Evaluation of the frequency and pattern of local recurrence following intersphincteric resection for ultra-low rectal cancer

International standardization and optimization group for intersphincteric resection (ISOG-ISR): modified Delphi consensus on anatomy, definition, indication, surgical technique, specimen description and functional outcome

AIM

Intersphincteric resection (ISR) is an oncologically complex operation for very low-lying rectal cancers. Yet, definition, anatomical description, operative indications and operative approaches to ISR are not standardized. The aim of this study was to standardize the definition of ISR by reaching international consensus from the experts in the field. This standardization will allow meaningful comparison in the literature in the future.

METHOD

A modified Delphi approach with three rounds of questionnaire was adopted. A total of 29 international experts from 11 countries were recruited for this study. Six domains with a total of 37 statements were examined, including anatomical definition; definition of intersphincteric dissection, intersphincteric resection (ISR) and ultra-low anterior resection (uLAR); indication for ISR; surgical technique of ISR; specimen description of ISR; and functional outcome assessment protocol.

RESULTS

Three rounds of questionnaire were performed (response rate 100%, 89.6%, 89.6%). Agreement (≥80%) reached standardization on 36 statements.

CONCLUSION

This study provides an international expert consensus-based definition and standardization of ISR. This is the first study standardizing terminology and definition of deep pelvis/anal canal anatomy from a surgical point of view. Intersphincteric dissection, ISR and uLAR were specifically defined for precise surgical description. Indication for ISR was determined by the rectal tumour's maximal radial infiltration (T stage) below the levator ani. A new surgical definition of T3isp was reached by consensus to define T3 low rectal tumours infiltrating the intersphincteric plane. A practical flowchart for surgical indication for uLAR/ISR/abdominoperineal resection was developed. A standardized ISR surgical technique and functional outcome assessment protocol was defined.

Clinical efficacy of different approaches for laparoscopic intersphincteric resection of low rectal cancer: a comparison study

Background

The operative results of different approaches for the laparoscopic intersphincteric resection (LAISR) of low rectal cancer vary, and the patient characteristics associated with the best outcomes for each procedure have not been reported. We compared the efficacy of different approaches for LAISR of low rectal cancer and discussed the surgical indications for each approach.

Methods

We retrospectively reviewed data from 235 patients with low rectal cancer treated via LAISR from October 2010 to September 2016. Patients underwent either the transabdominal approach for ISR (TAISR, n = 142), the transabdominal perineal approach for ISR (TPAISR, n = 57), or the transanal pull-through approach for ISR (PAISR, n = 36).

Results

The PAISR and TAISR groups exhibited shorter operation times and less intraoperative blood loss than the TPAISR group. The anastomotic distance was shorter in the PAISR and TPAISR groups than in the TAISR group. No differences in the ability to perform radical resection, overall complications, postoperative recovery, Wexner score recorded 12 months after ostomy closure, 3-year disease-free survival, local recurrence-free survival, distant metastasis-free survival, or overall survival (OS) were observed among the three groups.

Conclusions

TAISR, TPAISR, and PAISR have unique advantages and do not differ in terms of operation safety, patient outcomes, or anal function. TPAISR requires a longer time to complete and is associated with more bleeding and a slower recovery of anal function. PAISR should be considered when TAISR cannot ensure a negative distal margin and the tumor and BMI are relatively small; otherwise, TPAISR is required.

Robotic Intersphincteric Resection for Low Rectal Cancer: Technical Controversies and a Systematic Review on the Perioperative, Oncological, and Functional Outcomes

Intersphincteric resection (ISR) is the ultimate anus-sparing technique for low rectal cancer and is considered an oncologically safe alternative to abdominoperineal resection. The application of the robotic approach to ISR (RISR) has been described by few specialized surgical teams with several differences regarding approach and technique. This review aims to discuss the technical aspects of RISR by evaluating point by point each surgical controversy. Moreover, a systematic review was performed to report the perioperative, oncological, and functional outcomes of RISR. Postoperative morbidities after RISR are acceptable. RISR allows adequate surgical margins and adequate oncological outcomes. RISR may result in severe bowel and genitourinary dysfunction affecting the quality of life in a portion of patients.

Risk Factors for Anorectal Dysfunction After Interspincteric Resection in Patients With Low Rectal Cancer

Purpose: The objective of this study was to explore the risk factors for anorectal dysfunction after intersphincteric resection in patients with low rectal cancer. Methods: A total of 251 patients who underwent intersphincteric resection from July 2014 to June 2020 were included in this study, for which the Kirwan's grade, Wexner score, and anorectal manometric index were used to evaluate the anorectal function and other parameters including demographics, surgical features, and clinical and pathological characteristics. These parameters were analysed to explore the potential risk factors for anorectal function after intersphincteric resection. Results: In the 251 included patients, 98 patients underwent partial intersphincteric resection, 87 patients underwent subtotal intersphincteric resection, and 66 patients underwent total intersphincteric resection. There were 53 (21.1%) patients who had postoperative complications, while no significant difference was observed between the three groups. Furthermore, 30 patients (45.5%) in the total intersphincteric resection group were classified as having anorectal dysfunction (Kirwan's grade 3-5), which was significantly higher than that in the partial intersphincteric resection group (27.6%) and subtotal intersphincteric resection group (29.9%). The mean Wexner score of patients that underwent total intersphincteric resection was 7.9, which was higher than that of patients that had partial intersphincteric resection (5.9, p = 0.002) and subtotal intersphincteric resection (6.4, p = 0.027). The initial perceived volume was lower in the total intersphincteric resection group than in the partial and subtotal intersphincteric resection groups at 1, 3, and 6 months after intersphincteric resection. In addition, the resting pressure, maximum squeeze pressure, and maximum tolerated volume in the total intersphincteric resection group were worse than those in the partial and subtotal groups at 3 and 6 months after intersphincteric resection. Univariate and multivariate analyses suggested that an age ≥65, total intersphincteric resection, and preoperative chemoradiotherapy were independent risk factors for anorectal dysfunction (P = 0.023, P = 0.003, and P = 0.008, respectively). Among the 66 patients who underwent total intersphincteric resection, 17 patients received preoperative chemoradiotherapy, of which 12 patients (70.6%) were classified as having anorectal dysfunction. Conclusion: The current study concluded that age ≥65, total intersphincteric resection, and preoperative chemoradiotherapy were risk factors for anorectal dysfunction after intersphincteric resection. The morbidity of anorectal dysfunction after total intersphincteric resection for patients who received preoperative chemoradiotherapy was relatively high, and the indication should be carefully evaluated.

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.

Local recurrence with intersphincteric resection in adverse histology rectal cancers. A retrospective study with competing risk analysis

BACKGROUND

The safety of inter-sphincteric resection (ISR) for low rectal cancer with adverse histologic subtypes has been incompletely studied. The present study aims at determining the risk of local recurrence with this procedure in poorly differentiated and signet ring cell (PDSR) adenocarcinoma.

METHODS

Retrospective analysis from a single tertiary cancer centre of non-metastatic primary rectal cancer <6 cm from the anal verge that underwent ISR. Competing risk analysis and sub-distribution hazard ratios for local recurrence free survivals were calculated to determine factors that influenced local recurrence with the competing risk of death from any cause to overcome the exceeding risk of distant metastasis associated with adverse histologic types.

RESULTS

One hundred forty-two patients underwent ISR and 22.6% has PDSR histology. At a median follow up of 61 months, 15.6% of the PDSR cohort developed local recurrence (five patients) compared to 11.7% in the non-PDSR group. PDSR histology influenced overall and disease free survival but not local recurrence on cox regression. On competing risk analysis, only ypT stage ≥3 predicted worse local recurrence free survival and not histology.

CONCLUSIONS

The presence of PDSR histology did not increase the risk of local recurrence after ISR in this retrospective competing risk analysis.

A quest for sphincter-saving surgery in ultralow rectal tumours-a single-centre cohort study

INTRODUCTION

Despite the progress in the treatment of colorectal cancer, there is still no optimal strategy for tumours located adjacent to the anal sphincter. This study aims to evaluate oncological and functional results of surgery for rectal cancer in unfavourable locations in proximity to anal sphincters.

MATERIALS AND METHODS

Patients with rectal cancer, which was either initially infiltrating the anal sphincter or located in the close proximity of the sphincter, were included in the study. Patients were submitted to extralevator abdominoperineal resection (APR), intersphincteric resection, or transanal total mesorectal excision (TaTME). Primary outcomes were perioperative data: operative time, blood loss, complications, length of stay (LOS), and 30-day mortality. Secondary outcomes were pathological quality of the specimens and functional outcome 6 months after defunctioning ileostomy closure.

RESULTS

Among patients with cancer adjacent to the anal sphincter, 13 (25%) underwent APR, 14 (27%) patients were submitted to intersphincteric resection, and 25 (48%) patients were treated with the TaTME approach. Operative time was 240 (210-270 IQR) for APR, 212.5 (170-260 IQR) for intersphincteric resection, and 270 (240-330 IQR) for TaTME (p = 0.018). Perioperative morbidity was 31% for APR, 36% for intersphincteric resections, and 12% for the TaTME group (p = 0.181). Complete mesorectal excision was achieved in 92% of specimens in the TaTME group, 93% in intersphincteric resections, and 78% in the APR group (p = 0.72). Median circumferential resection margin in APR was 6 mm (4-7 IQR), in intersphincteric resections 7.5 mm (2.5-10 IQR), and in the TaTME group 4 mm (2.8-8 IQR). All patients after intersphincteric resections developed major low anterior resection syndrome (LARS). Four patients in the TaTME group developed minor LARS, and 21 had major LARS.

CONCLUSION

Sphincter-saving rectal resections are a feasible alternative to APR with good clinical, pathological, and oncological outcomes. Intersphincteric resections and TaTME seem to be equal in terms of clinicopathological results. The functional outcome is yet to be investigated.

TRIAL REGISTRATION

The study was retrospectively registered in Thai Clinical Trials Registry (23-07-2018, ID TCTR20180724001 ).

Liver acquisition with acceleration volume acquisition gadolinium-enhanced magnetic resonance combined with T2 sequences in the diagnosis of local recurrence of rectal cancer

To investigate the efficacy of liver acquisition with acceleration volume acquisition (LAVA) gadolinium-enhanced magnetic resonance (MR) sequences and to assess its added accuracy in diagnosing local recurrence (LR) of rectal cancer with conventional T2-weighted fast spin echo (FSE) sequences. Pelvic MRI, including T2-weighted FSE sequences, gadolinium-enhanced sequences of LAVA and T1-weighted FSE with fat suppression, was performed on 225 patients with postoperative rectal cancer. Two readers evaluated the presence of LR according to "T2" (T2 sequences only), "T2 + LAVA-Gad" (LAVA and T2 imaging), and "T2 + T1-fs-Gad" (T1 fat suppression-enhanced sequence with T2 images). To evaluate diagnostic efficiency, imaging quality with LAVA and T1-fs-Gad by subjective scores and the signal intensity (SI) ratio. In the result, the SI ratio of LAVA was significantly higher than that of T1-fs-Gad (p = 0.0001). The diagnostic efficiency of "T2 + LAVA-Gad" was better than that of "T2 + T1-fs-Gad" (p = 0.0016 for Reader 1, p = 0.0001 for Reader 2) and T2 imaging only (p = 0.0001 for Reader 1; p = 0.0001 for Reader 2). Therefore, LAVA gadolinium-enhanced MR increases the accuracy of diagnosis of LR from rectal cancer and could replace conventional T1 gadolinium-enhanced sequences in the postoperative pelvic follow-up of rectal cancer.

Intersphincteric resection for low rectal cancer

For low rectal cancer located < 5 cm from the anal verge, abdominoperineal resection (APR) with permanent sigmoid colostomy is usually used to ensure the R0 resection. Sphincter saving surgery has emerged in the last 20 years, and the introduction of intersphincteric resection (ISR) can successfully preserve the anal function and guarantee a radical tumor resection for patients with ultra-low lying tumors. Therefore, the use of APR has been consistently declining worldwide. Recently, a growing body of research on ISR has been reported. However, more evidence based results are needed to clarify some issues about ISR. In the current review, we discuss the indications for ISR and the oncological and functional outcomes following the procedure. Some technique issues of ISR are also discussed.

Sphincter saving and abdomino-perineal resections following neoadjuvant chemoradiation in locally advanced low rectal cancer

BACKGROUND

The improvement in surgical techniques alongside neoadjuvant chemoradiation enabled more patients with low rectal cancer to have sphincter preservation.

STUDY AIM

To compare the oncologic and functional outcome in patients with locally advanced low rectal cancer treated by neoadjuvant chemoradiation followed by sphincter saving resection (SSR) against those who underwent abdomino-perineal resection (APR).

PATIENTS AND METHODS

A total of 111 patients with low rectal cancer were included in the study. Sixty-one consented patients who prospectively underwent SSR, from Jan 2008 to Jan 2013, and a retrospective group, formed of 50 patients, selected from cases seen at NCI, with comparable demographic, clinical and pathologic criteria, who underwent APR from Jan 2003 to Jan 2008. All lesions were <5 cm from anal verge. All 111 patients received preoperative chemoradiation and total mesorectal excision.

RESULTS

All tumors were located at a median of 3.6 cm (range 2.5-4.5 cm) for the SSR group, and 3.5 cm (range 2.5-4.6 cm) for the APR group, from the anal verge. The median follow-up was 34 months (range 1-60 months) for both groups. The difference in disease recurrence and OS between the APR and SSR groups were both statistically insignificant.

CONCLUSION

In low rectal cancer, the sphincter preservation appears to have nearly the same oncologic outcome compared to APR, this might be attributed to the small sample size and short follow up period. However, patients with sphincter preservation have certainly demonstrated an indisputable better functional outcome, in terms of stoma avoidance and adequate continence.