Preoperative MRI sphincter morphology and anal manometry: can they be markers of functional outcome following anterior resection for rectal cancer?

Low Anterior Resection Syndrome and Quality of Life of Patients After Sphincter Preservation Surgery: A Prospective Study

Background After anterior resection (AR), one of the most debilitating complications is low anterior resection syndrome (LARS) seen in about 64% of patients. The severity of the LARS score was significantly correlated with neoadjuvant treatment, the extent of rectal surgery, complication by the anastomotic leak, female gender, and age < 64 years. In this study, we analyzed the impact of various clinical factors on LARS and also the various domains of quality of life (QoL). Purpose To assess the incidence of LARS in patients undergoing sphincter-sparing surgery for rectal cancer after the patient starts long-term defecating per anus, change in the QoL, and relation to LARS and factors affecting it. Methods One year before, 72 patients who had undergone AR in the Regional Cancer Centre were interviewed by a trained interviewer and data was collected from the file. The questionnaires used were the Wexner Incontinence score, LARS Malayalam Questionnaire, and European Organisation For Research and Treatment of Cancer (EORTC) QLQ C30 Malayalam translations. Statistical measures The LARS score was used to categorize patients into three grades. The scores were compared with clinical and social factors using the χ2 test for association. Continuous variables were compared by the Spearman Rho test. Results Details of patients were studied (male: 55.6% (40) and female: 44.4% (32)). Fifty patients underwent low anterior resection (LAR). The mean LARS score was 25.61, with 47.2% of patients having severe LARS score. The mean Wexner score was 6.84. The relation with type of surgery, approach (laparoscopic vs open), or type of neoadjuvant therapy was not found to be significant. A higher LARS score did not impact overall QoL as assessed by FACT-C. Insomnia and diarrhea symptoms scores were significantly worsened. The pain score was worse for those undergoing stapler anastomosis. Wexner's score was worse for those who had received adjuvant chemotherapy. Role functioning score was better for AR compared to low anterior resection (LAR). Only distance from the anal verge was found to be a significant cause of LARS and was negatively correlated. Discussion LARS of severe degrees were seen in most patients. No modifiable risk factors were significantly found to affect the chance of LARS. However, LARS did not have a significant impact on QoL, neither did the type of surgery. So sphincter preservation can be offered to the patients, but all patients undergoing LAR should be counseled well about the risk of LARS before surgery.

MRI measurements predict major low anterior resection syndrome in rectal cancer patients

PURPOSE

Current low anterior resection syndrome (LARS) score is lagging behind and only based on clinical symptoms patient described. Preoperative imaging indicators which can be used to predict LARS is unknown. We proposed preoperative MRI parameters for identifying major LARS.

METHODS

Patients receiving curative restorative anterior resection from Sept. 2007 to Sept. 2015 were collected to complete LARS score (median 75.7 months since surgery). MRI measurements associated with LARS were tested, and a multivariate logistic model was conducted for predicting LARS. Receiver operating characteristic curve was used to evaluate the model.

RESULTS

Two hundred fifty-five patients undergoing neoadjuvant chemoradiotherapy and 72 patients undergoing direct surgery were enrolled. The incidence of major LARS in NCRT group was significantly higher (53.3% vs.34.7%, P = 0.005). In patients with neoadjuvant chemoradiotherapy, the thickness of ARJ (TARJ), the distance between the tumor's lower edge and anal rectal joint (DTA), and sex were independent factors for predicting major LARS; ORs were 0.382 (95% CI, 0.198-0.740), 0.653 (95% CI, 0.565-0.756), and 0.935 (95% CI, 0.915-0.955). The AUC of the multivariable model was 0.842 (95% CI, 0.794-0.890). In patients with direct surgery, only DTA was the independent factor for predicting major LARS; OR was 0.958 (95% CI, 0.930-0.988). The AUC was 0.777 (95% CI: 0.630-0.925).

CONCLUSIONS

Baseline MRI measurements have the potential to predict major LARS in rectal cancer, which will benefit the decision-making and improve patients' life quality.

Central perforated VRAM flap and neurostimulated levator augmentation for functional and aesthetical reconstruction after abdominoperineal excision in cancer

BACKGROUND

Preservation of quality of life regarding fecal continence after abdominoperineal excision (APE) in cancer is challenging. Simultaneous soft tissue coverage and restoration of continence mechanism can be provided through an interdisciplinary collaboration of colorectal and plastic reconstructive surgery.

OBJECTIVE

Evaluation of surgical procedure and outcome combining soft tissue reconstruction using a central perforated vertical rectus abdominis myocutaneous flap (VRAM), implementing a perineostoma and restoring anorectal angle augmenting the levator ani by neurostimulated graciloplasty.

METHODS

14 Patients underwent APE due to cancer. In all patients coverage was achieved by pedicled VRAM and simultaneous pull-through descendostomy (perineostoma). 10 of those patients received a levator augmentation additionally. Postoperative complications, functional measures of continence as well as quality of life were obtained.

RESULTS

Perineal minor complication rate was 43% without need of surgical intervention. All but one VRAM survived. Continence measures and disease specific life quality showed a good preservation of continence in most patients.

CONCLUSION

The results present a complex therapy option accomplished by a collaboration of two highly specialized partners (visceral and plastic surgery) after total loss of the sphincter function and consecutive fecal insufficiency after APE.

Anterior resection syndrome: What should we tell practitioners and patients in 2018?

Multidisciplinary management of infra-peritoneal rectal cancer has pushed back the frontiers of sphincter preservation, without impairment of carcinological outcome. However, functional intestinal sequelae, grouping together several symptoms known under the name of anterior resection syndrome (ARS), have emerged and become an increasingly frequent concern for both patients and physicians. The pathophysiology is complex: ARS is a combination in various degrees of stool frequency, incontinence for flatus and/or stools, urgency, and disorders in discrimination and evacuation. The "Low Anterior Resection Score" (LARS), validated in 2012, is currently used to evaluate the severity of ARS and its impact on quality of life. While ARS can show improvement over the first two years, symptoms persist for longer than two years in nearly 60% of patients and in half of these patients, ARS is considered severe. The most frequently reported independent risk factors of severe ARS include neo-adjuvant radiation therapy, the extent of resection (total mesorectal excision that includes inter-sphincteric resection), absence of colonic pouch and anastomotic leak. In the absence of surgical complications and/or local recurrence, physicians can draw from a wide therapeutic armamentarium in order to improve the functional outcome of patients, including diet and lifestyle modifications, gut motility regulators, multimodal rehabilitation (biofeedback, electro-stimulation) and sacral nerve modulation. Permanent colostomy is an alternative of last resort, proposed only when all other solutions fail. A better understanding of the natural history of ARS, its risk factors as well as the array of therapeutic alternatives should provide better patient information and optimize management.

Alterations of anal physiological features after surgery for low rectal cancer and management strategies

The sphincter preserving operation has improved the quality of life (QOL) of patients with low rectal cancer. However, some patients complain of having postoperative fecal incontinence and low QOL due to sphincter injury, nerve injure, and decreased rectal capacity. Therefore, anal physiology evaluation must be done preoperatively, the sphincter muscle and nerve should be preserved in operation, and biofeedback treatment should be administered postoperatively.

MR-FLIP: a new method that combines a functional lumen imaging probe with anatomical information for spatial compliance assessment of the anal sphincter muscles

AIM

Continence results from a complex interplay between anal canal (AC) muscles and sensorimotor feedback mechanisms. The passive ability of the AC to withstand opening pressure - its compliance - has recently been shown to correlate with continence. A functional lumen imaging probe (FLIP) is used to assess AC compliance, although it provides no anatomical information. Therefore, assessment of the compliance specific anatomical structures has not been possible, and the anatomical position of critical functional zones remains unknown. In addition, the FLIP technique assumes a circular orifice cross-section, which has not been shown for the AC. To address these shortcomings, a technique combining FLIP with a medical imaging modality is needed.

METHOD

We implemented a new research method (MR-FLIP) that combines FLIP with MR imaging. Twenty healthy volunteers underwent MR-FLIP and conventional FLIP assessment. MR-FLIP was validated by comparison with FLIP results. Anatomical markers were identified, and the cross-sectional shape of the orifice was investigated.

RESULTS

MR-FLIP provides compliance measurements identical to those obtained by conventional FLIP. Anatomical analysis revealed that the least compliant AC zone was located at the proximal end of the external anal sphincter (EAS). The cross-sectional shape of the AC was found to deviate only slightly from circularity in healthy volunteers.

CONCLUSION

The proposed method is equivalent to classical FLIP. It establishes for the first time direct mapping between local tissue compliance and anatomical structure, which is key to gaining novel insights into (in)continence. In addition, MR-FLIP provides a tool for better understanding conventional FLIP measurements in the AC by quantifying its limitations and assumptions.

Paradoxical puborectalis syndrome on diffusion-weighted imaging: a retrospective study of 72 cases

This study aimed to evaluate the application value of diffusion-weighted imaging (DWI) for assessing paradoxical puborectalis syndrome (PPS) in patients with obstructive defecation syndrome (ODS). The medical records of 72 ODS patients who underwent magnetic resonance (MR)-DWI and MR-defecography were retrospectively reviewed. The differences in the apparent diffusion coefficients (ADCs) and the thickness of the right and left branches of the puborectalis muscles between the PPS(+) and PPS(−) groups were compared. In addition, the absolute within-patient differences between the right and left branches (ADC, thickness) were compared between the two groups. The absolute difference in ADCs (right branch - left branch) was significantly different between the two groups. Regardless of whether the ADC was acquired through single-ROI (0.10 ± 0.08 vs 0.23 ± 0.18, P = 0.000) or multi-ROI (0.16 ± 0.14 vs 0.27 ± 0.17, P = 0.009) analysis, the PPS(+) patients displayed a lower absolute ADC difference than did the PPS(−) patients. However, there was no statistically significant difference in the ADC value, thickness or the absolute difference in thickness between the two groups. These findings suggest that DWI may have value in quantitatively assessing the puborectalis muscle in ODS patients, whereas the value of puborectalis thickness in such aspect needs further study.

Neoadjuvant therapy abolishes the functional benefits of a larger rectal remnant, as measured by magnetic resonance imaging after restorative rectal cancer surgery

BACKGROUND

The combination of advances in surgical technique and neoadjuvant therapy for rectal cancer has resulted in more patients undergoing sphincter-preserving surgery. Unfortunately, numerous patients subsequently experience bowel dysfunction, and may suffer from lifelong severe disability with major impact on their quality of life. The aim of the present study was to investigate whether the risk of severe LARS in patients was associated with the length of remnant rectum.

METHODS

A total of 125 patients who underwent sphincter-preserving surgery for rectal cancer were included. Postoperative bowel function was assessed using the low anterior resection syndrome (LARS) score a minimum of one year following surgery. The length of remnant rectum was measured on postoperative MRI of the pelvis and was correlated with the risk of having major LARS.

RESULTS

Overall, major LARS was observed in 38 per cent of patients. In the patients who underwent surgery alone, major LARS was reported by 27 per cent, and a larger remnant rectum was associated with a better functional outcome. In contrast, 80 per cent of patients who underwent combined preoperative chemoradiotherapy and surgery reported having major LARS. No association between the length of remnant rectum and the risk of major LARS was observed in patients treated with combined neoadjuvant therapy and surgery.

CONCLUSION

Both the length of remnant rectum and preoperative chemoradiotherapy had a major impact on the severity of bowel dysfunction after restorative rectal cancer surgery. No functional benefit from an irradiated rectal remnant was observed.

The relationship of 3-D translabial ultrasound anal sphincter complex measurements to postpartum anal and fecal incontinence

INTRODUCTION AND HYPOTHESIS

We aimed to determine whether anal sphincter complex (ASC) measurements on translabial ultrasound (TL-US) were related to anal incontinence (AI) or fecal incontinence (FI) symptoms 6 months postpartum.

METHODS

A prospective cohort of primiparous women underwent TL-US 6 months after a vaginal birth (VB) or cesarean delivery (CD). Muscle thickness was measured at 3, 6, 9, and 12 o'clock positions of the external anal sphincter (EAS), the same four quadrants of the internal anal sphincter (IAS) at proximal, mid, and distal levels, and at the bilateral pubovisceralis muscle (PVM). Measurements were correlated to AI and FI on the Wexner Fecal Incontinence Scale, with sub-analyses by mode of delivery. The odds ratio (OR) of symptoms was calculated for every 1 mm increase in muscle thickness (E1MIT).

RESULTS

A total of 423 women (299 VB, 124 CD) had TL-US 6 months postpartum. Decreased AI risk was associated with thicker measurements at the 6 o'clock (OR 0.74 E1MIT) and 9 o'clock proximal IAS (OR 0.71 E1MIT) in the entire cohort. For CD women, thicker measurements of the 9 o'clock proximal IAS were associated with decreased risk of AI (OR 0.56 E1MIT) and thicker distal 6 o'clock IAS measurements were related to a decreased risk of FI (OR 0.37 E1MIT). For VB women, no sphincter measurements were significantly related to symptoms, but thicker PVM measurements were associated with increased risk of AI (right side OR 1.32 E1MIT; left side OR 1.21 E1MIT).

CONCLUSIONS

ASC anatomy is associated with AI and FI in certain locations; these locations vary based on the patient's mode of delivery.

Neurostimulated levator augmentation--a new approach in restoring continence

PURPOSE

Restoration of continence remains a major challenge in patients after abdominoperineal rectal excision (APE) or with end-stage fecal incontinence. A new surgical technique, the neurostimulated levator augmentation, was introduced for pelvic floor augmentation using dynamic graciloplasty in order to restore anorectal angulation. The aim of this study was to assess feasibility and efficiency.

METHODS

From November 2009 to March 2014, n = 17 patients underwent neurostimulated levator augmentation (n = 10 after APE, n = 5 intractable idiopathic fecal incontinence, n = 2 traumatic anal amputation). Gracilis muscle was transposed through the obturator foramen into the pelvic cavity, positioned in a U-shaped sling behind the rectum, fixed to the contralateral os pubis to restore anorectal angulation, and then conditioned by neurostimulation. Questionnaires analyzing function and quality of life were administered.

RESULTS

For neurostimulated levator augmentation, four patients suffered from complications that needed operative intervention (n = 3 wound infection, n = 1 colon perforation); three pharmacological treatment and two complications needed no further invasive intervention. One patient died due to causes unrelated to the operation, and no complication required intensive care management. Fecal incontinence in patients with idiopathic incontinence improved significantly after surgery as well as incontinence episodes, urgency, and disease-specific quality of life through all dimensions. Generic quality of life was significantly better after surgery in all patients. After median follow-up of 17 months (2-45), all but one patient would undergo the procedure again.

CONCLUSIONS

Neurostimulated levator augmentation was feasible in all patients with acceptable morbidity. It may represent a new therapeutic option in selected patients with intractable fecal incontinence.

Magnetic resonance imaging in rectal cancer: A surgeon’s perspective

Magnetic resonance imaging (MRI) in rectal cancer was first investigated in 1999 and has become almost mandatory in planning rectal cancer treatment. MRI has a high accuracy in predicting circumferential resection margin involvement and is used to plan neoadjuvant therapy. The accuracy of MRI in assessing mesorectal lymph nodes remains moderate, as there are no reliable criteria to assess nodal involvement. MRI seems to be good in assessing peritoneal involvement in upper rectal cancer; this however has been assessed in only a few studies and needs further research. For low rectal cancers, mesorectum is thin at the level of levator ani especially in relation to prostate; so predicting circumferential resection margin involvement is not easy. However high spatial resolution coronal imaging shows levator muscles, sphincter complex and intersphincteric plane accurately. This is used to stage low rectal tumors and plan plane of surgery (standard surgery, intersphincteric resection, Extralevator abdominoperineal resection). While most centres perform MRI post chemoradiotherapy, its role in accurate staging post neoadjuvant therapy remains debatable. THe role of Diffusion weighted MRI post neoadjuvant therapy is being evaluated in research settings.

Chemoradiotherapy response in recurrent rectal cancer

The efficacy of response to preoperative chemoradiotherapy (CRT) in recurrent versus primary rectal cancer has not been investigated. We compared radiological downsizing between primary and recurrent rectal cancers following CRT and determined the optimal size reduction threshold for response validated by survival outcomes. The proportional change in tumor length for primary and recurrent rectal cancers following CRT was compared using the independent sample t-test. Overall survival (OS) was calculated using the Kaplan–Meier product limit method and differences between survival for tumor size reduction thresholds of 30% (response evaluation criteria in solid tumors [RECIST]), 40%, and 50% after CRT in primary and recurrent rectal cancer groups. A total of 385 patients undergoing CRT were analyzed, 99 with recurrent rectal cancer and 286 with primary rectal cancer. The mean proportional reduction in maximum craniocaudal length was significantly higher for primary rectal tumors (33%) compared with recurrent rectal cancer (11%) (P < 0.01). There was no difference in OS for either primary or recurrent rectal cancer when ≤30% or ≤40% definitions were used. However, for both primary and recurrent tumors, significant differences in median 3-year OS were observed when a RECIST cut-off of 50% was used. OS was 99% versus 77% in primary and 100% versus 42% in recurrent rectal cancer (P = 0.002 and P = 0.03, respectively). Only patients that demonstrated >50% size reduction showed a survival benefit. Recurrent rectal cancer appears radioresistant compared with primary tumors for tumor size after CRT. Further investigation into improving/intensifying chemotherapy and radiotherapy for locally recurrent rectal cancer is justified.