An International Expert-Based Consensus on the Definition of a Clinical Near-Complete Response After Neoadjuvant (Chemo)radiotherapy for Rectal Cancer

BACKGROUND

A variety of definitions for a clinical near-complete response after neoadjuvant (chemo) radiotherapy for rectal cancer are currently used. This variety leads to inconsistency in clinical practice, long-term outcome, and trial enrollment.

OBJECTIVE

The aim of this study was to reach expert-based consensus on the definition of a clinical near-complete response after (chemo) radiotherapy.

DESIGN

A modified Delphi process, including a systematic review, 3 surveys, and 2 meetings, was performed with an international expert panel consisting of 7 surgeons and 4 radiologists. The surveys consisted of individual features, statements, and feature combinations (endoscopy, T2-weighted MRI, and diffusion-weighted MRI).

SETTING

The modified Delphi process was performed in an online setting; all 3 surveys were completed online by the expert panel, and both meetings were hosted online.

MAIN OUTCOME MEASURES

The main outcome was to reach consensus (80% or more agreement).

RESULTS

The expert panel reached consensus on a 3-tier categorization of the near-complete response category based on the likelihood of the response to evolve into a clinical complete response after a longer waiting interval. The panelists agreed that a near-complete response is a temporary entity only to be used in the first 6 months after (chemo)radiotherapy. Furthermore, consensus was reached that the lymph node status should be considered when deciding on a near-complete response and that biopsies are not always needed when a near-complete response is found. No consensus was reached on whether primary staging characteristics have to be taken into account when deciding on a near-complete response.

LIMITATIONS

This 3-tier subcategorization is expert-based; therefore, there is no supporting evidence for this subcategorization. Also, it is unclear whether this subcategorization can be generalized into clinical practice.

CONCLUSIONS

Consensus was reached on the use of a 3-tier categorization of a near-complete response, which can be helpful in daily practice as guidance for treatment and to inform patients with a near-complete response on the likelihood of successful organ preservation. See Video Abstract.

UN CONSENSO INTERNACIONAL BASADO EN EXPERTOS ACERCA DE LA DEFINICIN DE UNA RESPUESTA CLNICA CASI COMPLETA DESPUS DE QUIMIORADIOTERAPIA NEOADYUVANTE CONTRA EL CNCER DE RECTO

ANTECEDENTES:Actualmente, se utilizan una variedad de definiciones para una respuesta clínica casi completa después de quimioradioterapia neoadyuvante contra el cáncer de recto. Esta variedad resulta en inconsistencia en la práctica clínica, los resultados a largo plazo y la inscripción en ensayos.OBJETIVO:El objetivo de este estudio fue llegar a un consenso de expertos sobre la definición de una respuesta clínica casi completa después de quimioradioterapia.DISEÑO:Se realizó un proceso Delphi modificado que incluyó una revisión sistemática, 3 encuestas y 2 reuniones con un panel internacional de expertos compuesto por siete cirujanos y 4 radiólogos. Las encuestas consistieron en características individuales, declaraciones y combinaciones de características (endoscopía, T2W-MRI y DWI).AJUSTE:El proceso Delphi modificado se realizó en un entorno en línea; el panel de expertos completó las tres encuestas en línea y ambas reuniones se realizaron en línea.PRINCIPALES MEDIDAS DE RESULTADO:El resultado principal fue llegar a un consenso (≥80% de acuerdo).RESULTADOS:El panel de expertos llegó a un consenso sobre una categorización de tres niveles de la categoría de respuesta casi completa basada en la probabilidad de que la respuesta evolucione hacia una respuesta clínica completa después de un intervalo de espera más largo. Los panelistas coincidieron en que una respuesta casi completa es una entidad temporal que sólo debe utilizarse en los primeros 6 meses después de la quimioradioterapia. Además, se llegó a un consenso en que se debe considerar el estado de los nódulos linfáticos al decidir sobre una respuesta casi completa y que no siempre se necesitan biopsias cuando se encuentra una respuesta casi completa. No se llegó a un consenso sobre si se deben tener en cuenta las características primarias de estadificación al decidir una respuesta casi completa.LIMITACIONES:Esta subcategorización de 3 niveles está basada en expertos; por lo tanto, no hay evidencia que respalde esta subcategorización. Además, no está claro si esta subcategorización puede generalizarse a la práctica clínica.CONCLUSIONES:Se alcanzó consenso sobre el uso de una categorización de 3 niveles de una respuesta casi completa que puede ser útil en la práctica diaria como guía para el tratamiento y para informar a los pacientes con una respuesta casi completa sobre la probabilidad de una preservación exitosa del órgano. (Traducción - Dr. Aurian Garcia Gonzalez).

Long-term restoration of bowel continuity after rectal cancer resection and the influence of surgical technique: A nationwide cross-sectional study

AIM

Literature on nationwide long-term permanent stoma rates after rectal cancer resection in the minimally invasive era is scarce. The aim of this population-based study was to provide more insight into the permanent stoma rate with interhospital variability (IHV) depending on surgical technique, with pelvic sepsis, unplanned reinterventions and readmissions as secondary outcomes.

METHOD

Patients who underwent open or minimally invasive resection of rectal cancer (lower border below the sigmoid take-off) in 67 Dutch centres in 2016 were included in this cross-sectional cohort study.

RESULTS

Among 2530 patients, 1470 underwent a restorative resection (58%), 356 a Hartmann's procedure (14%, IHV 0%-42%) and 704 an abdominoperineal resection (28%, IHV 3%-60%). Median follow-up was 51 months. The overall permanent stoma rate at last follow-up was 50% (IHV 13%-79%) and the unintentional permanent stoma rate, permanent stoma after a restorative procedure or an unplanned Hartmann's procedure, was 11% (IHV 0%-29%). A total of 2165 patients (86%) underwent a minimally invasive resection: 1760 conventional (81%), 170 transanal (8%) and 235 robot-assisted (11%). An anastomosis was created in 59%, 80% and 66%, with corresponding unintentional permanent stoma rates of 12%, 24% and 14% (p = 0.001), respectively. When corrected for age, American Society of Anesthesiologists classification, cTNM, distance to the anorectal junction and neoadjuvant (chemo)radiotherapy, the minimally invasive technique was not associated with an unintended permanent stoma (p = 0.071) after a restorative procedure.

CONCLUSION

A remarkable IHV in the permanent stoma rate after rectal cancer resection was found. No beneficial influence of transanal or robot-assisted laparoscopy on the unintentional permanent stoma rate was found, although this might be caused by the surgical learning curve. A reduction in IHV and improving preoperative counselling for decision-making for restorative procedures are required.

Evolution of clinical nature, treatment and survival of locally recurrent rectal cancer: Comparative analysis of two national cross-sectional cohorts

BACKGROUND

In the Netherlands, use of neoadjuvant radiotherapy for rectal cancer declined after guideline revision in 2014. This decline is thought to affect the clinical nature and treatability of locally recurrent rectal cancer (LRRC). Therefore, this study compared two national cross-sectional cohorts before and after the guideline revision with the aim to determine the changes in treatment and survival of LRRC patients over time.

METHODS

Patients who underwent resection of primary rectal cancer in 2011 (n = 2094) and 2016 (n = 2855) from two nationwide cohorts with a 4-year follow up were included. Main outcomes included time to LRRC, synchronous metastases at time of LRRC diagnosis, intention of treatment and 2-year overall survival after LRRC.

RESULTS

Use of neoadjuvant (chemo)radiotherapy for the primary tumour decreased from 88.5% to 60.0% from 2011 to 2016. The 3-year LRRC rate was not significantly different with 5.1% in 2011 (n = 114, median time to LRRC 16 months) and 6.3% in 2016 (n = 202, median time to LRRC 16 months). Synchronous metastasis rate did not significantly differ (27.2% vs 33.7%, p = 0.257). Treatment intent of the LRRC shifted towards more curative treatment (30.4% vs. 47.0%, p = 0.009). In the curatively treated group, two-year overall survival after LRRC diagnoses increased from 47.5% to 78.7% (p = 0.013).

CONCLUSION

Primary rectal cancer patients in 2016 were treated less often with neoadjuvant (chemo)radiotherapy, while LRRC rates remained similar. Those who developed LRRC were more often candidate for curative intent treatment compared to the 2011 cohort, and survival after curative intent treatment also improved substantially.

Seroma formation after mastectomy: A systematic review and network meta-analysis of different flap fixation techniques

Flap fixation is the most promising solution to prevent seroma formation after mastectomy. In this systematic review with network meta-analysis (NMA), three different techniques were compared. The NMA included 25 articles, comprising 3423 patients, and revealed that sutures are superior to tissue glue in preventing clinically significant seroma. In addition, running sutures seemed to be superior to interrupted sutures. An RCT comparing these suture techniques seems necessary, given the quality and nature of existing literature.

Association of Lateral Pelvic Lymph Nodes with Disease Recurrence and Organ Preservation in Patients with Distal Rectal Adenocarcinoma Treated with Total Neoadjuvant Therapy

OBJECTIVE

Assess the significance of enlarged lateral lymph nodes (LLN) for disease recurrence, metastasis, and organ preservation in patients with rectal cancer.

BACKGROUND

Optimal treatment of rectal adenocarcinoma involving LLN is subject to debate.

METHODS

A post hoc analysis of the OPRA trial, a multicenter study of patients with rectal cancer treated with total neoadjuvant therapy (TNT) followed by total mesorectal excision or watch-and-wait management. We analyzed the association of visible LLN (LLN+), LLN≥7 mm (short axis) on baseline MRI, and LLN≥4 mm on restaging MRI with recurrence, metastasis, and rectum preservation.

RESULTS

At baseline, 57 out of 324 (18%) patients had LLN+. In 30 (53%) of 57 patients with LLN+ on baseline MRI, the LLN disappeared after TNT. Disease recurrence in LLN was rare (3.5% of patients with LLN+ and 0.4% of patients with LLN-). All patients with recurrence in LLN also had distant metastasis. The rate of organ preservation was significantly lower in patients with LLN≥4 mm on restaging MRI (P=0.013). We found no significant differences in rates of local recurrence or metastasis between patients with LLN+ vs. LLN- and in patients with LLN≥7 vs.<7 mm on baseline MRI. LLN dissection was performed in 3 patients; 2 of them died of distant metastasis.

CONCLUSIONS

LLN involvement is not associated with disease recurrence or metastasis, but persistence of LLN≥4 mm after TNT is negatively associated with rectum preservation in patients with locally advanced rectal cancer treated with TNT. Dissection of lateral nodes likely benefits few patients.

Drain-free mastectomy and flap fixation: The interim analysis of a randomized controlled noninferiority trial

INTRODUCTION

Flap fixation after mastectomy has proven to be one of the most promising solutions to reduce seroma formation. Drain placement remains standard practice in many clinics, even though this may be redundant after flap fixation.

METHODS

This is a prospective randomized controlled trial comparing mastectomy and wound closure using flap fixation with or without drain placement. The primary outcome measure was clinically significant seroma (CSS) incidence. The aim of this interim analysis was to assess the assumptions for the sample size calculation and to provide preliminary results.

RESULTS

Between July 2020 and January 2023, 112 patients were included. CSS incidence was 9.1% in the drain group and 21% in the no-drain group. In total, 10 patients were lost to follow-up. These numbers are similar to the ones used for the sample size calculation. In the drain group, three patients required interventions for wound complications compared to nine in the no-drain group (odds ratio: 3.612 [95% confidence interval: 0.898-14.537]).

CONCLUSION

The sample size calculation seems to be correct and no protocol amendments are necessary. Current preliminary results show no significant differences in CSS incidence. Complete results should be awaited to draw a well-powered conclusion regarding drain policy after mastectomy.

The empty pelvis syndrome: a core data set from the PelvEx collaborative

BACKGROUND

Empty pelvis syndrome (EPS) is a significant source of morbidity following pelvic exenteration (PE), but is undefined. EPS outcome reporting and descriptors of radicality of PE are inconsistent; therefore, the best approaches for prevention are unknown. To facilitate future research into EPS, the aim of this study is to define a measurable core outcome set, core descriptor set and written definition for EPS. Consensus on strategies to mitigate EPS was also explored.

METHOD

Three-stage consensus methodology was used: longlisting with systematic review, healthcare professional event, patient engagement, and Delphi-piloting; shortlisting with two rounds of modified Delphi; and a confirmatory stage using a modified nominal group technique. This included a selection of measurement instruments, and iterative generation of a written EPS definition.

RESULTS

One hundred and three and 119 participants took part in the modified Delphi and consensus meetings, respectively. This encompassed international patient and healthcare professional representation with multidisciplinary input. Seventy statements were longlisted, seven core outcomes (bowel obstruction, enteroperineal fistula, chronic perineal sinus, infected pelvic collection, bowel obstruction, morbidity from reconstruction, re-intervention, and quality of life), and four core descriptors (magnitude of surgery, radiotherapy-induced damage, methods of reconstruction, and changes in volume of pelvic dead space) reached consensus-where applicable, measurement of these outcomes and descriptors was defined. A written definition for EPS was agreed.

CONCLUSIONS

EPS is an area of unmet research and clinical need. This study provides an agreed definition and core data set for EPS to facilitate further research.

Outcomes and potential impact of a virtual hands-on training program on MRI staging confidence and performance in rectal cancer

OBJECTIVES

To explore the potential impact of a dedicated virtual training course on MRI staging confidence and performance in rectal cancer.

METHODS

Forty-two radiologists completed a stepwise virtual training course on rectal cancer MRI staging composed of a pre-course (baseline) test with 7 test cases (5 staging, 2 restaging), a 1-day online workshop, 1 month of individual case readings (n = 70 cases with online feedback), a live online feedback session supervised by two expert faculty members, and a post-course test. The ESGAR structured reporting templates for (re)staging were used throughout the course. Results of the pre-course and post-course test were compared in terms of group interobserver agreement (Krippendorf's alpha), staging confidence (perceived staging difficulty), and diagnostic accuracy (using an expert reference standard).

RESULTS

Though results were largely not statistically significant, the majority of staging variables showed a mild increase in diagnostic accuracy after the course, ranging between + 2% and + 17%. A similar trend was observed for IOA which improved for nearly all variables when comparing the pre- and post-course. There was a significant decrease in the perceived difficulty level (p = 0.03), indicating an improved diagnostic confidence after completion of the course.

CONCLUSIONS

Though exploratory in nature, our study results suggest that use of a dedicated virtual training course and web platform has potential to enhance staging performance, confidence, and interobserver agreement to assess rectal cancer on MRI virtual training and could thus be a good alternative (or addition) to in-person training.

CLINICAL RELEVANCE STATEMENT

Rectal cancer MRI reporting quality is highly dependent on radiologists' expertise, stressing the need for dedicated training/teaching. This study shows promising results for a virtual web-based training program, which could be a good alternative (or addition) to in-person training.

KEY POINTS

• Rectal cancer MRI reporting quality is highly dependent on radiologists' expertise, stressing the need for dedicated training and teaching. • Using a dedicated virtual training course and web-based platform, encouraging first results were achieved to improve staging accuracy, diagnostic confidence, and interobserver agreement. • These exploratory results suggest that virtual training could thus be a good alternative (or addition) to in-person training.

Prevention of Seroma Formation and Its Sequelae After Axillary Lymph Node Dissection: An Up-to-Date Systematic Review and Guideline for Surgeons

INTRODUCTION

Seroma formation after axillary lymph node dissection (ALND) remains a troublesome complication with significant morbidity. Numerous studies have tried to identify techniques to prevent seroma formation. The aim of this systematic review and network meta-analysis is to use available literature to identify the best intervention for prevention of seroma after standalone ALND.

METHODS

A literature search was performed for all comparative articles regarding seroma formation in patients undergoing a standalone ALND or ALND with breast-conserving surgery in the last 25 years. Data regarding seroma formation, clinically significant seroma (CSS), surgical site infections (SSI), and hematomas were collected. The network meta-analysis was performed using a random effects model and the level of inconsistency was evaluated using the Bucher method.

RESULTS

A total of 19 articles with 1962 patients were included. Ten different techniques to prevent seroma formation were described. When combining direct and indirect comparisons, axillary drainage until output is less than 50 ml per 24 h for two consecutive days results in significantly less CSS. The use of energy sealing devices, padding, tissue glue, or patches did not significantly reduce the incidence of CSS. When comparing the different techniques with regard to SSIs, no statistically significant differences were seen.

CONCLUSIONS

To prevent CSS after ALND, axillary drainage is the most valuable and scientifically proven measure. On the basis of the results of this systematic review with network meta-analysis, removing the drain when output is < 50 ml per 24 h for two consecutive days irrespective of duration seems best. Since drainage policies vary widely, an evidence-based guideline is needed.

Whole-body MRI with diffusion-weighted imaging as an adjunct to18 F-fluorodeoxyglucose positron emission tomography and CT in patients with suspected recurrent colorectal cancer

AIM

The aim was to explore how findings of whole-body MRI including diffusion-weighted imaging (DW-MRI) compared to the routine diagnostic workup with CT and/or 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT in patients with suspected recurrent colorectal cancer (CRC).

METHOD

This was an exploratory retrospective analysis of 55 patients with a clinical suspicion of recurrent CRC who underwent DW-MRI following CT and/or FDG-PET/CT. Two readers in consensus interpreted all clinical imaging reports and converted each described lesion into a confidence score (1 = definitely benign to 5 = definitely malignant). DW-MRI findings were compared to the most recent previous CT or PET/CT. Any discrepant or additional DW-MRI findings were documented and compared with histology and/or clinical follow-up (if available).

RESULTS

Whole-body MRI including diffusion-weighted imaging (DW-MRI) resulted in discrepant/additional findings in 26/55 (47%) cases; 23/37 (62%) compared to previous CT and 3/18 (17%) compared to previous PET/CT. These included 10 cases where DW-MRI converted previously inconclusive CT (n = 8) or PET/CT (n = 2) findings into a conclusive diagnosis, one where it contradicted a previous CT diagnosis of recurrence, five where DW-MRI diagnosed recurrent disease not previously reported on CT and 10 cases where DW-MRI detected additional lesions compared to CT (n = 9) or PET/CT (n = 1). Eighty-eight per cent of cases with discrepant/additional findings concerned patients with recurrent/metachronous peritoneal metastases. In total, DW-MRI resulted in 42 discrepant/additional lesions; the DW-MRI diagnosis was correct in 76% of these lesions and incorrect (false positive) in 7%. In the remaining 17%, no standard of reference was available.

CONCLUSIONS

This explorative study suggests that DW-MRI may be of added value to patients with a clinical suspicion for recurrent CRC, in particular to identify patients with peritoneal metastases. DW-MRI mainly has potential as a 'problem-solver' in patients with inconclusive or negative findings on previous imaging (in particular CT) and to detect additional disease sites in patients already diagnosed with recurrent disease.

Abandonment of Routine Radiotherapy for Nonlocally Advanced Rectal Cancer and Oncological Outcomes

Importance

Neoadjuvant short-course radiotherapy was routinely applied for nonlocally advanced rectal cancer (cT1-3N0-1M0 with >1 mm distance to the mesorectal fascia) in the Netherlands following the Dutch total mesorectal excision trial. This policy has shifted toward selective application after guideline revision in 2014.

Objective

To determine the association of decreased use of neoadjuvant radiotherapy with cancer-related outcomes and overall survival at a national level.

Design, Setting, and Participants

This multicenter, population-based, nationwide cross-sectional cohort study analyzed Dutch patients with rectal cancer who were treated in 2011 with a 4-year follow-up. A similar study was performed in 2021, analyzing all patients that were surgically treated in 2016. From these cohorts, all patients with cT1-3N0-1M0 rectal cancer and radiologically unthreatened mesorectal fascia were included in the current study. The data of the 2011 cohort were collected between May and October 2015, and the data of the 2016 cohort were collected between October 2020 and November 2021. The data were analyzed between May and October 2022.

Main Outcomes and Measures

The main outcomes were 4-year local recurrence and overall survival rates.

Results

Among the 2011 and 2016 cohorts, 1199 (mean [SD] age, 68 [11] years; 430 women [36%]) of 2095 patients (57.2%) and 1576 (mean [SD] age, 68 [10] years; 547 women [35%]) of 3057 patients (51.6%) had cT1-3N0-1M0 rectal cancer and were included, with proportions of neoadjuvant radiotherapy of 87% (2011) and 37% (2016). Four-year local recurrence rates were 5.8% and 5.5%, respectively (P = .99). Compared with the 2011 cohort, 4-year overall survival was significantly higher in the 2016 cohort (79.6% vs 86.4%; P < .001), with lower non-cancer-related mortality (13.8% vs 6.3%; P < .001).

Conclusions and Relevance

The results of this cross-sectional study suggest that an absolute 50% reduction in radiotherapy use for nonlocally advanced rectal cancer did not compromise cancer-related outcomes at a national level. Optimizing clinical staging and surgery following the Dutch total mesorectal excision trial has potentially enabled safe deintensification of treatment.

An automated deep learning pipeline for EMVI classification and response prediction of rectal cancer using baseline MRI: a multi-centre study

The classification of extramural vascular invasion status using baseline magnetic resonance imaging in rectal cancer has gained significant attention as it is an important prognostic marker. Also, the accurate prediction of patients achieving complete response with primary staging MRI assists clinicians in determining subsequent treatment plans. Most studies utilised radiomics-based methods, requiring manually annotated segmentation and handcrafted features, which tend to generalise poorly. We retrospectively collected 509 patients from 9 centres, and proposed a fully automated pipeline for EMVI status classification and CR prediction with diffusion weighted imaging and T2-weighted imaging. We applied nnUNet, a self-configuring deep learning model, for tumour segmentation and employed learned multiple-level image features to train classification models, named MLNet. This ensures a more comprehensive representation of the tumour features, in terms of both fine-grained detail and global context. On external validation, MLNet, yielding similar AUCs as internal validation, outperformed 3D ResNet10, a deep neural network with ten layers designed for analysing spatiotemporal data, in both CR and EMVI tasks. For CR prediction, MLNet showed better results than the current state-of-the-art model using imaging and clinical features in the same external cohort. Our study demonstrated that incorporating multi-level image representations learned by a deep learning based tumour segmentation model on primary MRI improves the results of EMVI classification and CR prediction with good generalisation to external data. We observed variations in the contributions of individual feature maps to different classification tasks. This pipeline has the potential to be applied in clinical settings, particularly for EMVI classification.

Nonoperative management of the primary tumor in patients with unresectable stage IV colon cancer treated with systemic chemotherapy: Higher complication rates for left-sided colon tumors

INTRODUCTION

Treatment of the primary tumor in asymptomatic patients with unresectable colorectal metastases remains controversial.

METHODS

Data from patients with synchronous stage IV colon cancer and an untreated primary tumor who started treatment aimed at metastatic disease at a specialized cancer center between 2014 and 2018 were analyzed retrospectively. Main outcome was primary tumor-related complications comparing left-sided and right-sided colon cancer. A competing-risk regression model was used to identify predictors of complications.

RESULTS

Of 523 patients with metastatic colon cancer at presentation, 221 started treatment aimed at metastatic disease; these patients constituted the study cohort. The primary tumor was left-sided in 109 patients (49%) and right-sided in 112 patients (51%). In total, 46 patients (21%) developed a complication that required invasive intervention. Complications occurred more frequently in patients with left-sided tumors than in patients with right-sided tumors (29% vs 13%, P = 0.003). Eighteen patients (8%) underwent non-surgical intervention. Six patients (33%) failed non-surgical management and underwent surgery. Of 34 patients (15%) who underwent surgical intervention, 20 underwent an emergency colectomy and 14 underwent diversion with a permanent stoma. Overall, 10% of patients ended up with a permanent stoma. In competing-risk analysis, only left-sided primary tumor (hazard ratio 2.62; 95% CI 1.40-4.89; P = 0.003) was significantly associated with primary tumor-related complications requiring invasive intervention.

CONCLUSIONS

Patients with asymptomatic metastatic left-sided tumors have a higher risk for primary tumor-related complications than patients with right-sided tumors. Close monitoring and early surgical rescue should be considered for patients with left-sided colon cancer who are managed nonoperatively.

Optimisation of Organ Preservation treatment strategies in patients with rectal cancer with a good clinical response after neoadjuvant (chemo)radiotherapy: Additional contact X-ray brachytherapy versus eXtending the observation period and local excision (OPAXX) - protocol for two multicentre, parallel, single-arm, phase II studies

INTRODUCTION

Standard treatment for patients with intermediate or locally advanced rectal cancer is (chemo)radiotherapy followed by total mesorectal excision (TME) surgery. In recent years, organ preservation aiming at improving quality of life has been explored. Patients with a complete clinical response to (chemo)radiotherapy can be managed safely with a watch-and-wait approach. However, the optimal organ-preserving treatment strategy for patients with a good, but not complete clinical response remains unclear. The aim of the OPAXX study is to determine the rate of organ preservation that can be achieved in patients with rectal cancer with a good clinical response after neoadjuvant (chemo)radiotherapy by additional local treatment options.

METHODS AND ANALYSIS

The OPAXX study is a Dutch multicentre study that investigates the efficacy of two additional local treatments aiming at organ preservation in patients with a good, but not complete response to neoadjuvant treatment (ie near-complete response or a small residual tumour mass <3 cm). The sample size will be 168 patients in total. Patients will be randomised (1:1) between two parallel single-arm phase II studies: study arm 1 involves additional contact X-ray brachytherapy (an intraluminal radiation boost), while in study arm 2 the observation period is extended followed by a second response evaluation and optional transanal local excision. The primary endpoint of the study is the rate of successful organ preservation at 1 year following randomisation. Secondary endpoints include toxicity, morbidity, oncological and functional outcomes at 1 and 2 years of follow-up. Finally, an observational cohort study for patients who are not eligible for randomisation is conducted.

ETHICS AND DISSEMINATION

The trial protocol has been approved by the medical ethics committee of the Netherlands Cancer Institute (METC20.1276/M20PAX). Informed consent will be obtained from all participants. The trial results will be published in an international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT05772923.

The Role of Nonmetastatic Lymph Nodes in the Survival of Colorectal Cancer: A Systematic Review

Objective

In this review, we aim to provide an overview of literature on lymph node (LN) histomorphological features and their relationship with the prognosis in colorectal cancer (CRC).

Background

Lymph nodes play a crucial role in the treatment and prognosis of CRC. The presence of LN metastases considerably worsens the prognosis in CRC patients. Literature has shown that the total number of LNs and the number negative LNs (LNnegs) has prognostic value in CRC patients. In esophageal carcinoma, LN size seems to be surrogate of the host antitumor response and a potentially clinically useful new prognostic biomarker for (y)pN0 esophageal carcinoma.

Methods

A comprehensive search was performed in Pubmed, Embase, Medline, CINAHL, and the Cochrane library in March 2021. The PRISMA guidelines were followed. Only studies focusing on histomorphological features and LN size and their relation to overall survival were selected.

Results

A total of 9 unique articles met all inclusion criteria and were therefore included in this systematic review. Six of these studies investigated HMF (eg, paracortical hyperplasia, germinal center predominance, and sinus histiocytosis) and 4 studies LNneg size and their relationship with overall survival. The presence of paracortical hyperplasia and an increased number of large LNnegs is related to a more favorable prognosis in CRC.

Conclusion

The results of this systematic review seem to support the hypothesis that there is a relationship between the host antitumor response reflected in different histomorphological reaction patterns visible in LNnegs and LNneg size related to survival in CRC patients.

Development and multicenter validation of a multiparametric imaging model to predict treatment response in rectal cancer

OBJECTIVES

To develop and validate a multiparametric model to predict neoadjuvant treatment response in rectal cancer at baseline using a heterogeneous multicenter MRI dataset.

METHODS

Baseline staging MRIs (T2W (T2-weighted)-MRI, diffusion-weighted imaging (DWI) / apparent diffusion coefficient (ADC)) of 509 patients (9 centres) treated with neoadjuvant chemoradiotherapy (CRT) were collected. Response was defined as (1) complete versus incomplete response, or (2) good (Mandard tumor regression grade (TRG) 1-2) versus poor response (TRG3-5). Prediction models were developed using combinations of the following variable groups: (1) Non-imaging: age/sex/tumor-location/tumor-morphology/CRT-surgery interval (2) Basic staging: cT-stage/cN-stage/mesorectal fascia involvement, derived from (2a) original staging reports, or (2b) expert re-evaluation (3) Advanced staging: variables from 2b combined with cTN-substaging/invasion depth/extramural vascular invasion/tumor length (4) Quantitative imaging: tumour volume + first-order histogram features (from T2W-MRI and DWI/ADC) Models were developed with data from 6 centers (n = 412) using logistic regression with the Least Absolute Shrinkage and Selector Operator (LASSO) feature selection, internally validated using repeated (n = 100) random hold-out validation, and externally validated using data from 3 centers (n = 97).

RESULTS

After external validation, the best model (including non-imaging and advanced staging variables) achieved an area under the curve of 0.60 (95%CI=0.48-0.72) to predict complete response and 0.65 (95%CI=0.53-0.76) to predict a good response. Quantitative variables did not improve model performance. Basic staging variables consistently achieved lower performance compared to advanced staging variables.

CONCLUSIONS

Overall model performance was moderate. Best results were obtained using advanced staging variables, highlighting the importance of good-quality staging according to current guidelines. Quantitative imaging features had no added value (in this heterogeneous dataset).

CLINICAL RELEVANCE STATEMENT

Predicting tumour response at baseline could aid in tailoring neoadjuvant therapies for rectal cancer. This study shows that image-based prediction models are promising, though are negatively affected by variations in staging quality and MRI acquisition, urging the need for harmonization.

KEY POINTS

This multicenter study combining clinical information and features derived from MRI rendered disappointing performance to predict response to neoadjuvant treatment in rectal cancer. Best results were obtained with the combination of clinical baseline information and state-of-the-art image-based staging variables, highlighting the importance of good quality staging according to current guidelines and staging templates. No added value was found for quantitative imaging features in this multicenter retrospective study. This is likely related to acquisition variations, which is a major problem for feature reproducibility and thus model generalizability.

Sense and non-sense of imaging in the era of organ preservation for rectal cancer

This review summarizes the current applications and benefits of imaging modalities for organ preservation in the treatment of rectal cancer. The concept of organ preservation in the treatment of rectal cancer has revolutionized the way rectal cancer is managed. Initially, organ preservation was limited to patients with locally advanced rectal cancer who needed neoadjuvant therapy to reduce tumor size before surgery and achieved complete response. However, neoadjuvant therapy is now increasingly utilized for smaller and less aggressive tumors to achieve primary organ preservation. Additionally, more intensive neoadjuvant strategies are employed to improve complete response rates and increase the chances of successful organ preservation. The selection of patients for organ preservation is a critical component of treatment, and imaging techniques such as digital rectal exam, endoscopy, and MRI are commonly used for this purpose. In this review, we provide an overview of what imaging modalities should be chosen and how they can aid in the selection and follow-up of patients undergoing organ-preserving strategies.

Pearls and pitfalls of structured staging and reporting of rectal cancer on MRI: an international multireader study

OBJECTIVES

To investigate uniformity and pitfalls in structured radiological staging of rectal cancer.

METHODS

Twenty-one radiologists (12 countries) staged 75 rectal cancers on MRI using a structured reporting template. Interobserver agreement (IOA) was calculated as the percentage agreement between readers (categorical variables) and Krippendorff's α (continuous variables). Agreement with an expert consensus served as a surrogate standard of reference to estimate diagnostic accuracy. Polychoric correlation coefficients were used to assess correlations between diagnostic confidence and accuracy (=agreement with expert consensus).

RESULTS

Uniformity to diagnose high-risk (≥cT3 ab) versus low-risk (≤cT3 cd) cT-stage, cN0 versus cN+, lateral nodes and tumour deposits, MRF and sphincter involvement, and solid versus mucinous tumours was high with IOA > 80% in the majority of cases (and >80% agreement with expert consensus). Results for assessing extramural vascular invasion, cT-stage (cT1-2/cT3/cT4a/cT4b), cN-stage (cN0/N1/N2), relation to the peritoneal reflection, extent of sphincter involvement (internal/intersphincteric/external) and morphology (solid/annular/semi-annular) were considerably poorer. IOA was high (α = 0.72-0.84) for tumour height/length and extramural invasion depth, but low for tumour-MRF distance and number of (suspicious) nodes (α = 0.05-0.55). There was a significant positive correlation between diagnostic confidence and accuracy (=agreement with expert consensus) (p < 0.001-p = 0.003).

CONCLUSIONS

- Several staging items lacked sufficient reproducibility.- Results for cT- and N-staging g improved when using a dichotomized stratification.- Considering the significant correlation between diagnostic confidence and accuracy, a confidence level may be incorporated into structured reporting for specific items with low reproducibility.

ADVANCES IN KNOWLEDGE

Although structured reporting aims to achieve uniformity in reporting, several items lack sufficient reproducibility and might benefit from dichotomized assessment and incorporating confidence levels.

Predicting response to chemoradiotherapy in rectal cancer via visual morphologic assessment and staging on baseline MRI: a multicenter and multireader study

PURPOSE

Pre-treatment knowledge of the anticipated response of rectal tumors to neoadjuvant chemoradiotherapy (CRT) could help to further optimize the treatment. Van Griethuysen et al. proposed a visual 5-point confidence score to predict the likelihood of response on baseline MRI. Aim was to evaluate this score in a multicenter and multireader study setting and compare it to two simplified (4-point and 2-point) adaptations in terms of diagnostic performance, interobserver agreement (IOA), and reader preference.

METHODS

Twenty-two radiologists from 14 countries (5 MRI-experts,17 general/abdominal radiologists) retrospectively reviewed 90 baseline MRIs to estimate if patients would likely achieve a (near-)complete response (nCR); first using the 5-point score by van Griethuysen (1=highly unlikely to 5=highly likely to achieve nCR), second using a 4-point adaptation (with 1-point each for high-risk T-stage, obvious mesorectal fascia invasion, nodal involvement, and extramural vascular invasion), and third using a 2-point score (unlikely/likely to achieve nCR). Diagnostic performance was calculated using ROC curves and IOA using Krippendorf's alpha (α).

RESULTS

Areas under the ROC curve to predict the likelihood of a nCR were similar for the three methods (0.71-0.74). IOA was higher for the 5- and 4-point scores (α=0.55 and 0.57 versus 0.46 for the 2-point score) with best results for the MRI-experts (α=0.64-0.65). Most readers (55%) favored the 4-point score.

CONCLUSIONS

Visual morphologic assessment and staging methods can predict neoadjuvant treatment response with moderate-good performance. Compared to a previously published confidence-based scoring system, study readers preferred a simplified 4-point risk score based on high-risk T-stage, MRF involvement, nodal involvement, and EMVI.

A Deep Learning Framework with Explainability for the Prediction of Lateral Locoregional Recurrences in Rectal Cancer Patients with Suspicious Lateral Lymph Nodes

Malignant lateral lymph nodes (LLNs) in low, locally advanced rectal cancer can cause (ipsi-lateral) local recurrences ((L)LR). Accurate identification is, therefore, essential. This study explored LLN features to create an artificial intelligence prediction model, estimating the risk of (L)LR. This retrospective multicentre cohort study examined 196 patients diagnosed with rectal cancer between 2008 and 2020 from three tertiary centres in the Netherlands. Primary and restaging T2W magnetic resonance imaging and clinical features were used. Visible LLNs were segmented and used for a multi-channel convolutional neural network. A deep learning model was developed and trained for the prediction of (L)LR according to malignant LLNs. Combined imaging and clinical features resulted in AUCs of 0.78 and 0.80 for LR and LLR, respectively. The sensitivity and specificity were 85.7% and 67.6%, respectively. Class activation map explainability methods were applied and consistently identified the same high-risk regions with structural similarity indices ranging from 0.772-0.930. This model resulted in good predictive value for (L)LR rates and can form the basis of future auto-segmentation programs to assist in the identification of high-risk patients and the development of risk stratification models.

Size and depth of residual tumor after neoadjuvant chemoradiotherapy in rectal cancer - implications for the development of new imaging modalities for response assessment

With the shift towards organ preserving treatment strategies in rectal cancer it has become increasingly important to accurately discriminate between a complete and good clinical response after neoadjuvant chemoradiotherapy (CRT). Standard of care imaging techniques such as CT and MRI are well equipped for initial staging of rectal tumors, but discrimination between a good clinical and complete response remains difficult due to their limited ability to detect small residual vital tumor fragments. To identify new promising imaging techniques that could fill this gap, it is crucial to know the size and invasion depth of residual vital tumor tissue since this determines the requirements with regard to the resolution and imaging depth of potential new optical imaging techniques. We analyzed 198 pathology slides from 30 rectal cancer patients with a Mandard tumor regression grade 2 or 3 after CRT that underwent surgery. For each patient we determined response pattern, size of the largest vital tumor fragment or bulk and the shortest distance from the vital tumor to the luminal surface. The response pattern was shrinkage in 14 patients and fragmentation in 16 patients. For both groups combined, the largest vital tumor fragment per patient was smaller than 1mm for 38% of patients, below 0.2mm for 12% of patients and for one patient as small as 0.06mm. For 29% of patients the vital tumor remnant was present within the first 0.01mm from the luminal surface and for 87% within 0.5mm. Our results explain why it is difficult to differentiate between a good clinical and complete response in rectal cancer patients using endoscopy and MRI, since in many patients submillimeter tumor fragments remain below the luminal surface. To detect residual vital tumor tissue in all patients included in this study a technique with a spatial resolution of 0.06mm and an imaging depth of 8.9mm would have been required. Optical imaging techniques offer the possibility of detecting majority of these cases due to the potential of both high-resolution imaging and enhanced contrast between tissue types. These techniques could thus serve as a complimentary tool to conventional methods for rectal cancer response assessment.

Sense and nonsense of yT-staging on MRI after chemoradiotherapy in rectal cancer

AIM

The aim of this work was to investigate the value of rectal cancer T-staging on MRI after chemoradiotherapy (ymrT-staging) in relation to the degree of fibrotic transformation of the tumour bed as assessed using the pathological tumour regression grade (pTRG) of Mandard as a standard of reference.

METHOD

Twenty two radiologists, including five rectal MRI experts and 17 'nonexperts' (general/abdominal radiologists), evaluated the ymrT stage on the restaging MRIs of 90 rectal cancer patients after chemoradiotherapy. The ymrT stage was compared with the final ypT stage at histopathology; the percentages of correct staging (ymrT = ypT), understaging (ymrT < ypT) and overstaging (ymrT > ypT) were calculated and compared between patients with predominant tumour at histopathology (pTRG4-5) and patients with predominant fibrosis (pTRG1-3). Interobserver agreement (IOA) was computed using Krippendorff's alpha.

RESULTS

Average ymrT/ypT stage concordance was 48% for the experts and 43% for the nonexperts; ymrT/ypT stage concordance was significantly higher in the pTRG4-5 subgroup (58% vs. 41% for the pTRG1-3 group; p = 0.01), with the best results for the MRI experts. Overstaging was the main source of error, especially in the pTRG1-3 subgroup (average overstaging rate 38%-44% vs. 13%-55% in the pTRG4-5 subgroup). IOA was higher for the expert versus nonexpert readers (α = 0.67 vs. α = 0.39).

CONCLUSIONS

ymrT-staging is moderately accurate; accuracy is higher in poorly responding patients with predominant tumour but low in good responders with predominant fibrosis, resulting in significant overstaging. Radiologists should shift their focus from ymrT-staging to detecting gross residual (and progressive) disease, and identifying potential candidates for organ preservation who would benefit from further clinical and endoscopic evaluation to guide final treatment planning.

Economic evaluation of flap fixation techniques after mastectomy: Results of a double-blind randomized controlled trial (SAM-trial)

BACKGROUND

An economic evaluation was performed alongside an RCT investigating flap fixation in reducing seroma formation after mastectomy. The evaluation focused on the first year following mastectomy and assessed cost-effectiveness from a health care and societal perspective.

METHODS

The economic evaluation was conducted between 2014 and 2018 in four Dutch breast clinics. Patients with an indication for mastectomy or modified radical mastectomy were randomly assigned to: conventional closure (CON), flap fixation with sutures (FFS) or flap fixation with tissue glue (FFG). Health care costs, patient and family costs and costs due to productivity losses were assessed. Outcomes were expressed in incremental cost-effectiveness ratios (ICERs): the incremental cost per quality-adjusted life year (QALY). Bootstrapping techniques, sensitivity and secondary analyses were employed to address uncertainty.

RESULTS

The FFS-group yielded most QALYs (0.810; 95%-CI 0.755-0.856), but also incurred the highest mean costs at twelve months (€10.416; 95%-CI 8.231-12.930). CON was the next best alternative with 0.794 QALYs (95%-CI 0.733-0.841) and mean annual costs of €10.051 (95%-CI 8.255-12.044). FFG incurred fewer QALYs and higher costs, when compared to the CON group. The ICER of FFS compared to CON was €22.813/QALY. Applying a willingness to pay threshold in the Netherlands of €20.000/QALY, the probability that FFS was cost-effective was 42%, compared to 37% and 21% for CON and FFG, respectively.

CONCLUSION

The cost-effectiveness of FFS following mastectomy, versus CON and FFG, is uncertain from a societal perspective. Yet, from a health care and hospital perspective FFS is likely to be the most cost-effective intervention.

Evaluation of National Surgical Practice for Lateral Lymph Nodes in Rectal Cancer in an Untrained Setting

BACKGROUND

Involved lateral lymph nodes (LLNs) have been associated with increased local recurrence (LR) and ipsi-lateral LR (LLR) rates. However, consensus regarding the indication and type of surgical treatment for suspicious LLNs is lacking. This study evaluated the surgical treatment of LLNs in an untrained setting at a national level.

METHODS

Patients who underwent additional LLN surgery were selected from a national cross-sectional cohort study regarding patients undergoing rectal cancer surgery in 69 Dutch hospitals in 2016. LLN surgery consisted of either 'node-picking' (the removal of an individual LLN) or 'partial regional node dissection' (PRND; an incomplete resection of the LLN area). For all patients with primarily enlarged (≥7 mm) LLNs, those undergoing rectal surgery with an additional LLN procedure were compared to those  undergoing only rectal resection.

RESULTS

Out of 3057 patients, 64 underwent additional LLN surgery, with 4-year LR and LLR rates of 26% and 15%, respectively. Forty-eight patients (75%) had enlarged LLNs, with corresponding recurrence rates of 26% and 19%, respectively. Node-picking (n = 40) resulted in a 20% 4-year LLR, and a 14% LLR after PRND (n = 8; p = 0.677). Multivariable analysis of 158 patients with enlarged LLNs undergoing additional LLN surgery (n = 48) or rectal resection alone (n = 110) showed no significant association of LLN surgery with 4-year LR or LLR, but suggested higher recurrence risks after LLN surgery (LR: hazard ratio [HR] 1.5, 95% confidence interval [CI] 0.7-3.2, p = 0.264; LLR: HR 1.9, 95% CI 0.2-2.5, p = 0.874).

CONCLUSION

Evaluation of Dutch practice in 2016 revealed that approximately one-third of patients with primarily enlarged LLNs underwent surgical treatment, mostly consisting of node-picking. Recurrence rates were not significantly affected by LLN surgery, but did suggest worse outcomes. Outcomes of LLN surgery after adequate training requires further research.

Watch and wait after neoadjuvant treatment in rectal cancer: comparison of outcomes in patients with and without a complete response at first reassessment in the International Watch & Wait Database (IWWD)

BACKGROUND

In rectal cancer, watch and wait for patients with a cCR after neoadjuvant treatment has an established evidence base. However, there is a lack of consensus on the definition and management of a near-cCR. This study aimed to compare outcomes in patients who achieved a cCR at first reassessment versus later reassessment.

METHODS

This registry study included patients from the International Watch & Wait Database. Patients were categorized as having a cCR at first reassessment or at later reassessment (that is near-cCR at first reassessment) based on MRI and endoscopy. Organ preservation, distant metastasis-free survival, and overall survival rates were calculated. Subgroup analyses were done for near-cCR groups based on the response evaluation according to modality.

RESULTS

A total of 1010 patients were identified. At first reassessment, 608 patients had a cCR; 402 had a cCR at later reassessment. Median follow-up was 2.6 years for patients with a cCR at first reassessment and 2.9 years for those with a cCR at later reassessment. The 2-year organ preservation rate was 77.8 (95 per cent c.i. 74.2 to 81.5) and 79.3 (75.1 to 83.7) per cent respectively (P = 0.499). Similarly, no differences were found between groups in distant metastasis-free survival or overall survival rate. Subgroup analyses showed a higher organ preservation rate in the group with a near-cCR categorized exclusively by MRI.

CONCLUSION

Oncological outcomes for patients with a cCR at later reassessment are no worse than those of patients with a cCR at first reassessment.

Long-term Quality of Life and Functional Outcome of Patients With Rectal Cancer Following a Watch-and-Wait Approach

Importance

A watch-and-wait approach for patients with rectal cancer and a clinical complete response after neoadjuvant chemoradiotherapy or radiotherapy is associated with better quality of life and functional outcome. Nevertheless, prospective data on both parameters are scarce.

Objective

To prospectively evaluate quality of life and functional outcome, including bowel, urinary, and sexual function, of patients following a watch-and-wait approach.

Design, Setting, and Participants

A total of 278 patients with rectal cancer and a clinical complete response or near-complete response after neoadjuvant chemoradiotherapy or radiotherapy were included in 2 prospective cohort studies: a single-center study (March 2014 to October 2017) and an ongoing multicenter study (from September 2017). Patients were observed by a watch-and-wait approach. Additional local excision or total mesorectal excision was performed for residual disease or regrowth. Data were analyzed between April 1, 2021, and August 27, 2021, for patients with a minimum follow-up of 24 months.

Main Outcomes and Measures

Quality of life was evaluated with the European Organisation for Research and Treatment of Cancer-Quality of Life Questionnaire-C30 (EORTC-QLQ-C30), EORTC-QLQ-CR38, or EORTC-QLQ-CR29 and 36-Item Short-Form Health Survey. The score for the questionnaires and 36-Item Short-Form Health Survey ranges from 0 to 100. For some scales, a high score indicates a high level of functioning, and for others it indicates a high level of complaints and symptomatology. Functional outcome was assessed by the Low Anterior Resection Syndrome score, Vaizey incontinence score, International Prostate Symptom Score, International Index of Erectile Function, and Female Sexual Function Index.

Results

Of 278 patients included, 187 were male (67%), and the median age was 66 years (range, 34-85 years). In the first 24 months, 221 patients (80%) were observed by a watch-and-wait approach without requiring surgery, 18 patients (6%) underwent additional local excision, and 39 patients (14%) underwent total mesorectal excision. In general, patients observed by a watch-and-wait approach reported good quality of life, with limited variation over time. At 3 months, 56 of 221 patients (25.3%) reported major bowel dysfunction; at 12 months, 53 patients (24.0%) reported it; and at 24 months, 55 patients (24.9%) reported it. At 24 months, 48 of 151 male patients (31.8%) reported severe erectile dysfunction. For female patients, sexual satisfaction and overall sexual function decreased during follow-up. Patients who underwent local excision reported more major bowel dysfunction (10 of 18 patients [55.6%]) compared with those without additional surgery. Quality-of-life scores, however, were comparable. After total mesorectal excision, patients scored significantly worse on several quality-of-life subscales.

Conclusions and Relevance

Results of this study suggest that patients with rectal cancer who were observed by a watch-and-wait approach had good quality of life, with some patients reporting bowel and sexual dysfunction. Quality of life and functional outcome deteriorated when patients required surgery. These data will be useful in daily care to counsel patients on what to expect from a watch-and-wait approach.

Delayed TME Surgery in a Watch-and-Wait Strategy After Neoadjuvant Chemoradiotherapy for Rectal Cancer: An Analysis of Hospital Costs and Surgical and Oncological Outcomes

BACKGROUND

A watch-and-wait strategy for patients with rectal cancer with a clinical complete response after neoadjuvant chemoradiotherapy is a valuable alternative for rectal resection. However, there are patients who will have residual tumor or regrowth during watch and wait.

OBJECTIVE

The aim of this study was to investigate safety and costs for patients who underwent delayed surgery after neoadjuvant chemoradiotherapy.

DESIGN

This is a retrospective cohort study with prospectively collected data.

SETTINGS

The study was conducted at a large teaching hospital.

PATIENTS

Between January 2015 and May 2020, 622 new rectal cancer patients were seen, of whom 200 received neoadjuvant chemoradiotherapy. Ninety-four patients were included, 65 of whom underwent immediate surgery and 29 of whom required delayed surgery after an initial watch-and-wait approach.

MAIN OUTCOME MEASURES

Outcome measures included 30-day postoperative morbidity rate, hospital costs. 2-year overall and disease-free survival.

RESULTS

There was no difference in length of stay (9 vs 8; p = 0.83), readmissions (27.6% vs 10.0%; p = 0.10), surgical re-interventions (15.0% vs 3.4%; p = 0.16), or stoma-free rate (52.6% vs 31.0%; p = 0.09) between immediate and delayed surgery groups. Hospital costs were similar in the delayed group (€11,913 vs €13,769; p = 0.89). Two-year overall survival (93% vs 100%; p = 0.23) and disease-free survival (78% vs 81%; p = 0.47) rates were comparable.

LIMITATIONS

Limitations included small sample size, follow-up time and retrospective design.

CONCLUSION

Delayed surgery for regrowth in a watch-and-wait program or for persistent residual disease after a repeated assessment is not associated with an increased risk of postoperative morbidity or a significant rise in costs compared to immediate total mesorectal excision. There also appears to be no evident compromise in oncological outcome. Repeated response assessment in patients with a near complete clinical response after neoadjuvant chemoradiotherapy is a useful approach to identify more patients who can benefit from a watch-and-wait strategy. See Video Abstract at http://links.lww.com/DCR/B836 .

CIRUGA DE TME RETRASADA EN UNA ESTRATEGIA DE WATCH AND WAIT DESPUS DE LA QUIMIORRADIOTERAPIA NEOADYUVANTE PARA CNCER DE RECTO UN ANLISIS DE COSTOS HOSPITALARIOS, Y DE RESULTADOS QUIRRGICOS Y ONCOLGICOS

ANTECEDENTES: Una estrategia de Watch and Wait para pacientes con cáncer de recto con una respuesta clínica completa después de quimiorradioterapia neoadyuvante es una alternativa valiosa en vez de resección rectal. Sin embargo, hay pacientes que tendrán tumor residual o un recrecimiento durante el Watch and Wait .OBJETIVO: El objetivo fue investigar la seguridad y los costos para los pacientes que se sometieron a una cirugía diferida después de la quimiorradioterapia neoadyuvante.DISEÑO: Este es un estudio de cohorte retrospectivo con datos recolectados prospectivamente.AJUSTE: El estudio se llevó a cabo en un gran hospital universitario.PACIENTES: Entre enero de 2015 y mayo de 2020, se atendieron 622 nuevos pacientes con cáncer de recto, de los cuales 200 recibieron quimiorradioterapia neoadyuvante. Se incluyeron 94 pacientes, de los cuales 65 se sometieron a cirugía inmediata y 29 pacientes requirieron cirugía diferida después de un enfoque inicial de observación y espera.PRINCIPALES MEDIDAS DE RESULTADO: se incluyeron la tasa de morbilidad posoperatoria a 30 días, los costos hospitalarios y las sobrevidas general y libre de enfermedad a dos años.RESULTADOS: No hubo diferencia en la duración de la estancia (9 vs 8, p = 0,83), reingresos (27,6% vs 10,0%, p = 0,10), reintervenciones quirúrgicas (15,0% vs 3,4%, p = 0,16) y tasa libre de estoma (52,6% vs 31,0%, p = 0,09) entre los grupos de cirugía inmediata y tardía. Los costos hospitalarios fueron similares en el grupo retrasado (11913 € frente a 13769 €, p = 0,89). Las tasas de sobrevida general a dos años (93% frente a 100%, p = 0,23) y sobrevida libre de enfermedad (78% frente a 81%, p = 0,47) fueron comparables.LIMITACIONES: Tamaño de muestra pequeño, tiempo de seguimiento y diseño retrospectivo.CONCLUSIÓN: La cirugía tardía para el recrecimiento en un programa de Watch and Wait o para la enfermedad residual persistente después de una evaluación repetida no se asocia con un riesgo mayor de morbilidad posoperatoria ni con un aumento significativo en los costos, en comparación con la escisión total de mesorrecto inmediata. Tampoco parece haber un compromiso evidente en el resultado oncológico. La evaluación repetida de la respuesta en pacientes con una respuesta clínica casi completa después de la quimiorradioterapia neoadyuvante es un enfoque útil para identificar más pacientes que pueden beneficiarse de una estrategia de Watch and Wait . Consulte Video Resumen en http://links.lww.com/DCR/B836 . (Traducción-Dr. Juan Carlos Reyes ).

Pelvic CT in addition to MRI to differentiate between rectal and sigmoid cancer on imaging using the sigmoid take-off as a landmark

BACKGROUND

The sigmoid take-off (STO) is a recently established landmark to discern rectal from sigmoid cancer on imaging. STO-assessment can be challenging on magnetic resonance imaging (MRI) due to varying axial planes.

PURPOSE

To establish the benefit of using computed tomography (CT; with consistent axial planes), in addition to MRI, to anatomically classify rectal versus sigmoid cancer using the STO.

MATERIAL AND METHODS

A senior and junior radiologist retrospectively classified 40 patients with rectal/rectosigmoid cancers using the STO, first on MRI-only (sagittal and oblique-axial views) and then using a combination of MRI and axial CT. Tumors were classified as rectal/rectosigmoid/sigmoid (according to published STO definitions) and then dichotomized into rectal versus sigmoid. Diagnostic confidence was documented using a 5-point scale.

RESULTS

Adding CT resulted in a change in anatomical tumor classification in 4/40 cases (10%) for the junior reader and in 6/40 cases (15%) for the senior reader. Diagnostic confidence increased significantly after adding CT for the junior reader (mean score 3.85 vs. 4.27; P < 0.001); confidence of the senior reader was not affected (4.28 vs. 4.25; P = 0.80). Inter-observer agreement was similarly good for MRI only (κ=0.77) and MRI + CT (κ=0.76). Readers reached consensus on the classification of rectal versus sigmoid cancer in 78%-85% of cases.

CONCLUSION

Availability of a consistent axial imaging plane - in the case of this study provided by CT - in addition to a standard MRI protocol with sagittal and oblique-axial imaging views can be helpful to more confidently localize tumors using the STO as a landmark, especially for more junior readers.

Watch-and-Wait is an Option in Rectal Cancer Patients: From Controversy to Common Clinical Practice

Overview of the introduction of organ preservation in rectal cancer patients and future challenges.

MRI anatomy of the rectum: key concepts important for rectal cancer staging and treatment planning

A good understanding of the MRI anatomy of the rectum and its surroundings is pivotal to ensure high-quality diagnostic evaluation and reporting of rectal cancer. With this pictorial review, we aim to provide an image-based overview of key anatomical concepts essential for treatment planning, response evaluation and post-operative assessment. These concepts include the cross-sectional anatomy of the rectal wall in relation to T-staging; differences in staging and treatment between anal and rectal cancer; landmarks used to define the upper and lower boundaries of the rectum; the anatomy of the pelvic floor and anal canal, the mesorectal fascia, peritoneum and peritoneal reflection; and guides to help discern different pelvic lymph node stations on MRI to properly stage regional and non-regional rectal lymph node metastases. Finally, this review will highlight key aspects of post-treatment anatomy, including the assessment of radiation-induced changes and the evaluation of the post-operative pelvis after different surgical resection and reconstruction techniques.

The Risk of Distant Metastases in Patients With Clinical Complete Response Managed by Watch and Wait After Neoadjuvant Therapy for Rectal Cancer: The Influence of Local Regrowth in the International Watch and Wait Database

BACKGROUND

Nearly 30% of patients with rectal cancer develop local regrowth after initial clinical complete response managed by watch and wait. These patients might be at higher risk for distant metastases.

OBJECTIVE

This study aimed to investigate risk factors for distant metastases using time-dependent analyses.

DESIGN

Data from an international watch and wait database were retrospectively reviewed. Cox regression analysis was used to determine risk factors for worse distant metastases-free survival. Conditional survival modeling was used to investigate the impact of risk factors on the development of distant metastases.

SETTING

Retrospective, multicenter database.

PATIENTS

A total of 793 patients (47 institutions) with rectal cancer and clinical complete response to neoadjuvant treatment from the International Watch & Wait Database were included.

MAIN OUTCOME MEASURES

Distant metastases-free survival.

RESULTS

Of the 793 patients managed with watch and wait (median follow-up 55.2 mo)' 85 patients (10.7%) had distant metastases. Fifty-one of 85 patients (60%) had local regrowth at any time. Local regrowth was an independent factor associated with worse distant metastases-free survival in the multivariable model. Using conditional estimates, patients with local regrowth without distant metastases for 5 years (from decision to watch and wait) remained at higher risk for development of distant metastases for 1 subsequent year compared to patients without local regrowth (5-year conditional distant metastases-free survival 94.9% vs 98.4%).

LIMITATIONS

Lack of information on adjuvant chemotherapy, salvage surgery for local regrowth, and heterogeneity of individual surveillance/follow-up strategies used may have affected results.

CONCLUSIONS

In patients with clinical complete response managed by watch and wait, development of local regrowth at any time is a risk factor for distant metastases. The risk of distant metastases remains higher for 5 years after development of local regrowth. See Video Abstract at http://links.lww.com/DCR/C53.

EL RIESGO DE METSTASIS A DISTANCIA EN PACIENTES CON RESPUESTA CLNICA COMPLETA MANEJADA POR WATCH AND WAIT DESPUS DE LA TERAPIA NEOADYUVANTE PARA EL CNCER DE RECTO LA INFLUENCIA DEL NUEVO CRECIMIENTO LOCAL EN LA BASE DE DATOS INTERNACIONAL WATCH AND WAIT

ANTECEDENTES:Casi el 30 % de los pacientes con cáncer de recto desarrollan un nuevo crecimiento local después de la respuesta clínica completa inicial manejada por watch and wait. Estos pacientes podrían tener un mayor riesgo de metástasis a distancia.OBJETIVO:Investigar los factores de riesgo de metástasis a distancia mediante análisis dependientes del tiempo.DISEÑO:Se revisó retrospectivamente los datos de la base de datos internacional de Watch and Wait. Se utilizó el análisis de regresión de Cox para determinar los factores de riesgo de peor sobrevida libre de metástasis a distancia. Se utilizó un modelo de sobrevida condicional para investigar el impacto de los factores de riesgo en el desarrollo de metástasis a distancia. El tiempo transcurrido hasta el evento se calculó utilizando la fecha de decisión para watch and wait y la fecha del nuevo crecimiento local para el diagnóstico de metástasis a distancia.ESCENARIOBase de datos multicéntrica retrospectiva.PACIENTES:Se incluyeron un total de 793 pacientes (47 instituciones) con cáncer de recto y respuesta clínica completa al tratamiento neoadyuvante de la base de datos internacional de Watch and Wait.PRINCIPALES MEDIDAS DE RESULTADO:Desarrollo de metástasis a distancia.RESULTADOS:De los 793 pacientes tratados con watch and wait (mediana de seguimiento de 55,2 meses), 85 (10,7%) tenían metástasis a distancia. 51 de 85 (60%) tuvieron recrecimiento local en algún momento. El recrecimiento local fue un factor independiente asociado a una peor supervivencia libre de metástasis a distancia en el modelo multivariable. Además, al usar estimaciones condicionales, los pacientes con recrecimiento local sin metástasis a distancia durante 5 años (desde la decisión de watch and wait) permanecieron en mayor riesgo de desarrollar metástasis a distancia durante un año subsiguiente en comparación con los pacientes sin recrecimiento local (sobrevida libre de metástasis a distancia a 5 años: recrecimiento local 94,9% frente a no recrecimiento local 98,4%).LIMITACIONES:La falta de información relacionada con el uso de quimioterapia adyuvante, las características específicas de la cirugía de rescate para el nuevo crecimient o local y la heterogeneidad de las estrategias individuales de vigilancia/seguimiento utilizadas pueden haber afectado los resultados observados.CONCLUSIONES:En pacientes con respuesta clínica completa manejados por Watch and Wait, el desarrollo de recrecimiento local en cualquier momento es un factor de riesgo para metástasis a distancia. El riesgo de metástasis a distancia sigue siendo mayor durante 5 años después del desarrollo de un nuevo crecimiento local. Consulte Video Resumen en http://links.lww.com/DCR/C53. (Traducción-Dr. Felipe Bellolio).

Comparison of MRI response evaluation methods in rectal cancer: a multicentre and multireader validation study

OBJECTIVES

To compare four previously published methods for rectal tumor response evaluation after chemoradiotherapy on MRI.

METHODS

Twenty-two radiologists (5 rectal MRI experts, 17 general/abdominal radiologists) retrospectively reviewed the post-chemoradiotherapy MRIs of 90 patients, scanned at 10 centers (with non-standardized protocols). They applied four response methods; two based on T2W-MRI only (MRI tumor regression grade (mrTRG); split-scar sign), and two based on T2W-MRI+DWI (modified-mrTRG; DWI-patterns). Image quality was graded using a 0-6-point score (including slice thickness and in-plane resolution; sequence angulation; DWI b-values, signal-to-noise, and artefacts); scores < 4 were classified below average. Mixed model linear regression was used to calculate average sensitivity/specificity/accuracy to predict a complete response (versus residual tumor) and assess the impact of reader experience and image quality. Group interobserver agreement (IOA) was calculated using Krippendorff's alpha. Readers were asked to indicate their preferred scoring method(s).

RESULTS

Average sensitivity/specificity/accuracy was 57%/64%/62% (mrTRG), 36%/79%/66% (split-scar), 40%/79%/67% (modified-mrTRG), and 37%/82%/68% (DWI-patterns); mrTRG showed higher sensitivity but lower specificity and accuracy (p < 0.001) compared to the other methods. IOA was lower for the split scar method (0.18 vs. 0.39-0.43). Higher reader experience had a significant positive effect on diagnostic performance and IOA (except for the split scar sign); below-average imaging quality had a significant negative effect on diagnostic performance. DWI pattern was selected as the preferred method by 73% of readers.

CONCLUSIONS

Methods incorporating DWI showed the most favorable results when combining diagnostic performance, IOA, and reader preference. Reader experience and image quality clearly impacted diagnostic performance emphasizing the need for state-of-the-art imaging and dedicated radiologist training.

KEY POINTS

• In a multireader study comparing 4 MRI methods for rectal tumor response evaluation, those incorporating DWI showed the best results when combining diagnostic performance, IOA, and reader preference. • The most preferred method (by 73% of readers) was the "DWI patterns" approach with an accuracy of 68%, high specificity of 82%, and group IOA of 0.43. • Reader experience level and MRI quality had an evident effect on diagnostic performance and IOA.

Defining near-complete response following (chemo)radiotherapy for rectal cancer: systematic review

BACKGROUND

A uniform definition of a clinical near-complete response (near-CR) after neoadjuvant (chemo)radiotherapy for rectal cancer is lacking. A clear definition is necessary for uniformity in clinical practice and trial enrolment for organ-preserving treatments. This review aimed to provide an overview of the terminology, criteria, and features used in the literature to define a near-CR.

METHODS

A systematic review was performed based on the PRISMA statement. PubMed and Embase were searched up to May 2021 to identify the terminology, criteria, and features used to define a near-CR after (chemo)radiotherapy for rectal cancer. Studies with no clear cut-off point between a cCR and near-CR, studies using Response Evaluation Criteria In Solid Tumours, and studies including only complete responders were excluded.

RESULTS

A total of 1876 articles were found, of which 23 were included. Patients were managed by watchful waiting and/or additional local treatment in 11 and 17 of 23 studies respectively. Response evaluation included digital rectal examination (DRE) and/or endoscopy with MRI in 18 studies. The majority of studies used the term 'near-complete response'. In most studies, minor irregularities or a smooth induration with DRE and a small flat ulcer on endoscopy were considered to indicate a near-CR. On MRI, five studies used features (obvious downstaging with or without heterogeneous/irregular fibrosis on T2-weighted MRI or small spot of high signal on diffusion-weighted imaging), five studies used TNM criteria (ycT2), and four used magnetic resonance tumour regression grade (mrTRG) (mrTRG1-2/mrTRG2) to describe a near-CR.

CONCLUSION

The terminology, criteria, and features used to describe a near-CR vary substantially, which can partly be explained by the different treatment strategies patients are selected for (watchful waiting or additional local treatment). A reproducible definition of near-CR is required.

Evaluating HEmopatch® in Reducing Seroma-Related Complications following Axillary Lymph Node DIssection: A Pilot Study (HEIDI)

Purpose

Axillary lymph node dissection (ALND) is performed to treat locoregional metastatic disease in breast cancer and melanoma patients. However, it is notorious for its complications, most commonly seroma formation and its sequelae. Ample research has been done to evaluate seroma formation after ALND; these results, however, have not been conclusive. Hence, this pilot study aimed to evaluate a readily available haemostatic patch, Hemopatch®, to assess its effect on seroma formation following ALND.

Methods

In this pilot study, a prospective cohort of 20 patients receiving Hemopatch® following ALND was compared to a retrospective cohort of patients who underwent ALND between 2014 and 2019. The primary outcome measure was the number of patients developing clinically significant seroma (CSS) after ALND. Additionally, the number of wound complications, subsequent interventions, additional outpatient clinic visits, and drain output was assessed. Differences between groups were deemed clinically relevant if the proportions differed >50% between groups.

Results

In total, 20 prospective and 42 retrospective patients were included. In the Hemopatch® group, 30% of the patients developed CSS, compared to 43% in the control group. Three patients in both groups developed a surgical site infection. Thirty-five percent of patients in the Hemopatch® group required additional unscheduled visits versus 62% of patients in the control group.

Conclusion

The application of Hemopatch® after ALND did not lead to a clinically relevant reduction of CSS and wound complications. However, fewer Hemopatch® patients required additional outpatient clinic visits. Due to the limited amount of participants, the true value of Hemopatch® in ALND remains unclear.

Minimum standards of pelvic exenterative practice: PelvEx Collaborative guideline

This document outlines the important aspects of caring for patients who have been diagnosed with advanced pelvic cancer. It is primarily aimed at those who are establishing a service that adequately caters to this patient group. The relevant literature has been summarized and an attempt made to simplify the approach to management of these complex cases.

Sentinel lymph node mapping with superparamagnetic iron oxide for melanoma: a pilot study in healthy participants to establish an optimal MRI workflow protocol

BACKGROUND

Current pre-operative Sentinel Lymph Node (SLN) mapping using dual tracing is associated with drawbacks (radiation exposure, logistic challenges). Superparamagnetic iron oxide (SPIO) is a non-inferior alternative for SLN mapping in breast cancer patients. Limited research has been performed on SPIO use and pre-operative MRI in melanoma patients to identify SLNs.  METHODS: Healthy participants underwent MRI-scanning pre- and post SPIO-injection during 20 min. Workflow protocols varied in dosage, massage duration, route of administration and injection sites. The first lymph node showing a susceptibility artefact caused by SPIO accumulation was considered as SLN.

RESULTS

Artefacts were identified in 5/6 participants. Two participants received a 0.5 ml subcutaneous injection and 30-s massage, of which one showed an artefact after one hour. Four participants received a 1.0 ml intracutaneous injection and two-minute massage, leading to artefacts in all participants. All SLNs were observed within five minutes, except after lower limb injection (30 min).

CONCLUSION

SPIO and pre-operative MRI-scanning seems to be a promising alternative for SLN visualization in melanoma patients. An intracutaneous injection of 1.0 ml SPIO tracer, followed by a two-minute massage seems to be the most effective technique, simplifying the pre-operative pathway. Result will be used in a larger prospective study with melanoma patients.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT05054062) - September 9, 2021.

Technical aspects of flap fixation after mastectomy for breast cancer: Guidelines for improving seroma-related outcome

OBJECTIVES

Previous studies have identified the added value of flap fixation in reducing seroma formation and its sequelae after mastectomy. The seroma reduction after mastectomy (SAM)-trial proved that sutures were superior to tissue glue. In this article, we will elaborate on the results of the SAM-trial to provide a clear surgical guideline.

METHODS

All patients in the suture flap fixation cohort from the SAM-trial were analyzed if details regarding flap fixation were available. The most optimal number of sutures was determined using a receiving operator characteristics curve. The incidence of seroma formation between patients receiving the most optimal number of sutures and patients receiving fewer sutures was compared.

RESULTS

The most optimal number of sutures proved to be 15. Patients with ≥15 sutures had a lower incidence of seroma formation at every time frame during follow-up. There was a significant difference at 6 weeks (odds ratio [OR]: 3.05, 95% confidence interval [CI]: 1.09-8.56), 3 months (OR: 4.62, 95% CI: 1.34-12.92), and 1 year postoperatively (OR: 20.48, 95% CI: 2.18-192.22). Ten days and 6 months postoperatively did not differ significantly.

CONCLUSIONS

Flap fixation in general, but also the surgical technique influences the incidence of seroma formation after mastectomy. Results suggest a minimum of 15 sutures, spaced approximately 3.7 cm apart.

Use of Image-Guided Surgical Navigation during Resection of Locally Recurrent Rectal Cancer

Surgery for locally recurrent rectal cancer (LRRC) presents several challenges, which is why the percentage of inadequate resections of these tumors is high. In this exploratory study, we evaluate the use of image-guided surgical navigation during resection of LRRC. Patients who were scheduled to undergo surgical resection of LRRC who were deemed by the multidisciplinary team to be at a high risk of inadequate tumor resection were selected to undergo surgical navigation. The risk of inadequate surgery was further determined by the proximity of the tumor to critical anatomical structures. Workflow characteristics of the surgical navigation procedure were evaluated, while the surgical outcome was determined by the status of the resection margin. In total, 20 patients were analyzed. For all procedures, surgical navigation was completed successfully and demonstrated to be accurate, while no complications related to the surgical navigation were discerned. Radical resection was achieved in 14 cases (70%). In five cases (25%), a tumor-positive resection margin (R1) was anticipated during surgery, as extensive radical resection was determined to be compromised. These patients all received intraoperative brachytherapy. In one case (5%), an unexpected R1 resection was performed. Surgical navigation during resection of LRRC is thus safe and feasible and enables accurate surgical guidance.

Selected stage IV rectal cancer patients managed by the watch-and-wait approach after pelvic radiotherapy: a good alternative to total mesorectal excision surgery?

AIM

The aim of this study was to assess the clinical and oncological outcome of a selected group of stage IV rectal cancer patients managed by the watch-and-wait approach following a (near-)complete response of the primary rectal tumour after radiotherapy.

METHOD

Patients registered in the Dutch watch-and-wait registry since 2004 were selected when diagnosed with synchronous stage IV rectal cancer. Data on patient characteristics, treatment details, follow-up and survival were collected. The 2-year local regrowth rate, organ-preservation rate, colostomy-free rate, metastatic progression-free rate and 2- and 5-year overall survival were analysed.

RESULTS

After a median follow-up period of 35 months, local regrowth was observed in 17 patients (40.5%). Nine patients underwent subsequent total mesorectal excision, resulting in a permanent colostomy in four patients. The 2-year local regrowth rate was 39.9%, the 2-year organ-preservation rate was 77.1%, the 2-year colostomy-free rate was 88.1%, and the 2-year metastatic progression-free rate was 46.7%. The 2- and 5-year overall survival rates were 92.0% and 67.5%.

CONCLUSION

The watch-and-wait approach can be considered as an alternative to total mesorectal excision in a selected group of stage IV rectal cancer patients with a (near-)complete response following pelvic radiotherapy. Despite a relatively high regrowth rate, total mesorectal excision and a permanent colostomy can be avoided in the majority of these patients.

Current controversies in TNM for the radiological staging of rectal cancer and how to deal with them: results of a global online survey and multidisciplinary expert consensus

Objectives

To identify the main problem areas in the applicability of the current TNM staging system (8th ed.) for the radiological staging and reporting of rectal cancer and provide practice recommendations on how to handle them.

Methods

A global case-based online survey was conducted including 41 image-based rectal cancer cases focusing on various items included in the TNM system. Cases reaching < 80% agreement among survey respondents were identified as problem areas and discussed among an international expert panel, including 5 radiologists, 6 colorectal surgeons, 4 radiation oncologists, and 3 pathologists.

Results

Three hundred twenty-one respondents (from 32 countries) completed the survey. Sixteen problem areas were identified, related to cT staging in low-rectal cancers, definitions for cT4b and cM1a disease, definitions for mesorectal fascia (MRF) involvement, evaluation of lymph nodes versus tumor deposits, and staging of lateral lymph nodes. The expert panel recommended strategies on how to handle these, including advice on cT-stage categorization in case of involvement of different layers of the anal canal, specifications on which structures to include in the definition of cT4b disease, how to define MRF involvement by the primary tumor and other tumor-bearing structures, how to differentiate and report lymph nodes and tumor deposits on MRI, and how to anatomically localize and stage lateral lymph nodes.

Conclusions

The recommendations derived from this global survey and expert panel discussion may serve as a practice guide and support tool for radiologists (and other clinicians) involved in the staging of rectal cancer and may contribute to improved consistency in radiological staging and reporting.

Key Points

• Via a case-based online survey (incl. 321 respondents from 32 countries), we identified 16 problem areas related to the applicability of the TNM staging system for the radiological staging and reporting of rectal cancer.

• A multidisciplinary panel of experts recommended strategies on how to handle these problem areas, including advice on cT-stage categorization in case of involvement of different layers of the anal canal, specifications on which structures to include in the definition of cT4b disease, how to define mesorectal fascia involvement by the primary tumor and other tumor-bearing structures, how to differentiate and report lymph nodes and tumor deposits on MRI, and how to anatomically localize and stage lateral lymph nodes.

• These recommendations may serve as a practice guide and support tool for radiologists (and other clinicians) involved in the staging of rectal cancer and may contribute to improved consistency in radiological staging and reporting.

Timing of Primary Tumor Resection in Synchronous Metastatic Colon Cancer Patients Undergoing Hepatic Arterial Infusion Pump Placement

INTRODUCTION

Hepatic arterial infusion (HAI) chemotherapy is associated with improved survival in stage IV colon cancer with liver metastases. Whether simultaneous colon resection and HAI pump (HAIP) placement is associated with increased morbidity has not been specifically studied. The purpose of this study was to compare perioperative outcomes of simultaneous colon resection and HAIP placement versus HAIP placement alone.

METHODS

This was a retrospective study of consecutive patients with colon cancer and synchronous liver metastases who underwent HAIP placement between 2007 and 2018. Clinicopathologic characteristics, operative data, complications, and time to first cycle of HAIP chemotherapy were compared between patients who underwent colon resection simultaneously with HAIP placement and those who underwent HAIP placement alone.

RESULTS

A total of 258 patients underwent simultaneous colectomy and HAIP placement, and 116 patients underwent HAIP placement alone. Grade 1-2 complications were more common in patients who underwent simultaneous colectomy and HAIP placement (36.8% vs. 19.0%, P < 0.001), but grade 3-4 complications were not observed more frequently (14.3% vs. 12.9%, P = 0.872). The median interval between HAIP placement and start of HAIP chemotherapy did not differ between groups (simultaneous colectomy, 27 days [interquartile range (IQR) 17-34]; HAIP placement alone, 30 days [IQR 21-34]; P = 0.924). Infection of the pump causing either delay of initiation of chemotherapy or explantation of the pump occurred in five patients with simultaneous colectomy and in one patient with HAIP placement alone (P = 0.671).

CONCLUSIONS

Simultaneous HAIP implantation and colectomy is safe in patients with liver metastases of colon carcinoma.

Evolutions in rectal cancer MRI staging and risk stratification in The Netherlands

Purpose

To analyze how the MRI reporting of rectal cancer has evolved (following guideline updates) in The Netherlands.

Methods

Retrospective analysis of 712 patients (2011–2018) from 8 teaching hospitals in The Netherlands with available original radiological staging reports that were re-evaluated by a dedicated MR expert using updated guideline criteria. Original reports were classified as “free-text,” “semi-structured,” or “template” and completeness of reporting was documented. Patients were categorized as low versus high risk, first based on the original reports (high risk = cT3-4, cN+, and/or cMRF+) and then based on the expert re-evaluations (high risk = cT3cd-4, cN+, MRF+, and/or EMVI+). Evolutions over time were studied by splitting the inclusion period in 3 equal time periods.

Results

A significant increase in template reporting was observed (from 1.6 to 17.6–29.6%; p < 0.001), along with a significant increase in the reporting of cT-substage, number of N+ and extramesorectal nodes, MRF invasion and tumor-MRF distance, EMVI, anal sphincter involvement, and tumor morphology and circumference. Expert re-evaluation changed the risk classification from high to low risk in 18.0% of cases and from low to high risk in 1.7% (total 19.7%). In the majority (17.9%) of these cases, the changed risk classification was likely (at least in part) related to use of updated guideline criteria, which mainly led to a reduction in high-risk cT-stage and nodal downstaging.

Conclusion

Updated concepts of risk stratification have increasingly been adopted, accompanied by an increase in template reporting and improved completeness of reporting. Use of updated guideline criteria resulted in considerable downstaging (of mainly high-risk cT-stage and nodal stage).

Graphic abstract

Contact X-ray Brachytherapy for Older or Inoperable Rectal Cancer Patients: Short-Term Oncological and Functional Follow-Up

Total mesorectal excision for rectal cancer is a major operation associated with morbidity and mortality. For older or inoperable patients, alternatives are necessary. This prospective study evaluated the oncological and functional outcome and quality of life of older or inoperable rectal cancer patients treated with a contact X-ray brachytherapy boost to avoid major surgery. During follow-up, tumor response and toxicity on endoscopy were scored. Functional outcome and quality of life were assessed with self-administered questionnaires. Additionally, in-depth interviews regarding patients' experiences were conducted. Nineteen patients were included with a median age of 80 years (range 72-91); nine patients achieved a clinical complete response and in another four local control of the tumor was established. The 12 month organ-preservation rate, progression-free survival, and overall survival were 88%, 78%, and 100%, respectively. A transient decrease in quality of life and bowel function was observed at 3 months, which was generally restored at 6 months. In-depth interviews revealed that patients' experience was positive despite the side-effects shortly after treatment. In older or inoperable rectal cancer patients, contact X-ray brachytherapy can be considered an option to avoid total mesorectal excision. Contact X-ray brachytherapy is well-tolerated and can provide good tumor control.