The utility of preoperative radiological evaluation of early rectal neoplasia: a systematic review and meta-analysis

MRI of early rectal cancer; bisacodyl micro-enema increases submucosal width, reader confidence, and tumor conspicuity

PURPOSE

To investigate the influence of a micro-enema on diagnostic performance, submucosal width, reader confidence, and tumor conspicuity using MRI to stage early rectal cancers (ERC).

METHODS

In this single-center study, we consecutively included 50 participants with assumed ERC who all completed MRI with (MRin) and without (MRex) a micro-enema. The diagnostic performance was recorded for two experienced radiologists using histopathology as the gold standard. In addition, the width of the submucosa in the tumor-bearing wall, reader confidence for T-staging, and tumor conspicuity were assessed. Significance levels were calculated using McNemar's test (diagnostic performance) and Wilcoxon's signed-rank test (reader confidence, submucosal width, and conspicuity). Interreader agreement was assessed using kappa statistics.

RESULTS

Sensitivity/specificity were for Reader1 91%/87% for both MRex and MRin and for Reader2 74%/87% and 89%/87%, both readers p > 0.05. The micro-enema induced a significant widening of the submucosa, p < 0.001, with a mean increase of 2.2/2.8 mm measured by Reader1/Reader2. Reader confidence in T-staging and tumor conspicuity increased for both readers, p < 0.005. The proportion of tumors with both correct staging and high reader confidence increased from 58% (29/50) to 80% (40/50) (p = 0.04) for Reader1 and from 42% (21/50) to 72% (36/50) (p = 0.002) for Reader2. Interreader agreement increased from moderate (kappa 0.58) to good (kappa 0.68).

CONCLUSION

The micro-enema significantly increased the submucosal width in the tumor-bearing wall, reader confidence, and tumor conspicuity and improved interreader agreement from moderate to good. Sensitivity and specificity in T-staging did not improve, but there was a significant increase in the proportion of tumors staged with both high confidence and correct T-stage.

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of colorectal cancer, 2024 update

The 2024 updates of the Chinese Society of Clinical Oncology (CSCO) Clinical Guidelines for the diagnosis and treatment of colorectal cancer emphasize standardizing cancer treatment in China, highlighting the latest advancements in evidence-based medicine, healthcare resource access, and precision medicine in oncology. These updates address disparities in epidemiological trends, clinicopathological characteristics, tumor biology, treatment approaches, and drug selection for colorectal cancer patients across diverse regions and backgrounds. Key revisions include adjustments to evidence levels for intensive treatment strategies, updates to regimens for deficient mismatch repair (dMMR)/ microsatellite instability-high (MSI-H) patients, proficient mismatch repair (pMMR)/ microsatellite stability (MSS) patients who have failed standard therapies, and rectal cancer patients with low recurrence risk. Additionally, recommendations for digital rectal examination and DNA polymerase epsilon (POLE)/ DNA polymerase delta 1 (POLD1) gene mutation testing have been strengthened. The 2024 CSCO Guidelines are based on both Chinese and international clinical research, as well as expert consensus, ensuring their relevance and applicability in clinical practice, while maintaining a commitment to scientific rigor, impartiality, and timely updates.

Risk Factors for Rectal Cancer Recurrence after Local Excision of T1 Lesions from a Decade-Long Multicenter Retrospective Study

Background: Local surgical excision of T1 rectal adenocarcinoma is a well-established approach. Yet, there are still open questions regarding the recurrence rates and its risk factors. Methods: A retrospective multicenter study including all patients who underwent local excision of early rectal cancer with an open or MIS approach and had a T1 lesion from 2010 to 2020 in six academic centers. Data included demographics, preoperative studies, surgical findings, postoperative outcomes, and local and systemic recurrence. A univariable and multivariable logistic regression analysis was performed to identify risk factors for recurrence. Results: Overall, 274 patients underwent local excision of rectal lesions. Of them, 97 (35.4%) patients with a T1 lesion were included in the cohort. The mean age was 69 ± 10.5 years, and 42 (43.3%) were female. The mean distance of the lesions from the anal verge was 7.8 ± 3.2 cm, and the average tumor size was 2.7 ± 1.6 cm. Eighty-two patients (85%) had a full-thickness resection. Eight patients (8%) had postoperative complications. Kikuchi classification of submucosal (SM) involvement was reported in 29 (30%) patients. Twelve patients had SM1, two SM2, and fifteen SM3. Following pathology, 24 patients (24.7%) returned for additional surgery or treatment. The overall recurrence rate was 14.4% (14 patients), with 11 patients having a local recurrence and 6 having a systemic metastatic recurrence, 3 of which had both. The mean time for recurrence was 2.78 ± 2.8 years and the overall mortality rate was 11%. On univariable and multivariable logistic regression analysis of recurrence vs. non-recurrence groups, the strongest and most significant association and possible risk factors for recurrence were larger lesions (4.3 vs. 2.5 cm, p < 0.001) with an OR of 6.67 (CI-1.82-24.36), especially for tumors larger than 3.5 cm, mucinous histology (14.3% vs. 1.2%, p = 0.004, OR of 14.02, CI-1.13-173.85), and involved margins (41.7% vs. 16.2%, p = 0.003, OR of 9.59, CI-2.14-43.07). The open transanal excision (TAE) approach was also identified as a possible significant risk factor in univariant analysis, while SM3 level penetration showed only a trend. Conclusion: Surgical local excision of T1 rectal malignancy is a safe and viable option. Still, one in four patients received additional treatment. There is an almost 15% chance for recurrence, especially in large tumors, mucinous histology, or involved margin cases. These high-risk patients might warrant additional intervention and stricter surveillance protocols.

Early rectal cancer: The diagnostic performance of MRI supplemented with a rectal micro-enema and a modified staging system to identify tumors eligible for local excision

Background

In staging early rectal cancers (ERC), submucosal tumor depth is one of the most important features determining the possibility of local excision (LE). The micro-enema (Bisacodyl) induces submucosal edema and may hypothetically improve the visualization of tumor depth.

Purpose

To test the diagnostic performance of MRI to identify ERC suitable for LE when adding a pre-procedural micro-enema and concurrent use of a modified classification system.

Material and Methods

In this prospective study, we consecutively included 73 patients with newly diagnosed rectal tumors. Two experienced radiologists independently interpreted the MRI examinations, and diagnostic performance was calculated for local tumors eligible for LE (Tis-T1sm2, n = 43) and non-local tumors too advanced for LE (T1sm3-T3b, n = 30). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were registered for each reader. Inter- and intra-reader agreements were assessed by kappa statistics. Lymph node status was derived from the clinical MRI reports.

Results

Reader1/reader2 achieved sensitivities of 93%/86%, specificities of 90%/83%, PPV of 93%/88%, and NPV of 90%/81%, respectively, for identifying tumors eligible for LE. Rates of overstaging of local tumors were 7% and 14% for the two readers, and kappa values for the inter- and intra-reader agreement were 0.69 and 0.80, respectively. For tumors ≤T2, all metastatic lymph nodes were smaller than 3 mm on histopathology.

Conclusion

MRI after a rectal micro-enema and concurrent use of a modified staging system achieved good diagnostic performance to identify tumors suitable for LE. The rate of overstaging of local tumors was comparable to results reported in previous endorectal ultrasound (ERUS) studies.

The Value of Transanal Normal Saline Infusion-Assisted Multipath Ultrasonography in the Diagnosis of T1/T2 Rectal Cancer

ABSTRACT

This study aims to assess the application value of transanal normal saline infusion-assisted multipath ultrasonography (TNSI-MU) in the diagnosis of T1/T2 rectal cancer (RC). All patients first received single-path 360-degree transrectal ultrasonography and then received 360-degree transrectal ultrasonography, transabdominal ultrasonography, or transvaginal ultrasonography after TNSI to determine the T stage. With surgical pathology as the criterion standard, the detection rates of T1/T2 RC lesions and the T-staging results of single-path 360-degree transrectal ultrasonography, TNSI-MU, and contrast-enhanced magnetic resonance imaging (MRI) were compared and analyzed. T1/T2 RC was surgically and pathologically confirmed in 52 patients. Single-path 360-degree transrectal ultrasonography had a lesion detection rate of 57.69% (30/52) and a T-staging accuracy of 80.0% (24/30), the sensitivity was 57.69%, and the specificity was 88.46%. Transanal normal saline infusion-assisted multipath ultrasonography had a lesion detection rate of 100%, and its T-staging accuracy was 84.62% (44/52), the sensitivity was 100%, and the specificity was 88.61%. Transanal normal saline infusion-assisted multipath ultrasonography had a significantly higher detection rate of T1/T2 RC lesions than single-path 360-degree transrectal ultrasonography ( P < 0.001), but the 2 methods had similar T-staging accuracy for T1/T2 RC (χ 2 = 0.286, P = 0.593). Contrast-enhanced MRI had a lesion detection rate of 100% and a T-staging accuracy of 40.38% (21/52), the sensitivity was 98.07%, and the specificity was 61.54%. Transanal normal saline infusion-assisted multipath ultrasonography had significantly higher diagnostic accuracy than contrast-enhanced MRI for T staging of T1/T2 RC ( P < 0.001), and the diagnostic results of the 2 methods were not consistent (κ = 0.151). Transanal normal saline infusion-assisted multipath ultrasonography outperformed single-path 360-degree transrectal ultrasonography in the detection rate of T1/T2 RC lesions and contrast-enhanced MRI in the staging accuracy for T1/T2 RC.

Transanal minimally invasive surgery (TAMIS) for local excision of benign and malignant rectal neoplasia: a 7-year experience

PURPOSE

Transanal minimally invasive surgery (TAMIS) is an advanced transanal platform that can be utilised to perform high-quality local excision (LE) of rectal neoplasia. This study describes clinical and midterm oncological outcomes from a single unit's 7-year experience with TAMIS.

METHODS

Consecutive patients who underwent TAMIS LE at our institution between January 1st, 2016, and December 31st, 2022, were identified from a prospectively maintained database. Indication for TAMIS LE was benign lesions not amenable to endoscopic excision or histologically favourable early rectal cancers. The primary endpoints were resection quality, disease recurrence and peri-operative outcomes. The Kaplan-Meier survival analyses were used to describe disease-free survival (DFS) for patients with rectal adenocarcinoma that did not receive immediate salvage proctectomy.

RESULTS

There were 168 elective TAMIS LE procedures performed for 102 benign and 66 malignant lesions. Overall, a 95.2% negative margin rate was observed, and 96.4% of lesions were submitted without fragmentation. Post-operative morbidity was recorded in 8.3% of patients, with post-operative haemorrhage, being the most common complication encountered. The mean follow-up was 17 months (SD 15). Local recurrence occurred in 1.6%, and distant organ metastasis was noted in 1.6% of patients.

CONCLUSIONS

For carefully selected patients, TAMIS for local excision of early rectal neoplasia is a valid option with low morbidity that maintains the advantages of organ preservation.

Magnifying chromoendoscopy is a reliable method in the selection of rectal neoplasms for local excision

PURPOSE

Adequate staging of early rectal neoplasms is essential for organ-preserving treatments, but magnetic resonance imaging (MRI) frequently overestimates the stage of those lesions. We aimed to compare the ability of magnifying chromoendoscopy and MRI to select patients with early rectal neoplasms for local excision.

METHODS

This retrospective study in a tertiary Western cancer center included consecutive patients evaluated by magnifying chromoendoscopy and MRI who underwent en bloc resection of nonpedunculated sessile polyps larger than 20 mm, laterally spreading tumors (LSTs) [Formula: see text] 20 mm, or depressed-type lesions of any size (Paris 0-IIc). Sensitivity, specificity, accuracy, and positive and negative predictive values of magnifying chromoendoscopy and MRI to determine which lesions were amenable to local excision (i.e., [Formula: see text] T1sm1) were calculated.

RESULTS

Specificity of magnifying chromoendoscopy was 97.3% (95% CI 92.2-99.4), and accuracy was 92.7% (95% CI 86.7-96.6) for predicting invasion deeper than T1sm1 (not amenable to local excision). MRI had lower specificity (60.5%, 95% CI 43.4-76.0) and lower accuracy (58.3%, 95% CI 43.2-72.4). Magnifying chromoendoscopy incorrectly predicted invasion depth in 10.7% of the cases in which the MRI was correct, while magnifying chromoendoscopy provided a correct diagnosis in 90% of the cases in which the MRI was incorrect (p = 0.001). Overstaging occurred in 33.3% of the cases in which magnifying chromoendoscopy was incorrect and 75% of the cases in which MRI was incorrect.

CONCLUSION

Magnifying chromoendoscopy is reliable for predicting invasion depth in early rectal neoplasms and selecting patients for local excision.

Completion Total Mesorectal Excision: A Case-Matched Comparison With Primary Resection

Objectives

The aim of this study was to compare the perioperative and oncological results of completion total mesorectal excision (cTME) versus primary total mesorectal excision (pTME).

Background

Early-stage rectal cancer can be treated by local excision alone, which is associated with less surgical morbidity and improved functional outcomes compared with radical surgery. When high-risk histological features are present, cTME is indicated, with possible worse clinical and oncological outcomes compared to pTME.

Methods

This retrospective cohort study included all patients that underwent TME surgery for rectal cancer performed in 11 centers in the Netherlands between 2015 and 2017. After case-matching, we compared cTME with pTME. The primary outcome was major postoperative morbidity. Secondary outcomes included the rate of restorative procedures and 3-year oncological outcomes.

Results

In total 1069 patients were included, of which 35 underwent cTME. After matching (1:2 ratio), 29 cTME and 58 pTME were analyzed. No differences were found for major morbidity (27.6% vs 19.0%; P = 0.28) and abdominoperineal excision rate (31.0% vs 32.8%; P = 0.85) between cTME and pTME, respectively. Local recurrence (3.4% vs 8.6%; P = 0.43), systemic recurrence (3.4% vs 12.1%; P = 0.25), overall survival (93.1% vs 94.8%; P = 0.71), and disease-free survival (89.7% vs 81.0%; P = 0.43) were comparable between cTME and pTME.

Conclusions

cTME is not associated with higher major morbidity, whereas the abdominoperineal excision rate and 3-year oncological outcomes are similar compared to pTME. Local excision as a diagnostic tool followed by completion surgery for early rectal cancer does not compromise outcomes and should still be considered as the treatment of early-stage rectal cancer.

Management of Significant Polyp and Early Colorectal Cancer Is Optimized by Implementation of a Dedicated Multidisciplinary Team Meeting: Lessons Learned From the United Kingdom National Program

BACKGROUND

The concept of significant polyps and early colorectal cancer encompasses complex polyps not amenable to routine snare polypectomy or where malignancy cannot be excluded. The assessment and management of these lesions is contentious and increasingly important due to the significant risk of over- or undertreatment.

OBJECTIVE

Following the recommendations of the Significant Polyps and Early Colorectal Cancer National Program, we implemented a dedicated multidisciplinary team meeting and analyzed the influence on patient outcomes.

DESIGN

This was a retrospective study using a prospectively collected database of patients discussed at the dedicated multidisciplinary team meeting.

SETTINGS

This study was conducted in a single tertiary-care center.

PATIENTS

Consecutive patients with significant polyps and early colorectal cancer were identified either through the Bowel Cancer Screening Program or colonoscopy for symptomatic patients.

MAIN OUTCOME MEASURES

Proportions of patients who had organ preservation, and secondary treatment and recurrence rate served as outcome measures.

RESULTS

Overall, 135 patients discussed at the dedicated multidisciplinary team meeting were included, with a median age of 71 years. Median size of the lesions was 25 mm, and 39% were in the rectum. Patients were discussed either after the lesion was removed during the initial colonoscopy (n = 38), of whom 16 (42%) had unexpected cancer, or had no initial treatment with subsequent case review (n = 97). Of these 97 patients, 46 underwent endoscopic excision (26% cancer), 20 trans-anal excision (10% cancer), 23 primary surgical resection (35% cancer), and 8 had no treatment. In 104 (82%) patients, organ preservation was achieved. Secondary surgery was required in 7 of 104 (6.7%) patients after local excision due to radical treatment of high-risk T1 lesions, local recurrence, or patients' decisions. The cumulative hazard estimates for recurrence after a median follow-up of 18.5 months was less than 10% for both benign and malignant lesions.

LIMITATIONS

This study was limited by its relatively small sample size and single-center setting.

CONCLUSIONS

A dedicated multidisciplinary team meeting improved the management of significant polyps and early colorectal cancer, safely refining organ preservation for patients, with low recurrence rates. See Video Abstract at http://links.lww.com/DCR/B826.

MANEJO DE SPECC PLIPO COMPLEJO Y CNCER COLORRECTAL TEMPRANO ES OPTIMIZADO MEDIANTE LA IMPLEMENTACIN DE REUNIONES DE UN EQUIPO MULTIDISCIPLINARIO ESPECIALIZADOS LECCIONES APRENDIDAS DEL PROGRAMA NACIONAL DEL REINO UNIDO

ANTECEDENTES:El concepto de pólipos complejos y cáncer colorrectal temprano abarca engloba pólipos avanzados que no es posible la reseccion endoscopica rutinaria, o aquellos en los que no se puede excluir malignidad. La evaluación y el manejo de estas lesiones es controversial y cada vez más importante debido al riesgo significativo de ser tratadas o no.OBJETIVO:Siguiendo las recomendaciones del Programa Nacional de Pólipos Complejos y Cáncer Colorrectal Temprano, implementamos reuniónes del equipo multidisciplinario especializado y analizamos el impacto en los resultados de los pacientes.DISEÑO:Estudio retrospectivo sobre una base de datos recopilada prospectivamente de los pacientes discutidos en la reunión del equipo multidisciplinario especializado.AJUSTE:Este estudio se realizó en un centro de atención terciaria.PACIENTES:Pacientes consecutivos con pólipos complejos y cáncer colorrectal temprano identificado a través del Programa de detección de cáncer intestinal o colonoscopia para pacientes sintomáticos.PRINCIPALES MEDIDAS DE RESULTADO:Proporción de pacientes que tuvieron preservación de órganos, tratamiento secundario y tasa de recurrencia.RESULTADOS:En total, se incluyeron 135 pacientes discutidos en la reunión del equipo multidisciplinario especializado dedicada, con una media de edad de 71 años. El tamaño medio de las lesiones fue de 25 mm y el 39% estaban en el recto. Se discutio de los pacientes después de que se resecara la lesión durante la colonoscopia inicial [n = 38, de los cuales 16 (42%) tenían un cáncer imprevisto] o no recibieron tratamiento de inicio, con revisión posterior del caso (n = 97). De estos, 46/97 fueron sometidos a resección endoscópica (26% cáncer), 20/97 resección transanal (10% cáncer), 23/97 resección quirúrgica primaria (35% cáncer) y 8/97 no recibieron tratamiento. En 104 (82%) pacientes, se logró la preservación de órgano. Cirugía secundaria fue requeria en 7/104 (6,7%) pacientes después de la resección local debido a tratamiento radical de lesiones T1 de alto riesgo, recidiva local o decisión del paciente. Las estimaciones de riesgo acumulativo de recurrencia después de una media de seguimiento de 18,5 meses fue inferior al 10% tanto para las lesiones benignas como para las malignas.LIMITACIONES:Tamaño de muestra relativamente pequeño y entorno de un solo centro.CONCLUSIONES:La Reunion del equipo multidisciplinario especializado mejoró el manejo de los pólipos complejos y cáncer colorrectal temprano, refinando de manera segura la preservación de órganos para los pacientes, con bajas tasas de recurrencia. Consulte Video Resumen en http://links.lww.com/DCR/B826. (Traducción- Dr. Francisco M. Abarca-Rendon).

Can Ultrasound Elastography Discriminate between Rectal Adenoma and Cancer? A Systematic Review

BACKGROUND

Rectal cancer is a common malignancy. Since the introduction of bowel-screening programs, the number of patients with advanced adenomas and early rectal cancer has increased. Despite improved diagnostics, the discrimination between rectal adenomas and early rectal cancer (i.e., pT1-T2) remains challenging. The purpose of this systematic review was to evaluate the diagnostic performance of endorectal ultrasound (ERUS) elastography in discriminating rectal adenomas from cancer.

METHOD

Using PRISMA guidelines, a systematic search was performed on PubMed, Embase, and MEDLINE databases. Studies evaluating the primary staging of rectal adenomas and cancer using ERUS elastography were included.

RESULTS

Six studies were identified; three evaluated the discrimination between adenomas and cancer; two evaluated adenomas and early rectal cancer (i.e., pT1-T2); one evaluated performance on different T categories. All studies reported increased diagnostic accuracy of ERUS elastography compared to ERUS. Sensitivity, specificity and accuracy ranged 0.93-1.00, 0.83-1.00 and 0.91-1.00, respectively, when discriminating adenomas from cancer. In the differentiation between adenomas and early rectal cancer, the sensitivity, specificity and accuracy were 0.82-1.00, 0.86-1.00 and 0.84-1.00, respectively.

CONCLUSION

Elastography increases the accuracy of ERUS and may provide valuable information on malignant transformation of rectal lesions.

Completion total mesorectal excision following transanal endoscopic microsurgery does not compromise outcomes in patients with rectal cancer

BACKGROUND

Transanal endoscopic microsurgery (TEM) represents a choice of treatment in patients with neoplastic lesions in the rectum. When TEM fails, completion total mesorectal excision (cTME) is often required. However, a concern is whether cTME increases the rate of abdominoperineal resections (APR) and is associated with higher risk of incomplete mesorectal fascia (MRF) resection. The aim of this study was to compare outcomes of cTME with primary TME (pTME) in patients with rectal cancer.

METHODS

This was a nationwide study on all patients with cTME from the Danish Colorectal Cancer Group database between 2005 and 2015. Patients with cTME were compared to patients with pTME after propensity score matching (matching ratio 1:2). Matching variables were age, gender, tumor distance from anal verge, American Society of Anesthesiologists (ASA) score and American Joint Committee on Cancer (AJCC) stage.

RESULTS

A total of 60 patients with cTME were compared with 120 patients with pTME. Patients with cTME experienced more intraoperative complications as compared to pTME patients (18.3% vs. 6.7%, p = 0.021). However, there was no difference in the rate of perforations at or near the tumor/previous TEM site (6.7% vs. 2.5%, p = 0.224), conversion to open surgery (p = 0.733) or 30-day morbidity (p = 0.86). On multivariate analysis, cTME was not a risk factor for APR (OR 2.49; 95% CI 0.95-6.56; p = 0.064) or incomplete MRF (OR 1.32; 95% CI 0.48-3.63; p = 0.596). There was no difference in the rate of local recurrence between cTME and pTME (5.2% vs. 4.3%, p = 0.1), distant metastases (6.8% vs. 6.8%, p = 1), or survival (p = 0.081). The mean follow-up time was 6 years.

CONCLUSION

In our study, the largest so far on the subject, we find no difference in postoperative short- or long-term outcomes between cTME and pTME.

Local recurrence after local excision of early rectal cancer: a meta-analysis of completion TME, adjuvant (chemo)radiation, or no additional treatment

BACKGROUND

The risks of local recurrence and treatment-related morbidity need to be balanced after local excision of early rectal cancer. The aim of this meta-analysis was to determine oncological outcomes after local excision of pT1-2 rectal cancer followed by no additional treatment (NAT), completion total mesorectal excision (cTME) or adjuvant (chemo)radiotherapy (aCRT).

METHODS

A systematic search was conducted in PubMed, Embase and the Cochrane Library. The primary outcome was local recurrence. Statistical analysis included calculation of the weighted average of proportions.

RESULTS

Some 73 studies comprising 4674 patients were included in the analysis. Sixty-two evaluated NAT, 13 cTME and 28 aCRT. The local recurrence rate for NAT among low-risk pT1 tumours was 6·7 (95 per cent c.i. 4·8 to 9·3) per cent. There were no local recurrences of low-risk pT1 tumours after cTME or aCRT. The local recurrence rate for high-risk pT1 tumours was 13·6 (8·0 to 22·0) per cent for local excision only, 4·1 (1·7 to 9·4) per cent for cTME and 3·9 (2·0 to 7·5) per cent for aCRT. Local recurrence rates for pT2 tumours were 28·9 (22·3 to 36·4) per cent with NAT, 4 (1 to 13) per cent after cTME and 14·7 (11·2 to 19·0) per cent after aCRT.

CONCLUSION

There is a substantial risk of local recurrence in patients who receive no additional treatment after local excision, especially those with high-risk pT1 and pT2 rectal cancer. The lowest recurrence risk is provided by cTME; aCRT has outcomes comparable to those of cTME for high-risk pT1 tumours, but shows a higher risk for pT2 tumours.