional recurrence-free survival (LR-RFS), oesophageal cancer-specific survival (ECSS) and overall survival were evaluated using receiver operating characteristic curves, as well as Cox regression and Kaplan-Meier models. RESULTS:In total, 191 EGEJC patients completed trimodality treatment and 164 with 18FDG-PET/CT data were included in this analysis. At the time of analysis, 15 (9.1%), 70 (42.7%) and two (1.2%) patients were noted to have locoregional, distant and both locoregional and distant metastases, respectively. The median RFS was 30 months (9.6-50.4) and the 5-year RFS was 31.1%. The 5-year overall survival and ECSS were both noted to be 34.8%. Pre-treatment MTV25 > 28.5 cm3 (P = 0.029), MTV40 > 12.4 cm3 (P = 0.018) and MTV50 > 10.2 cm3 (P = 0.005) predicted for worse LR-RFS, ECSS and overall survival for MTV definition of voxels ≥25%, 40% and 50% of SUVmax. CONCLUSION:18FDG-PET/CT parameters MTV and total lesion glycolysis are useful prognostic tools to predict for LR-RFS, ECSS and overall survival in EGEJC. MTV had the highest accuracy in predicting clinical outcomes. The volume cut-off points we identified for different MTV thresholds predicted outcomes with significant accuracy and may potentially be used for decision making in clinical practice.

BACKGROUND: Radiation dose schedules for neoadjuvant chemoradiation for rectal cancers differ, with the most common dose schedule using 5040 cGy in 28 fractions. OBJECTIVES: The aim of this retrospective study was to assess the benefit of higher radiation doses beyond 5040 cGy in the context of pathological response and follow-up events. SETTING: The database from a provincial tertiary cancer center in Canada was the source of information for this study. PATIENTS: Included in this study were 508 consecutive patients with rectal cancer with locally advanced disease (clinical T3/T4 or N1/N2) who received neoadjuvant chemoradiation followed by surgery. Of the 508 patients, 281 received the standard radiation dose of 4500 to 5040 cGy and 227 received a dose >5040 cGy. MAIN OUTCOME MEASURE: The postsurgical pathology, late toxicities, and follow-up outcomes were analyzed. The outcomes were evaluated in relation to the dose of radiation received. RESULTS: Data regarding the clinical outcomes were comparable between the 4500 to 5040 cGy and >5040 cGy radiation groups with pathological complete response rates of 20.9% and 15.4% (p = 0.104); distant recurrence rates of 17.4% and 19.4% (p = 0.36); local recurrence rates of 3.2% and 3.5% (p = 0.36); and the median overall survival rates of 61 and 60.5 months (p = 0.8). No statistically significant correlation of improvement in outcomes was noted with radiation doses beyond 5040 cGy. LIMITATIONS: This is a retrospective study. CONCLUSION: Our study showed that dose escalation beyond the standard dose of 4500 to 5040cGy failed to achieve meaningful clinical outcomes. See Video Abstract at http://links.lww.com/DCR/B633. MÁS NO ES MEJOR CUANDO SE TRATA DE TRATAR EL CÁNCER DE RECTO CON QUIMIORRADIACIÓN MULTIMODAL MÁS ALLÁ DE LA DOSIS DE RADIACIÓN ESTÁNDAR DE 5040 CGY ANTECEDENTES: En neoadyuvancia de cáncer rectal es posible encontrar muchas variaciones, en radioterapia la dosis más común que usa 5040 cGy en 28 fracciones. OBJETIVOS: El objetivo de este estudio retrospectivo fue evaluar el beneficio de dosis de radiación más altas más allá de 5040cGy en el contexto de la respuesta patológica y en su seguimiento. AJUSTE: Base de datos de un centro de cáncer terciario provincial en Canadá. PACIENTES: Se incluyeron en este estudio quinientos ocho pacientes consecutivos con cáncer de recto y enfermedad localmente avanzada (clínica T3 / T4 o N1 / N2) que recibieron quimiorradiación neoadyuvante seguida de cirugía. De los 508 pacientes, 281 recibieron la dosis de radiación estándar de 4500-5040 cGy y 227 recibieron una dosis > 5040 cGy. PRINCIPAL MEDIDA DE RESULTADO: Se analizo evolucion posquirúrgica, toxicidad tardía y seguimiento. Los resultados se evaluaron en relación con la dosis de radiación recibida. RESULTADOS: Los datos con respecto a los resultados clínicos fueron comparables entre los grupos de radiación de 4500-5040 cGy y> 5040 cGy con tasas de respuesta patológica completa de 20,9% y 15,4% respectivamente (p = 0,104); tasas de recurrencia a distancia de 17,4% y 19,4%, respectivamente (p = 0,36); tasas de recurrencia local de 3,2% y 3,5%, respectivamente (p = 0,36); y la mediana de las tasas de supervivencia global de 61 y 60,5 meses, respectivamente (p = 0,8). No se observó una correlación estadísticamente significativa de mejoría en los resultados con dosis de radiación superiores a 5040 cGy. LIMITACIONES: Este es un estudio retrospectivo. CONCLUSIONES: Nuestro estudio mostró que el aumento de la dosis más allá de la dosis estándar de 4500–5040cGy no logró resultados clínicos significativos. Consulte Video Resumen en http://links.lww.com/DCR/B633. (Traducción—Dr. Gunther Bocic)