Correlative Significance of Tumor Regression Grade and ypT Category in Patients Undergoing Preoperative Chemoradiotherapy for Locally Advanced Rectal Cancer

BACKGROUND

In patients with locally advanced rectal cancer, the treatment response to preoperative chemoradiotherapy (PRCRT) varies, and the ypT stage may change as a result of tumor shrinkage. The purpose of this study was to evaluate the correlative significance and determine the prognostic value of tumor regression grade and ypT category staging systems.

MATERIALS AND METHODS

This retrospective observational study was conducted in a tertiary center. A total of 1240 patients with rectal cancer who underwent curative resection after PRCRT between January 2007 and December 2016 were consecutively included.

RESULTS

A significant association was found between the American Joint Committee on Cancer/College of American Pathology tumor regression grading system and ypT category, indicating a potential correlation between worse tumor regression grade and more advanced T stage (Cramer's V = 0.255, P < .001). The ypT stage and tumor regression grade were independent predictors of each other (P < .001). The good response group (tumor regression grades 0-1) had significantly higher 5-year disease-free survival (85.5% vs. 68.2%, P < .001) and overall survival (92.1% vs. 81.0%, P < .001) rates than the poor response group (tumor regression grades 2-3). However, the ypT and ypN categories were the most important independent prognostic factors for disease-free and overall survival.

CONCLUSIONS

Tumor regression grade and ypT category were significantly correlated. Although tumor regression grade alone is not definitive, it is closely related to the ypT stage and impacts oncologic outcomes. These findings should be taken into consideration when stratifying the prognosis of patients undergoing PRCRT.

Pathologic Implications of Radial Resection Margin and Perineural Invasion to Adjuvant Chemotherapy after Preoperative Chemoradiotherapy and Surgery for Rectal Cancer: A Multi-Institutional and Case-Matched Control Study

We assessed the exact role of adjuvant chemotherapy after neoadjuvant chemoradiotherapy (CRT) and surgery in rectal cancer patients with positive surgical margin or perineural invasion (PNI). This multi-institutional study included 1799 patients with rectal cancer at cT3-4N0-2M0 stages. Patients were divided into two groups. The high-risk group had a positive margin and/or perineural invasion. The low-risk group showed no positive margin or PNI. Propensity-score matching analysis was performed, and a total of 928 patients, with 464 in each arm, were evaluated. The high-risk group showed significant differences in overall survival (OS, 73.4% vs. 53.9%, p < 0.01) and recurrence-free survival (RFS, 52.7% vs. 40.9%, p = 0.01) at five years between the adjuvant chemotherapy arm and observation arm. The low-risk group showed no significant differences in 5-year OS (p = 0.61) and RFS (p = 0.75) between the two arms. Multivariate analyses showed that age, pathologic N stage, and adjuvant chemotherapy were significantly correlated with OS and RFS in the high-risk group (all p < 0.05). Adjuvant chemotherapy improved OS and RFS more significantly in rectal cancer patients with positive surgical margin or PNI than in those with negative surgical margin and PNI.

Is a Distal Resection Margin of ≤ 1 cm Safe in Patients with Intermediate- to Low-Lying Rectal Cancer? A Systematic Review and Meta-Analysis

BACKGROUND

It is generally accepted that the distal resection margin of intermediate- to low-lying rectal cancer should be greater than 2 cm and at least 1 cm in special cases. This study intends to investigate whether a distal resection margin ≤ 1 cm affects tumor outcomes for patients with intermediate- to low-lying rectal cancer.

METHODS

A systematic review of the literature was conducted. Sixteen studies included data for distal resection margins ≤ 1 cm (1684 cases) and > 1 cm (5877 cases), and 5 studies included survival data. Meta-analysis was used to compare the local recurrence rate and long-term survival of patients with distal resection margins > or ≤ 1 cm.

RESULTS

The local recurrence rate in the ≤ 1-cm margin group (9.5%) was 2.3% higher than that in the > 1-cm margin group (7.2%) according to a fixed-effects model (RR [95% CI] 1.42 [1.18, 1.70], P < 0.001). The overall survival results of the five 1-cm margin studies showed an HR (95% CI) of 0.96 (0.75, 1.24) (P = 0.78). Subgroup analysis showed that the local recurrence rate in the subgroup with perioperative treatment was 1.2% lower in the ≤ 1-cm margin group (8.3%) than in the > 1-cm margin group (9.5%) (RR [95% CI] 0.97 [0.63, 1.49], P = 0.90). In the surgery alone subgroup, the local recurrence rate was 4.7% higher in the ≤ 1-cm margin group (12.4%) than in the > 1-cm group (7.7%) (RR [95% CI] 1.76 [1.09, 2.83], P = 0.02).

CONCLUSIONS

For patients with intermediate- to low-lying rectal cancer undergoing surgery alone, a distal resection margin ≤ 1 cm may be not safe.

Tailored Strategy for Locally Advanced Rectal Carcinoma (GRECCAR 4): Long-term Results From a Multicenter, Randomized, Open-Label, Phase II Trial

BACKGROUND

Systematic preoperative radiochemotherapy and total mesorectal excision are the standard of care for locally advanced rectal carcinoma. Some patients can be over- or undertreated.

OBJECTIVE

This study aimed to investigate the long-term oncological, functional, and late morbidity outcomes after tailored radiochemotherapy and induction high-dose chemotherapy.

DESIGN

This is a prospective, phase II, multicenter, open-label study at 16 tertiary centers in France.

SETTINGS

Patients were operated on by surgeons from the French GRECCAR group.

PATIENTS

Two hundred six patients were randomly assigned to treatment: good responders after chemotherapy (≥75% tumor volume reduction) to immediate surgery (arm A) or standard radiochemotherapy (capecitabine 50) plus surgery (arm B) and poor responders to capecitabine 50 (arm C) or intensive radiochemotherapy (capecitabine 60; 60 Gy irradiation; arm D) before surgery.

INTERVENTIONS

Treatment was tailored according to MRI response to induction chemotherapy.

RESULTS

After induction treatment, 194 patients were classified as good (n = 30, 15%) or poor (n = 164, 85%) responders; they were included in arms A and B (16 and 14 patients) or C and D (113 and 51 patients). The primary objective was obtained: R0 resection rates (90% CI) in the 4 arms were 100% (74-100), 100% (85-100), 83% (72-91), and 88% (77-95). At 5 years, overall survival rates were 90% (47.3-98.5), 93.3% (61.3-99.0), 84.3% (71.0-91.8), and 86.1% (71.6-93.5); disease-free survival rates were 80% (40.9-94.6), 89.5% (64.1-97.3), 72.9% (58.5-82.9), and 72.8% (57.7-83.2); local recurrence rates were 0%, 0%, 2.1% (0.3-13.9), and 9.3% (3.6-23.0); and metastasis rates were 20% (5.4-59.1), 10.5% (2.7-35.9), 18% (31.8-94.6), and 18.8% (10.2-33.0). Late morbidity and quality-of-life evaluations showed no significant difference between arms.

LIMITATIONS

Limitations were due to the small number of patients randomly assigned in the good responder arms, especially arm A without radiotherapy.

CONCLUSION

Tailoring preoperative radiochemotherapy based on induction treatment response appears to be promising. Future prospective trials should confirm this strategy. See Video Abstract at http://links.lww.com/DCR/B761 .

REGISTRATION

URL: https://www.clinicaltrials.gov ; Identifier: NCT01333709.

ESTRATEGIA HECHA A MEDIDA PARA EL TRATAMIENTO DEL CARCINOMA DE RECTO LOCALMENTE AVANZADO GRECCAR RESULTADOS A LARGO PLAZO DE UN ESTUDIO ALEATRIO MULTICNTRICO Y ABIERTO DE FASE II

ANTECEDENTES:La radio-quimioterapia pré-operatoria sistemáticas y la excisión total del mesorrecto son el estándar en el tratamiento del carcinoma de recto localmente avanzado. En éste sentido, algunos pacientes podrían recibir un sobre o un infra-tratamiento.OBJETIVO:Evaluar los resultados oncológicos, funcionales y de morbilidad a largo plazo después de radio-quimioterapia personalizada y quimioterapia de inducción a dosis elevadas.DISEÑO:Estudio aleatório multicéntrico y abierto de Fase II° realizado en 16 centros terciarios en Francia.AJUSTE:Aquellos pacientes operados por cirujanos del grupo GRECCAR francés.PACIENTES:206 pacientes fueron asignados aleatoriamente al tratamiento: los buenos respondedores después de quimioterapia (reducción del volumen tumoral ≥75%) a la cirugía inmediata (brazo A) o a la radio-quimioterapia estándar (Cap 50) asociada a la cirugía (brazo B); los malos respondedores a Cap 50 (brazo C) o a la radio-quimioterapia intensiva (Cap 60 (irradiación de 60 Gy) (brazo D) previas a la cirugía.INTERVENCIONES:Tratamiento adaptado según la respuesta de la RM a la TC de inducción.RESULTADOS:Después del tratamiento de inducción, 194 pacientes fueron clasificados como buenos (n = 30, 15%) o malos (n = 164, 85%) respondedores, y se incluyeron en los brazos A y B (16 y 14 pacientes) o C y D (113 y 51 pacientes). Se alcanzó el objetivo principal: las tasas de resección R0 [intervalo de confianza del 90%] en los cuatro brazos respectivamente, fueron del 100% [74-100], 100% [85-100], 83% [72-91] y 88% [77-95]. A los 5 años, las tasas fueron: de sobrevida global 90% [47,3-98,5], 93,3% [61,3-99,0], 84,3% [71,0-91,8], 86,1% [71,6-93,5]; de sobrevida libre a la enfermedad 80% [40,9-94,6], 89,5% [64,1-97,3], 72,9% [58,5-82,9], 72,8% [57,7-83,2]; de recidiva local 0, 0, 2,1% [0,3-13,9], 9,3% [3,6-23,0]; de metástasis 20% [5,4-59,1], 10,5% [2,7-35,9], 18% [31,8-94,6], 18,8% [10,2-33,0]. La evaluación tardía de la morbilidad y la calidad de vida no mostraron diferencias significativas entre los brazos.LIMITACIONES:Debido al pequeño número de pacientes asignados al azar en los brazos de buenos respondedores, especialmente en el brazo A de aquellos sin radioterapia.CONCLUSIÓN:Parecería muy prometedor el adaptar la radio-quimioterapia pré-operatoria basada en la respuesta al tratamiento de inducción. Estudios prospectivos en el futuro podrán confirmar la presente estrategia. Consulte Video Resumen en http://links.lww.com/DCR/B761 . (Traducción-Dr. Xavier Delgadillo )IDENTIFICADOR DE CLINICALTRIALS.GOV:NCT01333709. Groupe de REcherche Chirurgicale sur le CAncer du Rectum.

Tumor-microenvironment triggered signal-to-noise boosting nanoprobes for NIR-IIb fluorescence imaging guided tumor surgery and NIR-II photothermal therapy

High quantum yield quantum dots (QDs) with the emission in the sub-second near infrared window (NIR-IIb, 1500-1700 nm) can afford higher resolution, a deeper penetration depth and zero auto-fluorescence for bio-imaging. However, low tumor accumulation, the rapid renal clearance and potential toxicity impeding their biomedical applications. Here, we report a tumor microenvironment responsive hollowed virus-bionic MnO2 nanoshell with IR1061 loading in the cavity and QDs (PbS@CdS) anchoring on the surface for precise NIR-IIb fluorescence imaging guided tumor surgery and efficient NIR-II photothermal therapy. This QDs based nanoprobe could efficiently adhere on tumor cells to realize efficient tumor tissue accumulation. NIR-IIb fluorescence of tumor margin could be successfully delineating after extracellular weak acid triggered MnO2 biodegradation for IR1061 release with remarkable NIR-IIb signal-to-noise boosting. Then, it could facilitate complete dissection of various tumor models with the assistance of NIR-IIb fluorescence imaging. Moreover, the fascinating efficacy for micro-metastasis eradication via NIR-II photothermal effects can be achieved under NIR-IIb fluorescence imaging guidance. Specifically, in combination with negligible system toxicity, our nanoprobes showed great potential as a versatile NIR-IIb fluorescent imaging platform for precise tumor surgery and tumor therapy guidance for future clinical translation.

Rectal cancer at the peritoneal reflection. Preoperative MRI accuracy and histophatologic correlation. Prospective study

INTRODUCTION

To investigate magnetic resonance imaging (MRI) accuracy for determining the location of rectal tumors with respect to the peritoneal reflection (PR) and its potential involvement.

METHODS

Prospective study of 161 patients ongoing surgery for rectal cancer. A double-ink method has been aplied to examine surgical specimen, orange ink for the serosal surface and indian ink for the mesorrectal margin, and assess preoperative MRI accuracy.

RESULTS

Twenty-two tumors were located above, 65 at and 74 below PR. MRI accuracy was 90.6% for determining tumor's location with respect to the PR and 80.5% for defining peritoneal involvement. For classifying tumors according to their intra or extraperitoneal location an accuracy of 92.5% was set for MRI. Histophatologic peritoneal involvement was found in 28.7% of tumors located above or at the PR.

CONCLUSIONS

Magnetic resonance imaging accurately predicts the location of rectal tumors with respect to the PR and its potential involvement. The double-ink method is useful to assess serosal involvement (pT4a) and to distinguish mesorrectal fascia from the peritonealized surface.

High Dose Rate Brachytherapy Boost After Chemoradiation in Rectal Cancer Patients: A Retrospective Study

Background: The use of neoadjuvant chemoradiation has enhanced local control in rectal cancer patients. Objectives: The aim of this study was to evaluate the feasibility and efficacy of adding a high dose rate (HDR) brachytherapy (BRT) boost in locally advanced rectal cancer. Methods: This retrospective trial was conducted based on the medical records of patients with rectal cancer, who were referred to a tertiary hospital for neoadjuvant treatment. Fifteen patients who were treated with HDR brachytherapy boost after completion of external beam radiotherapy (EBRT) and concurrent chemotherapy were enrolled in the intervention group and 15 patients who were clinically matched (age, sex, stage, and distance of tumor from anal verge) were selected as the control group. EBRT schedule and concurrent chemotherapy regimen were similar in the two groups. The rate of pathological complete response (PCR), downstaging (T staging), and frequency of side effects were compared between the two groups of the study. Results: The mean age of patients was 57.97 ± 9.11 years and 18 patients (60%) were male. The results showed that T 3 and N 1 rectal cancer had the highest frequency among patients. Downstaging was observed in 66.7% and 80% of the control and intervention groups, respectively (P: 0.40). The rate of PCR was not different in the two groups (13.3% in both groups, P > 0.99). There were no significant differences in terms of treatment complications between the two groups, as well. Conclusions: HDR-BRT boost for rectal cancer is feasible and might improve downstaging in rectal cancer, but not PCR.

Long-term outcomes after extra-levator versus conventional abdominoperineal excision for low rectal cancer

PURPOSE

Extralevator (ELAPE) and abdominoperineal excision (APE) are two major surgical approaches for low rectal cancer patients. Although excellent short-term efficacy is achieved in patients undergoing ELAPE, the long-term benefits have not been established. In this study we evaluated the safety, pathological and survival outcomes in rectal cancer patients who underwent ELAPE and APE.

METHODS

One hundred fourteen patients were enrolled, including 68 in the ELAPE group and 46 in the APE group at the Beijing Chaoyang Hospital, Capital Medical University from January 2011 to November 2020. The baseline characteristics, overall survival (OS), progression-free survival (PFS), and local recurrence-free survival (LRFS) were calculated and compared between the two groups.

RESULTS

Demographics and tumor stage were comparable between the two groups. The 5-year PFS (67.2% versus 38.6%, log-rank P = 0.008) were significantly improved in the ELAPE group compared to the APE group, and the survival advantage was especially reflected in patients with pT3 tumors, positive lymph nodes or even those who have not received neoadjuvant chemoradiotherapy. Multivariate analysis showed that APE was an independent risk factor for OS (hazard ratio 3.000, 95% confidence interval 1.171 to 4.970, P = 0.004) and PFS (hazard ratio 2.730, 95% confidence interval 1.506 to 4.984, P = 0.001).

CONCLUSION

 Compared with APE, ELAPE improved long-term outcomes for low rectal cancer patients, especially among patients with pT3 tumors, positive lymph nodes or those without neoadjuvant chemoradiotherapy.

Locally Recurrent Rectal Cancer According to a Standardized MRI Classification System: A Systematic Review of the Literature

(1) Background: The classification of locally recurrent rectal cancer (LRRC) is not currently standardized. The aim of this review was to evaluate pelvic LRRC according to the Beyond TME (BTME) classification system and to consider commonly associated primary tumour characteristics. (2) Methods: A systematic review of the literature prior to April 2020 was performed through electronic searches of the Science Citation Index Expanded, EMBASE, MEDLINE, and CENTRAL databases. The primary outcome was to assess the location and frequency of previously classified pelvic LRRC and translate this information into the BTME system. Secondary outcomes were assessing primary tumour characteristics. (3) Results: A total of 58 eligible studies classified 4558 sites of LRRC, most commonly found in the central compartment (18%), following anterior resection (44%), in patients with an 'advanced' primary tumour (63%) and following neoadjuvant radiotherapy (29%). Most patients also classified had a low rectal primary tumour. The lymph node status of the primary tumour leading to LRRC was comparable, with 52% node positive versus 48% node negative tumours. (4) Conclusions: This review evaluates the largest number of LRRCs to date using a single classification system. It has also highlighted the need for standardized reporting in order to optimise perioperative treatment planning.

Impact of Age on Multimodality Treatment and Survival in Locally Advanced Rectal Cancer Patients

Background: Optimal treatment for locally advanced rectal cancer is neoadjuvant (chemo)radiation followed by radical surgery. This is challenging in the aging population because of frequently concomitant comorbidity. We analyzed whether age below and above 70 years is associated with differences in treatment strategy and outcome in this population-based study. Methods: Data between 2008 and 2016 were extracted from the Netherlands Cancer Registry with follow-up until 2021. Differences in therapy, referral and outcome were analyzed using χ2 tests, multivariable logistic regression and relative survival analysis. Results: In total, 6524 locally advanced rectal cancer patients were included. A greater proportion of patients <70 years underwent resection compared to older patients (89% vs. 71%). Patients ≥70 years were more likely treated with neoadjuvant radiotherapy (OR 3.4, 95% CI 2.61−4.52), than with chemoradiation (OR 0.3, 95% CI 0.23−0.37) and less often referred to higher volume hospitals for resection (OR 0.7, 95% CI 0.51−0.87). Five-year relative survival after resection following neoadjuvant therapy was comparable and higher for both patients <70 years and ≥70 years (82% and 77%) than after resection only. Resection only was associated with worse survival in the elderly compared to younger patients (56% vs. 75%). Conclusion: Elderly patients with locally advanced rectal cancer received less intensive treatment and were less often referred to higher volume hospitals for surgery. Relative survival was good and comparable after optimal treatment in both age groups. Effort is necessary to improve guideline adherence, and multimodal strategies should be tailored to age, comorbidity and performance status.

Regional variance in treatment and outcomes of locally invasive (T4) rectal cancer in Australia and New Zealand: analysis of the Bi-National Colorectal Cancer Audit

Backgrounds

Locally invasive T4 rectal cancer often requires neoadjuvant treatment followed by multi‐visceral surgery to achieve a radical resection (R0), and referral to a specialized exenteration quaternary centre is typically recommended. The aim of this study was to explore regional variance in treatment and outcomes of patients with locally advanced rectal cancer in Australia and New Zealand (ANZ).

Methods

Data were collected from the Bi‐National Colorectal Cancer Audit (BCCA) database. Rectal cancer patients treated between 2007 and 2019 were divided into six groups based on region (state/country) using patient postcode. A subset analysis of patients with T4 cancer was performed. Primary outcomes were positive circumferential resection margin (CRM+), and positive circumferential and/or distal resection margin (CRM/DRM+).

Results

A total of 9385 patients with rectal cancer were identified, with an overall CRM+ rate of 6.4% and CRM/DRM+ rate of 8.6%. There were 1350 patients with T4 rectal cancer (14.4%). For these patients, CRM+ rate was 18.5%, and CRM/DRM+ rate was 24.1%. Significant regional variation in CRM+ (range 13.4–26.0%; p = 0.025) and CRM/DRM+ rates (range 16.1–29.3%; p = 0.005) was identified. In addition, regions with higher CRM+ and CRM/DRM+ rates reported lower rates of multi‐visceral resections: range 24.3–26.8%, versus 32.6–37.3% for regions with lower CRM+ and CRM/DRM+ rates (p < 0.0001).

Conclusion

Positive resection margins and rates of multi‐visceral resection vary between the different regions of ANZ. A small subset of patients with T4 rectal cancer are particularly at risk, further supporting the concept of referral to specialized exenteration centres for potentially curative multi‐visceral resection.

Outcomes of rectal cancer patients with a positive pathological circumferential resection margin

PURPOSE

Evidence-based management of positive pathological circumferential resection margin (pCRM) following preoperative radiation and an adequate rectal resection for rectal cancers is lacking.

METHODS

Retrospective analysis of prospectively maintained single-centre institutional database was done to study the patterns of failure and management strategies after a rectal cancer surgery with a positive pCRM.

RESULTS

A total of 86 patients with rectal adenocarcinoma with a positive pCRM were identified over 8 years (2011-2018). Majority had low-lying rectal cancers (90.7%) and were operated after preoperative radiotherapy (95.3%). Operative procedures included abdomino-perineal resections, inter-sphincteric resections, low anterior resections and pelvic exenteration in 61 (70.9%), 9 (10.5%), 11(12.8%) and 5 (5.8%) patients respectively. A total of 83 (96.5%) received chemotherapy as the sole adjuvant treatment modality while 2 patients (2.3%) were given post-operative radiotherapy and 1 patient underwent revision surgery. A total of 53 patients (61.6%) had recurrence, with 16 (18.6%), 20 (23.2%), 8(9.3%) and 9 (10.5%) patients having locoregional, systemic, peritoneal and simultaneous local-systemic relapse. Systemic recurrences were more often detected either by surveillance in an asymptomatic patient (20.1%) while local (13.1%) and peritoneal (13.2%) recurrences were more often symptomatic (p = 0.000). The 2-year overall survival (OS) and disease-free survival (DFS) of the cohort was 82.4% and 74.0%. Median local recurrence-free survival (LRFS) was 10.3 months.

CONCLUSIONS

Patients with a positive pCRM have high local and distal relapse rates. Systemic relapses are more often asymptomatic as compared to peritoneal or locoregional relapse and detected on follow-up surveillance. Hence, identification of such recurrences while still salvageable via an intensive surveillance protocol is desirable.

Percentage of Tumor Invasion at Pretreatment High-Resolution Magnetic Resonance Imaging: Associating With Aggressive and Tumor Response in Chinese T3 Rectal Cancer-Preliminary Results

Purpose

The purpose of the study was to assess the ability of percentage of tumor invasion (PTI) of T3 rectal cancer on pretreatment MRI as an imaging biomarker to reflect aggressiveness and to predict tumor response after neoadjuvant chemoradiation (NCRT) in Chinese population.

Methods

A total of 107 Chinese rectal cancer patients who underwent pretreatment MRI staging as T3 were included. The extramural depth of tumor invasion (EMD), the distance between outer border of muscularis propria (MP) and mesorectal fascia (MRF) we called "thickness of the mesorectum (TM)") at the same slice and direction were measured at pretreatment MRI, and PTI was equal to EMD/TM, was calculated. The EMD and PTI of subgroups based on pretreatment CEA, CA19-9 levels; N category and pathological complete response (pCR) were compared. The parameters, which described tumor invasion, were compared between pCR and non-pCR group. Student t-tests and logistic analysis were applied.

Results

The pretreatment PTI was higher in CEA ≥5.2 ng/ml patients (58.52% ± 27.68%) than in CEA <5.2 ng/ml patients (47.27% ± 24.15%) (p = 0.034). The pretreatment EMD in non-pCR group (7.21 ± 2.85 mm) was higher than in pCR group (6.14 ± 3.56 mm) (p = 0.049). The pretreatment PTI in non-pCR group (57.4% ± 26.4%) was higher than in pCR group (47.3% ± 29.1%) (p = 0.041). Compared with patients with PTI ≥50%, MRF (+), more patients with PTI <50%, MRF (-) showed pCR (OR = 8.44, p = 0.005; OR = 6.32, p = 0.024).

Conclusion

The PTI obtained at pretreatment MRI may serve as an imaging biomarker to reflect tumor aggressiveness and predict which T3 rectal cancer patients may benefit from NCRT in Chinese population.

Surgical site infection after laparoscopic resection of colorectal cancer is associated with compromised long-term oncological outcome

Background

We evaluated the influence of infectious complications, particularly surgical site infection (SSI), on long-term oncological results after elective laparoscopic resection of colorectal cancer.

Methods

A total of 199 patients who underwent laparoscopic elective resection with negative resection margins for stage I–III colorectal cancer were retrospectively examined. The postoperative course was recorded based on hospital records, and cancer relapse was diagnosed based on radiological or pathological findings under a standardized follow-up program. The severity of complications was graded using Clavien-Dindo (CD) classification.

Results

SSI was found in 25 patients (12.6%), with 12 (6.0%) showing anastomotic leak. The postoperative relapse-free survival (RFS) rate was significantly lower in patients with SSI (49.2%) than in patients without SSI (87.2%, P<0.001). Differences in RFS were found after both colectomy and rectal resection (P<0.001 and P<0.001, respectively). RFS did not differ between patients who had major SSI CD (grade III) and those who had minor SSI CD (grades I or II). Multivariate Cox regression analysis identified the occurrence of SSI and pathological stage as independent co-factors for RFS (P<0.001 and P=0.003).

Conclusion

These results suggest that postoperative SSI compromises long-term oncological results after laparoscopic colorectal resection. Further improvements in surgical technique and refinements in perioperative care may improve long-term oncological results.

A modified method for resected specimen processing in rectal cancer: Semi-opened with transverse slicing for measuring of the circumferential resection margin

Circumferential resection margin (CRM) is essential for oncological quality assessment in rectal cancer surgery. CRM represents a surrogate parameter for oncological outcomes and is important for stratifying treatment strategies in Western nations. In Japan, the mesentery is removed for specimen processing in order to extract as many lymph nodes (LNs) as possible; consequently, CRM cannot be measured. Given the diversification of treatment strategies for rectal cancer, the lack of measurement of CRM to assess surgical outcomes is a crucial issue that must be resolved. Therefore, it is necessary to establish a method enabling measurement of CRM while enjoying the advantages of the Japanese method. In the method we developed, the mesentery is removed from the rectum more than 2 cm away from the tumor, and the vicinity of the tumor is circularized. It is necessary to investigate the usefulness of this method prospectively in a multi-center study.

SEOM-GEMCAD-TTD clinical guidelines for localized rectal cancer (2021)

The management of localized rectal cancer requires a multidisciplinary approach to optimize outcomes, reduce morbidity and prevent under or overtreatments. While early stages may obtain benefit of local resections without any additional therapies, locally advanced rectal cancer becomes a challenge defining the better sequential strategy of surgery, radiotherapy and chemotherapy. The latest results of international phase III studies have positioned the total neoadjuvant therapy as a potential new standard of care in high risk rectal cancers, however, the best schedule is still not well defined.

Shrinkage versus fragmentation response in neoadjuvantly treated oesophageal adenocarcinoma: significant prognostic relevance

Aims

No consensus exists on the clinical value of tumour regression grading (TRG) systems for therapy effects of neoadjuvant chemoradiotherapy (nCRT) in oesophageal adenocarcinoma. Existing TRG systems lack standardization and reproducibility, and do not consider the morphological heterogeneity of tumour response. Therefore, we aim to identify morphological tumour regression patterns of oesophageal adenocarcinoma after nCRT and their association with survival.

Methods and results

Patients with oesophageal adenocarcinoma, who underwent nCRT followed by surgery and achieved a partial response to nCRT, were identified from two Dutch upper‐gastrointestinal (GI) centres (2005–18; test cohort). Resection specimens were scored for regression patterns by two independent observers according to a pre‐defined three‐step flowchart. The results were validated in an external cohort (2001–17). In total, 110 patients were included in the test cohort and 115 in the validation cohort. In the test cohort, two major regression patterns were identified: fragmentation (60%) and shrinkage (40%), with an excellent interobserver agreement (κ = 0.87). Here, patients with a fragmented pattern had a significantly higher pathological stage (stages III/IV: 52 versus 16%; P < 0.001), less downstaging (48 versus 91%; P < 0.001), a higher risk of recurrence [risk ratio (RR) = 2.9, 95% confidence interval (CI) = 1.5–5.6] and poorer 5‐year overall survival (30 versus 80% respectively, P = 0.001).

Conclusions

The validation cohort confirmed these findings, although had more advanced cases (case‐stages = III/IV 91 versus 73%, P = 0.005) and a higher prevalence of fragmented‐pattern cases (80 versus 60%, P = 0.002). When combining the cohorts in multivariate analysis, the pattern of response was an independent prognostic factor [hazard ratio (HR) = 1.76, 95% CI = 1.0–3.0]. In conclusion, we established an externally validated, reproducible and clinically relevant classification of tumour response.

Development and Validation of the Optimal Circumferential Resection Margin in Pathological T3 Esophageal Cancer: A Multicenter, Retrospective Study

BACKGROUND

The clinical significance of circumferential resection margin (CRM) in esophageal squamous cell carcinoma (ESCC) remains unclear. Optimal CRM for predicting the recurrence of pathological T3 ESCC was investigated.

METHODS

Seventy-three patients were retrospectively investigated in the development cohort. Patients were divided into CRM-negative and CRM-positive groups, and clinicopathological factors and survival outcomes were compared between the groups. The cutoff value was validated in another validation cohort (n = 99).

RESULTS

Receiver operating characteristic analysis in the development cohort showed the cutoff value of CRM was 600 μm. In the validation cohort, patients in the CRM-positive group showed a significantly higher rate of locoregional recurrence (p = 0.006) and worse recurrence-free survival (RFS) (p < 0.001) than those in the CRM-negative group. Multivariate analysis identified positive CRM as an independent predictive factor for poor RFS (hazard ratio, 2.695; 95% confidence interval, 1.492-4.867; p = 0.001). The predictive value of our criteria of positive CRM for RFS was higher than that of the Royal College of Pathologists (RCP) and the College of American Pathologists (CAP) criteria. Stratified analysis in the neoadjuvant chemotherapy groups also revealed that the rate of locoregional recurrence was higher in the CRM-positive group than in the CRM-negative group both in the pathological N0 and N1-3 subgroups.

CONCLUSIONS

CRM of 600 μm can be the optimal cutoff value rather than the RCP and CAP criteria for predicting locoregional recurrence after esophagectomy. These results may support the impact of perioperative locoregional control of locally advanced ESCC.

MRI for Rectal Cancer: Staging, mrCRM, EMVI, Lymph Node Staging and Post-Treatment Response

Rectal cancer is a relatively common malignancy in the United States. Magnetic resonance imaging (MRI) of rectal cancer has evolved tremendously in recent years, and has become a key component of baseline staging and treatment planning. In addition to assessing the primary tumor and locoregional lymph nodes, rectal MRI can be used to help with risk stratification by identifying high-risk features such as extramural vascular invasion and can assess treatment response for patients receiving neoadjuvant therapy. As the practice of rectal MRI continues to expand further into academic centers and private practices, standard MRI protocols, and reporting are critical. In addition, it is imperative that the radiologists reading these cases work closely with surgeons, medical oncologists, radiation oncologists, and pathologists to ensure we are providing the best possible care to patients. This review aims to provide a broad overview of the role of MRI for rectal cancer.

Dataset for Pathology Reporting of Colorectal Cancer: Recommendations From the International Collaboration on Cancer Reporting (ICCR)

OBJECTIVE

The aim of this study to describe a new international dataset for pathology reporting of colorectal cancer surgical specimens, produced under the auspices of the International Collaboration on Cancer Reporting (ICCR).

BACKGROUND

Quality of pathology reporting and mutual understanding between colorectal surgeon, pathologist and oncologist are vital to patient management. Some pathology parameters are prone to variable interpretation, resulting in differing positions adopted by existing national datasets.

METHODS

The ICCR, a global alliance of major pathology institutions with links to international cancer organizations, has developed and ratified a rigorous and efficient process for the development of evidence-based, structured datasets for pathology reporting of common cancers. Here we describe the production of a dataset for colorectal cancer resection specimens by a multidisciplinary panel of internationally recognized experts.

RESULTS

The agreed dataset comprises eighteen core (essential) and seven non-core (recommended) elements identified from a review of current evidence. Areas of contention are addressed, some highly relevant to surgical practice, with the aim of standardizing multidisciplinary discussion. The summation of all core elements is considered to be the minimum reporting standard for individual cases. Commentary is provided, explaining each element's clinical relevance, definitions to be applied where appropriate for the agreed list of value options and the rationale for considering the element as core or non-core.

CONCLUSIONS

This first internationally agreed dataset for colorectal cancer pathology reporting promotes standardization of pathology reporting and enhanced clinicopathological communication. Widespread adoption will facilitate international comparisons, multinational clinical trials and help to improve the management of colorectal cancer globally.

Long-term Outcomes of Minimally Invasive Versus Open Abdominoperineal Resection for Rectal Cancer: A Single Specialized Center Experience

BACKGROUND

Randomized studies have validated laparoscopic proctectomy for the treatment of rectal cancer as noninferior to an open proctectomy, but most of those studies have included sphincter-preserving resections along with abdominoperineal resection.

OBJECTIVE

This study aimed to compare perioperative and long-term oncological outcomes between minimally invasive and open abdominoperineal resection.

DESIGN

This study is a retrospective analysis of a prospectively maintained database.

SETTINGS

The study was conducted in a single specialized colorectal surgery department.

PATIENTS

All patients who underwent abdominoperineal resection for primary rectal cancer between 2000 and 2016 were included.

MAIN OUTCOME MEASURES

The primary outcomes measured were the perioperative and long-term oncological outcomes.

RESULTS

We included 452 patients, 372 in the open group and 80 in the minimally invasive group, with a median follow-up time of 74 months. There were significant differences between the groups in terms of neoadjuvant radiation treatment (67.5% of the open versus 81.3% of the minimally invasive group, p = 0.01), operative time (mean of 200 minutes versus 287 minutes, p < 0.0001), and mean length of stay (9.5 days versus 6.6 days, p < 0.0001). Overall complication rates were similar between the groups (34.5% versus 27.5%, p = 0.177). There were no significant differences in the mean number of lymph nodes harvested (21.7 versus 22.2 nodes, p = 0.7), circumferential radial margins (1.48 cm versus 1.37 cm, p = 0.4), or in the rate of involved radial margins (10.8% versus 6.3%, p = 0.37). Five-year overall survival was 70% in the open group versus 80% in the minimally invasive group (p = 0.344), whereas the 5-year disease-free survival rate in the open group was 63.2% versus 77.6% in the minimally invasive group (p = 0.09).

LIMITATIONS

This study was limited because it describes a single referral institution experience.

CONCLUSIONS

Although both approaches have similar perioperative outcomes, the minimally invasive approach benefits the patients with a shorter length of stay and a lower risk for surgical wound infections. Both approaches yield similar oncological technical quality in terms of the lymph nodes harvested and margins status, and they have comparable long-term oncological outcomes. See Video Abstract at http://links.lww.com/DCR/B754.RESULTADOS A LARGO PLAZO DE LA RESECCIÓN ABDOMINOPERINEAL MÍNIMAMENTE INVASIVA VERSUS ABIERTA PARA EL CÁNCER DE RECTO: EXPERIENCIA DE UN SOLO CENTRO ESPECIALIZADOANTECEDENTES:Estudios aleatorizados han validado la proctectomía laparoscópica para el tratamiento del cáncer de recto igual a la proctectomía abierta, pero la mayoría de esos estudios han incluido resecciones con preservación del esfínter junto con resección abdominoperineal.OBJETIVO:Comparar los resultados oncológicos perioperatorios y a largo plazo entre la resección abdominoperineal abierta y mínimamente invasiva.DISEÑO:Análisis retrospectivo de una base de datos mantenida de forma prospectiva.ENTORNO CLINICO:Servicio único especializado en cirugía colorrectal.PACIENTES:Todos los pacientes que se sometieron a resección abdominoperineal por cáncer de recto primario entre 2000 y 2016.PRINCIPALES MEDIDAS DE VALORACION:Resultados oncológicos perioperatorios y a largo plazo.RESULTADOS:Se incluyeron 452 pacientes, 372 en el grupo abierto y 80 en el grupo mínimamente invasivo, con una mediana de seguimiento de 74 meses. Hubo diferencias significativas entre los grupos en términos de tratamiento con radiación neoadyuvante (67,5% del grupo abierto versus 81,3% del grupo mínimamente invasivo, p = 0,01), tiempo operatorio (media de 200 minutos versus 287 minutos, p < 0,0001) y la duración media de la estancia (9,5 días frente a 6,6 días, p < 0,0001). Las tasas generales de complicaciones fueron similares entre los grupos (34,5% versus 27,5%, p = 0,177). No hubo diferencias significativas en el número medio de ganglios linfáticos extraídos (21,7 versus 22,2 ganglios, p = 0,7), márgenes radiales circunferenciales (1,48 cm y 1,37 cm, p = 0,4), ni en la tasa de márgenes radiales afectados (10,8 cm). % versus 6,3%, p = 0,37). La supervivencia general a 5 años fue del 70% en el grupo abierto frente al 80% en el grupo mínimamente invasivo (p = 0,344), mientras que la tasa de supervivencia libre de enfermedad a 5 años en el grupo abierto fue del 63,2% frente al 77,6% en el grupo mínimamente invasivo (p = 0,09).LIMITACIONES:Experiencia en una institución de referencia única.CONCLUSIONES:Si bien ambos tienen resultados perioperatorios similares, el enfoque mínimamente invasivo, beneficia a los pacientes con estadía más corta y menor riesgo de infecciones de la herida quirúrgica. Ambos enfoques, producen una calidad técnica oncológica similar en términos de ganglios linfáticos extraídos y estado de los márgenes, y tienen resultados oncológicos comparables a largo plazo. Consulte Video Resumen en http://links.lww.com/DCR/B754. (Traducción - Dr. Fidel Ruiz Healy).

Early experience with the ARTISENTIAL® articulated instruments in laparoscopic low anterior resection with TME

Background

The notion of articulation in surgery has been largely synonymous with robotics. The ARTISENTIAL^® instruments aim at bringing advanced articulation to laparoscopy to overcome challenges in narrow anatomical spaces. In this paper, we present first single-center results of a series of low anterior resections, performed with ARTISENTIAL^®.

Methods

Between September 2020 and August 2021, at the Department of Surgery, St. Marienkrankenhaus Siegen, Siegen, Germany, patients with cancer of the mid- and low rectum were prospectively enrolled in a pilot feasibility study to evaluate the ARTISENTIAL^® articulated instruments in performing a laparoscopic low anterior resection. Perioperative and short-term postoperative data were analyzed.

Results

Seventeen patients (10 males/7 females) were enrolled in this study. The patients had a median age of 66 years (range 47–80 years) and a median body mass index of 28 kg/m² (range 23–33 kg/m²). The median time to rectal transection was 155 min (range 118–280 min) and the median total operative time was 276 min (range 192–458 min). The median estimated blood loss was 30 ml (range 5–70 ml) and there were no conversions to laparotomy. The median number of harvested lymph nodes was 15 (range 12–28). Total mesorectal excision (TME) quality was ‘good’ in all patients with no cases of circumferential resection margin involvement (R0 = 100%). The median length of stay was 9 days (range 7–14 days). There were no anastomotic leaks and the overall complication rate was 17.6%. There was one unrelated readmission with no mortality.

Conclusions

Low anterior resection with ARTISENTIAL^® is feasible and safe. All patients had a successful TME procedure with a good oncological outcome. We will now seek to evaluate the benefits of ARTISENTIAL^® in comparison with standard laparoscopic instruments through a larger study.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10151-022-02588-y.

Effects of surgical approach on short- and long-term outcomes in early-stage rectal cancer: a multicenter, propensity score-weighted cohort study

BACKGROUND

Randomized controlled trials have been unable to demonstrate noninferiority of minimally invasive surgery for rectal cancer. The aim of this study was to assess oncologic resection success, short- and long-term morbidity, and overall survival by operative approach in a homogenous early-stage rectal cancer cohort.

METHODS

This is a multicenter, propensity score-weighted cohort study utilizing deidentified data from the National Cancer Database. Individuals who underwent a formal proctectomy for early-stage rectal cancer (T1-2, N0, M0) from 2010 to 2015 were included. The primary outcome was a composite variable indicating successful oncologic resection stratified by operative approach, defined as negative margins with at least 12 lymph nodes evaluated.

RESULTS

Among 3649 proctectomies for rectal adenocarcinoma, 1660 (45%) were approached open, 1461 (40%) laparoscopically, and 528 (15%) robotically. After propensity score weighting, compared to open approach, there were no differences in odds of successful oncologic resection (OR_adj = 1.07, 95% CI 0.9, 1.28 and OR_adj = 1.28, 95% CI 0.97, 1.7). Open approach was associated with longer mean (± SD) length of stay compared to laparoscopic (7.7 ± 0.18 vs. 6.5 ± 0.25 days, p < 0.001) and robotic (7.7 ± 0.18 vs. 6.3 ± 0.35 days, p < 0.001) approaches. In regard to 90-day mortality, compared to open approach, laparoscopic (OR_adj = 0.56, 95% CI 0.36, 0.88) and robotic (OR_adj = 0.45, 95% CI 0.22, 0.94) approaches were associated with a reduced odd of 90-day mortality. This mortality benefit persists in the long-term for laparoscopic approach (p = 0.003).

CONCLUSION

For individuals with early-stage rectal cancer treated with proctectomy, successful oncologic resection can be achieved irrespective of technical approach. Minimally invasive approaches provide short-term reduction in morbidity. Surgical approach must be tailored to each patient based on surgeon experience and judgement in collaboration with a multi-disciplinary team.

MRI radiomics features of mesorectal fat can predict response to neoadjuvant chemoradiation therapy and tumor recurrence in patients with locally advanced rectal cancer

OBJECTIVE

To interrogate the mesorectal fat using MRI radiomics feature analysis in order to predict clinical outcomes in patients with locally advanced rectal cancer.

METHODS

This retrospective study included patients who underwent neoadjuvant chemoradiotherapy for locally advanced rectal cancer from 2009 to 2015. Three radiologists independently segmented mesorectal fat on baseline T2-weighted axial MRI. Radiomics features were extracted from segmented volumes and calculated using CERR software, with adaptive synthetic sampling being employed to combat large class imbalances. Outcome variables included pathologic complete response (pCR), local recurrence, distant recurrence, clinical T-category (cT), post-treatment T category (ypT), and post-treatment N category (ypN). A maximum of eight most important features were selected for model development using support vector machines and fivefold cross-validation to predict each outcome parameter via elastic net regularization. Diagnostic metrics of the final models were calculated, including sensitivity, specificity, PPV, NPV, accuracy, and AUC.

RESULTS

The study included 236 patients (54 ± 12 years, 135 men). The AUC, sensitivity, specificity, PPV, NPV, and accuracy for each clinical outcome were as follows: for pCR, 0.89, 78.0%, 85.1%, 52.5%, 94.9%, 83.9%; for local recurrence, 0.79, 68.3%, 80.7%, 46.7%, 91.2%, 78.3%; for distant recurrence, 0.87, 80.0%, 88.4%, 58.3%, 95.6%, 87.0%; for cT, 0.80, 85.8%, 56.5%, 89.1%, 49.1%, 80.1%; for ypN, 0.74, 65.0%, 80.1%, 52.7%, 87.0%, 76.3%; and for ypT, 0.86, 81.3%, 84.2%, 96.4%, 46.4%, 81.8%.

CONCLUSION

Radiomics features of mesorectal fat can predict pathological complete response and local and distant recurrence, as well as post-treatment T and N categories.

KEY POINTS

• Mesorectal fat contains important prognostic information in patients with locally advanced rectal cancer (LARC). • Radiomics features of mesorectal fat were significantly different between those who achieved complete vs incomplete pathologic response (accuracy 83.9%, 95% CI: 78.6-88.4%). • Radiomics features of mesorectal fat were significantly different between those who did vs did not develop local or distant recurrence (accuracy 78.3%, 95% CI: 72.0-83.7% and 87.0%, 95% CI: 81.6-91.2% respectively).

Fluorescence Molecular Targeting of Colon Cancer to Visualize the Invisible

Colorectal cancer (CRC) is a common cause of cancer and cancer-related death. Surgery is the only curative modality. Fluorescence-enhanced visualization of CRC with targeted fluorescent probes that can delineate boundaries and target tumor-specific biomarkers can increase rates of curative resection. Approaches to enhancing visualization of the tumor-to-normal tissue interface are active areas of investigation. Nonspecific dyes are the most-used approach, but tumor-specific targeting agents are progressing in clinical trials. The present narrative review describes the principles of fluorescence targeting of CRC for diagnosis and fluorescence-guided surgery with molecular biomarkers for preclinical or clinical evaluation.

Neoadjuvant chemoradiotherapy for borderline resectable low rectal cancer: short- and long-term outcomes at a single Japanese center

PURPOSE

Rectal cancers pose a threat to the mesorectal fascia or invade neighboring structures or organs. Some tumors are potentially resectable but are likely to be positive at the resection margin for cancer involvement and are thus recognized as "borderline resectable (BR)" tumors. This study aimed to clarify the short- and long-term outcomes of neoadjuvant chemoradiotherapy (nCRT) for BR low rectal cancer at a single Japanese center.

METHODS

Data of 55 patients, who received nCRT followed by BR low rectal cancer surgery between April 2010 and December 2019, were evaluated for the short-term outcomes. The oncological outcomes of 42 patients who underwent surgery between April 2010 and December 2018 were evaluated.

RESULTS

Thirty-six (65.5%) patients had cT4 tumors, and 53 (96.4%) patients had a clinical-stage III or IV. Lateral lymph node dissection was performed in 42 (76.4%) patients. The incidence of severe post-operative complications (Clavien-Dindo grade ≥ III) was 18.2%. Fifty-two (94.5%) patients had a pathological negative resection margin. The 3-year overall survival rate, disease-free survival rate, and cumulative incidence of local recurrence were 100%, 70.3%, and 5.3%, respectively.

CONCLUSION

The short- and long-term outcomes of nCRT for BR low rectal cancer were acceptable. In particular, reasonable local control was achieved.

Current status and role of robotic approach in patients with low-lying rectal cancer

Utilization of robotic surgical systems has increased over the years. Robotic surgery is presumed to have advantages of enhanced visualization, improved dexterity, and reduced tremor, which is purported to be more suitable for rectal cancer surgery in a confined space than laparoscopic or open surgery. However, evidence supporting improved clinical and oncologic outcomes after robotic surgery remains controversial and limited despite the widespread adoption of robotic surgical systems. To date, numerous observational studies and a few randomized controlled trials have failed to demonstrate that short-term, oncological, and functional outcomes after a robotic surgery are superior to those of laparoscopic surgery for low rectal cancer patients. The objective of this review is to summarize the current state of robotic surgery and its impact on low-lying rectal cancer.

Selection of patients with rectal cancer for neoadjuvant therapy using pre-therapeutic MRI - Results from OCUM trial

PURPOSE

No consensus is available on the appropriate criteria for neoadjuvant chemoradiotherapy selection of patients with rectal cancer. The purpose was to evaluate the accuracy of MRI staging and determine the risk of over- and undertreatment by comparing MRI findings and histopathology.

METHOD

In 609 patients of a multicenter study clinical T- and N categories, clinical stage and minimal distance between the tumor and mesorectal fascia (mrMRF) were determined using MRI and compared with the histopathological categories in resected specimen. Accuracy, sensitivity, specificity, positive predictive, and negative predictive value (NPV) were calculated. Overstaging was defined as the MRI category being higher than the histopathological category. mrMRF and circumferential resection margin (CRM) were judged as tumor free at a minimal distance > 1 mm. The chi-squared test or Fisher's exact test were used. P < 0.05 was considered significant.

RESULTS

The T category was correct in 63.5% (386/608) of patients; cT was overstaged in 22.9% (139/608) and understaged in 13.5% (82/608). MRI accuracy for lymph node involvement was 56.5% (344/609); 22.2% (28/126) of patients with clinical stage II and 28.1% (89/317) with clinical stage III disease were diagnosed by histopathology as stage I. The accuracy for tumor free CRM was 86.5% (527/609) and the NPV was 98.1% (514/524). In 1.7% (9/524) mrMRF was false negative.

CONCLUSION

MRI prediction of the tumor-free margin is more reliable than the prediction of tumor stage. MRF status as determined MRI should therefore be prioritized for decision making.

Robotic Versus Laparoscopic Surgery for Rectal Cancer: A Comprehensive Review of Oncological Outcomes

The treatment of rectal cancer is complex and involves specialized multidisciplinary care, although the tenet is still rooted in a high-quality total mesorectal excision. The robotic platform is one of many tools in the arsenal to assist dissection in the low pelvis. This article is a comprehensive review of the oncological outcome comparing robotic vs laparoscopic rectal cancer resection, with a particular focus on total mesorectal excision. There is no statistical difference in total mesorectal grade, circumferential margin, distal margin, and lymph node harvest. Survival data are less mature, but there is also no difference in disease-free or overall survival between the two techniques. Although additional randomized trials are still needed to validate these findings, both techniques are currently acceptable in the minimally invasive treatment of rectal cancer, and surgeon preference is paramount to safe and optimal resection.

Pathological Features and Prognostication in Colorectal Cancer

The prognostication of colorectal cancer (CRC) has traditionally relied on staging as defined by the Union for International Cancer Control (UICC) and American Joint Committee on Cancer (AJCC) TNM staging classifications. However, clinically, there appears to be differences in survival patterns independent of stage, suggesting a complex interaction of stage, pathological features, and biomarkers playing a role in guiding prognosis, risk stratification, and guiding neoadjuvant and adjuvant therapies. Histological features such as tumour budding, perineural invasion, apical lymph node involvement, lymph node yield, lymph node ratio, and molecular features such as MSI, KRAS, BRAF, and CDX2 may assist in prognostication and optimising adjuvant treatment. This study provides a comprehensive review of the pathological features and biomarkers that are important in the prognostication and treatment of CRC. We review the importance of pathological features and biomarkers that may be important in colorectal cancer based on the current evidence in the literature.

Quality Indicators of Transanal Total Mesorectal Excision (TaTME) for Rectal Cancer

Introduction Transanal total mesorectal excision (TaTME) has revolutionized the surgical techniques for lower-third rectal cancer. The aim of the present study was to analyze the outcomes of quality indicators of TaTME for rectal cancer compared with laparoscopic TME (LaTME).

Methods A cohort prospective study with 50 (14 female and 36 male) patients, with a mean age of 67 (range: 55.75 to 75.25) years, who underwent surgery for rectal cancer. In total, 20 patients underwent TaTME, and 30, LaTME. Every TaTME procedure was performed by experienced colorectal surgeons. The sample was divided into two groups (TaTME and LaTME), and the quality indicators of the surgery for rectal cancer were analyzed.

Results There were no statistically significant differences regarding the patients and the main characteristics of the tumor (age, gender, American Society of Anesthesiologists [ASA] score, body mass index [BMI], tumoral stage, neoadjuvant therapy, and distance from the tumor to the external anal margin) between the two groups. The rates of: postoperative morbidity (TaTME: 35%; LaTME: 30%; p = 0.763); mortality (0%); anastomotic leak (TaTME: 10%; LaTME: 13%; p = 0.722); wound infection (TaTME: 0%; LaTME: 3.3%; p = 0.409); reoperation (TaTME: 5%; LaTME: 6.6%; p = 0.808); and readmission (TaTME: 5%; LaTME: 0%; p = 0.400), as well as the length of the hospital stay (TaTME: 13.5 days; LaTME: 11 days; p = 0.538), were similar in both groups. There were no statistically significant differences in the rates of positive circumferential resection margin (TaTME: 5%; LaTME: 3.3%; p = 0.989) and positive distal resection margin (TaTME: 0%; LaTME: 3.3%; p = 0.400), the completeness of the TME (TaTME: 100%; LaTME: 100%), and the number of lymph nodes harvested (TaTME: 15; LaTME: 15.5; p = 0.882) between two groups.

Conclusion Transanal total mesorectal excision is a safe and feasible surgical procedure for middle/lower-third rectal cancer.

A new prognostic risk model based on autophagy-related genes in kidney renal clear cell carcinoma

This study aimed to explore the potential role of autophagy-related genes in kidney renal clear cell carcinoma (KIRC) and develop a new prognostic-related risk model. In our research, we used multiple bioinformatics methods to perform a pan-cancer analysis of the CNV, SNV, mRNA expression, and overall survival of autophagy-related genes, and displayed the results in the form of heat maps. We then performed cluster analysis and LASSO regression analysis on these autophagy-related genes in KIRC. In the cluster analysis, we successfully divided patients with KIRC into five clusters and found that there was a clear correlation between the classification and two clinicopathological features: tumor, and stage. In LASSO regression analysis, we used 13 genes to create a new prognostic-related risk model in KIRC. The model showed that the survival rate of patients with KIRC in the high-risk group was significantly lower than that in the low-risk group, and that there was a correlation between this grouping and the patients' metastasis, tumor, stage, grade, and fustat. The results of the ROC curve suggested that this model has good prediction accuracy. The results of multivariate Cox analysis show that the risk score of this model can be used as an independent risk factor for patients with KIRC. In summary, we believe that this research provides valuable data supporting future clinical treatment and scientific research.

Comparison of oncologic outcome of abdominoperineal resection versus sphincter saving resection for low lying rectal cancer

Purpose

The present study compares the peri/postoperative and oncological outcomes of abdominoperineal resections (APR) and sphincter saving resection (SSR) for low lying rectal cancer.

Methods

Between January 2001 and December 2014, 176 patients who underwent SSR (n=67) and APR (n=109) for low rectal cancer, without stage IV, were retrieved from a retrospective database.

Results

With a median follow-up of 66.5 months. The mean total number of harvested lymph nodes was 16.7 (SSR) versus 17.1 (APR) (P=0.801). The advanced T stage was higher in the APR group (82.6%) versus the SSR group (55.2%) (P=0.006). The positive rate of lymph nodes after surgery was significantly higher in the APR group (45.9%) versus SSR group (25.4%) (P<0.05). The 5-year overall survival rates for SSR and APR were 87.3% and 67.6%, respectively (P<0.005). The 5-year disease-free survival rate (DFS) was 83.6% (SSR) versus 65.5% (APR) (P=0.002). The recurrence rate was higher in the APR group (34.9%) versus the SSR group (14.9%) (P=0.004). Local recurrence rate was not different between the two groups. However, distant recurrence rate was significantly higher in the APR group (26.6% vs. 11.9%, P=0.023). In multivariate analysis, node positive (N0 vs. N1-2) was an independent prognostic factor for DFS (P<0.005).

Conclusion

Based on the present data, SSR achieved better 5-year oncological outcome than APR. The positive lymph node ratio in the N stage after surgery was higher in the APR group and this seems to have an effect on the oncological outcomes of the APR group.

Fluorescence ureteral navigation during laparoscopic surgery for clinically suspected stage T4 colorectal cancer: A cohort study

BACKGROUND

Approximately 15% of patients with colorectal cancer present with locally advanced tumors (T4 stage). Laparoscopic surgery for stage T4 disease has not yet been established. The near-infrared ray catheter fluorescent ureteral catheter (NIRFUC) is a new device that uses near-infrared fluorescence resin. We examined the utility of fluorescence ureteral navigation (FUN) with the NIRFUC during laparoscopic surgery for stage T4 colorectal cancer.

MATERIALS AND METHODS

Patients with stage T4 colorectal cancer (n = 143, from January 2017 to March 2021) were divided into a T4FUN + group, in which the NIRFUC was used (n = 21), and a T4FUN- group, in which the NIRFUC was not used (n = 122). Short-term outcomes were compared between the groups. Next, the laparoscopic surgery rate and incidence of ureteral injury from January 2017 to March 2021 were compared between the T4FUN- group and the non-stage T4FUN- group (n = 434, from January 2017 to March 2021), in which fluorescence ureter navigation was not used.

RESULTS

Rectal cancer, stage T4b disease, and invasion into the urinary tract were observed more often in the T4FUN + group than in the T4FUN- group. In the comparisons of the T4FUN + versus T4FUN- groups, the operative time was 398 (161-1090) vs. 256 (93-839) minutes, the blood loss was 10 (1-710) vs. 25 (0-1360) ml, and the ratio of laparoscopic surgery to open surgery was 21:0 vs. 79:43. Postoperative complications (Clavien-Dindo grade ≥ III) were present in 2 (10%; 0 ureteral injury) patients in the T4FUN + group and 13 (11%; 2 ureteral injury) patients in the T4FUN- group. In the T4FUN + group, the operative time was longer (p < 0.0001), but the laparoscopic ratio was higher (p = 0.0002), and the blood loss volume and incidence of ureteral injury tended to be lower. In the comparisons of the T4FUN- versus non-stage T4FUN- groups, the ratio of laparoscopic surgery to open surgery was 79:43 vs. 384:50, the incidence of open conversion was 8 (6.6%) vs. 15 (3.5%), and the incidence of ureteral injury was 2 (1.6%) vs. 0 (0%). In the T4FUN- group, the open surgery rate (<0.0001), open conversion rate (p = 0.0205) and incidence of ureteral injury (p = 0.0478) were high, with a significant difference observed between the groups.

CONCLUSION

Patients with stage T4 disease have an increased risk of ureteral injury and are more likely to be converted to open surgery. FUN can help to safely increase the laparoscopic surgery rate while safely visualizing the ureter. FUN is recommended for laparoscopic surgery in patients with stage T4 colorectal cancer.

CLINICAL TRIAL REGISTRATION

Examination of fluorescence navigation for laparoscopic colorectal cancer surgery; Research Ethics Committee of the Kawaguchi Municipal Medical Center (Saitama, Japan) approval number: 2020-3. https://kawaguchi-mmc.org/wp-content/uploads/clinical research-r02.pdf.

Multimodal Treatment of cT3 Rectal Cancer in a Prospective Multi-Center Observational Study: Can Neoadjuvant Chemoradiation Be Omitted in Patients with an MRI-Assessed, Negative Circumferential Resection Margin?

Background/Aim

Neoadjuvant chemoradiation (nCRT) in rectal cancer is associated with significant long-term morbidity. It is unclear whether nCRT in resectable mesorectal fascia circumferential resection margin (mrCRM)-negative rectal cancer treated by adequate total mesorectal excision (TME) is beneficial. The aim was to determine if nCRT can be omitted in patients with MRI-assessed cT3 rectal cancer and a negative mrCRM undergoing good-quality TME.

Methods

By means of a prospective nationwide registry (n = 43.147; prospective multi-center observational study), patients with cT3 rectal cancer <12 cm from the anal verge with a negative (>1 mm) MRI-assessed CRM undergoing radical resection from 2006 to 2008 were selected. Overall, 87 patients were available for the final analysis (TME-alone, n = 25; nCRT+TME, n = 62). Groups were balanced for age, sex, and ASA score, with a nonsignificant predominance of males in the nCRT+TME group. As main outcome measures, local and distant recurrence rates were compared between patients undergoing primary surgery (TME-alone) vs. neoadjuvant chemoradiation + surgery (nCRT+TME).

Results

In the TME-alone group, tumors were located closer to the anal verge (p = 0.018) and demonstrated a smaller minimal circumferential distance from the resection margin (p = 0.036). TME quality was comparable, as was median follow-up (48.9 vs. 44.9 months; p = 0.268). Local recurrences occurred at a similar rate in the TME-alone (n = 1; 5.3%) and nCRT+TME groups (n = 3; 5.5%) (p = 0.994) and were diagnosed at 10 months (TME-alone) and at 8, 13, and 18 months (nCRT+TME). Distant recurrences occurred in 28.9 and 17.4% of the cases, respectively (p = 0.626). The analysis was limited to cT3 cancers with a negative mrCRM. In addition, caution is required when appraising these results because of the limited number of evaluable subjects (especially in the TME-alone group), which adds some uncertainty to the statistical analysis.

Conclusions

In this cohort of patients with rectal cancer located <12 cm from the anal verge and a negative mrCRM undergoing adequate TME, omission of nCRT had no impact onto the local recurrence rate.

Is elective inguinal or external iliac irradiation during neoadjuvant (chemo)radiotherapy necessary for locally advanced lower rectal cancer with anal sphincter invasion?

PURPOSE

To investigate the impact of excluding irradiation of inguinal lymph nodes (ILNs) and external iliac lymph nodes (ELNs) during neoadjuvant (chemo)radiotherapy in a locally advanced lower rectal cancer (LALRC) with anal sphincter invasion.

MATERIALS AND METHODS

A total of 214 LALRC patients with anal sphincter invasion according to pre-treatment magnetic resonance imaging who underwent neoadjuvant (chemo)radiotherapy followed by surgery between September 2010 and May 2019 were enrolled. ILNs and ELNs were clinically negative pre-treatment and were excluded from irradiation. Failure rates and patterns of ILNs and ELNs and survival were analyzed. Nomograms for predicting ILN and ELN failure risk were also constructed.

RESULTS

The median follow-up was 53.3 months. The three-year failure rates were 3.7% for ILNs and 3.3% for ELNs. Only one patient developed isolated ILN failure, and no patient experienced isolated ELN failure. Multivariate analyses demonstrated that lower edge of tumors invaded or located below the dentate line (odds ratio [OR] 7.513, P = 0.013), high histological grade (OR 6.892, P = 0.017), and perineural invasion (OR 7.111, P = 0.023) were significantly related to ILN failure. Both perineural invasion (OR 8.923, P = 0.011) and high histological grade (OR 8.129, P = 0.011) showed a strong correlation with ELN failure. The concordance index of nomograms for predicting ILN and ELN failure risk were 0.842 and 0.880, respectively. The three-year local recurrence free survival, disease-free survival, and overall survival were 94.6% (95% confidence interval [CI], 91.3%‒97.9%), 77.7% (95% CI, 71.8%‒83.6%), and 91.9% (95% CI, 87.8%‒96.0%), respectively, for the whole cohort.

CONCLUSIONS

Excluding ILNs and ELNs from irradiation was associated with an acceptably low failure risk for LALRC invading the anal sphincter. These findings help to refine existing guidelines for clinical target volume delineation of ILNs and ELNs during neoadjuvant (chemo)radiotherapy in rectal cancer.

Clinical Complete Response in Patients With Rectal Adenocarcinoma Treated With Short-Course Radiation Therapy and Nonoperative Management

PURPOSE

This study aimed to determine the clinical efficacy and safety of nonoperative management (NOM) for patients with rectal cancer with a clinical complete response (cCR) after short-course radiation therapy and consolidation chemotherapy.

METHODS AND MATERIALS

Patients with stage I-III rectal adenocarcinoma underwent short-course radiation therapy followed by consolidation chemotherapy between January 2018 and May 2019 (n = 90). Clinical response was assessed by digital rectal examination, pelvic magnetic resonance imaging, and endoscopy. Of the patients with an evaluable initial response, those with a cCR (n = 43) underwent NOM, and those with a non-cCR (n = 43) underwent surgery. The clinical endpoints included local regrowth-free survival, regional control, distant metastasis-free survival, disease-free survival, and overall survival.

RESULTS

Compared with patients with an initial cCR, patients with initial non-cCR had more advanced T and N stage (P = .05), larger primary tumors (P = .002), and more circumferential resection margin involvement on diagnostic magnetic resonance imaging (P < .001). With a median follow-up of 30.1 months, the persistent cCR rate was 79% (30 of 38 patients) in the NOM cohort. The 2-year local regrowth-free survival was 81% (95% confidence interval [CI], 70%-94%) in the initial cCR group, and all patients with local regrowth were successfully salvaged. Compared with those with a non-cCR, patients with a cCR had improved 2-year regional control (98% [95% CI, 93%-100%] vs 85% [95% CI, 74%-97%], P = .02), distant metastasis-free survival (100% [95% CI, 100%-100%] vs 80% [95% CI, 69%-94%], P < .01), disease-free survival (98% [95% CI, 93%-100%] vs 71% [95% CI, 59%-87%], P < .01), and overall survival (100% [95% CI, 100%-100%] vs 88% [95% CI, 79%-98%], P = .02). No late grade 3+ gastrointestinal or genitourinary toxicities were observed in the patients who underwent continued NOM.

CONCLUSIONS

Short-course radiation therapy followed by consolidation chemotherapy may be a feasible organ preservation strategy in rectal cancer. Additional prospective studies are necessary to evaluate the safety and efficacy of this approach.

Fluorescence-guided surgery in colorectal cancer; A review on clinical results and future perspectives

BACKGROUND

Colorectal cancer is the fourth most diagnosed malignancy worldwide and surgery is one of the cornerstones of the treatment strategy. Near-infrared (NIR) fluorescence imaging is a new and upcoming technique, which uses an NIR fluorescent agent combined with a specialised camera that can detect light in the NIR range. It aims for more precise surgery with improved oncological outcomes and a reduction in complications by improving discrimination between different structures.

METHODS

A systematic search was conducted in the Embase, Medline and Cochrane databases with search terms corresponding to 'fluorescence-guided surgery', 'colorectal surgery', and 'colorectal cancer' to identify all relevant trials.

RESULTS

The following clinical applications of fluorescence guided surgery for colorectal cancer were identified and discussed: (1) tumour imaging, (2) sentinel lymph node imaging, (3) imaging of distant metastases, (4) imaging of vital structures, (5) imaging of perfusion. Both experimental and FDA/EMA approved fluorescent agents are debated. Furthermore, promising future modalities are discussed.

CONCLUSION

Fluorescence-guided surgery for colorectal cancer is a rapidly evolving field. The first studies show additional value of this technique regarding change in surgical management. Future trials should focus on patient related outcomes such as complication rates, disease free survival, and overall survival.

Brazilian society of surgical oncology: Guidelines for the surgical treatment of mid-low rectal cancer

BACKGROUND

Colorectal cancer (CRC) is the third leading cause of cancer in North America, Western Europe, and Brazil, and represents an important public health problem. It is estimated that approximately 30% of all the CRC cases correspond to tumors located in the rectum, requiring complex multidisciplinary treatment. In an effort to provide surgeons who treat rectal cancer with the most current information based on the best evidence in the literature, the Brazilian Society of Surgical Oncology (SBCO) has produced the present guidelines for rectal cancer treatment that is focused on the main topics related to daily clinical practice.

OBJECTIVES

The SBCO developed the present guidelines to provide recommendations on the main topics related to the treatment of mid-low rectal cancer based on current scientific evidence.

METHODS

Between May and June 2021, 11 experts in CRC surgery met to develop the guidelines for the treatment of mid-low rectal cancer. A total of 22 relevant topics were disseminated among the participants. The methodological quality of a final list with 221 sources was evaluated, all the evidence was examined and revised, and the treatment guideline was formulated by the 11-expert committee. To reach a final consensus, all the topics were reviewed via a videoconference meeting that was attended by all 11 of the experts.

RESULTS

The prepared guidelines contained 22 topics considered to be highly relevant in the treatment of mid-low rectal cancer, covering subjects related to the tests required for staging, surgical technique-related aspects, recommended measures to reduce surgical complications, neoadjuvant strategies, and nonoperative treatments. In addition, a checklist was proposed to summarize the important information and offer an updated tool to assist surgeons who treat rectal cancer provide the best care to their patients.

CONCLUSION

These guidelines summarize concisely the recommendations based on the most current scientific evidence on the most relevant aspects of the treatment of mid-low rectal cancer and are a practical guide that can help surgeons who treat rectal cancer make the best therapeutic decision.

Anus-Preserving Surgery in Advanced Low-Lying Rectal Cancer: A Perspective on Oncological Safety of Intersphincteric Resection

The surgical management of low-lying rectal cancer, within 5 cm from the anal verge (AV), is challenging due to the possibility, or not, to preserve the anus with its sphincter muscles maintaining oncological safety. The standardization of total mesorectal excision, the adoption of neoadjuvant chemoradiotherapy, the implementation of rectal magnetic resonance imaging, and the evolution of mechanical staplers have increased the rate of anus-preserving surgeries. Moreover, extensive anatomy and physiology studies have increased the understanding of the complexity of the deep pelvis. Intersphincteric resection (ISR) was introduced nearly three decades ago as the ultimate anus-preserving surgery. The definition and indication of ISR have changed over time. The adoption of the robotic platform provides excellent perioperative results with no differences in oncological outcomes. Pushing the boundaries of anus-preserving surgeries has risen doubts on oncological safety in order to preserve function. This review critically discusses the oncological safety of ISR by evaluating the anatomical characteristics of the deep pelvis, the clinical indications, the role of distal and circumferential resection margins, the role of the neoadjuvant chemoradiotherapy, the outcomes between surgical approaches (open, laparoscopic, and robotic), the comparison with abdominoperineal resection, the risk factors for oncological outcomes and local recurrence, the patterns of local recurrences after ISR, considerations on functional outcomes after ISR, and learning curve and surgical education on ISR.

Update on Robotic Total Mesorectal Excision for Rectal Cancer

The minimally invasive treatment of rectal cancer with Total Mesorectal Excision is a complex and challenging procedure due to technical and anatomical issues which could impair postoperative, oncological and functional outcomes, especially in a defined subgroup of patients. The results from recent randomized controlled trials comparing laparoscopic versus open surgery are still conflicting and trans-anal bottom-up approaches have recently been developed. Robotic surgery represents the latest consistent innovation in the field of minimally invasive surgery that may potentially overcome the technical limitations of conventional laparoscopy thanks to an enhanced dexterity, especially in deep narrow operative fields such as the pelvis. Results from population-based multicenter studies have shown the potential advantages of robotic surgery when compared to its laparoscopic counterpart in terms of reduced conversions, complication rates and length of stay. Costs, often advocated as one of the main drawbacks of robotic surgery, should be thoroughly evaluated including both the direct and indirect costs, with the latter having the potential of counterbalancing the excess of expenditure directly related to the purchase and maintenance of robotic equipment. Further prospectively maintained or randomized data are still required to better delineate the advantages of the robotic platform, especially in the subset of most complex and technically challenging patients from both an anatomical and oncological standpoint.

Predictors of Positive Circumferential Resection Margin in Rectal Cancer: A Current Audit of the National Cancer Database

BACKGROUND

Positive circumferential resection margin is a predictor of local recurrence and worse survival in rectal cancer. National programs aimed to improve rectal cancer outcomes were first created in 2011 and continue to evolve. The impact on circumferential resection margin during this time frame has not been fully evaluated in the United States.

OBJECTIVE

The purpose of this study was to determine the incidence and predictors of positive circumferential resection margin after rectal cancer resection, across patient, provider, and tumor characteristics.

DESIGN

This was a retrospective cohort study.

SETTINGS

The study was conducted using the National Cancer Database, 2011-2016.

PATIENTS

Adults who underwent proctectomy for pathologic stage I to III rectal adenocarcinoma were included.

MAIN OUTCOME MEASURES

Rate and predictors of positive circumferential resection margin, defined as resection margin ≤1 mm, were measured.

RESULTS

Of 52,620 cases, circumferential resection margin status was reported in 90% (n = 47,331) and positive in 18.4% (n = 8719). Unadjusted analysis showed that patients with positive circumferential resection margin were more often men, had public insurance and shorter travel, underwent total proctectomy via open and robotic approaches, and were treated in Southern and Western regions at integrated cancer networks (all p < 0.001). Multivariate analysis noted that positive proximal and/or distal margin on resected specimen had the strongest association with positive circumferential resection margin (OR = 15.6 (95% CI, 13.6-18.1); p < 0.001). Perineural invasion, total proctectomy, robotic approach, neoadjuvant chemoradiation, integrated cancer network, advanced tumor size and grade, and Black race had increased risk of positive circumferential resection margin (all p < 0.050). Laparoscopic approach, surgery in North, South, and Midwest regions, greater hospital volume and travel distance, lower T-stage, and higher income were associated with decreased risk (all p < 0.028).

LIMITATIONS

This was a retrospective cohort study with limited variables available for analysis.

CONCLUSIONS

Despite creation of national initiatives, positive circumferential resection margin rate remains an alarming 18.4%. The persistently high rate with predictors of positive circumferential resection margin identified calls for additional education, targeted quality improvement assessments, and publicized auditing to improve rectal cancer care in the United States. See Video Abstract at http://links.lww.com/DCR/B584.

PREDICTORES PARA UN MARGEN POSITIVO DE RESECCIN CIRCUNFERENCIAL EN EL CNCER DE RECTO UNA AUDITORA VIGENTE DE LA BASE DE DATOS NACIONAL DE CANCER

ANTECEDENTES:El margen positivo de resección circunferencial es un predictor de recurrencia local y peor sobrevida en el cáncer de recto. Los programas nacionales destinados a mejorar los resultados del cáncer de recto se crearon por primera vez en 2011 y continúan evolucionando. La repercusión del margen de resección circunferencial durante este período de tiempo no se ha evaluado completamente en los Estados Unidos.OBJETIVO:Determinar la incidencia y los predictores para un margen positivo de resección circunferencial posterior a la resección del cáncer de recto, según las características del paciente, el proveedor y el tumor.DISEÑO:Estudio de cohorte retrospectivo.AMBITO:Base de datos nacional de cáncer, 2011-2016.PACIENTES:Adultos que se sometieron a proctectomía por adenocarcinoma de recto con un estadío por patología I-III.PRINCIPALES VARIABLES EVALUADAS:Tasa y predictores para un margen positivo de resección circunferencial, definido como margen de resección ≤ 1 mm.RESULTADOS:De 52,620 casos, la condición del margen de resección circunferencial se informó en el 90% (n = 47,331) y positivo en el 18.4% (n = 8,719). El análisis no ajustado mostró que los pacientes con margen positivo de resección circunferencial se presentó con mayor frecuencia en hombres, tenían un seguro social y viajes más cortos, se operaron de proctectomía total abierta y robótica, y fueron tratados en las regiones del sur y el oeste en redes integradas de cáncer (todos p <0,001). El análisis multivariado destacó que el margen proximal y / o distal positivo de la pieza resecada tenía la asociación más fuerte con el margen postivo de resección circunferencial (OR 15,6; IC del 95%: 13,6-18,1, p <0,001). La invasión perineural, la proctectomía total, el abordaje robótico, la quimioradioterapia neoadyuvante, la red de cáncer integrada, el tamaño y grado del tumor avanzado y la raza afroamericana tenían un mayor riesgo de un margen de una resección positiva circunferencial (todos p <0,050). El abordaje laparoscópico, la cirugía en las regiones Norte, Sur y Medio Oeste, un mayor volumen hospitalario y distancia de viaje, estadio T más bajo y mayores ingresos se asociaron con una disminución del riesgo (todos p <0,028).LIMITACIONES:Estudio de cohorte retrospectivo con variables limitadas disponibles para análisis.CONCLUSIONES:A pesar del establecimiento de iniciativas nacionales, la tasa de margen positivo de resección circunferencial continúa siendo alarmante, 18,4%. El índice continuamente elevado junto a los predictores de un margen positivo de resección circunferencial hace un llamado para una mayor educación, evaluaciones específicas de mejora de la calidad y difusión de las auditorías para mejorar la atención del cáncer de recto en los Estados Unidos. Vea el resumen de video en http://links.lww.com/DCR/B584. Consulte Video Resumen en http://links.lww.com/DCR/B584.

Poor response at restaging MRI and high incomplete resection rates of locally advanced mucinous rectal cancer after chemoradiation therapy

AIM

Mucinous carcinoma is a histological subtype of rectal cancer and has been associated with a poor response to neoadjuvant chemoradiotherapy (CRT). The primary aim of this study was to analyse the response on MRI of mucinous locally advanced rectal cancer (LARC) after CRT compared to regular adenocarcinoma.

METHOD

Patients with LARC (defined as cT4 and/or cN2), who underwent CRT followed by restaging MRI and surgery in two tertiary referral hospitals were retrospectively included in the study. Pre- and post-treatment MRI was reviewed by an experienced abdominal radiologist.

RESULTS

A total of 102 patients, of whom 29 were diagnosed with mucinous carcinoma, were included for analysis. At restaging MRI, adenocarcinoma patients demonstrated significantly less clinical involvement of the mesorectal fascia (37% vs. 62%, P = 0.003) while this was not demonstrated in mucinous carcinoma patients (86% vs. 97%, P = 0.16). Significant downstaging after CRT in adenocarcinoma patients (P = 0.01) was seen while, in mucinous carcinoma patients, no downstaging after CRT (P = 0.89) was seen. Pathology revealed significantly higher rates of an involved circumferential resection margin in mucinous carcinoma versus adenocarcinoma patients (27.6% vs. 1.4%; P < 0.001). After multivariate regression analysis, mucinous carcinoma remained an independent prognostic factor for local recurrence (hazard ratio 3.6; 95% CI 1.1-12.4), although no differences in overall or disease-free survival were observed.

CONCLUSION

Mucinous rectal carcinoma is associated with a poor clinical response at restaging MRI after CRT, leading to relatively higher rates of involved circumferential resection margins at pathology. In this cohort, mucinous carcinoma seems to be a prognostic factor for increased risk of local recurrence, without an effect on overall survival.

Association of Adherence to Quality Metrics with Recurrence or Mortality among Veterans with Colorectal Cancer

BACKGROUND

The National Comprehensive Cancer Network has defined metrics for colorectal cancer; however, the association of metric adherence with patient clinical outcomes remains underexplored. The study aim was to evaluate the association of National Comprehensive Cancer Network metric adherence with recurrence and mortality in Veterans with nonmetastatic colorectal cancer.

METHODS

Veterans with stage I-III colorectal cancer who underwent non-emergent resection from 2001 to 2015 at a single Veterans Affairs Medical Center were included. The primary predictor was completion of eligible National Comprehensive Cancer Network metrics. The primary outcome was a composite of recurrence or all-cause death in three phases of care: surgical (up to 6 months after resection), treatment (6-18 months after resection), and surveillance (18 months-3 years after resection). Hazard ratios were estimated via Cox proportional hazards regression in a propensity score-weighted cohort.

RESULTS

A total of 1107 electronic medical records of patients undergoing colorectal surgery were reviewed, and 379 patients were included (301 colon and 78 rectal cancer). In the surgical phase, the weighted analysis yielded a hazard ratio of 0.37 (95% confidence interval 0.12-1.13) for metric-adherent patients compared with non-adherent patients. In the treatment and surveillance phases, the hazard ratios for metric-adherent care were 0.68 (95% confidence interval 0.25-1.85) and 0.91 (95% confidence interval 0.31-2.68), respectively.

CONCLUSIONS

The National Comprehensive Cancer Network guideline metric adherence was associated with a lower rate of recurrence and death in the surgical phase of care among stage I-III patients with resected colorectal cancer.

Therapeutic effects and limitations of chemoradiotherapy in advanced lower rectal cancer focusing on T4b

PURPOSE

This study aimed to elucidate the benefits and limitations of preoperative chemoradiotherapy (CRT) in rectal cancer treatment, specifically in T4b rectal cancer.

METHODS

This retrospective cohort study reviewed 1014 consecutive patients with clinical T3/4a/T4b adenocarcinomas of the lower rectum, who underwent total mesorectal excision at the Department of Surgical Oncology of the University of Tokyo Hospital and 22 referral institutions affiliated with the Japanese Study Group for Postoperative Follow-up of Colorectal Cancer. Patients were divided into two cohorts: cohort 1 comprised 298 consecutive patients who underwent CRT followed by radical surgery and cohort 2 comprised 716 consecutive patients who underwent curative surgery without preoperative therapy. We assessed the prognostic differences between the two cohorts, focusing particularly on T stages.

RESULTS

In T3/4a patients, cohort 1 showed a significantly lower local recurrence rate than cohort 2 (4.8% vs. 9.4%, p=0.024), but not in T4b patients (23.5% vs. 16.0%, p=0.383). In contrast, no significant differences in survival were observed between T3/4a and T4b patients. T4b classification was found to be an independent predictive factor of local recurrence in cohort 1, but not in cohort 2.

CONCLUSION

In T4b rectal cancer, preoperative CRT demonstrated a limited benefit for local control and survival. In cases of suspected T4b rectal tumors, additional therapies such as induction chemotherapy to conventional CRT may contribute to better outcomes.