Advances and challenges in treatment of locally advanced rectal cancer

Omission of or Poor Response to Preoperative Chemoradiotherapy Impacts Radial Margin Positivity Rates in Locally Advanced Rectal Cancer

BACKGROUND

In the setting of multidisciplinary standardized care of locally advanced rectal cancer, preoperative chemoradiotherapy and total mesorectal excision have become the mainstay treatment.

OBJECTIVE

This study aimed to evaluate whether the lack of preoperative chemoradiotherapy or poor response to it is associated with higher radial margin disease involvement in patients with locally advanced rectal cancer.

DESIGN

This is a retrospective cohort study using a publicly available database.

SETTING

Data were collected from the proctectomy-targeted National Surgical Quality Improvement Project file from 2016 to 2017.

PATIENTS

A total of 1161 patients were analyzed. They were categorized into 3 groups: patients who did not receive any preoperative chemoradiotherapy (28.6%), patients who received and responded to preoperative chemoradiotherapy (41.2%), and patients who received but did not respond to preoperative chemoradiotherapy (30.2%).

MAIN OUTCOME MEASURES

Response to treatment was determined by using the American Joint Committee on Cancer pretreatment and final pathological staging. Circumferential radial margin was extracted from the targeted proctectomy file.

RESULTS

Disease-involved positive circumferential radial margin was found in 86 (7.4%) cases. Positive radial margin was noted in 11 of 479 patients (2.3%) who underwent preoperative chemoradiotherapy and responded to treatment, 30 of 350 patients (8.6%) who did not respond or had a poor response to preoperative chemoradiotherapy, and 45 of 332 patients (13.6%) who did not receive preoperative chemoradiotherapy (p < 0.001). Regression analysis demonstrated that patients who do not receive preoperative chemoradiotherapy or have poor response to it have 6.6 and 4 times higher chances of having a positive radial margin.

LIMITATIONS

There is a risk of selection bias, unidentified confounders, and missing data despite the use of a nationwide cohort.

CONCLUSIONS

Omission of indicated preoperative chemoradiotherapy or poor response to it is associated with increased risk of radial margin positivity. More efforts are needed for standardized rectal cancer care with the appropriate use of preoperative chemoradiotherapy. See Video Abstract at http://links.lww.com/DCR/B467.

LA OMISIN O LA ESCASA RESPUESTA A QUIMIORADIOTERAPIA PREOPERATORIA, AFECTA LAS TASAS DE POSITIVIDAD DEL MARGEN RADIAL, EN EL CNCER RECTAL LOCALMENTE AVANZADO

ANTECEDENTES:En el contexto de la atención multidisciplinaria estandarizada del cáncer rectal localmente avanzado, la quimioradioterapia preoperatoria y la escisión mesorrectal total, se han convertido en el tratamiento principal.OBJETIVO:Evaluar si la omisión de quimioradioterapia preoperatoria o la escasa respuesta, se asocia con mayor enfermedad del margen radial, en pacientes con cáncer rectal localmente avanzado.DISEÑO:Estudio de cohorte retrospectivo utilizando una base de datos disponible públicamente.AJUSTE:Se recopilaron datos del archivo del Proyecto Nacional de Mejora de la Calidad Quirúrgica dirigido a la proctectomía de 2016-2017.PACIENTES:Se analizaron un total de 1161 pacientes. Clasificados en tres grupos: pacientes que no recibieron quimioradioterapia preoperatoria (28,6%), pacientes que recibieron y respondieron a quimioradioterapia preoperatoria (41,2%) y pacientes que recibieron pero no respondieron a la quimioradioterapia preoperatoria (30,2%).PRINCIPALES MEDIDAS DE RESULTADO:La respuesta al tratamiento se determinó utilizando el pre tratamiento y la estatificación patológica final, del American Joint Committee on Cancer. El margen radial circunferencial se extrajo del archivo de proctectomía dirigida.RESULTADOS:Se encontró enfermedad que abarcaba el margen radial circunferencial +, en el 86 (7,4%) casos. Se observó el margen radial +, en 11 de 479 pacientes (2,3%) que se sometieron a quimioradioterapia preoperatoria y respondieron al tratamiento, 30 de 350 pacientes (8,6%) que no respondieron o tuvieron una mala respuesta con quimioradioterapia preoperatoria y en 45 de 332 pacientes (13,6%) que no recibieron quimioradioterapia preoperatoria (p <0,001). El análisis de regresión demostró que los pacientes que no reciben quimioradioterapia preoperatoria o que tienen escasa respuesta, presentan respectivamente, 6,6 y 4 veces más probabilidades de tener un margen radial +.LIMITACIONES:Existe el riesgo de sesgo de selección, factores de confusión no identificados y datos faltantes a pesar del uso de una cohorte nacional.CONCLUSIONES:La omisión de la quimioradioterapia preoperatoria indicada o la escasa respuesta, se asocian a un mayor riesgo de positividad del margen radial. Se necesitan mayores esfuerzos en la atención estandarizada del cáncer rectal, con el uso adecuado de quimioradioterapia preoperatoria. Consulte Video Resumen en http://links.lww.com/DCR/B467.

Liposome technologies towards colorectal cancer therapeutics

Colorectal cancer (CRC) is the third most common cancer and the fourth most common deadly cancer worldwide. After treatment with curative intent recurrence rates vary with staging 0-13% in Stage 1, 11-61% in S2 and 28-73% in Stage 3. The toxicity to healthy tissues from chemotherapy and radiotherapy and drug resistance severely affect the quality of life and cancer specific outcomes of CRC patients. To overcome some of these limitations, many efforts have been made to develop nanomaterial-based drug delivery systems. Among these nanocarriers, liposomes represented one of the most successful candidates in delivering targeted oncological treatment, improving safety profile and therapeutic efficacy of encapsulated drugs. In this review we will discuss liposome design with a particular focus on the targeting feature and triggering functions. We will also summarise the recent advances in liposomal delivery system for CRC treatment in both the preclinical and clinical studies. We will finally provide our perspectives on the liposome technology development for the future clinical translation. STATEMENT OF SIGNIFICANCE: Conventional treatments for colorectal cancer (CRC) severely affect the therapeutic effects for advanced patients. With the development of nanomedicines, liposomal delivery system appears to be one of the most promising nanocarriers for CRC treatment. In last three years several reviews in this area have been published focusing on the preclinical research and drug delivery function, which is a fairly narrow focus in the field of liposome technology for CRC therapy. Our review presented the most recent advances of the liposome technology (both clinical and preclinical applications) for CRC with strong potential for further clinical translation. We believe it will attract lots of attention from various audiences, including researchers, clinicians and the industry.

Could the conservative approach be considered safe in the treatment of locally advanced rectal cancer in case of a clinical near-complete or complete response? A retrospective analysis

BACKGROUND

Conservative approach has emerged as an option for the management of rectal cancer (RC) patients with a near or complete clinical response after neoadjuvant chemoradiotherapy (nCRT). The aim of this study is to assess the impact of the conservative approach by comparing patients' survival outcomes and quality of life with those who had surgical resection.

METHODS

A single-institution and retrospective study including RC patients who reached a near complete or complete clinical response after nCRT from January 2010 to September 2019. Conservative approaches included local excision or watch and wait strategy; surgery approaches included anterior resection or abdominal-perineal resection.Local regrowth (LR), overall survival, disease free survival, metastasis free survival and colostomy free survival were evaluated through Kaplan-Meier curves and compared trough log-rank tests. Quality of life was measured by the following validated questionnaires: EORTC QLC30, EORTC QLQ - CR29 and Fecal Incontinence Quality of Life scale.

RESULTS

Overall 157 patients were analyzed: 105 (66,9%) underwent radical surgery and 52 (33,1%) had a conservative approach. With a median follow-up of 51 months, 2 patients in the surgical group had a local recurrence and 8 in the conservative group had a LR, respectively. Distance metastasis occurred in 7 and 1 patients of surgical and conservative group, respectively. No differences were detected in terms of survival outcomes except for colostomy free survival (p: 0,01). The conservative group showed better intestinal (p < 0.01) and sexual (p: 0,04) function and emotional status (p: 0,02).

CONCLUSIONS

Conservative approach seems to be safe in terms of survival outcomes with a significant advantage on quality of life in RC patients who achieved clinical complete response after nCRT.

Development of a Joint Prediction Model Based on Both the Radiomics and Clinical Factors for Predicting the Tumor Response to Neoadjuvant Chemoradiotherapy in Patients with Locally Advanced Rectal Cancer

Purpose

Neoadjuvant chemoradiotherapy (nCRT) has become the standard treatment for locally advanced rectal cancer (LARC). However, the accuracy of traditional clinical indicators in predicting tumor response is poor. Recently, radiomics based on magnetic resonance imaging (MRI) has been regarded as a promising noninvasive assessment method. The present study was conducted to develop a model to predict the pathological response by analyzing the quantitative features of MRI and clinical risk factors, which might predict the therapeutic effects in patients with LARC as accurately as possible before treatment.

Patients and Methods

A total of 82 patients with LARC were enrolled as the training cohort and internal validation cohort. The pre-CRT MRI after pretreatment was acquired to extract texture features, which was finally selected through the minimum redundancy maximum relevance (mRMR) algorithm. A support vector machine (SVM) was used as a classifier to classify different tumor responses. A joint radiomics model combined with clinical risk factors was then developed and evaluated by receiver operating characteristic (ROC) curves. External validation was performed with 107 patients from another center to evaluate the applicability of the model.

Results

Twenty top image texture features were extracted from 6192 extracted-radiomic features. The radiomics model based on high-spatial-resolution T2-weighted imaging (HR-T2WI) and contrast-enhanced T1-weighted imaging (T1+C) demonstrated an area under the curve (AUC) of 0.8910 (0.8114–0.9706) and 0.8938 (0.8084–0.9792), respectively. The AUC value rose to 0.9371 (0.8751–0.9997) and 0.9113 (0.8449–0.9776), respectively, when the circumferential resection margin (CRM) and carbohydrate antigen 19-9 (CA19-9) levels were incorporated. Clinical usefulness was confirmed in an external validation cohort as well (AUC, 0.6413 and 0.6818).

Conclusion

Our study indicated that the joint radiomics prediction model combined with clinical risk factors showed good predictive ability regarding the treatment response of tumors as accurately as possible before treatment.

LMNB2 promotes the progression of colorectal cancer by silencing p21 expression

Colorectal cancer is the second common cause of death worldwide. Lamin B2 (LMNB2) is involved in chromatin remodeling and the rupture and reorganization of nuclear membrane during mitosis, which is necessary for eukaryotic cell proliferation. However, the role of LMNB2 in colorectal cancer (CRC) is poorly understood. This study explored the biological functions of LMNB2 in the progression of colorectal cancer and explored the possible molecular mechanisms. We found that LMNB2 was significantly upregulated in primary colorectal cancer tissues and cell lines, compared with paired non-cancerous tissues and normal colorectal epithelium. The high expression of LMNB2 in colorectal cancer tissues is significantly related to the clinicopathological characteristics of the patients and the shorter overall and disease-free cumulative survival. Functional analysis, including CCK8 cell proliferation test, EdU proliferation test, colony formation analysis, nude mouse xenograft, cell cycle, and apoptosis analysis showed that LMNB2 significantly promotes cell proliferation by promoting cell cycle progression in vivo and in vitro. In addition, gene set enrichment analysis, luciferase report analysis, and CHIP analysis showed that LMNB2 promotes cell proliferation by regulating the p21 promoter, whereas LMNB2 has no effect on cell apoptosis. In summary, these findings not only indicate that LMNB2 promotes the proliferation of colorectal cancer by regulating p21-mediated cell cycle progression, but also suggest the potential value of LMNB2 as a clinical prognostic marker and molecular therapy target.

Optimal Size Criteria for Lateral Lymph Node Dissection After Neoadjuvant Chemoradiotherapy for Rectal Cancer

BACKGROUND

Although chemoradiotherapy followed by radical surgery without lateral lymph node dissection is the current standard treatment in patients with rectal cancer, recent studies have demonstrated the benefits of adding lateral lymph node dissection to total mesorectal excision in patients with suspected lateral lymph node metastasis. However, the optimal indication for lateral lymph node dissection after chemoradiotherapy has not been determined.

OBJECTIVE

This study aimed to establish the optimal indication for lateral lymph node dissection after chemoradiotherapy in patients with rectal cancer.

DESIGN

This is a retrospective study.

SETTINGS

This study was conducted at a single referral hospital.

PATIENTS

A total of 279 patients with rectal cancer who underwent chemoradiotherapy followed by radical surgery between 2007 and 2018 were retrospectively enrolled.

MAIN OUTCOME MEASURES

The largest lateral lymph nodes on CT were retrospectively assessed and compared with the pathologic results of dissected lateral lymph nodes and recurrences in lateral lymph node areas.

RESULTS

The incidence of lateral lymph node metastasis after chemoradiotherapy was estimated to be 9.3%. Although patients with lateral lymph node metastasis frequently developed distant recurrence, 40.4% survived for >5 years without recurrence. An analysis of the lateral lymph node sizes showed that lateral lymph node size ≥8 mm before chemoradiotherapy was the optimal criterion for lateral lymph node dissection, with a sensitivity and specificity of 92.3% and 78.7%. Using this criterion, 72.0% of the patients could be spared lateral lymph node dissection.

LIMITATIONS

Because of the retrospective nature of the present study, the selection of patients who underwent lateral lymph node dissection was biased.

CONCLUSIONS

The optimal indication for lateral lymph node dissection was lateral lymph node size ≥8 mm before chemoradiotherapy. Cancer could be eradicated in >30% of patients with lateral lymph node metastasis by dissecting metastatic lateral lymph nodes. See Video Abstract at http://links.lww.com/DCR/B428.

CRITERIOS DE TAMAO PTIMO PARA LA DISECCIN DE GANGLIOS LINFTICOS LATERALES DESPUS DE LA QUIMIORRADIOTERAPIA NEOADYUVANTE PARA EL CNCER DE RECTO

ANTECEDENTES:Aunque la quimiorradioterapia seguida por cirugía radical sin disección de ganglios linfáticos laterales es el tratamiento estándar actual en pacientes con cáncer de recto, estudios recientes han demostrado beneficios de agregar disección de ganglios linfáticos laterales a la escisión mesorrectal total en pacientes con sospecha de metástasis de ganglios linfáticos laterales. Sin embargo, no se ha determinado la indicación óptima para la disección de los ganglios linfáticos laterales después de la quimiorradioterapia.OBJETIVO:Este estudio tuvo como objetivo establecer la indicación óptima para la disección de los ganglios linfáticos laterales después de la quimiorradioterapia en pacientes con cáncer de recto.DISEÑO:Estudio retrospectivo.ENTORNO CLINICO:Este estudio se realizó en un solo hospital de referencia.PACIENTES:Se inscribieron retrospectivamente un total de 279 pacientes con cáncer de recto que se sometieron a quimiorradioterapia seguida por cirugía radical entre 2007 y 2018.PRINCIPALES MEDIDAS DE VALORACION:Los ganglios linfáticos laterales más grandes en la tomografía computarizada se evaluaron retrospectivamente y se compararon con los resultados patológicos de los ganglios linfáticos laterales disecados y recidivas en las áreas de los ganglios linfáticos laterales.RESULTADOS:Se estimó que la incidencia de metástasis en los ganglios linfáticos laterales después de la quimiorradioterapia fue del 9,3%. Aunque los pacientes con metástasis en los ganglios linfáticos laterales con frecuencia desarrollaron recurrencia a distancia, el 40,4% sobrevivió durante más de 5 años sin recurrencia. Un análisis de los tamaños de los ganglios linfáticos laterales mostró que la mayor dimensión de los ganglios linfáticos laterales ≥ 8 mm antes de la quimiorradioterapia eran el criterio óptimo para la disección de los ganglios linfáticos laterales, con una sensibilidad y especificidad del 92,3% y 78,7%, respectivamente. Utilizando este criterio, el 72,0% de los pacientes podría evitarse la disección de los ganglios linfáticos laterales.LIMITACIONES:Debido a la naturaleza retrospectiva del presente estudio, la selección de pacientes que fueron sometidos a disección de ganglios linfáticos laterales fue sesgada.CONCLUSIÓN:La indicación óptima para la disección de los ganglios linfáticos laterales fue la dimensión mayor de los ganglios linfáticos laterales ≥ 8 mm antes de la quimiorradioterapia. El cáncer se podría erradicar en más del 30% de los pacientes con metástasis en los ganglios linfáticos laterales disecando los ganglios linfáticos laterales metastásicos. Consulte Video Resumen en http://links.lww.com/DCR/B428.

Comparison of percentage changes in quantitative diffusion parameters for assessing pathological complete response to neoadjuvant therapy in locally advanced rectal cancer: a meta-analysis

PURPOSE

To evaluate and compare the diagnostic performance of percentage changes in apparent diffusion coefficient (∆ADC%) and slow diffusion coefficient (∆D%) for assessing pathological complete response (pCR) to neoadjuvant therapy in patients with locally advanced rectal cancer (LARC).

METHODS

A systematic search in PubMed, EMBASE, the Web of Science, and the Cochrane Library was performed to retrieve related original studies. For each parameter (∆ADC% and ∆D%), we pooled the sensitivity, specificity and calculated the area under summary receiver operating characteristic curve (AUROC) values. Meta-regression and subgroup analyses were performed to explore heterogeneity among the studies on ∆ADC%.

RESULTS

15 original studies (804 patients with 805 lesions, 15 studies on ∆ADC%, 4 of the studies both on ∆ADC% and ∆D%) were included. pCR was observed in 213 lesions (26.46%). For the assessment of pCR, the pooled sensitivity, specificity and AUROC of ∆ADC% were 0.83 (95% confidence intervals [CI] 0.76, 0.89), 0.74 (95% CI 0.66, 0.81), 0.87 (95% CI 0.83, 0.89), and ∆D% were 0.70 (95% CI 0.52, 0.84), 0.81 (95% CI 0.65, 0.90), 0.81 (95% CI 0.77, 0.84), respectively. In the four studies on the both metrics, ∆ADC% yielded an equivalent diagnostic performance (AUROC 0.80 [95% CI 0.76, 0.83]) to ∆D%, but lower than in the studies (n = 11) only on ∆ADC% (AUROC 0.88 [95% CI 0.85, 0.91]). Meta-regression and subgroup analyses showed no significant factors affecting heterogeneity.

CONCLUSIONS

Our meta-analysis confirms that ∆ADC% could reliably evaluate pCR in patients with LARC after neoadjuvant therapy. ∆D% may not be superior to ∆ADC%, which deserves further investigation.

NOTCH Activation via gp130/STAT3 Signaling Confers Resistance to Chemoradiotherapy

Simple Summary

Resistance to chemoradiotherapy represents a fundamental problem in modern oncology because it exposes patients to the potential negative side-effects of both radiation and chemotherapy without any clinical benefit. This study uncovers that the inflammatory signaling hub STAT3 conspires with the cell fate regulator NOTCH in rendering tumor cells refractory to chemoradiotherapy. The dichotomic signal alliance is based on a so-far unknown STAT3 target gene, RBPJ, providing the transcriptionally active partner of NOTCH intracellular domain. Unexpectedly, the latter is permanently produced by tonic proteolysis. Tumor mouse models and cancer patient cohorts demonstrate the usefulness of the STAT3/NOTCH axis as biomarker for patient stratification, and importantly, that STAT3 inhibition is a promising treatment option for re-sensitization of CRT-refractory tumors.

Abstract

Resistance of tumor cells to chemoradiotherapy represents a fundamental problem in clinical oncology. The underlying mechanisms are actively debated. Here we show that blocking inflammatory cytokine receptor signaling via STAT3 re-sensitized treatment-refractory cancer cells and abolished tumor growth in a xenograft mouse model when applied together with chemoradiotherapy. STAT3 executed treatment resistance by triggering the expression of RBPJ, the key transcriptional regulator of the NOTCH pathway. The mandatory RBPJ interaction partner, NOTCH intracellular domain, was provided by tumor cell-intrinsic expression of NOTCH ligands that caused tonic NOTCH proteolysis. In fact, NOTCH inhibition phenocopied the effect of blocking STAT3 signaling. Moreover, genetic profiling of rectal cancer patients revealed the importance of the STAT3/NOTCH axis as NOTCH expression correlated with clinical outcome. Our data uncovered an unprecedented signal alliance between inflammation and cellular development that orchestrated resistance to chemoradiotherapy. Clinically, our findings allow for biomarker-driven patient stratification and offer novel treatment options.

Robotic Partial Excision of Levator-Ani Muscle for Locally Advanced Low Rectal Cancer Invading Ipsilateral Pelvic Floor

Tumors at the level of the anorectal junction had required abdominoperineal resection (APR) to achieve an adequate resection margin. However, in the cases of tumor invading ipsilateral levator-ani muscle (LAM), <i>en-bloc</i> resection of the rectum with LAM including tumor would be possible. This video is to show the critical anatomic steps of this procedure. A video was produced from the robotic right partial excision of LAM (PELM) performed in a 57-year-old female patient with rectal cancer at 3 cm from the anal verge, invading the ipsilateral anorectal ring, who had received neoadjuvant chemoradiotherapy. The patient discharged at postoperative day 8 without complication. The pathology of the surgical specimen revealed ypT3N1bM0. The secure resection margin from the tumor was achieved. Robotic PELM is the sphincter-preserving technique that can be an alternative treatment option for low rectal cancer invading the ipsilateral LAM, which has been an indication for APR or extralevator APR.

Robotic Partial Excision of Levator-Ani Muscle for Locally Advanced Low Rectal Cancer Invading Ipsilateral Pelvic Floor

Tumors at the level of the anorectal junction had required abdominoperineal resection (APR) to achieve an adequate resection margin. However, in the cases of tumor invading ipsilateral levator-ani muscle (LAM), en-bloc resection of the rectum with LAM including tumor would be possible. This video is to show the critical anatomic steps of this procedure. A video was produced from the robotic right partial excision of LAM (PELM) performed in a 57-year-old female patient with rectal cancer at 3 cm from the anal verge, invading the ipsilateral anorectal ring, who had received neoadjuvant chemoradiotherapy. The patient discharged at postoperative day 8 without complication. The pathology of the surgical specimen revealed ypT3N1bM0. The secure resection margin from the tumor was achieved. Robotic PELM is the sphincter-preserving technique that can be an alternative treatment option for low rectal cancer invading the ipsilateral LAM, which has been an indication for APR or extralevator APR.

The value of intravoxel incoherent motion and diffusion kurtosis imaging in the assessment of tumor regression grade and T stages after neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer

PURPOSE

To evaluate the role of IVIM and diffusion kurtosis imaging (DKI) in identifying pathologic complete response (pCR) and T stages after neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC).

METHOD

Forty-two patients with biopsy-proven rectal adenocarcinoma, who underwent both pre-and post-CRT MRI with IVIM and DKI sequences on a 3 T scanner, were enrolled prospectively. According to the pathologic ypTNM stages and tumor regression grade (TRG), patients were grouped into pCR (TRG0) and non-pCR (TRG1-3) groups and low T stage (ypT0-2) and high T stage (ypT3-4) groups. IVIM parameters (the slow diffusion coefficient [D], fast diffusion coefficient [D*], perfusion fraction [f]), DKI parameters (mean diffusivity [MD] and mean kurtosis [MK]), and mono-exponential ADC were calculated and analyzed between groups.

RESULTS

The pCR group had significantly higher post-CRT ADC, D*, f, and MD values than non-pCR group, and higher percent changes in the ADC, f, and MD values (all P < 0.05). The post-CRT MD values yielded the highest AUC (0.788) with higher sensitivity than post-ADC values (82.9 % vs. 77.1 %, respectively). Post-CRT ADC and MD values and the percent changes in the ADC and MD values were also negatively correlated with TRG (all P < 0.05). Besides, negative correlations were found among the pre-CRT MD, post-CRT ADC, D, f, and MD values and the ypT stages (all P < 0.05).

CONCLUSIONS

Both IVIM and DKI parameters could provide more information when evaluating pCR and T stages after nCRT. In particular, the diagnostic performance of the MD values was more valuable than ADC values in being able to determine pCR.

Impact of Total Neoadjuvant Therapy vs. Standard Chemoradiotherapy in Locally Advanced Rectal Cancer: A Systematic Review and Meta-Analysis of Randomized Trials

Multimodality treatment is a standard of care for LARC, but the optimal sequencing of the treatment modalities remains unclear. Several randomized clinical trials (RCTs) compared total neoadjuvant treatment (TNT) vs. standard neoadjuvant chemoradiotherapy (CRT) with inconsistent results. A systematic review and meta-analysis was performed to evaluate the efficacy of TNT in terms of complete pathological response (pCR) rate, disease-free and overall survival vs. standard CRT in LARC. A systematic search was performed through MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and meeting abstracts up to May 2020. RCTs comparing CRT vs. TNT followed by surgery in LARC were eligible for the study. Study selection and data extraction were done following PRISMA guidelines by two independent reviewers. The Mantel-Haenzel method was used to obtain a fixed-effects model of pooled odds or hazard ratios for the main outcomes. Eight RCTs, including 2301 patients, met the eligibility criteria. TNT significantly improved pCR rate (OR = 1.99, 95% confidence interval (CI) 1.59-2.49; p < 0.001), 3-year disease-free-survival (DFS) (HR = 0.82, 95%CI 0.71-0.95; p = 0.01) and 3-year overall survival (OS) (hazard ratio (HR) = 0.81, p = 0.04). Grade 3-4 adverse events were not significantly different in both strategies (OR = 1.58; p = 0.14). An improved pCR rate was documented regardless of the type of radiotherapy administered (long vs. short fractionation schedules). No significant heterogeneity was found. The results of this meta-analysis show that TNT improves pCR and survival rates vs. standard preoperative CRT in patients with LARC. TNT may become a new standard of care in LARC, although longer follow-up is needed to properly assess its long-term impact on survival.

Predictive Role of Biopsy Based Biomarkers for Radiotherapy Treatment in Rectal Cancer

Background and Purpose: Radiation therapy has long been contemplated as an important mode in the treatment of rectal cancer. However, there are few ideal tools available for clinicians to make a radiotherapy decision at the time of diagnosis for rectal cancer. The purpose of this study was to assess whether biomarkers expressed in the biopsy could help to choose the suitable therapy and provide predictive and/or prognostic information. Experimental Design: In total, 30 biomarkers were analyzed in 219 biopsy samples before treatment to discover the possibility of using them as an indicator for radiotherapy selection, diagnosis, survival and recurrence. Results: Twenty-two biomarkers (COX2-RT, COX2-NonRT, etc.; 36.67%) had diagnostic value. For survival, four biomarkers (NFKBP65, p130, PINCH and PPAR) were significant in regulating gene promoter activity and overall survival, while four had a trend (AEG1, LOX, SATB1 and SIRT6). Three biomarkers (COX2, PINCH and WRAP53) correlated with disease-free survival, while eight had a trend (AEG1, COX2, Ki67, LOX, NFKBP65, PPAR and SATB1). Four biomarkers (COX2-RT, NFKBP65cyto-RT, P130cyto-NonRT and PPARcyto-RT) were independent prognostic factors for recurrence. NFKBP65 and SIRT6 were significantly correlated with lymph node metastasis regardless of radiation. Patients with high AEG1, LOX, NFKBP65, PPAR and SATB1 had or showed a positive trend for better survival after radiotherapy, while those with positive PINCH and WRAP53 expression would not benefit from radiotherapy. Conclusions: AEG1, LOX, NFKBP65cyto, PPAR and SATB1 could be used as indicators for choosing radiotherapy. COX2-RT, COX2-NonRT and some other biomarkers may provide additional help for diagnosis.

Randomized clinical trial comparing side to end vs end to end techniques for colorectal anastomosis

BACKGROUND

Low anterior resection syndrome affects 60%-90% of patients with anastomoses after colorectal resection. Consensus regarding the best anastomosis is lacking.

OBJECTIVE

To compare outcomes after end-to-end versus side-to-end anastomoses.

DESIGN

Randomized clinical trial.

SETTINGS

University hospital (April 2016-October 2017).

PATIENTS

Patients aged ≥18 years with rectal or sigmoid adenocarcinoma.

INTERVENTIONS

Patients were randomized to undergo mechanical end-to-end or side-to-end (n = 33) anastomosis after laparoscopic resection.

MAIN OUTCOME MEASURES

Primary outcome was to assess intestinal function (COREFO and LARS questionnaires) 12 months after surgery or ileostomy closure. Secondary outcomes were postoperative complications and intestinal function and quality of life (SF-36® questionnaire) at different time points after surgery or ileostomy closure.

RESULTS

No significant differences in intestinal function were observed between the two groups 12 months after surgery. Subanalysis of low-mid rectum tumors with end-to-end anastomosis yielded better function at 12 months. Postoperative complications did not differ between the two groups (p = 0.070), but reinterventions were more common in the side-to-end group (p = 0.040). Multivariate analysis found neoadjuvant treatment was independently associated with intestinal dysfunction at 12 months (β = 0.41, p = 0.033, COREFO; β = 0.41, p = 0.024, LARS).

CONCLUSIONS

End-to-end anastomosis yielded low rates of severe complications and reintervention, as well as better intestinal function at 12 months in the subgroup with tumors in the low-mid rectum.

TRIAL REGISTRATION

clinicaltrials.gov identifier: NCT02746224.

The role of readout-segmented echo-planar imaging-based diffusion-weighted imaging in evaluating tumor response of locally advanced rectal cancer after neoadjuvant chemoradiotherapy

BACKGROUND

Accurate assessment of tumor response in rectal cancer could help individualize treatment.

PURPOSE

To evaluate the role of diffusion-weighted imaging (DWI) based on readout-segmented echo-planar imaging (rs-EPI) in assessing tumor response after neoadjuvant chemoradiotherapy (CRT) in locally advanced rectal cancer (LARC).

MATERIAL AND METHODS

Sixty-three patients with LARC who received neoadjuvant CRT and surgery were enrolled retrospectively. They all underwent pre- and post-CRT magnetic resonance examinations, including DWI using rs-EPI. According to pathological results, patients were grouped as pathological complete responder (pCR, n = 16) and non-pCR (n = 47). Visual assessment of residual tumor and whole-tumor histogram analysis of pre- and post-CRT apparent diffusion coefficient (ADC) map was performed by two radiologists; tumor volume on ADC map was also recorded.

RESULTS

Overall inter-observer agreement was good for histogram analysis (ICC = 0.543-0.999). Tumor volume reduction rate on ADC map showed no significant difference between the two groups (P = 0.468). Post-CRT mean, quantile values, and their percentage changes were higher in the pCR group (all P < 0.001). Post-CRT mean value had a good diagnostic power in selecting pCR (AUC = 0.855), with a cut-off value of 1.345 × 10^-3 mm²/s, yielding a sensitivity of 83%, specificity of 81.3%. Post-CRT 95% quantile value had the highest AUC (AUC = 0.868) among quantile values, and a higher specificity (87.5% vs. 81.3%) than mean value with comparable overall diagnostic performance (P = 0.563). Visual assessment showed a sensitivity of 85.1%, specificity of 68.8% in selecting pCR.

CONCLUSION

Quantitative ADC value of rs-EPI DWI could reliably evaluate tumor response in patients with LARC. Post-CRT 95% quantile ADC value could help mean value to more accurately identify pCR.

Does IBD Portend Worse Outcomes in Patients with Rectal Cancer? A Case-Matched Analysis

BACKGROUND

Patients with IBD are at increased risk for developing colorectal cancer. However, overall survival and disease-free survival for rectal cancer alone in patients with IBD has not been reported.

OBJECTIVE

This study aimed to determine overall survival and disease-free survival for patients with rectal cancer in IBD versus non-IBD cohorts.

DESIGN

This is a retrospective cohort study.

SETTING

This study was conducted at an IBD referral center.

PATIENTS

All consecutive adult patients with IBD diagnosed with rectal cancer and at least 1 year of postsurgery follow-up were included and matched in a 1:2 fashion (age, sex, preoperative stage) with patients with rectal cancer who did not have IBD.

MAIN OUTCOMES MEASURES

Five-year overall survival and disease-free survival, 30-day postoperative complication, readmission, reoperation, and mortality rates were measured.

METHODS

Survival rates were calculated using Kaplan-Meier estimates. The association of risk factors and long-term outcomes was assessed using Cox proportion hazard models.

RESULTS

A total of 107 study patients with IBD who had rectal cancer were matched to 215 control patients; preoperative stages were as follows: 31% with stage I, 19% with stage II, 40% with stage III, and 10% with stage IV. Differences were observed (IBD vs non-IBD) in neoadjuvant chemotherapy (33.6% vs 52.6%, p = 0.001) and preoperative radiotherapy (35.5% vs 53.5%, p = 0.003). Postoperative complication rates were similar. On surgical pathology, patients with IBD had more lymphovascular invasion (12.9% vs 5.6%, p = 0.04) and positive circumferential resection margins (5.4% vs 0.9%, p = 0.03). On multivariable analysis, the diagnosis of IBD did not significantly impact long-term mortality (HR, 0.91; 95% CI, 0.53-1.57; p = 0.73) or disease-free survival (HR, 1.36; 95% CI, 0.84-2.21; p = 0.22).

LIMITATIONS

This study was limited by its retrospective design and the use of single-center data.

CONCLUSIONS

Patients have rectal cancer with IBD and without IBD have similar long-term and disease-free survival, despite lower rates of neoadjuvant treatment and higher margin positivity in patients with IBD. See Video Abstract at http://links.lww.com/DCR/B271. ¿LA ENFERMEDAD INFLAMATORIA INTESTINAL ACARREA PEORES RESULTADOS EN PACIENTES CON CÁNCER RECTAL? UN ANÁLISIS DE CASOS-COINCIDENTES: Los pacientes con enfermedad inflamatoria intestinal (EII) tienen un mayor riesgo de desarrollar cáncer colorrectal. Sin embargo, no se ha informado la supervivencia general y la supervivencia libre de enfermedad para el cáncer rectal solo en pacientes con EII.Determinar la supervivencia general y la supervivencia libre de enfermedad para pacientes con cáncer rectal en cohortes con EII versus sin EII.Estudio de cohorte retrospectivo.Centro de referencia para enfermedad inflamatoria intestinal.todos los pacientes adultos con EII diagnosticados con cáncer rectal, consecutives, y al menos un año de seguimiento postoperatorio se incluyeron y se emparejaron de manera 1: 2 (edad, sexo, etapa preoperatoria) con pacientes con cáncer rectal sin EII.Se midieron la supervivencia general a cinco años y la supervivencia libre de enfermedad, complicaciones postoperatorias a los 30 días, reingreso, reoperación y tasas de mortalidad.Las tasas de supervivencia se calcularon utilizando estimaciones de Kaplan-Meier. La asociación de factores de riesgo y resultados a largo plazo se evaluó mediante modelos de riesgo de proporción de Cox.Un total de 107 pacientes con EII y cáncer rectal se compararon con 215 pacientes de control; las etapas preoperatorias fueron las siguientes: 31% de Etapa I, 19% de Etapa II, 40% de Etapa III y 10% de Etapa IV. Se observaron diferencias (EII versus no EII) en quimioterapia neoadyuvante (33.6% frente a 52.6%, p = 0.001) y radioterapia preoperatoria (35.5% frente a 53.5%, p = 0.003). Las tasas de complicaciones postoperatorias fueron similares. En la patología quirúrgica, los pacientes con EII tuvieron más invasión linfovascular (12.9% frente a 5.6%, p = 0.04) y márgenes de resección circunferencial positivos (5.4% frente a 0.9%, p = 0.03). En el análisis multivariable, el diagnóstico de EII no tuvo un impacto significativo en la mortalidad a largo plazo (HR 0.91; IC del 95%: 0.53-1.57, p = 0.73) o la supervivencia libre de enfermedad (HR 1.36; IC del 95%: 0.84-2.21, p = 0.22)Diseño retrospectivo, centro único de datos.Los pacientes con EII y sin EII con cáncer rectal tienen una supervivencia similar a largo plazo y libre de enfermedad, a pesar de las tasas más bajas de tratamiento sneoadyuvante y un mayor margen positivo en pacientes con EII. Consulte Video Resumen en http://links.lww.com/DCR/B271.

Advances in the treatment of locally advanced rectal cancer

Locally advanced rectal cancer requires multidisciplinary care. In the United States, most patients are treated with neoadjuvant chemoradiation delivered over 25‐28 days, total mesorectal excision, and 4 months of adjuvant chemotherapy. While effective, this trimodal approach is arduous. Alternative approaches have emerged to streamline treatment without sacrificing oncologic outcomes. These approaches include preoperative chemotherapy with selective use of radiation, short‐course radiotherapy delivered over 5 days, and total neoadjuvant therapy with attempted nonoperative organ‐preserving management (watch and wait). Ongoing trials are assessing the efficacies of these approaches in combination with various risk stratification strategies.

Accuracy of high-resolution rectal magnetic resonance imaging re-staging with histopathology in locally advanced rectal cancer after neoadjuvant chemoradiotherapy

BACKGROUND/OBJECTIVE

Re-staging of locally advanced rectal cancer (LARC) following neoadjuvant chemoradiotherapy (NCRT) is a crucial step in surgical decision-making. Currently, MRI is the imaging of choice for evaluation of LARCs, however, the diagnostic accuracy of this modality is inconsistent. In this study, we evaluated the diagnostic accuracy of MRI in LARC and analyzed the factors that influenced the accuracy.

METHODS

The records of 133 patients diagnosed with LARC who were operated on during 2011-2018 were retrospectively reviewed. All patients received NCRT followed by re-staging based on high-resolution rectal MRI. The MRI results were analyzed for their yT and yN accuracy and anal sphincter involvement and compared with the related histopathological studies after definitive surgery.

RESULTS

Re-staging MRIs gave overall accuracy in both the yT stage and yN evaluation of 85% (K 0.45 and 0.21, respectively). The MRI tended to overstaging for tumor invasion and understaging for lymph node involvement (sign test p-values = 0.017 and 0.022, respectively.) The highest accuracy of the yT stage was yT4b (93%, K 0.71). The study found that larger tumors (>3 cm) were associated with significantly higher accuracy in the yT readings while lack of lymphovascular invasion was associated with higher accuracy in the yN readings. The negative predictive value for anal sphincter involvement was 100%.

CONCLUSION

MRI has limited accuracy in post-NCRT re-staging in LARC, tending to give overstaged yT readings and understaged yN readings. An MRI exclusion of sphincteric involvement is highly reliable.

Avoidance of Overtreatment of Rectal Cancer by Selective Chemoradiotherapy: Results of the Optimized Surgery and MRI-Based Multimodal Therapy Trial

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) in patients with rectal cancer carries a high risk of adverse effects. The aim of this study was to examine the selective application of nCRT based on patient risk profile, as determined by MRI, to find the optimal range between undertreatment and overtreatment.

STUDY DESIGN

In this prospective multicenter observational study, nCRT before total mesorectal excision (TME) was indicated in high-risk patients with involved or threatened mesorectal fascia (≤1 mm), or cT4 or cT3 carcinomas of the lower rectal third. All other patients received primary surgery.

RESULTS

Of the 1,093 patients, 878 (80.3%) were treated according to the protocol, 526 patients (59.9%) underwent primary surgery, and 352 patients (40.1%) underwent nCRT followed by surgery. The 3-year locoregional recurrence (LR) rate was 3.1%. Of 604 patients with clinical stages II and III, 267 (44.2%) had primary surgery; 337 (55.8%) received nCRT followed by TME. The 3-year LR rate was 3.9%, without significant differences between groups. In patients with clinical stages II and III who underwent primary surgery, 27.3% were diagnosed with pathological stage I.

CONCLUSIONS

The results justify the restriction of nCRT to high-risk patients with rectal cancer classified by pretreatment MRI. Provided that a high-quality MRI diagnosis, TME surgery, and standardized examination of the resected specimen are performed, nCRT, with its adverse effects, costs, and treatment time can be avoided in more than 40% of patients with stage II or III rectal cancer with minimal risk of undertreatment. (clinicaltrials.gov NCT325649).

Oncologic Risk of Rectal Preservation Against Medical Advice After Chemoradiotherapy for Rectal Cancer: A Multicenter Comparative Cross-Sectional Study with Rectal Preservation as Supported by Surgeon

BACKGROUND

Rectal preservation against medical advice after neoadjuvant chemoradiotherapy for rectal cancer may increase oncologic uncertainty. This study aimed to compare the oncologic outcomes of patients undergoing rectal preservation as intended by the surgeon, and the outcomes of patients refusing rectal resection against medical advice.

METHODS

The study population consisted of patients in whom the rectum was preserved after neoadjuvant chemoradiotherapy for clinical stage I-III mid or low rectal cancer between May 2003 and August 2017 (n = 2883); these patients were divided into those in whom rectal preservation was intended by their surgeon (intended rectal preservation, group A, n = 41) and those in whom the rectum was not resected against medical advice (unintended rectal preservation, group B, n = 101), defined as non-operative management or local excision.

RESULTS

The tumor distance, age, and performance status of patients were not significantly different between the groups, while the clinical T stage before chemoradiotherapy was lower in group A than in group B (P < 0.001). During the median follow-up period of 34 months (interquartile range 18.0-72.0 months), the 3-year overall survival in group B (59.7%) was worse than that in group A (90.1%; P < 0.001), and 80.2% of group B patients had residual or unknown disease status.

CONCLUSIONS

This study showed that unintended rectal preservation increases oncologic risk after neoadjuvant chemoradiotherapy for rectal cancer regardless of short-term follow-up. Therefore, these findings could be shared with rectal cancer patients who choose to ignore medical advice after chemoradiotherapy to preserve their rectum.

Response Assessment with MRI after Chemoradiotherapy in Rectal Cancer: Current Evidences

Baseline magnetic resonance imaging (MRI) has become the primary staging modality for surgical plans and stratification of patient populations for more efficient neoadjuvant treatment. Patients who exhibit a complete response to chemoradiotherapy (CRT) may achieve excellent local tumor control and better quality of life with organ-preserving treatments such as local excision or even watch-and-wait management. Therefore, the evaluation of tumor response is a key factor for determining the appropriate treatment following CRT. Although post-CRT MRI is generally accepted as the first-choice method for evaluating treatment response after CRT, its application in the clinical decision process is not fully validated. In this review, we will discuss various oncologic treatment options from radical surgical technique to organ-preservation strategies for achieving better cancer control and improved quality of life following CRT. In addition, the current status of post-CRT MRI in restaging rectal cancer as well as the main imaging features that should be evaluated for treatment planning will also be described for the tailored treatment.

Selective lateral lymph node dissection after neoadjuvant chemoradiotherapy in rectal cancer

BACKGROUND

Lateral lymph node metastasis is one of the leading causes of local recurrence in patients with advanced mid or low rectal cancer. Neoadjuvant chemoradiotherapy (NCRT) can effectively reduce the postoperative recurrence rate; thus, NCRT with total mesorectal excision (TME) is the most widely accepted standard of care for rectal cancer. The addition of lateral lymph node dissection (LLND) after NCRT remains a controversial topic.

AIM

To investigate the surgical outcomes of TME plus LLND, and the possible risk factors for lateral lymph node metastasis after NCRT.

METHODS

This retrospective study reviewed 89 consecutive patients with clinical stage II-III mid or low rectal cancer who underwent TME and LLND from June 2016 to October 2018. In the NCRT group, TME plus LLND was performed in patients with short axis (SA) of the lateral lymph node greater than 5 mm. In the non-NCRT group, TME plus LLND was performed in patients with SA of the lateral lymph node greater than 10 mm. Data regarding patient demographics, clinical workup, surgical procedure, complications, and outcomes were collected. Multivariate logistic regression analysis was performed to evaluate the possible risk factors for lateral lymph node metastasis in NCRT patients.

RESULTS

LLN metastasis was pathologically confirmed in 35 patients (39.3%): 26 (41.3%) in the NCRT group and 9 (34.6%) in the non-NCRT group. The most common site of metastasis was around the obturator nerve (21/35) followed by the internal iliac artery region (12/35). In the NCRT patients, 46% of patients with SA of LLN greater than 7 mm were positive. The postoperative 30-d mortality rate was 0%. Two (2.2%) patients suffered from lateral local recurrence in the 2-year follow up. Multivariate analysis showed that cT4 stage (odds ratio [OR] = 5.124, 95% confidence interval [CI]: 1.419-18.508; P = 0.013), poor differentiation type (OR = 4.014, 95%CI: 1.038-15.520; P = 0.044), and SA ≥ 7 mm (OR = 7.539, 95%CI: 1.487-38.214; P = 0.015) were statistically significant risk factors associated with LLN metastasis.

CONCLUSION

NCRT is not sufficient as a stand-alone therapy to eradicate LLN metastasis in lower rectal cancer patients and surgeons should consider performing selective LLND in patients with greater LLN SA diameter, poorer histological differentiation, or advanced T stage. Selective LLND for NCRT patients can have a favorable oncological outcome.

Clinicopathologic determinants of pathologic treatment response in neoadjuvant treated rectal adenocarcinoma

Neoadjuvant treatment (NAT) followed by total mesorectal excision is currently considered the standard of treatment for rectal adenocarcinoma. The degree of pathologic treatment response (pTR) correlates significantly with the recurrence free survival and overall survival (OS). However, it remains unclear which clinical and pathologic factors are associated with a more robust response to NAT, including showing pathologic complete response (pCR). Chemokine receptor 4 (CXCR4) overexpression has been associated with unfavorable OS in some studies. In this study, we sought to evaluate the clinicopathologic determinants of pTR in neoadjuvant treated rectal adenocarcinoma (NAT-RA). We retrospectively identified 91 patients who underwent pre-treatment diagnostic biopsy, NAT, and surgical resection at our institution. The archival slides were reviewed for pathologic features in the pre-treatment biopsies and for assessment of pTR in the resection specimens according to the current College of American Pathologist (CAP)'s guidelines. pCR was obtained in 16.5% of the cases, whereas 20.9% had near pCR, 30.8% had partial response, and 31.9% had a poor/no response. CXCR4 immunohistochemical analysis was also performed on the pre-treatment biopsies. Lower pre-treatment cT-stage (p = 0.019) and pre-treatment AJCC cTNM stage groups (p = 0.004), longer time interval between completion of NAT and resection (p = 0.022), and presence of tumor-infiltrating lymphocytes in the pre-treatment biopsies (p = 0.019) were significantly associated with a better pTR. CXCR4 nuclear expression was associated with a lower percentage of residual tumor (p = 0.036). Pre-treatment CEA levels, tumor differentiation, CAP treatment response groups and lower percentage of residual tumor were associated with a better OS.

Knowledge-based automatic optimization of adaptive early-regression-guided VMAT for rectal cancer

PURPOSE

To implement a knowledge-based (KB) optimization strategy to our adaptive (ART) early-regression guided boosting technique in neo-adjuvant radio-chemotherapy for rectal cancer.

MATERIAL AND METHODS

The protocol consists of a first phase delivering 27.6 Gy to tumor/lymph-nodes (2.3 Gy/fr-PTV₁), followed by the ART phase concomitantly delivering 18.6 Gy (3.1 Gy/fr) and 13.8 Gy (2.3 Gy/fr) to the residual tumor (PTV_ART) and to PTV₁ respectively. PTV_ART is obtained by expanding the residual GTV, as visible on MRI at fraction 9. Forty plans were used to generate a KB-model for the first phase using the RapidPlan tool. Instead of building a new model, a robust strategy scaling the KB-model to the ART phase was applied. Both internal and external validation were performed for both phases: all automatic plans (RP) were compared in terms of OARs/PTVs parameters against the original plans (RA).

RESULTS

The resulting automatic plans were generally better than or equivalent to clinical plans. Of note, V_30Gy and V_40Gy were significantly improved in RP plans for bladder and bowel; gEUD analysis showed improvement for KB-modality for all OARs, up to 3 Gy for the bowel.

CONCLUSIONS

The KB-model generated for the first phase was robust and it was also efficiently adapted to the ART phase. The performance of automatically generated plans were slightly better than the corresponding manual plans for both phases.

A Review on Curability of Cancers: More Efforts for Novel Therapeutic Options Are Needed

Cancer remains a major cause of death globally. Given its relapsing and fatal features, curing cancer seems to be something hardly possible for the majority of patients. In view of the development in cancer therapies, this article summarizes currently available cancer therapeutics and cure potential by cancer type and stage at diagnosis, based on literature and database reviews. Currently common cancer therapeutics include surgery, chemotherapy, radiotherapy, targeted therapy, and immunotherapy. However, treatment with curative intent by these methods are mainly eligible for patients with localized disease or treatment-sensitive cancers and therefore their contributions to cancer curability are relatively limited. The prognosis for cancer patients varies among different cancer types with a five-year relative survival rate (RSR) of more than 80% in thyroid cancer, melanoma, breast cancer, and Hodgkin's lymphoma. The most dismal prognosis is observed in patients with small-cell lung cancer, pancreatic cancer, hepatocellular carcinoma, oesophagal cancer, acute myeloid leukemia, non-small cell lung cancer, and gastric cancer with a five-year RSR ranging between 7% and 28%. The current review is intended to provide a general view about how much we have achieved in curing cancer as regards to different therapies and cancer types. Finally, we propose a small molecule dual-targeting broad-spectrum anticancer strategy called OncoCiDia, in combination with emerging highly sensitive liquid biopsy, with theoretical curative potential for the management of solid malignancies, especially at the micro-cancer stage.

Implementation of an Enhanced Recovery Protocol Is Associated With On-Time Initiation of Adjuvant Chemotherapy in Colorectal Cancer

BACKGROUND

Delayed initiation of adjuvant chemotherapy negatively impacts long-term survival in patients with colorectal cancer. Colorectal enhanced recovery protocols result in decreased complications and length of stay; however, the impact of enhanced recovery on the timing of adjuvant chemotherapy remains unknown.

OBJECTIVE

This study aimed to identify factors associated with on-time delivery of adjuvant chemotherapy after colorectal cancer surgery, hypothesizing that implementation of an enhanced recovery protocol would result in more patients receiving on-time chemotherapy.

DESIGN

This was a retrospective cohort study comparing the rate of on-time adjuvant chemotherapy delivery after colorectal cancer resection before and after implementation of an enhanced recovery protocol.

SETTINGS

The study was conducted at a large academic medical center.

PATIENTS

All of the patients who underwent nonemergent colorectal cancer resections for curative intent from January 2010 to June 2017, excluding patients who had no indication for adjuvant chemotherapy, had received preoperative systemic chemotherapy, or did not have medical oncology records available were included.

MAIN OUTCOME MEASURES

Patients before and enhanced recovery were compared, with the rate of on-time adjuvant chemotherapy delivery as the primary outcome. Adjuvant chemotherapy delivery was considered on time if initiated ≤8 weeks postoperatively, and treatment was considered delayed or omitted if initiated >8 weeks postoperatively (delayed) or never received (omitted). Multivariable logistic regression identified predictors of on-time chemotherapy delivery.

RESULTS

A total of 363 patients met inclusion criteria, with 189 patients (52.1%) undergoing surgery after enhanced recovery implementation. Groups differed in laparoscopic approach and median procedure duration, both of which were higher after enhanced recovery. Significantly more patients received on-time chemotherapy after enhanced recovery implementation (p = 0.007). Enhanced recovery was an independent predictor of on-time adjuvant chemotherapy (p = 0.014).

LIMITATIONS

The study was limited by its retrospective and nonrandomized before-and-after design.

CONCLUSIONS

Enhanced recovery was associated with receiving on-time adjuvant chemotherapy. As prompt initiation of adjuvant chemotherapy improves survival in colorectal cancer, future investigation of long-term oncologic outcomes is necessary to evaluate the potential impact of enhanced recovery on survival. See Video Abstract at http://links.lww.com/DCR/B21. LA IMPLEMENTACIÓN DE UN PROTOCOLO DE RECUPERACIÓN ACELERADA SE ASOCIA CON EL INICIO A TIEMPO DE QUIMIOTERAPIA ADYUVANTE EN CÁNCER COLORRECTAL:: El inicio tardío de la quimioterapia adyuvante afecta negativamente la supervivencia a largo plazo en pacientes con cáncer colorrectal. Los protocolos de recuperación acelerada colorrectales dan lugar a una disminución de las complicaciones y la duración de estancia hospitalaria; sin embargo, el impacto de la recuperación acelerada en el momento de inicio de quimioterapia adyuvante sigue siendo desconocido.Este estudio tuvo como objetivo identificar los factores asociados con la administración a tiempo de la quimioterapia adyuvante después de la cirugía de cáncer colorrectal, con la hipótesis de que la implementación de un protocolo de recuperación acelerada daría lugar a que más pacientes reciban quimioterapia a tiempo.Estudio de cohorte retrospectivo que compara la tasa de administración de quimioterapia adyuvante a tiempo después de la resección del cáncer colorrectal antes y después de la implementación de un protocolo de recuperación acelerada.Centro médico académico grande.Todos los pacientes que se sometieron a resecciones de cáncer colorrectal no emergentes con intención curativa desde enero de 2010 hasta junio de 2017, excluyendo a los pacientes que no tenían indicación de quimioterapia adyuvante, que recibieron quimioterapia sistémica preoperatoria o no tenían registros médicos de oncología disponibles.Los pacientes se compararon antes y después de la implementación de la recuperación acelerada, con la tasa de administración de quimioterapia adyuvante a tiempo como el resultado primario. La administración de quimioterapia adyuvante se consideró a tiempo si se inició ≤8 semanas después de la operación, y el tratamiento se consideró retrasado / omitido si se inició> 8 semanas después de la operación (retrasado) o nunca fue recibido (omitido). La regresión logística multivariable identificó predictores de administración de quimioterapia a tiempo.363 pacientes cumplieron con los criterios de inclusión, con 189 (52.1%) pacientes sometidos a cirugía después de la implementación de recuperación acelerada. Los grupos difirieron en el abordaje laparoscópico y la duración media del procedimiento; ambos factores fueron mayores después de la recuperación acelerada. Significativamente más pacientes recibieron quimioterapia a tiempo después de la implementación de recuperación acelerada (p = 0.007). La recuperación acelerada fue un factor predictivo independiente de quimioterapia adyuvante a tiempo (p = 0.014).Diseño retrospectivo, tipo ¨antes y después¨ no aleatorizado.La recuperación acelerada se asoció con la recepción de quimioterapia adyuvante a tiempo. Debido a que el inicio rápido de la quimioterapia adyuvante mejora la supervivencia en el cáncer colorrectal, en el futuro será necesario investigar los resultados oncológicos a largo plazo para evaluar el impacto potencial de la recuperación acelerada en la supervivencia. Vea el Resumen en Video en http://links.lww.com/DCR/B21.

Retrospective review of total neoadjuvant therapy

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) followed by resection and postoperative multi-agent chemotherapy (maChT) is the standard of care for locally advanced rectal cancer. Using this approach, maChT administration can be delayed for several months, leading to concern for distant metastases. To counteract this, a novel treatment approach known as total neoadjuvant therapy (TNT) has gained popularity, in which patients receive both maChT and nCRT prior to resection. We utilized the National Cancer Database to examine temporal trends in TNT usage, and any potential effect on survival.

AIM

To study the temporal trends in the usage of TNT and evaluate its efficacy compared to neoadjuvant chemoradiation.

METHODS

We queried the National Cancer Database for patients with locally advanced rectal cancer, Stage II-III, from 2004-2015 treated with nCRT or TNT. TNT was defined as maChT initiated ≥ 90 d prior to nCRT initiation. Overall survival was calculated from the date of diagnosis to the date of last contact or death using Kaplan-Meier curves to present the cumulative probability of survival, with log-rank statistics to assess significance. Multivariable cox regression was used to identify predictors of survival and propensity score analysis accounted for bias.

RESULTS

We identified 9066 eligible patients, with 8812 and 254 patients receiving neoadjuvant chemoradiation followed by maChT and TNT, respectively. Nodal involvement, stage III disease, and treatment in recent years were predictive of TNT use. There was greater use of TNT with more advanced stage, specifically > 1 node involved (odds ratio [OR] = 2.88, 95% confidence interval [CI]: 2.11-3.93, P < 0.01) and stage III disease (OR = 2.88, 95%CI: 2.11-3.93, P < 0.01). From 2010 to 2012 the use of TNT increased (OR = 2.41, 95%CI: 1.27-4.56, P < 0.01) with a greater increase from 2013 to 2015 (OR = 6.62, 95%CI: 3.57-12.25, P < 0.01). Both the TNT and neoadjuvant chemoradiation arms had a similar 5-year survival at 76% and 78% respectively. Multivariable analysis with propensity score demonstrated that increased age, high comorbidity score, higher grade, African American race, and female gender had worse overall survival.

CONCLUSION

Our data demonstrates a rising trend in TNT use, particularly in patients with worse disease. Patients treated with TNT and nCRT had similar survival. Randomized trials evaluating TNT are underway.

A rectal cancer organoid platform to study individual responses to chemoradiation

Rectal cancer (RC) is a challenging disease to treat that requires chemotherapy, radiation and surgery to optimize outcomes for individual patients. No accurate model of RC exists to answer fundamental research questions relevant to patients. We established a biorepository of 65 patient-derived RC organoid cultures (tumoroids) from patients with primary, metastatic or recurrent disease. RC tumoroids retained molecular features of the tumors from which they were derived, and their ex vivo responses to clinically relevant chemotherapy and radiation treatment correlated with the clinical responses noted in individual patients' tumors. Upon engraftment into murine rectal mucosa, human RC tumoroids gave rise to invasive RC followed by metastasis to lung and liver. Importantly, engrafted tumors displayed the heterogenous sensitivity to chemotherapy observed clinically. Thus, the biology and drug sensitivity of RC clinical isolates can be efficiently interrogated using an organoid-based, ex vivo platform coupled with in vivo endoluminal propagation in animals.

Oncological and Survival Outcomes in Watch and Wait Patients With a Clinical Complete Response After Neoadjuvant Chemoradiotherapy for Rectal Cancer: A Systematic Review and Pooled Analysis

OBJECTIVE

The aim of this study was to evaluate the oncological and survival outcomes of a Watch and Wait policy in rectal cancer after a clinical complete response (cCR) following neoadjuvant chemoradiotherapy.

BACKGROUND

The detection of a cCR after neoadjuvant treatment may facilitate a nonoperative approach in selected patients. However, the long-term safety of this strategy remains to be validated.

METHOD

This is a systematic review of the literature to determine the oncological outcomes in Watch and Wait patients. The primary outcome was the cumulative rate of local regrowth, success of salvage surgery, and incidence of metastases. We also evaluated survival outcomes. A pooled analysis of manually extracted summary statistics from individual studies was carried out using inverse variance weighting.

RESULTS

Seventeen studies comprising 692 patients were identified; incidence of cCR was 22.4% [95% confidence interval (CI),14.3-31.8]. There were 153 (22.1%) local regrowths, of which 96% (n = 147/153) manifested in the first 3 years of surveillance. The 3-year cumulative risk of local regrowth was 21.6% (95% CI, 16.0-27.8). Salvage surgery was performed in 88% of patients, of which 121 (93%) had a complete (R0) resection. Fifty-seven metastases (8.2%) were detected, and 35 (60%) were isolated without evidence of synchronous regrowths; 3-year incidence was 6.8% (95% CI, 4.1-10.2). The 3-year overall survival was 93.5% (95% CI, 90.2-96.2).

CONCLUSION

In rectal cancer patients with a cCR following neoadjuvant chemoradiotherapy, a Watch and Wait policy appears feasible and safe. Robust surveillance with early detection of regrowths allows a high rate of successful salvage surgery, without an increase in the risk of systemic disease, or adverse survival outcomes.

The impact of total neo-adjuvant treatment on nonoperative management in patients with locally advanced rectal cancer: The evaluation of 66 cases

BACKGROUND

The study aimed to assess if adherence to a total-neoadjuvant-treatment (TNT) protocol followed by observation(watch-and-wait) led to the successful nonoperative-management of low-rectal-cancer.

METHODS

In this study, patients with primary, resectable-T3-T4, N0-N1 distal-rectal-adenocarcinoma underwent-chemoradiotherapy + consolidation-chemotherapy (TNT). During the-TNT-period, endoscopy, MRI, and FDG-PET/CT were performed. We allocated patients with complete-clinical-tumor-regression, who underwent endoscopy every two months, MRI every-four-months, and PET/CT every-six-months-after-treatment, to the observation-group(OG). All other patients were referred for surgery. The OG was followed-up. The primary endpoint was local tumor-ecurrence after allocation to the OG.

RESULTS

Between 2015 and 2018, we enrolled 66-patients. Of 60-patients who were eligible to participate, 39 had complete-clinical-response(cCR) and were allocated to the OG, six underwent local-excision (LE), and 15 underwent total-mesorectal-excision (TME). The median follow-up duration was 22 (9-42) months. The local-recurrence-rate in the OG was 15.3%, and the LE and TME rates were 16.6% and 0%, respectively. All recurrence cases were salvaged through either LE or TME. The-distant-metastasis rate was 5.1%, 16.6%, and 12.5% in the OG, LE, and TME groups, respectively. The endoscopic negative-predictive-value(NPV) was 50%, and the positive-predictive-value(PPV) was 76.9% in the surgery group (LE + TME). MRI; NPV-50%, PPV-76.9%. PET/CT; NPV-100%, PPV-93.3%. Six patients(28.57%) from surgery group achieved complete pathological response (cPR).

CONCLUSION

Our results indicated a high proportion of selected-rectal-cancers with-cCR after neo-adjuvant-therapy could potentially be managed non-operatively, and major surgery may be avoided.

Accurate outcome prediction after neo-adjuvant radio-chemotherapy for rectal cancer based on a TCP-based early regression index

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A TCP-based early regression index (ERI_TCP) was previously introduced.

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ERI_TCP was associated to improved survival after neo-adjuvant therapy for rectal cancer.

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Distant-metastasis-free survival was predicted by ERI_TCP and 5-FU dose.

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The resulting AUC (0.86) was significantly higher than models not including T ERI_TCP.

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ERI_TCP is a promising tool for therapy personalization.

Background and purpose

An early tumor regression index (ERI_TCP) was previously introduced and found to predict pathological response after neo-adjuvant radio-chemotherapy of rectal cancer. ERI_TCP was tested as a potential biomarker in predicting long-term disease-free survival.

Materials and methods

Data of 65 patients treated with an early regression-guided adaptive boosting technique (ART) were available. Overall, loco-regional relapse-free and distant metastasis-free survival (OS, LRFS, DMFS) were considered. Patients received 41.4 Gy in 18 fractions (2.3 Gy/fr), including ART concomitant boost on the residual GTV during the last 6 fractions (3 Gy/fr, D_mean: 45.6 Gy). Chemotherapy included oxaliplatin and 5-fluorouracil (5-FU). T2-weighted MRI taken before (MRI_pre) and at half therapy (MRI_half) were available and GTVs were contoured (V_pre, V_half). The parameter ERI_TCP = −ln[(1 − (V_half/V_pre))^Vpre] was calculated for all patients. Cox regression models were assessed considering several clinical and histological variables. Cox models not including/including ERI_TCP (CONV_model and REGR_model respectively) were assessed and their discriminative power compared.

Results

At a median follow-up of 47 months, OS, LRFS and DMFS were 94%, 95% and 78%. Due to too few events, multivariable analyses focused on DMFS: the resulting CONV_model included pathological complete remission or clinical complete remission followed by surgery refusal (HR: 0.15, p = 0.07) and 5-FU dose >90% (HR: 0.29, p = 0.03) as best predictors, with AUC = 0.75. REGR_model included ERI_TCP (HR: 1.019, p < 0.0001) and 5-FU dose >90% (HR: 0.18, p = 0.005); AUC was 0.86, significantly higher than CONV_model (p = 0.05). Stratifying patients according to the best cut-off value for ERI_TCP and to 5-FU dose (> vs <90%) resulted in 47-month DMFS equal to 100%/69%/0% for patients with two/one/zero positive factors respectively (p = 0.0002). ERI_TCP was also the only variable significantly associated to OS (p = 0.01) and LRFS (p = 0.03).

Conclusion

ERI_TCP predicts long-term DMFS after radio-chemotherapy for rectal cancer: an independent impact of the 5-FU dose was also found. This result represents a first step toward application of ERI_TCP in treatment personalization: additional confirmation on independent cohorts is warranted.

CT Staging to Triage Selection of Patients With Poor-Prognosis Rectal Cancer for Neoadjuvant Treatment

OBJECTIVE. The purpose of this study was to evaluate CT as a screening tool for determining high risk of local recurrence of rectal tumors in a scenario of limited MRI availability. MATERIALS AND METHODS. Data were retrospectively analyzed for 180 consecutively registered patients with rectal adenocarcinoma and no previous treatment who underwent baseline CT and MRI staging within 30 days of each other. Two radiologists independently reviewed CT and MR images. CT scans were interpreted in multiplanar reformation. High risk of local recurrence was based on the MRI reference standard: T3cd (more than 5 mm of mesorectal fat infiltration) or T4 disease, N2 nodal status, mesorectal fascia involvement, extramural venous invasion, or positive pelvic sidewall nodes. The performance of CT for determination of high risk of local tumor recurrence was evaluated. RESULTS. Among the 180 patients 128 (71%) met MRI criteria for high risk of local recurrence. CT sensitivity was 84.4% (108/128) and specificity was 78.8% (41/52). The positive predictive value (PPV) of any high-risk CT feature was 90.7% (108/119). When T status was considered, the sensitivity of CT was 75.2% (79/105), specificity was 90.7% (68/75), and PPV was 91.9% (79/86). When tumors within 5.0 cm of the anal verge were excluded, sensitivity was 89.5% (51/57), specificity was 85.7% (24/28), and PPV was 92.7% (51/55). Using CT for disease staging could reduce MRI use by 66%. CONCLUSION. Tumors at high risk of local recurrence can be identified with CT without baseline MRI. Use of CT rather than MRI could markedly reduce costs of baseline staging and shorten time to initiation of neoadjuvant treatment.

Genome-wide RNAi Screening Identifies RFC4 as a Factor That Mediates Radioresistance in Colorectal Cancer by Facilitating Nonhomologous End Joining Repair

PURPOSE

Neoadjuvant chemoradiotherapy (neoCRT) is a standard treatment for locally advanced rectal cancer (LARC); however, resistance to chemoradiotherapy is one of the main obstacles to improving treatment outcomes. The goal of this study was to identify factors involved in the radioresistance of colorectal cancer and to clarify the underlying mechanisms.

EXPERIMENTAL DESIGN

A genome-wide RNAi screen was used to search for candidate radioresistance genes. After RFC4 knockdown or overexpression, colorectal cancer cells exposed to X-rays both in vitro and in a mouse model were assayed for DNA damage, cytotoxicity, and apoptosis. Moreover, the regulatory effects and mechanisms of RFC4 in DNA repair were investigated in vitro. Finally, the relationships between RFC4 expression and clinical parameters and outcomes were investigated in 145 patients with LARC receiving neoCRT.

RESULTS

RFC4, NCAPH, SYNE3, LDLRAD2, NHP2, and FICD were identified as potential candidate radioresistance genes. RFC4 protected colorectal cancer cells from X-ray-induced DNA damage and apoptosis in vitro and in vivo. Mechanistically, RFC4 promoted nonhomologous end joining (NHEJ)-mediated DNA repair by interacting with Ku70/Ku80 but did not affect homologous recombination-mediated repair. Higher RFC4 expression in cancer tissue was associated with weaker tumor regression and poorer prognosis in patients with LARC treated with neoCRT, which likely resulted from the effect of RFC4 on radioresistance, not chemoresistance.

CONCLUSIONS

RFC4 was identified as a radioresistance factor that promotes NHEJ-mediated DNA repair in colorectal cancer cells. In addition, the expression level of RFC4 predicted radiotherapy responsiveness and the outcome of neoadjuvant radiotherapy in patients with LARC.

Assessment of a Watch-and-Wait Strategy for Rectal Cancer in Patients With a Complete Response After Neoadjuvant Therapy

Importance

The watch-and-wait (WW) strategy aims to spare patients with rectal cancer unnecessary resection.

Objective

To analyze the outcomes of WW among patients with rectal cancer who had a clinical complete response to neoadjuvant therapy.

Design, Setting, and Participants

This retrospective case series analysis conducted at a comprehensive cancer center in New York included patients who received a diagnosis of rectal adenocarcinoma between January 1, 2006, and January 31, 2015. The median follow-up was 43 months. Data analyses were conducted from June 1, 2016, to October 1, 2018.

Exposures

Patients had a clinical complete response after completing neoadjuvant therapy and agreed to a WW strategy of active surveillance and possible salvage surgery (n = 113), or patients underwent total mesorectal excision and were found to have a pathologic complete response (pCR) at resection (n = 136).

Main Outcomes and Measures

Kaplan-Meier estimates were used for analyses of local regrowth and 5-year rates of overall survival, disease-free survival, and disease-specific survival.

Results

Compared with the 136 patients in the pCR group, the 113 patients in the WW group were older (median [range], 67.2 [32.1-90.9] vs 57.3 [25.0-87.9] years, P < .001) with cancers closer to the anal verge (median [range] height from anal verge, 5.5 [0.0-15.0] vs 7.0 [0.0-13.0] cm). All 22 local regrowths in the WW group were detected on routine surveillance and treated by salvage surgery (20 total mesorectal excisions plus 2 transanal excisions). Pelvic control after salvage surgery was maintained in 20 of 22 patients (91%). No pelvic recurrences occurred in the pCR group. Rectal preservation was achieved in 93 of 113 patients (82%) in the WW group (91 patients with no local regrowths plus 2 patients with local regrowths salvaged with transanal excision). At 5 years, overall survival was 73% (95% CI, 60%-89%) in the WW group and 94% (95% CI, 90%-99%) in the pCR group; disease-free survival was 75% (95% CI, 62%-90%) in the WW group and 92% (95% CI, 87%-98%) in the pCR group; and disease-specific survival was 90% (95% CI, 81%-99%) in the WW group and 98% (95% CI, 95%-100%) in the pCR group. A higher rate of distant metastasis was observed among patients in the WW group who had local regrowth vs those who did not have local regrowth (36% vs 1%, P < .001).

Conclusions and Relevance

A WW strategy for select rectal cancer patients who had a clinical complete response after neoadjuvant therapy resulted in excellent rectal preservation and pelvic tumor control; however, in the WW group, worse survival was noted along with a higher incidence of distant progression in patients with local regrowth vs those without local regrowth.

Role of the Interval from Completion of Neoadjuvant Therapy to Surgery in Postoperative Morbidity in Patients with Locally Advanced Rectal Cancer

BACKGROUND

Increasing the interval from completion of neoadjuvant therapy to surgery beyond 8 weeks is associated with increased response of rectal cancer to neoadjuvant therapy. However, reports are conflicting on whether extending the time to surgery is associated with increased perioperative morbidity.

METHODS

Patients who presented with a tumor within 15 cm of the anal verge in 2009-2015 were grouped according to the interval between completion of neoadjuvant therapy and surgery: < 8 weeks, 8-12 weeks, and 12-16 weeks.

RESULTS

Among 607 patients, the surgery was performed at < 8 weeks in 317 patients, 8-12 weeks in 229 patients, and 12-16 weeks in 61 patients. Patients who underwent surgery at 8-12 weeks and patients who underwent surgery at < 8 weeks had comparable rates of complications (37% and 44%, respectively). Univariable analysis identified male sex, earlier date of diagnosis, tumor location within 5 cm of the anal verge, open operative approach, abdominoperineal resection, and use of neoadjuvant chemoradiotherapy alone to be associated with higher rates of complications. In multivariable analysis, male sex, tumor location within 5 cm of the anal verge, open operative approach, and neoadjuvant chemoradiotherapy administered alone were independently associated with the presence of a complication. The interval between neoadjuvant therapy and surgery was not an independent predictor of postoperative complications.

CONCLUSIONS

Delaying surgery beyond 8 weeks from completion of neoadjuvant therapy does not appear to increase surgical morbidity in rectal cancer patients.

Prognostic value of tumour-infiltrating CD8+ lymphocytes in rectal cancer after neoadjuvant chemoradiation: is indoleamine-2,3-dioxygenase (IDO1) a friend or foe?

The prognostic value of the local immune phenotype in patients with colorectal cancer has been extensively studied. Neoadjuvant radiotherapy and/or chemotherapy may potentially influence these immune responses. In this study, we examined the prognostic role of indoleamine-2,3-Dioxygenase (IDO1) and infiltrating cytotoxic T lymphocytes (CD8+) in locally advanced rectal carcinomas after neoadjuvant treatment. Expression of IDO1 and CD8 was evaluated by immunohistochemistry in 106 archival tumour tissue samples from patients following neoadjuvant chemoradiation and radical resection. The average infiltration of IDO1+ and CD8+ cells was calculated along the tumour invasive front, in the tumour centre and within the neoplastic cells and expressed as total scores. Of the tumour specimens evaluable for immunohistochemistry, 100% showed CD8+ lymphocyte infiltration and 93.4% stained positive for IDO1. Total IDO1 score positively correlated with total CD8 score for all three subsites (p = 0.002, Kendall-tau-b 0.357). A high total CD8 score was positively correlated with lower ypUICC-stages (p = 0.047) and lower ypT-categories (p = 0.032). Total IDO1 expression showed a clear trend towards a lower risk of recurrence (p = 0.078). A high total IDO1 score was an independent prognostic marker for prolonged disease-free survival (HR 0.38, p = 0.046) and a high total CD8 score for favourable overall survival (HR 0.16, p = 0.029). Analysis of the local CD8 and IDO1 expression profile may be a helpful tool in predicting prognosis for patients with locally advanced rectal cancer following neoadjuvant chemoradiation.

[Evidence-based surgery of rectal cancer]

Over the past four decades, the treatment algorithms for rectal cancer have fundamentally changed, which resulted in a considerable improvement of oncological outcomes. In this context, the surgical concept of total mesorectal excision and the implementation of multimodal treatment strategies represent key milestones. These improvements were complemented by a standardized histopathological work-up of the surgical specimen and the introduction of high-resolution magnetic resonance imaging (MRI) diagnostics. In addition, novel surgical techniques have been introduced, such as laparoscopic and robotic rectal resection. Other technological innovations include intraoperative pelvic neuromonitoring and fluorescence imaging. This review highlights the current evidence for selected, sometimes controversially discussed principles of surgical treatment strategies in rectal cancer.

An overview of 25 years of incidence, treatment and outcome of colorectal cancer patients

Regarding the continuous changes in the diagnostic process and treatment of colorectal cancer (CRC), it is important to evaluate long-term trends which are relevant in giving direction for further research and innovations in cancer patient care. The aim of this study was to analyze developments in incidence, treatment and survival for patients diagnosed with CRC in the Netherlands. For this population-based retrospective cohort study, all patients diagnosed with CRC between 1989 and 2014 in the Netherlands were identified using data of the nationwide population-based Netherlands Cancer Registry (n = 267,765), with follow-up until January 1, 2016. Analyses were performed for trends in incidence, mortality, stage distribution, treatment and relative survival measured from the time of diagnosis. The incidence of both colon and rectal cancer has risen. The use of postoperative chemotherapy for Stage III colon cancer increased (14-60%), as well as the use of preoperative (chemo)radiotherapy for rectal cancer (2-66%). The administration of systemic therapy and metastasectomy increased for Stage IV disease patients. The 5-year relative survival increased significantly from 53 to 62% for colon cancer and from 51 to 65% for rectal cancer. Ongoing advancements in treatment, and also improvement in other factors in the care of CRC patients-such as diagnostics, dedicated surgery and pre- and postoperative care-lead to a continuous improvement in the relative survival of CRC patients. The increasing incidence of CRC favors the implementation of the screening program, of which the effects should be monitored closely.

Non-operative management of rectal cancer: understanding tumor biology

The management of locally-advanced rectal cancer involves a combination of chemotherapy, chemoradiation, and surgical resection to provide excellent local tumor control and overall survival. However, aspects of this multimodality approach are associated with significant morbidity and long-term sequelae. In addition, there is growing evidence that patients with a clinical complete response to chemotherapy and chemoradiation treatments may be safely offered initial non-operative management in a rigorous surveillance program. Weighed against the morbidity and significant sequelae of rectal resection, recognizing how to best optimize non-operative strategies without compromising oncologic outcomes is critical to our understanding and treatment of this disease.

Novelties in treatment of locally advanced rectal cancer

Treatment of locally advanced rectal cancer is evolving through surgical innovation and paradigm shifts in neoadjuvant treatment. Whereas local recurrence was a significant concern before the systematic implementation of neoadjuvant chemoradiation therapy and surgery according to total mesorectal excision principles, distant relapse remains a major drawback. Hence, efforts in recent years have focused on delivering preoperative chemotherapy regimens to overcome compliance issues with adjuvant administration. In parallel, new surgical techniques, including transanal video-assisted total mesorectal excision and robot-assisted surgery, emerged to face the challenge to navigate in the deep and narrow spaces of the pelvis. Furthermore, patients experiencing a complete response after neoadjuvant treatment might even escape surgery within a close surveillance strategy. This novel "watch and wait" concept has gained interest to improve quality of life in highly selected patients. This review summarizes recent evidence and controversies and provides an overview on timely and innovative aspects in the treatment of locally advanced rectal cancer.

Total neoadjuvant treatment (CAPOX plus radiotherapy) for patients with locally advanced rectal cancer with high risk factors: A phase 2 trial

BACKGROUND AND PURPOSE

To evaluate the safety and efficacy of Total neoadjuvant treatment (TNT) in patients with rectal cancer with high risk factors.

METHODS AND MATERIALS

We did this phase 2 trial in patients who were diagnosed with stage II-III rectal cancer with at least one of the high risk factors. Three cycles of induction CAPOX were followed by pelvic radiotherapy of 50.4 Gy/28 fractions and two cycles of concurrent CAPOX. Three cycles of consolidation CAPOX were delivered after radiotherapy. Primary endpoints were pathological complete response (pCR) and R0 resection.

RESULTS

Fifty patients were enrolled and 47 patients were evaluable. A total of 34 patients (72.3%) completed 6 to 8 cycles of chemotherapy and 46 patients (98%) completed the planned radiotherapy. 17 patients (36%) achieved a pCR or clinical complete response (cCR). Three cCR patients (6.4%) refused the operation and selected a watch-and-wait approach. The most common grade 3 or worse adverse events were leucopenia (10.6%) and radiation dermatitis (6.4%). The major surgical complications included pelvic abscesses/infection in 2 patients (4.3%), anastomotic leakage and hemorrhage in1 patient (2.2%), respectively, which were all addressed with conservative management.

CONCLUSIONS

TNT is effective and safe in patients with locally advanced rectal cancer with high risk factors. Long-term efficacies of TNT need to be further evaluated. This trial is registered with Chinese Clinical Trial Registry, number ChiCTR-OIN-17012284.

Early ambulation after colorectal oncologic resection with perineal reconstruction is safe and effective

BACKGROUND

Post-operative bedrest is common following perineal reconstruction despite little supporting data. We sought to determine the safety of early ambulation following colorectal oncologic resection and flap-based perineal reconstruction.

METHODS

A retrospective cohort study was conducted with two cohorts: standard bedrest (BC) and early ambulation (EAC). Ambulation capacity was objectively assessed. Regression analysis was performed to determine the effects of ambulation timing on 60-day reoperations or readmissions and other surgical outcomes.

RESULTS

There were 57 participants. Those in the EAC were significantly more ambulatory on post-operative days one through three (p < 0.0001). There was no significant difference in 60-day reoperations (25% BC versus 9% EAC, p = 0.14) or readmissions (33% BC versus 15% EAC, p = 0.12). Early ambulation significantly reduced minor complication rates (38% BC versus 9% EAC, p = 0.02).

CONCLUSIONS

Early ambulation following perineal reconstruction is safe and may potentially decrease wound complications.

SUMMARY AND KEYWORDS

Institution of early ambulation protocols is rapidly becoming the standard of care for many oncological surgery patients. In cases requiring perineal reconstruction with vascularized flaps, however, there is no data to uproot the historical practice of mandatory bedrest. Our study demonstrates that the benefits of early ambulation are attainable in these patients without compromising reconstructive outcomes.

Association of Plane of Total Mesorectal Excision With Prognosis of Rectal Cancer: Secondary Analysis of the CAO/ARO/AIO-04 Phase 3 Randomized Clinical Trial

Importance

Previous retrospective studies have shown that surgical quality affects local control in rectal cancer..

Objective

In this secondary end point analysis, we evaluated the prognostic effect of the total mesorectal excision (TME) plane in the CAO/ARO/AIO-04 phase 3 randomized clinical trial.

Design, Setting, and Participants

The CAO/ARO/AIO-04 trial enrolled 1236 patients with cT3-4 and/or node-positive rectal adenocarcinoma from 88 centers in Germany between July 25, 2006, and February 26, 2010.

Interventions

Patients were randomized to receive treatment with standard fluorouracil-based preoperative chemoradiotherapy (CRT) alone (control arm) or oxaliplatin (experimental arm) followed by TME and adjuvant chemotherapy.

Main Outcomes and Measures

The TME quality (mesorectal, intramesorectal, and muscularis propria plane) was prospectively assessed in 1152 operation specimens. An assessment was performed independently by pathologists and surgeons. The results were correlated with clinicopathologic data and the clinical outcome was tested, including multivariable analysis with the Cox regression model.

Results

Of 1152 German Caucasian participants, 332 (28.8) were women and the mean age was 63 years. The plane of TME was mesorectal in 930 patients (80.7%), intramesorectal in 169 (14.7%), and muscularis propria in 53 (4.6%). In a univariable analysis, the TME plane was significantly associated with 3-year disease-free survival (mesorectal vs intramesorectal vs muscularis propria, 95% CI, 73.1-78.8 vs 61.6-76.0 vs 55.6-81.3, respectively; P = .01), cumulative incidence of local and distant recurrences (mesorectal vs intramesorectal vs muscularis propria, 95% CI, 2.0-4.5 vs 1.2-8.1 vs 2.5-20.5, respectively; P < .001; and mesorectal vs intramesorectal vs muscularis propria, 95% CI, 17.0-22.4 vs 18.3-32.0 vs 14.2-39.0, respectively; P = .03, respectively), and overall survival (mesorectal vs intramesorectal vs muscularis propria, 95% CI, 88.3-92.3 vs 79.7-91.0 vs 81.6-98.7, respectively; P = .02). In contrast to the pathologist-based evaluation, the assessment of TME plane by the operating surgeon failed to demonstrate prognostic significance for any of these clinical end points. In a multivariable analysis, the plane of surgery (mesorectal vs muscularis propria TME) constituted an independent factor for local recurrence (P = .002).

Conclusions and Relevance

This phase 3 randomized clinical trial confirms the long-term clinical effect of TME plane quality on local recurrence, as initially reported in the MRC CR07 study. The data highlight the key role of pathologists and surgeons in the multidisciplinary management of rectal cancer.

Trial Registration

ClinicalTrials.gov Identifier: NCT00349076.