RESUMEN
OBJECTIVE: To evaluate the management and oncological outcomes of rectal cancer patients with local regrowth in a watch-and-wait (W&W) program. BACKGROUND: Approximately 15%-30% of patients with a clinical complete response after (chemo) radiotherapy who undergo a W&W policy will experience a local regrowth. The risks of these local regrowths have not yet been fully established and main concerns include high postoperative morbidity, requirement of advanced surgery, and pelvic recurrence after regrowth treatment. METHODS: All patients with a local regrowth after an initial W&W approach between January 2005 and March 2018 were retrospectively identified from 2 cohorts of rectal cancer patients with a clinical complete response after (chemo) radiotherapy. Type and outcome of regrowth treatment were assessed. Oncological outcome was assessed using Kaplan-Meier estimates. RESULTS: Eighty-nine out of 385 patients developed a local regrowth after a median of 9 (interquartile range 7-14) months. Median follow-up time was 28 (interquartile range 19-41) months. Eighty-four (94%) patients underwent surgical treatment of the local regrowth: total mesorectal excision was performed in 58 out of 84 (69%) patients and local excision was performed in 26 (31%) patients. The 2-year local recurrence-free rate, distant metastasis-free rate, disease-free survival, and overall survival in the patients undergoing surgical treatment were 97.8%, 91.8%, 90.3%, and 98.4%, respectively. CONCLUSION: The vast majority (97%) of patients with regrowth after a W&W policy were able to undergo treatment with curative intent for local regrowth. Uncontrolled pelvic disease was very rare.
Asunto(s)
Recurrencia Local de Neoplasia , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Adulto , Anciano , Anciano de 80 o más Años , Quimioradioterapia , Colonoscopía , Terapia Combinada , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Tasa de Supervivencia , Espera VigilanteRESUMEN
OBJECTIVE AND BACKGROUND: Watch-and-wait approach in rectal cancer relies on the identification of a clinical complete response (CR) after neoadjuvant (chemo)radiotherapy. This is mainly performed by rectal examination, magnetic resonance imaging, and endoscopy. Endoscopy has been less well studied, and the objective of the study is to assess the diagnostic value of endoscopy and the predictive value of endoscopic features for the identification of CR. PATIENTS AND METHODS: A total of 161 patients with primary rectal cancer undergoing flexible sigmoidoscopy for response assessment after neoadjuvant (chemo)radiotherapy between January 2012 and December 2015 at a single institution were evaluated retrospectively. Three independent readers scored endoscopic features and a confidence level score for a CR. Diagnostic performance of endoscopy and positive predictive value (PPV) of endoscopic features for a CR were calculated. If available, biopsy results were revealed to the reader and a change in confidence level was noted. Reference standard was histology after surgery, or long-term outcome in a watch-and-wait policy. RESULTS: Median time to endoscopy was 9 (interquartile range 8-12) weeks. Area under the receiver operator characteristic curve, sensitivity, specificity, PPV, and negative predictive value for a CR were 0.80 to 0.84, 72% to 94%, 61% to 85%, 63% to 78% and 80% to 89%, respectively. A flat scar was the most predictive feature of a CR (PPV 70%-80%). The PPV of small flat ulcers and large flat ulcers were 40% to 50% and 29% to 33%, respectively. The addition of biopsy results led to a significant change in confidence level score in 4% to 13% of patients. CONCLUSIONS: More than 70% of the patients with a luminal CR after neoadjuvant treatment for rectal cancer can be identified by endoscopy at ±9 weeks. Together with findings on digital rectal examination (DRE) and magnetic resonance imaging, specific endoscopic features can be used to select patients for an extended observation period to select for organ preservation.
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Quimioradioterapia , Endoscopía Gastrointestinal , Terapia Neoadyuvante , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Anciano , Biopsia , Tacto Rectal , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Neoplasias del Recto/diagnóstico por imagen , Estudios RetrospectivosRESUMEN
OBJECTIVE: The aim of this study was to evaluate whether magnetic resonance imaging (MRI) can accurately identify poor responders after chemoradiotherapy (CRT) who will need to go straight to surgery, and to evaluate whether results are reproducible among radiologists with different levels of expertise. METHODS: Seven independent readers with different levels of expertise retrospectively evaluated the restaging MRIs (T2-weighted + diffusion-weighted imaging [T2W + DWI]) of 62 patients and categorized them as (1) poor responders - highly suspicious of tumor; (2) intermediate responders - tumor most likely; and (3) good - potential (near) complete responders. The reference standard was histopathology after surgery (or long-term follow-up in the case of a watch-and-wait program). RESULTS: Fourteen patients were complete responders and 48 had residual tumor. The median percentage of patients categorized by the seven readers as 'poor', 'intermediate', and 'good' responders was 21% (range 11-37%), 50% (range 23-58%), and 29% (range 23-42%), respectively. The vast majority of poor responders had histopathologically confirmed residual tumor (73% ypT3-4), with a low rate (0-5%) of 'missed complete responders'. Of the 14 confirmed complete responders, a median percentage of 71% were categorized in the MR-good response group and 29% were categorized in the MR-intermediate response group. CONCLUSIONS: Radiologists of varying experience levels should be able to use MRI to identify the ± 20% subgroup of poor responders who will definitely require surgical resection after CRT. This may facilitate more selective use of endoscopy, particularly in general settings or in centers with limited access to endoscopy.
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Neoplasias , Preservación de Órganos , Quimioradioterapia , Humanos , Imagen por Resonancia Magnética , Terapia Neoadyuvante , Neoplasias/diagnóstico por imagen , Neoplasias/cirugía , Neoplasias/terapia , Selección de Paciente , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
OBJECTIVES: Rectal cancer patients with a clinical complete response after chemoradiotherapy (CRT) may be followed with a 'watch-and-wait' (W&W) approach as an alternative to surgery. MRI plays an important role in the follow-up of these patients, but basic knowledge on what to expect from the morphology of the irradiated tumour bed during follow-up is lacking, which can hamper image interpretation. The objective was to establish the spectrum of non-suspicious findings during long-term (> 2 years) follow-up in patients with a sustained clinical complete response undergoing W&W. METHODS: A total of 1509 T2W MRIs of 164 sustained complete responders undergoing W&W were retrospectively evaluated. Morphology of the tumour bed was evaluated (2 independent readers) on the restaging MRI and on the various follow-up MRIs and classified as (a) no fibrosis, (b) minimal fibrosis, (c) full thickness fibrosis, or (d) irregular fibrosis. Any changes occurring during follow-up were documented. RESULTS: A total of 104 patients (63%) showed minimal fibrosis, 38 (23%) full thickness fibrosis, 8 (5%) irregular fibrosis, and 14 (9%) no fibrosis. In 93% of patients, the morphology remained completely stable during follow-up; in 7%, a minor increase/decrease in fibrosis was observed. Interobserver agreement was excellent (κ 0.90). CONCLUSIONS: Typically, the morphology as established at restaging remains completely unchanged. The majority of patients show fibrosis with the predominant pattern being a minimal fibrosis confined to the rectal wall. Complete absence of fibrosis occurs in only 1/10 cases. Once validated in independent cohorts, these findings may serve as a reference for radiologists involved in the clinical follow-up of W&W patients. KEY POINTS: ⢠In rectal cancer patients with a sustained complete response after chemoradiation, the rectal wall morphology as established on restaging MRI typically remains unchanged during long-term MRI follow-up. ⢠The vast majority of complete responders show fibrosis with the predominant pattern being a minimal fibrotic remnant that remains confined to the rectal wall; complete absence of fibrosis occurs in only 10% of the cases. ⢠Once validated in independent cohorts, the findings of this study may serve as a reference for radiologists involved in the clinical follow-up of rectal cancer patients undergoing watch-and-wait.
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Imagen por Resonancia Magnética/métodos , Neoplasias del Recto/diagnóstico por imagen , Espera Vigilante/métodos , Adulto , Anciano , Anciano de 80 o más Años , Quimioradioterapia , Femenino , Fibrosis , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/patología , Neoplasias del Recto/patología , Recto/patología , Inducción de Remisión , Estudios RetrospectivosRESUMEN
BACKGROUND: Little is known about the costs of the current treatment strategy in locally advanced rectal cancer, in which patients with a clinical complete response after chemoradiotherapy are treated in a watch-and-wait policy. OBJECTIVE: The aim of this study is to present the oncological outcome and hospital costs of patients with a complete response after chemoradiotherapy (watch-and-wait policy) and patients with an incomplete response after chemoradiotherapy (total mesorectal excision). DESIGN: This was a cohort study. SETTINGS: This study was conducted at an academic and a nonacademic hospital. PATIENTS: Patients with locally advanced rectal cancer received either a watch-and-wait policy or total mesorectal excision depending on their clinical response to chemoradiotherapy. INTERVENTIONS: Watch-and-wait policy and total mesorectal excision were the treatments applied. MAIN OUTCOME MEASURES: The primary outcomes measured were overall, local recurrence-free, and distant metastasis-free survival and hospital costs over a 2-year follow-up period. RESULTS: A total of 292 patients with locally advanced rectal cancer were included. Mean age was 65.1 years, and 64.7% were men. One hundred five patients were included in the watch-and-wait subgroup, and 187 patients were in the total mesorectal excision subgroup. Both subgroups showed good oncological outcomes. Hospital costs consisted of 5 categories: costs of primary surgery, costs of adjuvant chemotherapy, costs of examinations, costs of additional surgery, and costs of treatment of regrowth/metastasis. The mean costs per patient were &OV0556;6713 (watch-and-wait subgroup) and &OV0556;17,108 (total mesorectal excision subgroup) over the first 2 years. LIMITATIONS: This study was limited by the following: costs were only from a hospital perspective, follow-up was 2 years, the study was retrospective in part, and there was no comparative study. CONCLUSIONS: Overall survival was good in both subgroups and comparable to literature. The mean costs per patient differ between the watch-and-wait subgroup (&OV0556;6713) and the total mesorectal excision subgroup (&OV0556;17,108). No comparison between the groups could be made. Based on the results of this study, the current strategy, where patients with a clinical complete response are treated in a watch-and-wait policy, and patients with an incomplete response are treated with total mesorectal excision, is likely to be (cost)saving. See Video Abstract at http://links.lww.com/DCR/B177. RESULTADOS ONCOLÓGICOS Y COSTOS HOSPITALARIOS EN EL TRATAMIENTO DE PACIENTES CON CANCER DE RECTO: ACTITUD DE ESPERA-VIGILANCIA Y TRATAMIENTO QUIRÚRGICO ESTANDARD: Se sabe poco sobre el costo del tratamiento actual en casos de cancer de recto localmente avanzado, cuando se aplica una política de vigilancia y espera en aquellos pacientes que presentan una respuesta clínica completa después de radio-quimioterapia.El propósito final del presente estudio es dar a conocer el resultado oncológico y los costos hospitalarios de los pacientes que presentan una respuesta clínica completa después de radio-quimioterapia (actitud de vigilancia-espera) y los pacientes con una respuesta incompleta después luego de radio-quimioterapia (excisión total del mesorrecto-ETM).Estudio de cohortes.Hospitales académicos y no académicos.Todos aquellos pacientes tratados por un cáncer de recto localmente avanzado y que fueron seguidos con una política de vigilancia y espera o la ETM, en función de la respuesta clínica a la radio-quimioterapia.Políticas de vigilancia-espera, excisión total del mesorrecto.Sobrevida global libre de recurrencia local, metástasis a distancia, sobrevida libre de enfermedad y costos hospitalarios durante un período de seguimiento de dos años.Se incluyeron 292 pacientes diagnosticados de cancer de recto localmente avanzado. La edad media fue de 65,1 años, 64,7% eran de sexo masculino. Se incluyeron 105 pacientes en el subgrupo de vigilancia-espera, y 187 en el subgrupo de excisión total del mesorrecto. Ambos subgrupos mostraron optimos resultados oncológicos. Los costos hospitalarios se dividieron en cinco categorías: costos de cirugía primaria; costos de quimioterapia adyuvante; costos de exámenes; costos de cirugía adicional; y costos del tratamiento de rebrote / metástasis. Los costos medios por paciente fueron de &OV0556; 6.713 (subgrupo de espera-vigilancia) y &OV0556; 17.108 (subgrupo de excisión total del mesorrecto) durante los primeros dos años.Analisis de costos desde una perspectiva hospitalaria durante un seguimiento de dos años, estudio parcialmente retrospectivo, no comparativo.La sobrevida general fue optima en ambos subgrupos y comparable con la literatura. El costo promedio por paciente difiere entre el subgrupo de vigilancia y espera (&OV0556; 6.713) con el subgrupo de la ETM(&OV0556; 17.108). No se pudieron comparar definitivamente ambos grupos. Basados en los resultados del presente estudio, es probable que la estrategia actual, en la que los pacientes con respuesta clínica completa sean tratados con una política de vigilancia y espera, presenten muy probablemente un cierto ahorro en el costo con relación a los pacientes con una respuesta incompleta tratados con excisión total del mesorrecto. Consulte Video Resumen en http://links.lww.com/DCR/B177. (Traducción-Dr. Xavier Delgadillo).
Asunto(s)
Costos de Hospital , Proctectomía/economía , Neoplasias del Recto/terapia , Espera Vigilante/economía , Anciano , Quimioradioterapia/economía , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: To assess whether extending the observation period in patients with a near clinical complete response (near cCR) after chemoradiation (CRT) leads to an impaired oncological outcome. METHODS: Patients who had a clinical complete response (cCR) 8-10 weeks after CRT restaging with magnetic resonance imaging and endoscopy were offered a watch-and-wait strategy (W&W1), while patients with a near cCR were offered to undergo local excision or a second restaging 6-12 weeks later. Patients who achieved a cCR at the second restaging were also offered a watch-and-wait strategy (W&W2). RESULTS: Overall, 102 patients with a cCR at the first restaging immediately entered the W&W1, while the remaining 68 patients had a near cCR: 19 patients underwent transanal endoscopic microsurgery and 49 patients opted for a second restaging. Additionally, 44/49 (90%) patients showed a cCR at the second restaging and entered the W&W2. Patients in the W&W1 group had a 2-year local regrowth-free rate (LRFR) of 84% and 2-year overall survival (OS) of 99%, while patients in the W&W2 group had a 2-year LRFR of 73% and OS of 98% (p > 0.05). Multivariable Cox regression analyses showed that late inclusion was not a significant predictive factor for higher risk of LR or lower non-regrowth disease-free survival. CONCLUSIONS: Overall, 90% of patients with a near cCR 8-10 weeks after CRT will proceed to a cCR 6-12 weeks later; therefore, it seems logical to extend the observation period rather than to proceed to surgery. Although there is a non-significant increase in local regrowth rate in these patients, it does not seem to impact the oncological outcome.
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Tratamientos Conservadores del Órgano , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Microcirugía Endoscópica Transanal , Espera Vigilante , Anciano , Quimioradioterapia , Supervivencia sin Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Proctoscopía , Supervivencia sin Progresión , Neoplasias del Recto/diagnóstico por imagen , Tasa de Supervivencia , Factores de TiempoRESUMEN
Importance: A watch-and-wait approach for patients with rectal cancer and a clinical complete response after neoadjuvant chemoradiotherapy or radiotherapy is associated with better quality of life and functional outcome. Nevertheless, prospective data on both parameters are scarce. Objective: To prospectively evaluate quality of life and functional outcome, including bowel, urinary, and sexual function, of patients following a watch-and-wait approach. Design, Setting, and Participants: A total of 278 patients with rectal cancer and a clinical complete response or near-complete response after neoadjuvant chemoradiotherapy or radiotherapy were included in 2 prospective cohort studies: a single-center study (March 2014 to October 2017) and an ongoing multicenter study (from September 2017). Patients were observed by a watch-and-wait approach. Additional local excision or total mesorectal excision was performed for residual disease or regrowth. Data were analyzed between April 1, 2021, and August 27, 2021, for patients with a minimum follow-up of 24 months. Main Outcomes and Measures: Quality of life was evaluated with the European Organisation for Research and Treatment of Cancer-Quality of Life Questionnaire-C30 (EORTC-QLQ-C30), EORTC-QLQ-CR38, or EORTC-QLQ-CR29 and 36-Item Short-Form Health Survey. The score for the questionnaires and 36-Item Short-Form Health Survey ranges from 0 to 100. For some scales, a high score indicates a high level of functioning, and for others it indicates a high level of complaints and symptomatology. Functional outcome was assessed by the Low Anterior Resection Syndrome score, Vaizey incontinence score, International Prostate Symptom Score, International Index of Erectile Function, and Female Sexual Function Index. Results: Of 278 patients included, 187 were male (67%), and the median age was 66 years (range, 34-85 years). In the first 24 months, 221 patients (80%) were observed by a watch-and-wait approach without requiring surgery, 18 patients (6%) underwent additional local excision, and 39 patients (14%) underwent total mesorectal excision. In general, patients observed by a watch-and-wait approach reported good quality of life, with limited variation over time. At 3 months, 56 of 221 patients (25.3%) reported major bowel dysfunction; at 12 months, 53 patients (24.0%) reported it; and at 24 months, 55 patients (24.9%) reported it. At 24 months, 48 of 151 male patients (31.8%) reported severe erectile dysfunction. For female patients, sexual satisfaction and overall sexual function decreased during follow-up. Patients who underwent local excision reported more major bowel dysfunction (10 of 18 patients [55.6%]) compared with those without additional surgery. Quality-of-life scores, however, were comparable. After total mesorectal excision, patients scored significantly worse on several quality-of-life subscales. Conclusions and Relevance: Results of this study suggest that patients with rectal cancer who were observed by a watch-and-wait approach had good quality of life, with some patients reporting bowel and sexual dysfunction. Quality of life and functional outcome deteriorated when patients required surgery. These data will be useful in daily care to counsel patients on what to expect from a watch-and-wait approach.
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Procedimientos Quirúrgicos del Sistema Digestivo , Neoplasias del Recto , Humanos , Masculino , Femenino , Anciano , Neoplasias del Recto/cirugía , Neoplasias del Recto/diagnóstico , Estudios Prospectivos , Calidad de Vida , Complicaciones Posoperatorias , Terapia Neoadyuvante/métodosRESUMEN
INTRODUCTION: Several factors are included in decision making for treatment of patients with locally advanced rectal cancer, including a trade-off between risks and gains of both clinical and functional outcomes. However, it is largely unknown which outcomes are most important to patients and whether this differs between patients and clinicians. METHODS: Both clinicians and patients treated for locally advanced rectal cancer were invited to fill out an online questionnaire, including a choice-based conjoint experiment. Participants were presented 14 comparisons of two hypothetical case presentations, characterized by different treatments and outcomes of care (6 attributes) and were asked to select the case with the best outcome at that moment. Hierarchical Bayes Estimation was used to calculate the relative importance (RI) of each of the six attributes. RESULTS: In total, 94 patients and 128 clinicians completed the questionnaire. For patients, avoiding surgery with permanent stoma was most important (RI 24.4, 95%CI 21.88-26.87) and a 2-year difference in disease-free survival was least important (RI 5.6, 95%CI 4.9-6.2). Clinicians assigned highest importance to avoiding severe and daily worries about cancer recurrence (RI 30.7, 95%CI 29.1-32.4), while this was ranked 4th by patients (RI 17.9, 95%CI 16.5-19.4, p < 0.001). CONCLUSION: When confronted with different outcomes within one case description, patients find the duration of disease free survival the least important. In addition, considerable differences were found between the importance assigned by patients and clinicians to clinical and functional outcomes, most notably in avoiding surgery with permanent stoma and worries about recurrence.
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Actitud Frente a la Salud , Conducta de Elección , Supervivencia sin Enfermedad , Prioridad del Paciente , Médicos , Calidad de Vida , Neoplasias del Recto/terapia , Adulto , Anciano , Quimioradioterapia , Colostomía , Incontinencia Fecal , Femenino , Gastroenterólogos , Humanos , Masculino , Persona de Mediana Edad , Oncólogos , Medición de Resultados Informados por el Paciente , Complicaciones Posoperatorias , Proctectomía , Disfunciones Sexuales Fisiológicas , Cirujanos , Encuestas y Cuestionarios , Incontinencia Urinaria , Espera VigilanteRESUMEN
BACKGROUND AND PURPOSE: To assess the long-term anorectal function in rectal cancer patients following a watch-and-wait policy after chemoradiotherapy and to investigate the dose-volume effects of radiotherapy on the anorectal function. METHODS AND MATERIALS: Thirty-three patients with primary rectal cancer who were treated with chemoradiotherapy and a watch-and-wait policy with minimum follow-up of 2⯠years were included. We assessed the anorectal function using anorectal manometry and patient reported outcomes (Vaizey and LARS score). Dose-volume histograms were calculated for the rectum and anal sphincter complex, and associations between the dose-volume parameters and anorectal function were assessed. RESULTS: Dmean to the rectum and anal sphincter complex was 50.5â¯Gy and 44.7â¯Gy, respectively. After a median follow-up of 38 (range 23-116) months, 33.3% of the patients reported major LARS. Mean LARS score was 23.4⯱â¯11.3 and mean Vaizey score was 4.3⯱â¯4.1. The most frequent complaints were clustering of defaecation and faecal urgency. Trends towards a higher Vaizey and LARS score after higher anal sphincter complex dose were observed, although these associations were not statistically significant. CONCLUSIONS: This is the first study to investigate the late dose-volume effects of radiotherapy specifically on the anorectal function in rectal cancer patients. One-third of the patients had major LARS and the most frequent reported complaints were clustering and faecal urgency. Additionally, we observed trends towards worse long-term anorectal function after higher anal sphincter complex radiotherapy dose. However, this should be evaluated on a larger scale. Future efforts to minimise the dose to the sphincters could possibly reduce the impact of radiotherapy on the anorectal function.
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Canal Anal/efectos de la radiación , Neoplasias del Recto/radioterapia , Recto/efectos de la radiación , Adulto , Anciano , Anciano de 80 o más Años , Canal Anal/diagnóstico por imagen , Canal Anal/fisiopatología , Quimioradioterapia , Estudios de Cohortes , Relación Dosis-Respuesta en la Radiación , Incontinencia Fecal/etiología , Incontinencia Fecal/fisiopatología , Femenino , Humanos , Masculino , Manometría/métodos , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Traumatismos por Radiación/etiología , Traumatismos por Radiación/fisiopatología , Planificación de la Radioterapia Asistida por Computador , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/patología , Recto/diagnóstico por imagen , Recto/fisiopatología , Espera VigilanteRESUMEN
PURPOSE: To evaluate what features on restaging MRI and endoscopy led to a false clinical diagnosis of residual tumour in patients with a pathological complete response after rectal cancer surgery. METHODS: Patients with an unrecognized complete response after (chemo)radiotherapy were selected in a tertiary referral centre for rectal cancer treatment. An unrecognized complete response was defined as a clinical incomplete response at MRI and/or endoscopy with a pathological complete response of the primary tumour after surgery. The morphology of the tumour bed and the lymph nodes were evaluated on post-CRT T2-weighted MRI (T2-MRI) and diffusion weighted imaging (DWI). Post-CRT endoscopy images were evaluated for residual mucosal abnormalities. MRI and endoscopy features were correlated with histopathology. RESULTS: Thirty-six patients with an unrecognized complete response were included. Mucosal abnormalities were present at restaging endoscopy in 84%, mixed signal intensity on T2-MRI in 53%, an irregular aspect of the former tumour location on T2-MRI in 69%, diffusion restriction on DWI in 51% and suspicious lymph nodes in 25%. CONCLUSIONS: Overstaging of residual tumour after (chemo)radiotherapy in rectal cancer is mainly due to residual mucosal abnormalities at endoscopy, mixed signal intensity or irregular fibrosis at T2-MRI, diffusion restriction at DWI and residual suspicious lymph nodes. Presence of these features is not definitely associated with residual tumour and in selected cases an extended waiting interval can be considered.