Risk factors of circumferential resection margin involvement in the patients with extraperitoneal rectal cancer

Downstaging in Advanced Rectal Cancers: A Propensity-Matched Comparison Between Short-Course Radiotherapy Followed by Chemotherapy and Long-Course Chemoradiotherapy

BACKGROUND

Short-course radiotherapy followed by chemotherapy has not been widely evaluated as an alternative to traditional long-course chemoradiotherapy in locally advanced rectal cancer.

OBJECTIVE

This study compared the oncological and short-term outcomes between short-course radiotherapy + chemotherapy and long-course chemoradiotherapy in locally advanced rectal cancer.

DESIGN

This is a retrospective propensity-matched study.

SETTINGS

The study was conducted in a colorectal department at a tertiary care oncology center in India.

PATIENTS

There were 173 patients. Group A had 47 patients and group B had 126 patients. A 1:2.7 matching was done for age, sex, distance of tumor from the anal verge, sphincter preservation surgeries, MRI-based pretreatment T stage, and circumferential resection margin.

INTERVENTIONS

The interventions performed were short-course radiotherapy + chemotherapy (group A) and long-course chemoradiotherapy (group B) in locally advanced rectal cancer.

MAIN OUTCOME MEASURES

The primary measures were pathological circumferential resection margin positivity, downstaging, tumor regression grade, and postoperative complications.

RESULTS

Of the patients, 52% had a positive circumferential resection margin on MRI, 57% had low rectal tumors, and 20% had T4 tumors. Distribution of rectal surgeries was similar between the 2 groups. pT downstaging and tumor regression scores were significantly better in group B ( p = 0.028 and 0.026). Pathological circumferential resection margin, distal resection margin, and nodal yield were similar. On multivariate analysis, pretreatment N status was the only independent predictive factor for pathological circumferential resection margin status. Grade 3 to 4 Clavien-Dindo complications, anastomotic leak rates, and hospital stay were similar between the 2 groups.

LIMITATIONS

This was a retrospective study. Although propensity matching was performed, selection bias cannot be eliminated completely, as seen in the difference in the surgical approaches between the 2 groups.

CONCLUSIONS

In a cohort containing a significant portion of MRI circumferential resection margin-positive low rectal cancers, short-course radiotherapy + chemotherapy followed by delayed surgery resulted in lower T downstaging and lower tumor regression scores compared with long-course chemoradiotherapy, but pathological circumferential margin status, distal resection margin, nodal yield, and perioperative morbidity were similar between the 2 groups. This suggests that short-course radiotherapy + chemotherapy could be a viable alternative to long-course chemoradiotherapy in locally advanced rectal cancers. See Video Abstract at http://links.lww.com/DCR/B855 .

REDUCCIN DEL ESTADIO EN LOS CNCERES RECTALES AVANZADOS UNA COMPARACIN DE PROPENSIN EQUIPARADA ENTRE LA RADIACIN DE CICLO CORTO SEGUIDA DE QUIMIOTERAPIA Y LA QUIMIO RADIACIN DE CICLO LARGO

ANTECEDENTES:La radioterapia de ciclo corto seguida de quimioterapia no ha sido evaluada ampliamente como una alternativa a la tradicional quimio radioterapia de ciclo largo en el cáncer de recto localmente avanzado.OBJETIVO:Estudio que compara los resultados oncológicos y a corto plazo entre la radioterapia de ciclo corto + quimioterapia y la quimio radioterapia de ciclo largo en el cáncer de recto localmente avanzado.DISEÑO:Estudio comparado de propensión de manera retrospectiva.AJUSTE:Departamento colorrectal en un centro de atención oncológica de tipo terciario en la India.PACIENTES:Hubo 173 pacientes. El grupo A tenía 47 y el grupo B tenía 126 pacientes. Se realizó una comparación de 1: 2,7 para edad, sexo, distancia del tumor desde el margen anal, cirugías de preservación del esfínter, estadio T previo al tratamiento basada en resonancia magnética y margen de resección circunferencial (CRM).INTERVENCIONES:Radioterapia de ciclo corto + quimioterapia (grupo A) y quimio radioterapia de ciclo largo (grupo B) en cáncer de recto localmente avanzado (LARC).PRINCIPALES MEDIDAS DE RESULTADO:Positividad histopatológica de CRM, reducción del estadio tumoral, grado de regresión tumoral, complicaciones posoperatorias.RESULTADOS:El 52% de los pacientes han tenido un margen de resección circunferencial positivo en la resonancia magnética, 57% de tumores rectales bajos, 20% de tumores T4. La distribución de cirugías rectales fue similar entre los 2 grupos. Las puntuaciones de regresión tumoral y de reducción del estadio de pT fueron significativamente mejores en el grupo B ( p = 0.028 y 0.026 respectivamente). El margen de resección circunferencial patológico, el margen de resección distal y los ganglios arrojados fueron similares. En el análisis multivariado, el estadio N previo al tratamiento fue el único factor predictivo independiente para el estadio de pCRM. Las complicaciones Clavien-Dindo de grado 3-4, las tasas de fuga anastomótica y la estancia hospitalaria fueron similares entre los dos grupos.LIMITACIONES:Retrospectiva; aunque la propensión coincide, existe potencial sesgo de selección.CONCLUSIONES:En una cohorte que contenía una porción significativa de cánceres rectales bajos con margen de resección circunferencial positivo por resonancia magnética, la radioterapia de ciclo corto + quimioterapia seguida de cirugía tardía dio como resultado una mayor reducción del estadio T y de regresión tumoral en comparación con la quimio radioterapia de ciclo largo. Pero el estatus histopatológico del margen circunferencial, el margen de resección distal, el rendimiento ganglionar y la morbilidad perioperatoria fueron similares entre los dos grupos. Esto sugiere que la radioterapia de ciclo corto + quimioterapia podría ser una alternativa viable a la quimio radioterapia de ciclo largo en cánceres rectales localmente avanzados. Consulte Video Resumen en http://links.lww.com/DCR/B855 . (Traducción-Dr. Osvaldo Gauto ).

An MRI-based pelvimetry nomogram for predicting surgical difficulty of transabdominal resection in patients with middle and low rectal cancer

Objective

The current work aimed to develop a nomogram comprised of MRI-based pelvimetry and clinical factors for predicting the difficulty of rectal surgery for middle and low rectal cancer (RC).

Methods

Consecutive mid to low RC cases who underwent transabdominal resection between June 2020 and August 2021 were retrospectively enrolled. Univariable and multivariable logistic regression analyses were carried out for identifying factors (clinical factors and MRI-based pelvimetry parameters) independently associated with the difficulty level of rectal surgery. A nomogram model was established with the selected parameters for predicting the probability of high surgical difficulty. The predictive ability of the nomogram model was assessed by the receiver operating characteristic (ROC) curve and decision curve analysis (DCA).

Results

A total of 122 cases were included. BMI (OR = 1.269, p = 0.006), pelvic inlet (OR = 1.057, p = 0.024) and intertuberous distance (OR = 0.938, p = 0.001) independently predicted surgical difficulty level in multivariate logistic regression analysis. The nomogram model combining these predictors had an area under the ROC curve (AUC) of 0.801 (95% CI: 0.719–0.868) for the prediction of a high level of surgical difficulty. The DCA suggested that using the nomogram to predict surgical difficulty provided a clinical benefit.

Conclusions

The nomogram model is feasible for predicting the difficulty level of rectal surgery, utilizing MRI-based pelvimetry parameters and clinical factors in mid to low RC cases.

Transanal Total Mesorectal Excision for Malignant Rectal Lesion: A Prospective Cohort Study

AIMS: The main outcome of this study was to use the transanal total mesorectal excision (TaTME) technique for rectal cancer resection and to assess as a primary endpoint the short-term oncological outcome; in terms of circumferential resection margin, longitudinal resection margins (proximally and distally), and lymph nodes (LN) retrieval, while secondary endpoints were operative time, estimated blood loss, length of hospital stay, cost per case, and overall complication rate. METHODS: This was a prospective cohort study. Forty patients were included and subjected to TaTME from May 2018 to January 2020 and patients were followed up for a period of 6 months. RESULTS: Primary endpoint: Depending on the post-operative specimen pathological assessment; circumferential resection margin (CRM) was free in all patients, proximal resection margins had a mean 14.37 2.87 cm, distal resection margins had a mean 2.08 ± 0.4 cm and LNs retrieval had a mean 13.27 ± 5.9, and number of positive LNs had a mean 2.40 ± 3.77. Secondary endpoints: Mean total operative time (from induction of anesthesia till skin closure) was 179.10, estimated blood loss (using gauze visual analog plus what was obtained in the OR suction device) was 133.67 66.59 ml, the length of hospital stay (admission till discharge) was 5.27 ± 1.08 days, cost per case had a mean (in 1000 USD) 2.95 ± 0.12, and overall complication rate was 10%. CONCLUSION: TaTME represents a promising complementary technique to laparoscopic TME in the step of low rectal dissection.

Pelvic dimensions on preoperative imaging can identify poor-quality resections after laparoscopic low anterior resection for mid- and low rectal cancer

BACKGROUND

High-quality surgery is essential for optimal oncologic outcomes in rectal cancer, but total mesorectal excision (TME) can be difficult for mid- and low rectal cancers. Preoperative identification of patients at risk for difficult TME may change the operative approach. The objective of this study was to determine if MRI pelvimetry can predict poor-quality surgery in patients undergoing laparoscopic low anterior resection (LAR) for mid- and low rectal cancer.

METHODS

All patients undergoing laparoscopic LAR for rectal cancer ≤ 9 cm from the anal verge at a single tertiary care referral center from 2011 to 2017 were retrospectively reviewed. Pelvic dimensions were measured from preoperative staging MRI on sagittal and axial views. Pelvimetry variables were all dichotomized based on median values. Exploratory factor analysis then identified the most relevant variables for regression analysis. The primary outcome was poor-quality resection, defined as an incomplete mesorectal grade, or involved circumferential (CRM) or distal (DRM) resection margins.

RESULTS

There were 92 patients included in this study, of which 70% were male, the mean BMI was 26.0 kg/m², and the mean tumor height was 6.6 cm. Preoperative (chemo)radiotherapy was administered in 70%, and the pathologic T-stage was T3/T4 in 41%. The overall incidence of poor-quality resection was 17%, including 13% incomplete TME, 7% involved CRM, and 1% involved DRM. Factor analysis identified S1-pubic symphysis and the angle between S1 and S5-bottom of symphysis (angle ABD) as relevant variables. After adjusting for pathologic T-stage, BMI, and tumor height, a S1-S5-bottom of symphysis angle > 74.3^° (OR 6.19, 95% CI 1.18-32.37) independently predicted poor-quality resection.

CONCLUSIONS

MRI pelvimetry can identify patients at risk for a poor-quality resection after laparoscopic proctectomy for mid- and low rectal cancer. These patients may benefit from the selective use of more advanced access methods to improve surgical resection quality.

Summary of Oncologic and Functional Outcomes

Large cohort and collaborative studies to date have shown that the short-term oncological outcomes appear to be at least as good as traditional laparoscopic surgery. These results need confirmation in randomized controlled trials, which are currently underway (GRECCAR 11 and COLOR III). The functional data on transanal total mesorectal excision is still very scarce and more mature data on quality of life and function outcomes are eagerly awaited.

Implementing new surgical technology: a national perspective on case volume requirement for proficiency in transanal total mesorectal excision

Background

Early data suggest that transanal total mesorectal excision (TaTME) is a safe alternative to the abdominal approach for rectal cancer. This study aims to understand the approach to the management of rectal cancer in Canada and to ascertain perspectives on introducing TaTME.

Methods

Surgeons were invited to complete a survey that asked about their management practices relating to rectal cancer and their opinions regarding TaTME.

Results

Ninety-four surgeons completed the survey (38% response rate). The number of rectal cancer cases handled annually by surgeons varied widely (1–80 cases, median 15 cases). Twenty-seven percent of respondents performed TaTME at the time of the survey, and 43% of those who did not said they planned on learning the technique. Surgeons who performed TaTME felt that a higher annual volume of rectal cancer cases was required to maintain proficiency than did non-TaTME surgeons (median 20 cases [interquartile range (IQR) 15–25 cases] v. 15 cases [IQR 10–20 cases]). Surgeons who performed TaTME also felt that a higher annual volume of TaTME cases was required to maintain proficiency (median 12 cases [IQR 10–19 cases] v. 9 cases [IQR 5–10 cases]).

Conclusion

These findings help define the current practice environment for rectal cancer surgeons in Canada and highlight the complex issues associated with learning TaTME.

[Transanal mesorectumectomy for rectal cancer - is it optimal surgery for 'difficult' patients?]

AIM

To compare short-term outcomes after transanal total mesorectumectomy (Ta-TME) and laparoscopic (Lap-TME) procedure in 'difficult' patients.

MATERIAL AND METHODS

Prospective nonrandomized trial included patients with confirmed middle-/low rectum adenocarcinoma T1-4aN0-2M0 for the period November 2013 - September 2016. We identified 20 out of 55 in TA-TME and 14 out of 54 patients in Lap-TME group as those of 'difficult' subgroup: male, BMI ≥25 кг/м², previous chemoradiotherapy (CRT).

RESULTS

Time of surgery, blood loss, conversions rate, postoperative morbidity and length of hospital-stay were similar in both groups. Hardware anastomoses were more frequent in TA-TME compared with LAP-TME group (78.9% vs. 50%, p=0.086). Specimen quality was more favorable in TA-TME group: Grade I 10% in Ta-TME group vs. 28.6% in Lap-TME group; 'positive' CRM 5% vs. 14.3%, р=0.365. Within-group analysis did not reveal any differences between 'difficult' and 'typical' patients by surgical and pathomorphological characteristics in TA-TME group in contrast to Lap-TME group. Median of follow-up was 24.6 (IR 10.6-40.2) and 23.8 (IR 12.1-39.9) months for TA-TME and Lap-TME groups, respectively. Local recurrence occurred in 1 (1.8%) 'difficult' patient after Ta-TME. Distant metastases were observed in 1 (1.8%) patient of Ta-TME and 2 (3.7%) patients of Lap-TME group. Actuarial 3-years reccurence-free survival was 95.7% for Ta-TME and 93.9% for Lap-TME group, respectively (p=0.923).

CONCLUSION

TA-TME is advisable for 'difficult' patients. Further multicenter randomized trials are necessary to specify the effectiveness of TA-TME in these patients.

Transanal Total Mesorectal Excision: Why, When, and How

Transanal total mesorectal excision (taTME) has evolved over the past decade fueled by advances in minimally invasive surgery. The technique aims to overcome the constraints posed by a narrow rigid pelvis and poor TME visualization that are encountered during "top-down" rectal surgery. A more accurate pelvic dissection should subsequently result in safer oncological resections and better preservation of pelvic autonomic nerves. taTME is an advanced complex technique that requires dedicated training and experience in TME surgery. Initial results from small cohorts are promising and confirmation by randomized controlled trials is eagerly awaited.

Transanal Total Mesorectal Excision: International Registry Results of the First 720 Cases

OBJECTIVE

This study aims to report short-term clinical and oncological outcomes from the international transanal Total Mesorectal Excision (taTME) registry for benign and malignant rectal pathology.

BACKGROUND

TaTME is the latest minimally invasive transanal technique pioneered to facilitate difficult pelvic dissections. Outcomes have been published from small cohorts, but larger series can further assess the safety and efficacy of taTME in the wider surgical population.

METHODS

Data were analyzed from 66 registered units in 23 countries. The primary endpoint was "good-quality TME surgery." Secondary endpoints were short-term adverse events. Univariate and multivariate regression analyses were used to identify independent predictors of poor specimen outcome.

RESULTS

A total of 720 consecutively registered cases were analyzed comprising 634 patients with rectal cancer and 86 with benign pathology. Approximately, 67% were males with mean BMI 26.5 kg/m. Abdominal or perineal conversion was 6.3% and 2.8%, respectively. Intact TME specimens were achieved in 85%, with minor defects in 11% and major defects in 4%. R1 resection rate was 2.7%. Postoperative mortality and morbidity were 0.5% and 32.6% respectively. Risk factors for poor specimen outcome (suboptimal TME specimen, perforation, and/or R1 resection) on multivariate analysis were positive CRM on staging MRI, low rectal tumor <2 cm from anorectal junction, and laparoscopic transabdominal posterior dissection to <4 cm from anal verge.

CONCLUSIONS

TaTME appears to be an oncologically safe and effective technique for distal mesorectal dissection with acceptable short-term patient outcomes and good specimen quality. Ongoing structured training and the upcoming randomized controlled trials are needed to assess the technique further.

Transanal total mesorectal excision for rectal cancer: early outcomes in 50 consecutive patients

AIM

Minimally invasive approaches to proctectomy for rectal cancer have not been widely adopted due to inherent technical challenges. A modification of traditional transabdominal mobilization, termed transanal total mesorectal excision (TaTME), has the potential to improve access to the distal rectum. The aim of the current study is to assess outcomes following TaTME for rectal cancer.

METHOD

This is a retrospective analysis of a prospectively maintained database of consecutive patients who underwent TaTME for rectal cancer at a single institution. The study period was from 1 March 2012 to 31 July 2015.

RESULTS

During the study period 50 patients underwent TaTME. The median tumour distance from the anal verge was 4.4 (3.0-5.5) cm. The rate of conversion from a planned minimally invasive approach was 2.2%. The median operative time was 267.0 (227.0-331.0) min. The median lymph node yield was 18.0 (12.0-23.8), the macroscopic quality assessment of the resected specimen was incomplete in 2% and the circumferential resection margin positivity rate was 4%. Intra-operative morbidity occurred in 6% and the 30 day morbidity rate was 36%. The median length of stay was 4.5 (4.0-8.0) days. The median follow-up was 15.1 (7.0-23.2) months; two patients have developed a local recurrence and eight patients have developed distant recurrence.

CONCLUSION

These data suggest that TaTME for rectal cancer is feasible with an acceptable pathological outcome and morbidity profile. Further data on functional and long-term survival outcomes are required.

Predictors of circumferential resection margin involvement in surgically resected rectal cancer: A retrospective review of 23,464 patients in the US National Cancer Database

INTRODUCTION

The circumferential resection margin (CRM) is a key prognostic factor after rectal cancer resection. We sought to identify factors associated with CRM involvement (CRM+).

METHODS

A retrospective review was performed of the National Cancer Database, 2004-2011. Patients with rectal cancer who underwent radical resection and had a recorded CRM were included. Multivariable analysis of the association between clinicopathologic characteristics and CRM was performed. Tumor <1 mm from the cut margin defined CRM+.

RESULTS AND DISCUSSION

Of 23,464 eligible patients, 13.3% were CRM+. Factors associated with CRM+ were diagnosis later in the study period, lack of insurance, advanced stage, higher grade, undergoing APR, and receiving radiation. Nearly half of CRM+ patients did not receive neoadjuvant therapy. CRM+ patients who did not receive neoadjuvant therapy were more likely to be female, older, with more comorbidities, smaller tumors, earlier clinical stage, advanced pathologic stage, and CEA-negative disease compared to those who received it.

CONCLUSIONS

Factors associated with CRM+ include features of advanced disease, undergoing APR, and lack of health insurance. Half of CRM+ patients did not receive neoadjuvant treatment. These represent cases where CRM status may be modifiable with appropriate pre-operative selection and multidisciplinary management.

Sparing Sphincters and Laparoscopic Resection Improve Survival by Optimizing the Circumferential Resection Margin in Rectal Cancer Patients

The goal of rectal cancer treatment is to minimize the local recurrence rate and extend the disease-free survival period and survival. For this aim, obtainment of negative circumferential radial margin (CRM) plays an important role. This study evaluated predictive factors for positive CRM status and its effect on patient survival in mid- and distal rectal tumors.Patients who underwent curative resection for rectal cancer were included. The main factors were demographic data, tumor location, surgical technique, neoadjuvant therapy, tumor diameter, tumor depth, lymph node metastasis, mesorectal integrity, CRM, the rate of local recurrence, distant metastasis, and overall and disease-free survival. Statistical analyses were performed by using the Chi-squared test, Fisher exact test, Student t test, Mann-Whitney U test and the Mantel-Cox log-rank sum test.A total of 420 patients were included, 232 (55%) of whom were male. We observed no significant differences in patient characteristics or surgical treatment between the patients who had positive CRM and who had negative CRM, but a higher positive CRM rate was observed in patients undergone abdominoperineal resection (APR) (P < 0.001). Advanced T-stage (P < 0.001), lymph node invasion (P = 0.001) and incomplete mesorectum (P = 0.007) were encountered significantly more often in patients with positive CRM status. Logistic regression analysis revealed that APR (P < 0.001) and open resection (P = 0.046) were independent predictors of positive CRM status. Moreover, positive CRM was associated with decreased 5-year overall and disease-free survival (P = 0.002 and P = 0.004, respectively).This large single-institution series demonstrated that APR and open resection were independent predictive factors for positive CRM status in rectal cancer. Positive CRM independently decreased the 5-year overall and disease-free survival rates.

Extralevatory abdominoperineal excision (ELAPE) does not result in reduced rate of tumor perforation or rate of positive circumferential resection margin: a nationwide database study

OBJECTIVE

To evaluate the oncological results and possible benefits associated with extralevatory abdominoperineal excision (ELAPE) when compared with conventional abdominoperineal excision (APE).

BACKGROUND

ELAPE was introduced in 2007 with the purpose of reducing the rate of positive resection margins after resection of low rectal cancers. Preliminary studies have shown promising results. No large-scale or nationwide data have been presented.

METHODS

Database study based on data from the Danish Colorectal Cancer Group's prospective database. Data on all ELAPEs and APEs performed in Denmark in the period January 1, 2009, through August 2012 were retrieved and evaluated for differences in demography, tumor characteristics, and oncological results. Uni- and multivariate logistic regression analyses were performed to identify risk factors for resection with a positive circumferential resection margin (CRM+).

RESULTS

A total of 554 patients were included, 301(54%) were operated by ELAPE; 253(46%) by APE. Sixty-three percent were men, median (interquartile range) age was 69 (61-76 years) years, and tumors removed had predominantly T-stages T2 and T3 (32% and 45%, respectively). Overall, CRM+ was found in 13% of patients. When divided according to type of procedure, we found no significant differences in demography and tumor T- and N-stages. Resections with a CRM+ were more common after ELAPE (16% vs 7%; P = 0.006). After uni- and multivariate logistic regression analyses, surgery by ELAPE remained a risk factor for a CRM+ [odds ratio, 2.59 (95% confidence interval, 1.31-5.12); P = 0.006).

CONCLUSIONS

In this nationwide study, resection of low rectal cancers by ELAPE did not improve short-term oncological results, when compared with conventional APE.