Clinical Complete Responders Research Articles

Comparing outcomes and cost in surgery versus watch & wait surveillance of patients with rectal cancer post neoadjuvant long course chemoradiotherapy.

Watch and wait (W&W) in complete clinical responders after neoadjuvant chemoradiotherapy has increasingly robust data supporting its oncological safety. Recently, studies have assessed the real-world costs of this strategy compared to surgical resection. Our aim was to compare our oncological safety and costs associated with operative and surveillance strategies to international literature. Data were retrospectively collected and analysed via electronic health records from March 2014 to March 2021 in Christchurch, New Zealand. Two cohorts were created based on intention to treat. All hospital events were recorded and costed, as well as oncologic outcomes. Our primary endpoints were the cumulative cost of both strategies, 3-year survival rate, and disease-free survival. Forty-eight patients were identified who had rectal cancers resected (OT) with a yPT0N0 pathology, and 42 who were on the wait-and-watch (W&W) audit after having a clinical complete response. After exclusions, we identified 38 OT and 23 W&W patients; the W&W group were more co-morbid (P = 0.05), had worse functional status (P = 0.008), higher BMI (P = 0.34) and more favourable clinical tumour staging (P = 0.01). The operative treatment (OT) group (n = 38) had more acute admissions (34% versus 13% in W&W, P = 0.08, OR 0.29). There was a 35.7% (n = 8 of 23) local recurrence in W&W and none in the OT group (P ≤ 0.001), with successful salvage in the W&W with local recurrence in 71.5% (n = 5 of 7). Three-year distant metastasis-free rate was 97.3% in the OT group and 90.9% in W&W (p = 0.05). Overall survival was 100% (W&W) and 94.7% (OT); (P = 0.019). Care in the OT group cost more than W&W, accounting for local regrowth management; $NZ70,759.56 versus $NZ47,905.52 (P = 0.014). This study found better oncological outcomes in the OT group, whilst the W&W group had reduced morbidity and acute bed days. The cost of wait and watch was approximately two-thirds that of operative treatment, even accounting for salvage procedures for local regrowth.

Active surveillance for clinical complete responders after chemoradiotherapy for oesophageal squamous cell carcinoma.

Guidelines on the treatment of oesophageal squamous cell carcinoma (SCC) recommend neoadjuvant chemoradiotherapy plus surgery or definitive chemoradiotherapy. The aim of this study was to evaluate the outcome of patients with a cCR after chemoradiotherapy who underwent active surveillance. Patients with oesophageal SCC who were treated with chemoradiotherapy between January 2016 and June 2022 were identified from an institutional database. Survival and recurrence of patients with a cCR who underwent active surveillance were compared with those of patients who underwent planned surgery. Survival was calculated according to the Kaplan-Meier method and compared between groups using the log rank test. The 37 patients who underwent active surveillance were older and tumours were more often located in the middle/upper-third of the oesophagus than in the surgery group of 57 patients. Median follow-up was 28.1 (i.q.r. 17.2-47.1) months for the active surveillance group and 20 (12.9-39.1) months for the surgery group. Overall survival was comparable between the two groups, with 3-year survival rates of 50 (95% c.i. 31 to 67) and 59 (40 to 73)% for the active surveillance and surgery groups respectively (P = 0.55). Three-year progression-free survival for patients who underwent active surveillance was better than in the surgery group: 70 (43 to 85) versus 58 (40 to 72)% (P = 0.02). Overall and progression-free survival was comparable between patients in the active surveillance group and 23 patients in the surgery group who had a pCR (ypT0 N0). The overall recurrence rate was comparable between the groups: 7 of 37 (19.4%) in active surveillance group versus 16 of 49 (32.6%) in surgery group (P = 0.26). Locoregional recurrence was noted more often in the active surveillance group and systemic recurrence in the surgery group. Active surveillance is feasible and safe for patients with oesophageal SCC who have a cCR after chemoradiotherapy.

An online rectal cancer tumoroid biorepository: A resource to facilitate multimodal data integration.

159 Background: Advancing genetic and computational technologies have increased the complexity and quantity of data available in the field of rectal cancer research. As such, there is a need for a centralized source of data to aid and organize current research efforts. To this end, our team has created a unique online biorepository of rectal cancer tumoroids which may serve as a resource for a community of researchers. Methods: The rectal cancer tumoroid biorepository was created in cBioPortal in 2015. Organoids were derived from patient tumor samples (tumoroids). These samples represented multiple treatment timepoints and included primary, recurrent, and metastatic tumors. These tumoroids were further analyzed by various assays such as MSK-IMPACT and IC50 (to fluorouracil, FOLFOX, and FOLFIRI) to obtain patient-specific genomic and chemosensitivity data. A tumoroid profile was then created in cBioPortal for each sample. Clinical information was collected by chart review and annotated into the tumoroid profiles using the unique features of cBioPortal. These included interactive filters and graphical depictions of patient demographics, clinical and pathologic staging, treatment course, clinical response, overall survival, and disease-free survival. Results were organized in an intuitive visual display for convenient analysis. Novel features such as chemosensitivity plots and an interactive patient timeline were incorporated as well. Results: In total, 401 rectal cancer tumoroids have been derived from 177 unique patients. Approximately 32% of the tumoroids were from patients 50 years or younger, and 63% of patients have a treatment naïve sample in our repository. Ten percent of tumoroids were derived from T1-T2 tumors, 56% from T3 tumors, and 17% from T4 tumors. Additionally, 14% of tumoroids were derived from primary tumor recurrences while 6% were derived from metastases. Of the 78% of tumoroids with completely annotated clinical data, 8% were MSI-H, 11% were clinical complete responders, and 5.5% were pathologic complete responders. Lastly, complete IC50 data with clinical correlates has been established for 20% of tumoroids. These data show that tumoroids with a high sensitivity to chemotherapy (FOLFOX) correlated with a 3.3-fold increase in clinical complete response rates in the corresponding patients (p=0.0263). Conclusions: Integrating histopathological, clinicogenomic, and tumoroid response data, this expanding online resource provides a platform to identify valid biomarkers for patient treatment response. This publicly available biorepository built within cBioPortal is intuitive and flexible to accommodate and organize a wide range of data and has the potential to serve as an important resource in rectal cancer research.

Endoscopic Predictors of Residual Tumor After Total Neoadjuvant Therapy: A Post Hoc Analysis From the Organ Preservation in Rectal Adenocarcinoma Trial.

Restaging endoscopy plays a critical role in selecting patients with locally advanced rectal cancer who respond to neoadjuvant therapy for nonoperative management. This study evaluated the restaging endoscopic features that best predict the presence of residual tumor in the bowel wall. This was a post hoc analysis of a prospective randomized trial. The Organ Preservation in Rectal Adenocarcinoma Trial randomly assigned patients across 18 institutions with stage II/III rectal adenocarcinoma to receive either induction or consolidation total neoadjuvant therapy. Surgeons completed a restaging tumor assessment form, which stratified patients across 3 tiers of clinical response. Patients enrolled in the Organ Preservation in Rectal Adenocarcinoma Trial with a completed tumor assessment form were included. The main outcome was residual tumor, which was defined as either an incomplete clinical response or local tumor regrowth within 2 years of restaging. Independent predictors of residual tumor were identified using backward-selected multivariable logistic regression analysis. Subgroup analyses for complete and near complete clinical responders were performed. Surgeons completed restaging forms for 263 patients at a median of 7.7 weeks after neoadjuvant therapy; 128 patients (48.7%) had a residual tumor. On multivariable regression analysis, several characteristics of a near complete response, including ulcer (OR 6.66; 95% CI, 2.54-19.9), irregular mucosa (OR 3.66; 95% CI, 1.61-8.68), and nodularity (OR 2.96; 95% CI, 1.36-6.58), remained independent predictors of residual tumor. A flat scar was associated with lower odds of harboring residual disease (OR 0.32; 95% CI, 0.11-0.93) for patients categorized as clinical complete responders. Limitations include analysis of endoscopic features at a single time point and ambiguities in tumor assessment form response criteria. Patients with ulcer, nodularity, or irregular mucosa, on restaging endoscopy have higher odds of residual tumor. Recognizing negative prognostic implications of these features will help surgeons better select candidates for nonoperative management and suggests that patients with high-risk characteristics would benefit from close interval surveillance. See Video Abstract . ANTECEDENTES:La reestadificación por endoscopia juega un papel crítico en la selección de pacientes con cáncer de recto localmente avanzado que responden a la terapia neoadyuvante para el manejo no quirúrgico.OBJETIVO:Este estudio evaluó las características endoscópicas de reestadificación que mejor predicen la presencia de tumor residual en la pared intestinal.DISEÑO:Este fue un análisis post hoc de un ensayo prospectivo aleatorizado.ESCENARIO:El ensayo Organ Preservation in Rectal Adenocarcinoma aleatorizó a pacientes de 18 instituciones con adenocarcinoma de recto en estadio II/III para recibir terapia neoadyuvante total de inducción o consolidación. Los cirujanos completaron un formulario de reestadificación de evaluación del tumor, que estratificó a los pacientes en tres niveles de respuesta clínica.PACIENTES:Se incluyeron pacientes inscritos en el ensayo de preservación de órganos en adenocarcinoma rectal con un formulario de evaluación del tumor completado.PRINCIPALES MEDIDAS DE RESULTADO:El resultado principal fue presencia de tumor residual, que se definió como una respuesta clínica incompleta o un nuevo crecimiento local del tumor dentro de los dos años posteriores a la reestadificación. Los predictores independientes de tumor residual se identificaron mediante un análisis de regresión logística multivariable seleccionado hacia atrás. Se realizaron análisis de subgrupos para pacientes con respuesta clínica completa y casi completa.RESULTADOS:Los cirujanos completaron formularios de reestadificación para 263 pacientes en una mediana de 7.7 semanas después de la terapia neoadyuvante; 128 (48.7%) tenían tumor residual. En el análisis de regresión multivariable, varias características de una respuesta casi completa, incluyendo úlcera (OR 6.66; IC 95% 2.54-19.9), mucosa irregular (OR 3.66; IC 95% 1.61-8.68) y nodularidad (OR 2.96; IC 95% 1.36 -6.58) siguieron siendo predictores independientes de tumor residual. Una cicatriz plana se asoció con menores probabilidades de albergar enfermedad residual (OR 0.32; IC del 95 %: 0.11-0.93) para los pacientes clasificados como respondedores clínicos completos.LIMITACIONES:Las limitaciones de este estudio incluyen el análisis de las características endoscópicas en un solo momento y las ambigüedades en los criterios de respuesta.en la forma de evaluación del tumorCONCLUSIONES:Los pacientes con úlcera, nodularidad o mucosa irregular en la endoscopia de reestadificación tienen mayores probabilidades de tumor residual. El reconocer las implicaciones pronósticas negativas de estas características ayudará a los cirujanos a seleccionar mejor a los candidatos para el tratamiento no quirúrgico y sugiere que los pacientes con características de alto riesgo se beneficiarían de una vigilancia a intervalos estrechos. (Traducción-Dr. Jorge Silva Velazco ).

291. TREATMENT OUTCOMES ACCORDING TO PATHOLOGICAL RESPONSE AFTER NEOADJUVANT CHEMORADIATION AND SURGEY IN OESOPHAGEAL CANCER

Abstract Background Neoadjuvant chemoradiation followed by surgery is now standard of care for resectable oesophageal cancer. The aim of this study was to analyse various parameters of treatment outcome with respect to pathologic complete responders (pCR) and pathological partial responders. Methods Consecutive 136 patients with operable oesophageal cancer, who received neoadjuvant chemoradiation followed by oesophageal surgery between march 2013 to january 2023 were included. Data was extracted from electronically and physically maintained patient clinical records. Data was collected in mircosoft excel and analysed using Epi Info Version 7.2. Chi square test and student t test were used to test the difference between proportions and means respectively. All tests were 2 tailed and significance level was 0.05. Various demographic, clinical and treatment outcome parameters were analysed according to pathological complete responders (pCR) and pathological partial responders. Results Out of 136 patients, 112(82.3%) had squamous histology. Among 136 patients, 75(55%)had pCR. Postoperative complications were seen in 30(49.18%) of pCR group as compared to 24(32%) in partial responders (p = 0.04). Pulmonary 16(53%) vs 8(33%), cardiac 5(16%) vs 3(12%) and vocal cord palsy 6(20%) vs 8(32%) complications were seen in pCR vs partial responders respectively. 9(14.75%) of pCR group had recurrences as compared to 32(45.33%) in partial responders (p = 0.003). pCR group had distant recurrences in neck 4(66.6%) (p = 0.01) and liver 4(66%) as compared to 2(14.3%) and 4(28.5%) respectively in partial responders. Conclusion High pCR is seen due to more number of patients with squamous histology. pCR has more postoperative pulmonary and cardiac complications which may indicate inherent radiosensitivity and tissue fragility which mandates strict ERAS program and affirms deferred surgery and wait and watch policy for complete clinical responders. Recurrences in pCR are less but are seen mostly in distant sites indicating aggressive surveillance protocol.

Complete response rates in rectal cancer: Temporal changes over a decade in a population-based nationwide cohort

IntroductionIn the past decade many changes in neoadjuvant treatment for patients with rectal cancer have taken place and are expected to impact complete response rates. The aim of this study was to investigate the impact on pathological, and overall, complete response rates in a nationwide population-based cohort, in relation to changes in neoadjuvant treatment and the start of a Watch & Wait (WoW) study. Materials and methodsA nationwide register study using prospectively collected data from the Swedish Colorectal Cancer Register between 2009 and 2020. Patients with rectal cancer stage I-III with a ypT0N0 in the resected specimen after neoadjuvant treatment and clinical complete responders from the yearly inclusion data of the national WoW study were included. Temporal changes in pathological and overall complete response rates were analysed, and differences in neoadjuvant treatment regimens over time and per region were studied. ResultsBetween 2009 and 2020 the pathological complete response rate for rectal cancer remained similar (Mann-Kendall tau of 0.091, p = 0.68) while the overall complete response rate increased significantly from 3.0% to 9.6% (Mann-Kendall tau of 0.818, p < 0.001). The pathological complete response rate for patients receiving short course radiotherapy followed by chemotherapy was reduced by 50% after the introduction of the WoW study. ConclusionsDuring the studied time period the overall complete response rate increased significantly presumably due to changes in national neoadjuvant treatment regimens. Since the start of the national WoW study clinical complete response seem to partly replace pathological complete response.

A watch-and-wait strategy or local excision in complete clinical responders after radiation for early-stage rectal cancer

In The Lancet Healthy Longevity, Alexandra Gilbert and colleagues1 reported quality-of-life and functional outcomes among older patients with early-stage rectal cancer after short-course radiotherapy (SCRT), followed by transanal endoscopic microsurgery, based on the TREC initiative. Among 88 patients included in the analysis, 61 (69%) individuals were allocated to organ preservation through the non-randomised registry on the basis of older age, frailty, or comorbidities. To capture treatment outcomes in this particular cohort of patients who were unfit for radical surgery, data on patient-reported acute and late toxicity, anorectal function, and quality of life at baseline and during 36 months of follow-up were compared with age-matched controls without a cancer diagnosis from the UK general population, and also with the randomised TREC cohort that comprised younger patients with early-stage rectal cancer.

Development of a Reactive Stroma Gene Signature (RSGS) Score to Characterize the Longitudinal Cellular and Molecular Alterations in the Tissue Microenvironment of Locally Advanced Cervical Cancer in Response to Radiotherapy at Single-Cell Resolution

<h3>Purpose/Objective(s)</h3> Understanding how the tumor-associated tissue microenvironment impacts and reflects the response and effectiveness of chemoradiotherapy in cervical and vaginal cancer will open avenues for future clinical interventions and appropriate selection of radiation dose delivered via brachytherapy. <h3>Materials/Methods</h3> Biopsies of tumor and adjacent normal tissue from 7 cervical and vaginal cancer patients were collected longitudinally at baseline and after 45 Gy of ionizing radiation (IR) and analyzed by single-cell RNA sequencing to better understand the tumor, immune, and stromal determinants of response and resistance. Five of the 7 patients had biopsies available at 3 months and were included in this analysis. The single-cell transcriptomes of 4 cervical cancer patients (adenocarcinomas N=3, squamous cell carcinoma N=1) and one patient diagnosed with vaginal cancer (squamous cell carcinoma) were characterized. <h3>Results</h3> Of 5 patients evaluated at 3 months following high-dose-rate brachytherapy, 3 had a complete response, one had persistent disease and one had distant relapse in the peritoneum. Collectively, over 70,000 cells were analyzed in this study. We compared the single-cell transcriptomes of 2 poor responders versus 3 patients with a complete clinical response. The tumor tissue of poor responders had a molecular and cellular signature indicative of a reactive stroma (VCAM1+ fibroblasts, CXCR4+ endothelial cells, and elevated expression of select collagens), with infiltration of immunosuppressive lymphoid and myeloid cells. We developed a reactive stroma gene signature (RSGS) score, which was enriched in cells from irradiated tumor biopsies collected from subjects with poor outcomes. In contrast, the RSGS score was consistently low in normal biopsies at both baseline and post-IR across all subjects, with one exception. The subject with distant relapse showed RSGS score enrichment in the normal post-IR biopsy. When evaluating the cell proportions of immune cell populations, we observed that the abundance of mast cells was consistently lower (< 0.05%) in normal biopsies at both baseline and post-IR. Likewise, the proportion of mast cells in post-IR biopsies was also low in subjects with complete responses. However, in subjects with poor outcomes, the mast cell abundance increased at least three-fold compared to matched baseline tumor biopsies. <h3>Conclusion</h3> Importantly, the findings stemming from this study suggest that treatment-refractory disease upregulated tumor-promoting stromal and immune responses after initiating radiotherapy that was not observed in the tumor microenvironments of complete clinical responders; thus nominating molecular factors that can potentially be therapeutically exploited to improve the efficacy of radiation-based therapies in patients diagnosed with cervical and vaginal cancer. Future studies with larger cohorts enabled by more scalable in situ approaches will be necessary to assess the generalizability of these findings.

High-Risk Features of Esophageal Adenocarcinoma Following Neoadjuvant Chemoradiation: Patients for Whom Surgery Should Not Be Delayed.

Clinical predictors of pathological complete response have not reliably identified patients for whom an organ-sparing approach following neoadjuvant chemoradiation be undertaken for esophageal cancer patients. We sought to identify high-risk predictors of residual carcinoma that may preclude patients from a selective surgical approach. Patients treated with neoadjuvant chemoradiation followed by esophagectomy for esophageal adenocarcinoma were identified. Correlation between clinical and pathologic complete responses were examined. Regression models and recursive partitioning were utilized to identify features associated with residual carcinoma. External validation of these high-risk factors was performed on a data set from an independent institution. A total of 326 patients were identified, in whom clinical complete response was noted in 104/326 (32%). Pathologic complete response was noted in only 33/104 (32%) of these clinical complete responders. Multivariable analysis identified that the presence of stricture ( P =0.011), positive biopsy ( P =0.010), and signet ring cell histology ( P =0.019) were associated with residual cancer. Recursive partitioning corroborated a 94% probability of residual disease, or greater, for each of these features. The positive predictive value was >90% for these characteristics. A SUV max >5.4 at the esophageal primary in the absence of esophagitis was also a high-risk factor for residual carcinoma. External validation confirmed these high-risk factors to be implicated in the finding of residual carcinoma. Clinical parameters of response are poor predictors of complete pathologic response leading to challenges in selecting candidates for active surveillance. However, we characterize several high-risk features for residual carcinoma which indicate that esophagectomy should not be delayed.

Disease Management of Clinical Complete Responders to Neoadjuvant Chemotherapy of Muscle-Invasive Bladder Cancer: A Review of Literature.

Muscle-invasive bladder cancer (MIBC) is an aggressive disease requiring active management. Neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC) is considered the standard treatment paradigm for MIBC patients, which could result in significant perioperative mortality and morbidity, as well as the significant alteration of the quality of life (QOL). Notably, multimodal bladder-preserving treatment strategies have been recommended for highly selected patients. Pathologic complete response (pCR) after NAC is a powerful prognostic indicator of survival for patients with MIBC. Clinical complete response (cCR) is then introduced as a complementary endpoint for pCR to assess disease status preoperatively. Bladder preservation strategy for patients who achieve cCR following NAC is emerging as a new treatment concept. However, the efficiency of the conservative strategy remains controversial. In this state-of-the-art review, we discuss the advantages and limitations of cCR and the feasibility and safety of bladder preservation strategy in highly selected MIBC patients who achieve cCR following NAC. We conclude that a conservative strategy can be considered a reasonable alternative to RC in carefully selected cCR MIBC patients, leading to acceptable oncological outcomes.

A longitudinal cohort study of watch and wait in complete clinical responders after chemo-radiotherapy for localised rectal cancer: study protocol

BackgroundRectal Cancer is a common malignancy. The current treatment approach for patients with locally advanced rectal cancer involves neoadjuvant chemoradiotherapy followed by surgical resection of the rectum. The resection can lead to complications and long-term consequences.A clinical complete response is observed in some patients after chemoradiotherapy. A number of recent studies have shown that patients can be observed safely after completing chemoradiotherapy (without surgery), provided clinical complete response has been achieved. In this approach, resection is reserved for cases of regrowth. This is called the watch and wait approach. This approach potentially avoids unnecessary surgical resection of the rectum and the resulting complications. In this study, we will prospectively investigate this approach.MethodsAdult patients with a diagnosis of rectal cancer planned to receive neoadjuvant long course chemoradiotherapy (± subsequent combination chemotherapy) will be consented into the study prior to commencing treatment. After completing the chemoradiotherapy (± subsequent combination chemotherapy), based on the clinical response, subjects will be allocated to one of the following arms: subjects who achieved a clinical complete response will be allocated to the watch and wait arm and others to the standard management arm (which includes resection). The aim of the study is to determine the rate of local failure and other safety and efficacy outcomes in the watch and wait arm. Patient reported outcome measures and the use of biomarkers as part of the clinical monitoring will be studied in both arms of the study.DiscussionThis study will prospectively investigate the safety of the watch and wait approach. We will investigate predictive biomarkers (molecular biomarkers and imaging biomarkers) and patient reported outcome measures in the study population and the cost effectiveness of the watch and wait approach. This study will also help evaluate a defined monitoring schedule for patients managed with the watch and wait approach. This protocol covers the first two years of follow up, we are planning a subsequent study which covers year 3–5 follow up for the study population.Trial registration.Name of the registry: Australia and New Zealand Clinical Trials Registry (ANZCTR). Trial registration number: Trial ID: ACTRN12619000207112 Registered 13 February 2019,https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=376810

Beneficiaries of radical surgery among clinical complete responders to neoadjuvant chemoradiotherapy in rectal cancer.

This study aimed to identify patients who benefit from radical surgery among those with rectal cancer who achieved clinical complete response (cCR). Patients with locally advanced rectal cancer (LARC; stage II/III) who achieved cCR after neoadjuvant chemoradiotherapy (nCRT) were included (n = 212). Univariate/multivariate Cox analysis was performed to validate predictors for distant metastasis‐free survival (DMFS). A decision tree was generated using recursive partitioning analysis (RPA) to categorize patients into different risk stratifications. Total mesorectal excision (TME) was compared with the watch‐and‐wait (W&W) strategy in each risk group. Two molecular predicators of CEA and CA19‐9 were selected to establish the RPA‐based risk stratification, categorizing LARC patients into low‐risk (n = 139; CA19‐9 < 35 U/mL and CEA < 5 ng/mL) and high‐risk (n = 73; CA19‐9 ≥ 35 U/mL or CEA ≥5 ng/mL) groups. Superior 5‐y DMFS was observed in the low‐risk group vs. the high‐risk group (92.9% vs. 76.2%, P = .002). Low‐risk LARC patients who underwent TME had significantly improved 5‐y DMFS compared with their counterparts receiving the W&W strategy (95.9% vs. 84.3%; P = .028). No significant survival difference was observed in high‐risk patients receiving the 2 treatment modalities (77.9% vs. 94.1%; P = .143). LARC patients with cCR who had both baseline CA19‐9 < 35 U/mL and CEA < 5 ng/mL may benefit from radical surgery.

Early and late morbidity of local excision after chemoradiotherapy for rectal cancer.

BackgroundLocal excision (LE) after chemoradiotherapy is a new option in low rectal cancer, but morbidity has never been compared prospectively with total mesorectal excision (TME). Early and late morbidity were compared in patients treated either by LE or TME after neoadjuvant chemoradiotherapy for rectal cancer.MethodThis was a post-hoc analysis from a randomized trial. Patients with clinical T2/T3 low rectal cancer with good response to the chemoradiotherapy and having either LE, LE with eventual completion TME, or TME were considered. Early (1 month) and late (2 years) morbidities were compared between the three groups.ResultsThere were no deaths following surgery in any of the three groups. Early surgical morbidity (20 per cent LE versus 36 per cent TME versus 43 per cent completion TME, P = 0.025) and late surgical morbidity (4 per cent versus 33 per cent versus 57 per cent, P < 0.001) were significantly lower in the LE group than in the TME or the completion TME group. of LE, was associated with the lowest rate of early (10 versus 18 versus 21 per cent, P = 0.217) and late medical morbidities (0 versus 7 versus 7 per cent, P = 0.154), although this did not represent a significant difference between the groups. The severity of overall morbidity was significantly lower at 2 years after LE compared with TME or completion TME (4 versus 28 versus 43 per cent grade 3–5, P < 0.001).ConclusionThe rate of surgical complications after neoadjuvant chemoradiotherapy in the LE group was half that of TME group at 1 month and 10 times lower at 2 years. LE is a safe approach for organ preservation and should be considered as an alternative to watch-and-wait in complete clinical responders and to TME in subcomplete responders.

Early conformational changes at tumour bed and long term response after neoadjuvant therapy in locally-advanced rectal cancer

ObjectivesTo evaluate how changes in tumour scar depth angle and thickness in the post-neoadjuvant period relate to long-term response in locally-advanced rectal cancer patients. MethodsInformed consent was obtained from all patients and institutional review board approved this retrospective study. Sixty-nine consecutive locally-advanced rectal cancer patients who underwent neoadjuvant therapy and were selected for “Watch-and-Wait” were enrolled. Two radiologists, O1 and O2, blindly and independently reviewed the 1st and 2nd post-neoadjuvant therapy pelvic MRI T2-weighted images and recorded depth angle and thickness of the tumour scar. Value changes were calculated by simple subtraction (2nd-1st). Mann-Whitney U test was employed to assess for significant differences between sustained clinical complete responders (SCR), defined as patients with pathologic complete response or clinical complete response with a minimum follow-up of 1 year; and non-sustained complete responders (non-SCR). Interobserver agreement was estimated using intraclass correlation coefficient (ICC). Data on mrTRG, DWI and endoscopy at 1st and 2nd timepoints were retrieved for comparison. ResultsIn SCR, depth angle change between 1st (med = 10 weeks after end of radiotherapy) and 2nd (med = 23 weeks after end of radiotherapy) timepoints was significantly different (O1:p = 0.004; O2:p = 0.010): the SCR group showed a depth angle reduction (O1:med=-4.45; O2:med=-2.35), whereas non-SCRs showed a depth angle increase (O1:med=+2.60; O2:med=+7.40). Also, at 2nd timepoint, SCR scars were significantly thinner both for O1 (p = 0.003; SCR:med = 7.05 mm; non-SCR:med = 9.4 mm) and O2 (p = 0.006; SCR:med = 6.45 mm; non-SCR:med = 8.2 mm). A depth angle increase >21º between 1st and 2nd timepoints and a scar thickness >10 mm at 2nd timepoint were not sensitive but were highly specific for a non-SCR (91/94 %) for both observers. Interobserver agreement was good for scar depth angle change (ICC = 0.65) and excellent for scar thickness at 2nd timepoint (ICC = 0.84). Of the retrieved data, only DWI at 2nd timepoint was discriminative (p = 0.043) providing a similar sensitivity (33 %) and a slightly lower specificity (87.5 %). ConclusionTumour scar expansion >21° between 1st and 2nd post-neoadjuvancy MRI and a scar thickness >10 mm at 2nd post-neoadjuvancy MRI may consistently indicate a non-SCR with high specificity in locally-advanced rectal cancer patients.

Delayed Surgery after Neoadjuvant Treatment for Rectal Cancer Does Not Lead to Impaired Quality of Life, Worry for Cancer, or Regret.

Simple SummaryRectal cancer patients with an initial (near) complete clinical response to neoadjuvant chemoradiotherapy can be repeatedly assessed to see if a complete response endures. Up to 75% of these patients are able to avoid surgery and its related complications. However, the remaining 25% who ‘fail’ will eventually have to undergo surgery. Although recent studies have shown that patients undergoing delayed surgery have promising surgical and oncological outcomes, it is not known how these patients fare in terms of quality of life. The aim of this study was to compare quality of life between these immediate and delayed surgery groups through validated questionnaires. Our study including 51 patients shows no difference in quality of life, worry for cancer, or decision regret. Therefore, from a quality of life perspective, this study supports a repeated response assessment strategy after chemoradiotherapy for rectal carcinoma to identify all complete responders.Non operative management of complete clinical responders after neoadjuvant treatment for rectal cancer enjoys an increasing popularity because of the increased functional outcome results. Even a near complete response can evolve in a cCR, and therefore further delaying response assessment is accepted. However, up to 40% of patients will develop a regrowth and will eventually require delayed surgery. It is presently unknown if and to what extent quality of life of these patients is affected, compared to patients who undergo immediate surgery. Between January 2015-May 2020, 200 patients were treated with neoadjuvant therapy of whom 94 received TME surgery. Fifty-one (59%) of 87 alive patients returned the questionnaires: 33 patients who underwent immediate and 18 patients who underwent delayed surgery. Quality of life was measured through the QLQ-C30, QLQ-CR29, and Cancer Worry Scale questionnaires. Regret to participate in repeated response assessment protocol was assessed through the Decision Regret Scale. Exploratory factor analysis (EFA) and a ‘known groups comparison’ was performed to assess QLQ questionnaires validity in this sample. Higher mean physical function scores (89.2 vs. 77.6, p = 0.03) were observed in the immediate surgery group, which lost significance after correction for operation type (p = 0.25). Arousal for men was higher in the delayed surgery group (20.0 vs. 57.1, p = 0.02). There were no differences between surgical groups for the other questionnaire items. Worry for cancer was lower in the delayed surgery group (10.8 vs. 14.0, p = 0.21). Regret was very low (12–16%). EFA reproduced most QLQ C-30 and CR29 subscales with good internal consistency. Quality of life is not impaired in patients undergoing delayed TME surgery after neoadjuvant treatment for rectal cancer. Moreover, there is very low regret and no increase in worry for cancer. Therefore, from a quality of life perspective, this study supports a repeated response assessment strategy after CRTx for rectal carcinoma to identify all complete responders.

Conditional recurrence-free survival of clinical complete responders managed by watch and wait after neoadjuvant chemoradiotherapy for rectal cancer in the International Watch &amp; Wait Database: a retrospective, international, multicentre registry study

Watch and wait is a novel management strategy in patients with rectal cancer who have a clinical complete response after neoadjuvant chemoradiotherapy. Surveillance of these patients is generally intensive, because local regrowth (with the potential for salvage) occurs in 25% of patients, and distant metastases occur in 10% of patients. It is unclear for how long these patients should be followed up. To address this issue, we did conditional survival modelling using the International Watch & Wait Database (IWWD), which is a large-scale registry of patients with a clinical complete response after neoadjuvant chemotherapy who have been managed by a watch-and-wait strategy. We did a retrospective, multicentre registry study using a dataset from the IWWD, which includes data from 47 clinics across 15 countries. We selected patients (aged ≥18 years) with rectal cancer who had a clinical complete response after neoadjuvant chemotherapy, and who were subsequently managed by a watch-and-wait strategy between Nov 25, 1991, and Dec 31, 2015. Patients who had not achieved a clinical complete response or who had undergone any surgical procedure were excluded. The criteria used for defining a clinical complete response and the specific surveillance strategies were at the discretion of each participating centre. We used conditional survival modelling to estimate the probability of patients remaining free of local regrowth or distant metastasis for an additional 2 years after sustaining a clinical complete response or being distant metastasis-free for 1, 3, and 5 years from the date of the decision to commence watch and wait. The primary outcomes were conditional local regrowth-free survival at 3 years, and conditional distant metastasis-free survival at 5 years. We identified 793 patients in the IWWD with clinical complete response who had been managed by a watch-and-wait strategy. Median follow-up was 55·2 months (IQR 36·0-75·6). The probability of remaining free from local regrowth for an additional 2 years if a patient had a sustained clinical complete response for 1 year was 88·1% (95% CI 85·8-90·9), for 3 years was 97·3% (95·2-98·6), and for 5 years was 98·6% (97·6-100·0). The probably of remaining free from distant metastasis for a further 2 years in patients who had a clinical complete response without distant metastasis for 1 year was 93·8% (92·3-95·9), for 3 years was 97·8% (96·6-99·3), and for 5 years was 96·6% (94·0-98·9). These results suggest that the intensity of active surveillance in patients with rectal cancer managed by a watch-and-wait approach could be reduced if they achieve and maintain a clinical complete response within the first 3 years of starting this approach. European Registration of Cancer Care, financed by the European Society of Surgical Oncology, the Champalimaud Foundation Lisbon, the Bas Mulder Award, granted by the Alpe d'HuZes Foundation and the Dutch Cancer Society, the European Research Council Advanced Grant, and the National Institute of Health and Research Manchester Biomedical Research Centre.

Analysis of long-term oncological results of clinical versus pathological responses after neoadjuvant treatment in locally advanced rectal cancer

BackgroundNonoperative management after neoadjuvant treatment in low rectal cancer enables organ preservation and avoids surgical morbidity. Our aim is to compare oncological outcomes in patients with clinical complete response in watch and wait strategy with those who received neoadjuvant therapy followed by surgery with a pathological complete response.MethodsPatients with non-metastatic rectal cancer after neoadjuvant treatment with clinical complete response in watch and wait approach (group 1, n = 26) and complete pathological responders (ypT0N0) after chemoradiotherapy and surgery (group 2, n = 22), between January 2011 and October 2018, were included retrospectively, and all of them evaluated and followed in a multidisciplinary team. A comparative analysis of local and distant recurrence rates and disease-free and overall survival between both groups was carried out. Statistical analysis was performed using log-rank test, Cox proportional hazards regression model, and Kaplan-Meier curves.ResultsNo differences were found between patient’s demographic characteristics in both groups. Group 1: distance from the anal verge mean 5 cm (r = 1–12), 10 (38%) stage III, and 7 (27%) circumferential resection margin involved. The median follow-up of 47 months (r = 6, a 108). Group 2: distance from the anal verge mean 7 cm (r = 2–12), 16 (72%) stage III, and 13 (59%) circumferential resection margin involved. The median follow-up 49.5 months (r = 3, a 112). Local recurrence: 2 patients in group 1 (8.3%) and 1 in group 2 (4.8%) (p = 0.6235). Distant recurrence: 1 patient in group 1 (3.8%) and 3 in group 2 (19.2%) (p = 0.2237). Disease-free survival: 87.9% in group 1, 80% in group 2 (p = 0.7546). Overall survival: 86% in group 1 and 85% in group 2 (p = 0.5367).ConclusionOncological results in operated patients with pathological complete response were similar to those in patients under a watch and wait strategy mediating a systematic and personalized evaluation. Surgery can safely be deferred in clinical complete responders.

Modern MR Imaging Technology in Rectal Cancer; There Is More Than Meets the Eye.

MR imaging (MRI) is now part of the standard work up of patients with rectal cancer. Restaging MRI has been traditionally used to plan the surgical approach. Its role has recently increased and been adopted as a valuable tool to assist the clinical selection of clinical (near) complete responders for organ preserving treatment. Recently several studies have addressed new imaging biomarkers that combined with morphological provides a comprehensive picture of the tumor. Diffusion-weighted MRI (DWI) has entered the clinics and proven useful for response assessment after chemoradiotherapy. Other functional (quantitative) MRI technologies are on the horizon including artificial intelligence modeling. This narrative review provides an overview of recent advances in rectal cancer (re)staging by imaging with a specific focus on response prediction and evaluation of neoadjuvant treatment response. Furthermore, directions are given for future research.

Watch and Wait Is Cost-Effective for Complete Clinical Responders after Neoadjuvant Treatment for Locally Advanced Rectal Cancer

Cui, Christina L. BS; Luo, William Y. BS; Ramamoorthy, Sonia MD, FACS, FASCRS; Simpson, Daniel R. MD, MAS; Murphy, James MD, MS; Lopez, Nicole MD Author Information

ΔKi67 proliferation index as independent predictive and prognostic factor of outcome in luminal breast cancer: data from neoadjuvant letrozole-based treatment.

A key tool for monitoring breast cancer patients under neoadjuvant treatment is the identification of reliable predictive markers. Ki67 has been identified as a prognostic and predictive marker in ER-positive breast cancer. Ninety ER-positive, HER2 negative locally advanced breast cancer patients received letrozole (2.5 mg daily) and cyclophosphamide (50 mg daily) with/without Sorafenib (400 mg/bid daily) for 6 months before undergoing surgery. Ki67 expression and tumor size measured with caliber were determined at baseline, after 30 days of treatment and at the end of treatment. Patients were assigned to a clinical response category according to Response Evaluation Criteria in Solid Tumors, both at 30 days and before surgery and further classified as high-responder and low-responder according to the median variation of Ki67 values between biopsy and 30 days and between biopsy and surgery time. The predictive role of Ki67 and its changes with regard to clinical response and survival was analyzed. No differences in terms of survival outcomes emerged between the arms of treatment, while we observed a higher percentage of women with progression or stable disease in arm with the combination containing Sorafenib (20.5% vs 7.1%, p = 0.06). Clinical complete responders experienced a greater overall variation in Ki67 when compared with partial responders and patients with progressive/stable disease (66.7% vs 30.7%, p = 0.009). High responders showed a better outcome than low responders in terms of both disease-free survival (p = 0.009) and overall survival (p = 0.002). ΔKi67 score evaluated between basal and residual tumor at definitive surgery showed to be highly predictive of clinical complete response, and a potential parameter to be used for predicting disease-free survival and overall survival in luminal breast cancer treated with neoadjuvant endocrine-based therapy.