Anal Sphincter Involvement Research Articles

Case report: Perineal swelling: A rare case of scar endometriosis.

We report a rare case of episiotomy site scar endometriosis manifested as painful perineal swelling near the anus for 2 years affecting daily routine activity, especially during menses. A 33-year-old female, para 2 with both vaginal deliveries with last child birth 8 years back. A 2.5 × 3 cm firm, tender nodule was present on the posterior vulva at the right mediolateral episiotomy site. Trans-perineal and trans-anal ultrasound scan was done, anal sphincter involvement was ruled out and the nodule was excised with free margins. histopathology confirmed the diagnosis of scar endometriosis. The key takeaway from this case is endometriosis can present after 8 years of vaginal delivery. The timely diagnosis and treatment is necessary as delay may cause anal sphincter involvement or malignant transformation.

Pelvic Diameter is not Associated with Positive Circumferential Resection Margin in Rectal Cancer: Retrospective Analysis of 78 Cases

Abstract Objective To identify if there is an association between pelvic entry and pelvic outlet diameters with increased positive circumferential resection margin (CRM) in rectal cancer. Introduction Positive CRM in rectal cancer is a major predictor for local and distant recurrence. Pelvic diameters may be related to the difficulty of dissection, as well as intrinsic tumor characteristics such as tumor size, location, distance from the anal margin, and T stage, which may compromise the integrity of the mesorectum and circumferential margin involvement. Methods A retrospective review of the patient's medical records who underwent surgical resection of rectal adenocarcinoma from January 2012 to June 2022 was performed. The patient's preoperative staging, operative characteristics, and histopathologic outcomes were gathered from the medical records. Preoperative MRI scanning was done in all patients. MRI pelvimetry was done by two observers. CRM involvement was recorded as stated in the pathology report. Pelvimetry variables were dichotomized according to their mean values for correlation analysis. The odds ratio (OR) was calculated from a binary logistics regression model to assess the relation between the positive CRM and the independent variables. Results A total of 78 patients were included in this study. A positive CRM was reported in 10 patients (12.8%). BMI >27.4 + 6.6 (p = 0.02), positive extramural vascular invasion (p = 0.027), positive CRM by MRI scanning (p = 0.004), and anal sphincter involvement (p = 0.03) were associated with positive CRM. Pelvimetry values were not associated with a positive CRM. Conclusion No association was found between the pelvic diameters measured by MRI pelvimetry with a positive CRM.

Low Rectal Cancers at Initial Staging MRI.

Low rectal cancers, which are associated with increased risk of local recurrent disease and poorer prognosis, have unique anatomic considerations and issues for staging and treatment that do not apply to mid and high rectal cancers. Although tumor histology help drive the staging and treatment of all rectal cancers, it is of particular importance in low rectal cancers, which may involve the anal canal, to help establish whether a low rectal mass should be staged and treated as a rectal cancer (ie, adenocarcinoma) or an anal cancer (ie, squamous cell carcinoma). Optimal staging and treatment of rectal cancer are contingent on tumor location and local extent, which help guide management decisions including neoadjuvant therapy and curative surgical treatment strategies. Tumor location in the low rectum and local involvement of the anal canal, sphincter, and pelvic floor help determine whether a patient can undergo sphincter-preserving resection such as a low anterior resection versus abdominoperineal resection to achieve negative surgical margins. Issues exist related to the anatomy and patterns of disease spread that are unique to the low rectum and include how to determine and stage anal sphincter involvement, mesorectal fascia status at the pelvic floor, and nodal status of extramesorectal nodes such as the external iliac and inguinal lymph nodes. For these reasons, it is imperative that radiologists who interpret rectal cancer staging MRI examinations feel comfortable with the unique anatomy of the low rectum and anal canal, nuances of low rectal cancer local disease spread, and treatment paradigms for low rectal cancer. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center. See the invited commentary by Gollub in this issue.

THeragnostic utilities for neoplastic DisEases of the rectum by MRI guided radiotherapy (THUNDER 2) phase II trial: interim safety analysis

BackgroundThe THUNDER-2 phase II single institutional trial investigates the benefits of MRI-guided radiotherapy (MRIgRT) in treating locally advanced rectal cancer (LARC). This study focuses on evaluating the impact of escalating radiation therapy dose in non-responder patients using the Early Tumour Regression Index (ERI) for predicting complete response (CR). The trial’s primary endpoint is to increase the CR rate in non-responders by 10% and assess the feasibility of the delta radiomics-based MRIgRT predictive model. This interim analysis assesses the feasibility and safety of the proposed MRIgRT dose escalation strategy in terms of acute toxicity (gastrointestinal, genitourinary and haematological) and treatment adherence.MethodsStage cT2-3, N0-2, or cT4 patients with anal sphincter involvement, N0-2a, M0, but without high-risk features were enrolled. MRIgRT treatment consisted of a standard dose of 55 Gy to the Gross Tumor Volume (GTV) and mesorectum, and 45 Gy to the mesorectum and drainage nodes in 25 fractions with concomitant chemotherapy. 0.35 T MRI was used for simulation imaging and daily alignment. ERI was calculated at the 10th fraction. Non-responders with an ERI above 13.1 received intensified dose escalation from the 11th fraction, resulting in a total dose of 60.1 Gy. Acute toxicity was assessed using the CTCAE v.5 scale.ResultsFrom March 2021 to November 2022, 33 out of the total number of 63 patients to be enrolled (52.4%) were included, with one withdrawal unrelated to treatment. Sixteen patients (50%) underwent dose escalation. Treatment was well tolerated, with only one patient (3.1%) in the standard treatment group experiencing acute Grade 3 diarrhea, proctitis, and cystitis. No significant differences in toxicity were observed between the two groups (p = 0.5463).ConclusionsMRIgRT treatment with dose escalation up to 60.1 Gy is well tolerated in LARC patients predicted as non-responders by ERI, confirming the feasibility and safety of this approach. The THUNDER-2 trial’s primary and secondary endpoints will be fully analyzed when all planned patients will be enrolled.

Outcomes of Watch and Wait Following Total Neoadjuvant Therapy for Rectal Cancer

To evaluate the outcomes of patients with locally advanced rectal cancer who achieved a clinical complete response (cCR) after total neoadjuvant therapy and enrolled in a prospective watch and wait (WW) database. Consecutive patients with locally advanced rectal cancer who achieved cCR following total neoadjuvant therapy (long-course chemoradiotherapy plus systemic chemotherapy) and were enrolled in our institutional WW surveillance protocol from 2014 through 2022 with the intention of organ preservation. Patients with lack of follow up according to our institutional protocol were excluded. Primary outcomes included local tumor regrowth and distant metastatic disease recurrence. Thirty-three consecutive patients (48% male; median age 61 [33-77] years) with the diagnosis of locally advanced rectal adenocarcinoma were managed by a multidisciplinary team. All patients had Eastern Cooperative Oncology Group Performance Status score of 0 or 1 at time of rectal cancer diagnosis. Location of tumor included upper rectum (18%), middle rectum (40%), and lower rectum (42%). On initial staging magnetic resonance imaging, 4 (12%) patients had evidence of extramural venous invasion, 6 (18%) had a threatened mesorectal margin, and 4 (12%) had anal sphincter or levator ani tumor involvement. A majority (61%) received chemotherapy followed by long-course chemoradiotherapy. Only one patient had an unplanned break during radiotherapy. Local tumor regrowth was diagnosed in 4 (12%) patients and all underwent successful salvage surgery without additional local failures at a median follow-up of 19 [12-48] months. Two of these four patients remain disease-free at a median follow-up time of 12.5 months. Mean time to local tumor regrowth as first site of cancer recurrence was 33.5 [18-46] months. Distant metastatic disease as the first site of recurrence occurred two patients (6%). Mean time to distant metastatic disease as first site of recurrence was 27 months. Only one mortality occurred in the entire group at a median follow-up of 49 [8-102] months. Organ preservation after total neoadjuvant therapy for locally advanced rectal cancer yields excellent outcomes with low local and distant relapse rates. Structured surveillance protocols and multidisciplinary care are essential for success.

The role of magnetic resonance tumour regression grade in the prediction of regression and survival of rectal adenocarcinoma after long-course chemoradiotherapy: a cohort study.

Between 2011 and 2016, patients with rectal cancer who underwent LCCRT and had post-LCCRT MRI were included in the study. Both mrTRG and pTRG were dichotomised into good responders (mrTRG 1-3 and pTRG 0-1) and poor responders (mrTRG 4-5 and pTRG 2-3). Correlation between mrTRG and pTRG was assessed with Cohen κ analysis. Survival analysis was performed with Kaplan-Meier test and Cox proportional hazard models. There were 59 patients included in this study. There were significant reductions in anal sphincter and circumferential resection margin involvement in post-LCCRT MRI. Fair agreement was found between mrTRG and pTRG (κ=0.345). Sensitivity, specificity and accuracy of mrTRG 1-3 to predict good pathological response were 100%, 46.3% and 62.7%, respectively. On survival analysis, mrTRG 1-3 was not associated with improved overall survival and recurrence-free survival. While there is fair agreement in correlation between mrTRG and pTRG, MRI remains an objective, noninvasive assessment of tumour response. Further studies are required to improve the ability of mrTRG to predict good responders to LCCRT and evaluate its role as a prognostic marker for survival.

Clinical presentation of perineal endometriosis and prognostic nomogram after surgical resection

BackgroundThis retrospective study evaluated the clinical features of perineal endometriosis (PEM) and established a prognostic nomogram for recurrence probability in patients treated with surgical resection.MethodsThis study enrolled 130 PEM patients who had received surgical treatment in Peking Union Medical College Hospital (PUMCH) between January 1992 and September 2020. We collected their clinical features and conducted outpatient or telephone follow-up. The predictive nomogram was constructed based on 104 patients who had completed follow-up by July 2021. The Cox proportional hazards regression model was used to evaluate the prognostic effects of multiple clinical parameters on recurrence. The Index of concordance (C-index) and calibration curves were used to access the discrimination ability and predictive accuracy of the nomogram respectively, and the results were further validated via bootstrap resampling. Calculating the area under the curve (AUC) via risk scores of patients aimed to further access the predictive power of the model. In addition, the survival curve was depicted using Kaplan–Meier plot and compared by log-rank method.ResultsMost PEM patients had been symptomatic for 24–48 months before the lesion resection. With a median 99.00 (interquartile range: 47.25–137.50) months of postoperative observation, there were 16 (15.1%) out of 104 cases who finished follow-up reported symptomatic recurrence. On multivariate analysis of derivation cohort, multiple lesions, microscopically positive margin (mPM) and anal sphincter involvement (ASI) were selected into the nomogram. The C-index of the nomogram for predicting recurrence was 0.84 (95% CI 0.77–0.91). The calibration curve for probability of recurrence for 36, 60 and 120 months showed great agreement between prediction by nomogram and actual observation. Furthermore, the AUCs of risk score for 36, 60 and 120 months were 0.89, 0.87 and 0.82 respectively.ConclusionsPEM is a rare kind of endometriosis and surgery is the primary treatment. Multiple lesions and ASI are independent risk factors for postoperative recurrence, and wide resection with more peripheral tissue could be preferred. The proposed nomogram resulted in effective prognostic prediction for PEM patients receiving surgical excision. In addition, this predictive nomogram needs external data sets to further validate its prognostic accuracy in the future.

Dentate line invasion as a predictive factor of poor distant relapse-free survival in locally advanced lower rectal cancer with anal sphincter involvement

BackgroundWhile an important surgical landmark of the dentate line has been established for locally advanced lower rectal cancer (LALRC), the prognostic significance of dentate line invasion (DLI) has not been well defined. This study aimed to explore the impact of DLI on prognosis in LALRC patients with anal sphincter involvement after neoadjuvant chemoradiotherapy followed by surgery.MethodsWe analyzed 210 LALRC patients and classified them into DLI group (n = 45) or non-DLI group (n = 165). The exact role of DLI in survival and failure patterns was assessed before and after propensity-score matching(PSM). Finally, 50 patients were matched.ResultsBefore matching, patients in the DLI group had poorer 5-year distant relapse-free survival (DRFS) (P < 0.001), disease-free survival (DFS) (P < 0.001), and overall survival (OS) (P = 0.022) than those in the non-DLI group, with the exception of local recurrence-free survival (LRFS) (P = 0.114). After PSM, the 5-year DRFS, DFS, OS, and LRFS were 51.7% vs. 79.8%(P = 0.026), 51.7% vs. 79.8%(P = 0.029), 71.6% vs. 85.4%(P = 0.126), and 85.7% vs. 92.0%(P = 0.253), respectively, between the two groups. DLI was also an independent prognostic factor for poor DRFS with (Hazard ratio [HR] 3.843, P = 0.020) or without matching (HR 2.567, P = 0.001). The DLI group exhibited a higher rate of distant metastasis before (44.4% vs. 19.4%, P < 0.001) and after matching (48.0% vs. 20.0%, P = 0.037) and similar rates of locoregional recurrence before (13.3% vs.7.9%, P = 0.729) and after matching (16.0% vs.12.0%, P = 1.000).ConclusionsDLI may portend worse DRFS and distant metastasis in LALRC patients with anal sphincter involvement, and this may be an important variable to guide clinicians.

Total Neoadjuvant Therapy Is a Predictor for Complete Pathological Response in Patients Undergoing Surgery for Rectal Cancer

IntroductionTotal neoadjuvant therapy (TNT) is a new therapeutic strategy in patients with rectal cancer. We examined the role of TNT, in addition to other pre-operative factors, as a predictor for pathologic complete response (pCR). MethodsA retrospective analysis of all rectal cancer patients who underwent surgery between 2016 and 2021 was conducted. Patients were classified into two groups—pCR group and residual tumor group. Patient data were reviewed and entered into univariate and multivariate analyses to determine predictors of pCR. ResultsA total of 172 patients were treated with neoadjuvant therapy and underwent surgery during the study period. Sixty patients (34.9%) were treated with TNT while 112 (65.1%) were treated with traditional neoadjuvant chemoradiation. The overall pCR rate was 25.6% (44 patients), with 31.6% (19 patients) in patients who received TNT compared to 22.3% (25 patients) in patients who received neoadjuvant chemoradiation (NCRT). Univariate analysis of clinical and radiological factors correlated with pCR demonstrated no significant differences between the two groups in cT stage (p = 0.46), cN stage (p = 0.52), positive circumferential resection margin (CRM) (p = 0.72), tumor location (p = 0.35), symptomatic presentation (p = 0.09), and anal sphincter involvement (p = 0.68). Multivariate logistic analysis demonstrated that only pre-operative TNT (OR:2.35; 95% CI 1.06–5.25; p = 0.03) was predictive of pCR, while extramural vascular invasion (EMVI) was a predictor for lower rates of pCR (OR: 0.28; 95% CI 0.09–0.9; p = 0.03). ConclusionRectal cancer patients undergoing TNT prior to surgery have a higher chance of developing a complete pathologic response. Evaluation of this therapy should be continued and extended to larger numbers of patients to see if the differences we observed are real.

Preoperative MRI accuracy after neoadjuvant chemoradiation for locally advanced rectal cancer.

To evaluate the performance of magnetic resonance imaging (MRI) in restaging locally advanced rectal cancers (LARC) after neoadjuvant chemoradiotherapy (nCRT), with pathologic correlation. 80 patients with LARC treated with neoadjuvant therapy, with restaging MRI and surgery, were enrolled and prospectively reviewed. The diagnostic accuracy of the restaging MRI was assessed for tumor (ymrT), nodal status (ymrN), circumferential resection margin (ymrCRM), extramural vascular invasion (ymrEMVI) and tumoral deposits (ymrN1c) by calculating the sensitivity (Se), specificity (Sp), negative predictive values (NPV) and positive predictive values (PPV). Response to treatment was classified as good response (complete/near complete) vs. poor response (poor/partial response). The agreement between the tumor regression grade at MRI (mrTRG) and pathology (pTRG) was reported, as well the performance of mrTRG to identify good responders. The correlation between restaging MRI and histopathology was assessed by Spearman correlation coefficient. The MRI accuracy ranged between 63.8% and 92.5% for T stage and was 81.3% for N stage. All MRI parameters evaluated at restaging were statistically significant correlated with histopathology evaluation, but EMVI. There was moderate correlation for N and N1c and a positive strong correlation for T, CRM and TRG (Spearman correlation coefficient of 0.390 for mrN1c-pN1c, 0.428 for mrN-pN, 0.522 for mrCRM-pCRM, 0.550 for mrT-pT and 0.731 for mrTRG-pTRG). Diagnostic accuracy of anal sphincter invasion was 91.3%, with a negative predictive value (NPV) of 100%. Accuracy rate varied between 70% for partial response to 93.75% for complete response after nCRT. MR imaging had good accuracy in restaging LARCs after nCRT. Our results showed high MRI accuracy in detecting anal sphincter involvement for low rectal tumors, with high NPV to exclude tumoral invasion. Restaging MRI predicted well the tumor regression grade, with good diagnostic performance in differentiating good responders from poor/partial responders. The accuracy was high for detecting complete response.

THUNDER 2: THeragnostic Utilities for Neoplastic DisEases of the Rectum by MRI guided radiotherapy

BackgroundNeoadjuvant chemoradiation therapy (nCRT) is the standard treatment modality in locally advanced rectal cancer (LARC). Since response to radiotherapy (RT) is dose dependent in rectal cancer, dose escalation may lead to higher complete response rates. The possibility to predict patients who will achieve complete response (CR) is fundamental. Recently, an early tumour regression index (ERI) was introduced to predict pathological CR (pCR) after nCRT in LARC patients.The primary endpoints will be the increase of CR rate and the evaluation of feasibility of delta radiomics-based predictive MRI guided Radiotherapy (MRgRT) model.MethodsPatients affected by LARC cT2-3, N0-2 or cT4 for anal sphincter involvement N0-2a, M0 without high risk features will be enrolled in the trial. Neoadjuvant CRT will be administered using MRgRT. The initial RT treatment will consist in delivering 55 Gy in 25 fractions on Gross Tumor Volume (GTV) plus the corresponding mesorectum and 45 Gy in 25 fractions on the drainage nodes. Chemotherapy with 5-fluoracil (5-FU) or oral capecitabine will be administered continuously.A 0.35 Tesla MRI will be acquired at simulation and every day during MRgRT. At fraction 10, ERI will be calculated: if ERI will be inferior than 13.1, the patient will continue the original treatment; if ERI will be higher than 13.1 the treatment plan will be reoptimized, intensifying the dose to the residual tumor at the 11th fraction to reach 60.1 Gy.At the end of nCRT instrumental examinations are to be performed in order to restage patients. In case of stable disease or progression, the patient will undergo surgery. In case of major or complete clinical response, conservative approaches may be chosen. Patients will be followed up to evaluate toxicity and quality of life.The number of cases to be enrolled will be 63: all the patients will be treated at Fondazione Policlinico Universitario A. Gemelli IRCCS in Rome.DiscussionThis clinical trial investigates the impact of RT dose escalation in poor responder LARC patients identified using ERI, with the aim of increasing the probability of CR and consequently an organ preservation benefit in this group of patients.Trial registrationClinicalTrials.gov Identifier: NCT04815694 (25/03/2021).

Evolutions in rectal cancer MRI staging and risk stratification in The Netherlands

PurposeTo analyze how the MRI reporting of rectal cancer has evolved (following guideline updates) in The Netherlands.MethodsRetrospective analysis of 712 patients (2011–2018) from 8 teaching hospitals in The Netherlands with available original radiological staging reports that were re-evaluated by a dedicated MR expert using updated guideline criteria. Original reports were classified as “free-text,” “semi-structured,” or “template” and completeness of reporting was documented. Patients were categorized as low versus high risk, first based on the original reports (high risk = cT3-4, cN+, and/or cMRF+) and then based on the expert re-evaluations (high risk = cT3cd-4, cN+, MRF+, and/or EMVI+). Evolutions over time were studied by splitting the inclusion period in 3 equal time periods.ResultsA significant increase in template reporting was observed (from 1.6 to 17.6–29.6%; p < 0.001), along with a significant increase in the reporting of cT-substage, number of N+ and extramesorectal nodes, MRF invasion and tumor-MRF distance, EMVI, anal sphincter involvement, and tumor morphology and circumference. Expert re-evaluation changed the risk classification from high to low risk in 18.0% of cases and from low to high risk in 1.7% (total 19.7%). In the majority (17.9%) of these cases, the changed risk classification was likely (at least in part) related to use of updated guideline criteria, which mainly led to a reduction in high-risk cT-stage and nodal downstaging.ConclusionUpdated concepts of risk stratification have increasingly been adopted, accompanied by an increase in template reporting and improved completeness of reporting. Use of updated guideline criteria resulted in considerable downstaging (of mainly high-risk cT-stage and nodal stage).Graphic abstract

Sphincter damage during fistulotomy for perianal fistulae and its relationship with faecal incontinence

BackgroundThe length of sphincter which can be divided during fistulotomy for perianal fistula is unclear. The aim was to quantify sphincter damage during fistulotomy and determine the relationship between such damage with symptoms and severity of faecal incontinence and long-term quality of life (QOL).MethodsA prospective cohort study was performed over a 2-year period. Patients with intersphincteric and mid to low transsphincteric perianal fistulas without risk factors for faecal incontinence were scheduled for fistulotomy. All patients underwent 3D endoanal ultrasound (3D-EAUS) pre-operatively and 8 weeks postoperatively. Measurements were taken of pre- and postoperative anal sphincter involvement and division. Anal continence was assessed using the Jorge-Wexner scale and QOL scores pre, 6 and 12 months postoperatively.ResultsForty-nine patients were selected. A strong correlation between pre- and postoperative measurements was found p < 0.001. A median length of 41% of the external anal sphincter and 32% of the internal anal sphincter was divided during fistulotomy. Significant differences in mild symptoms of anal continence were found with increasing length of external anal sphincter division. But there was no significant deterioration in continence, soiling, or quality of life scores at the 1-year follow-up. Division of over two-thirds of the external anal sphincter was associated with the highest incontinence rates.Conclusions3D-EAUS is a valuable tool for quantifying the extent of sphincter involvement pre- and postoperatively. Post-fistulotomy faecal incontinence is mild and increases with increasing length of sphincter division but does not affect long-term quality of life.

Proktoginekologia – kto powinien leczyć? Propozycja algorytmu postępowania

Proctogyneacology deals with conditions involving the anal canal, anal sphincter muscles, rectum, rectovaginal septum, and the female reproductive tract. They may be due to sagging of the pelvic floor and the rectovaginal septum (rectal, vaginal or uterine prolapse, enterocele and rectocele), perinatal injury, including sphincter damage, rectovaginal fistulas, endometriosis with anal sphincter and rectovaginal septum involvement, proctological inflammatory diseases in pregnancy, as well as radiation-induced rectal damage after gynaecological cancer treatment. There are no set guidelines defining which specialist should operate on these patients. We attempted to systematise this issue in the form of an algorithm. An interdisciplinary dialogue allowing for our professional development and, most of all, therapeutic success and reduced risk of postoperative complications, seems to be crucial.

Improving staging of rectal cancer in the pelvis: the role of PET/MRI.

The role of positron emission tomography/magnetic resonance (PET/MR) in evaluating the local extent of rectal cancer remains uncertain. This study aimed to investigate the possible role of PET/MR versus magnetic resonance (MR) in clinically staging rectal cancer. This retrospective two-center cohort study of 62 patients with untreated rectal cancer investigated the possible role of baseline staging PET/MR versus stand-alone MR in determination of clinical stage. Two readers reviewed T and N stage, mesorectal fascia involvement, tumor length, distance from the anal verge, sphincter involvement, and extramural vascular invasion (EMVI). Sigmoidoscopy, digital rectal examination, and follow-up imaging, along with surgery when available, served as the reference standard. PET/MR outperformed MR in evaluating tumor size (42.5 ± 21.03mm per the reference standard, 54 ± 20.45mm by stand-alone MR, and 44 ± 20mm by PET/MR, P = 0.004), and in identifying N status (correct by MR in 36/62 patients [58%] and by PET/MR in 49/62 cases [79%]; P = 0.02) and external sphincter infiltration (correct by MR in 6/10 and by PET/MR in 9/10; P = 0.003). No statistically significant differences were observed in relation to any other features. PET/MR provides a more precise assessment of the local extent of rectal cancers in evaluating cancer length, N status, and external sphincter involvement. PET/MR offers the opportunity to improve clinical decision-making, especially when evaluating low rectal tumors with possible external sphincter involvement.

Clinical Relevance and Practical Approach for Challenging Rectal Cancer MRI Findings

MRI is the standard of care for clinical staging of rectal cancer, but has limitations. The purpose of this review is to describe and simplify the clinical relevance of common challenging findings on rectal cancer MRI, and to outline a practical approach to these findings for radiologists. Recent literature regarding T2 versus T3 stages, extramural depth of invasion, circumferential resection margin/mesorectal fascia involvement, anal sphincter involvement, anterior peritoneal reflection involvement, extramural vascular invasion, and lymph node involvement are reviewed. These findings are structured by the surgical implications, oncological implications, and prognostic implications, with a practical approach summary for each finding. The clinical implications of common challenging rectal cancer MRI findings are summarized with up-to-date supporting evidence and useful suggestions for practicing radiologists.

Accuracy of high-resolution rectal magnetic resonance imaging re-staging with histopathology in locally advanced rectal cancer after neoadjuvant chemoradiotherapy

Background/objectiveRe-staging of locally advanced rectal cancer (LARC) following neoadjuvant chemoradiotherapy (NCRT) is a crucial step in surgical decision-making. Currently, MRI is the imaging of choice for evaluation of LARCs, however, the diagnostic accuracy of this modality is inconsistent. In this study, we evaluated the diagnostic accuracy of MRI in LARC and analyzed the factors that influenced the accuracy. MethodsThe records of 133 patients diagnosed with LARC who were operated on during 2011–2018 were retrospectively reviewed. All patients received NCRT followed by re-staging based on high-resolution rectal MRI. The MRI results were analyzed for their yT and yN accuracy and anal sphincter involvement and compared with the related histopathological studies after definitive surgery. ResultsRe-staging MRIs gave overall accuracy in both the yT stage and yN evaluation of 85% (K 0.45 and 0.21, respectively). The MRI tended to overstaging for tumor invasion and understaging for lymph node involvement (sign test p-values = 0.017 and 0.022, respectively.) The highest accuracy of the yT stage was yT4b (93%, K 0.71). The study found that larger tumors (>3 cm) were associated with significantly higher accuracy in the yT readings while lack of lymphovascular invasion was associated with higher accuracy in the yN readings. The negative predictive value for anal sphincter involvement was 100%. ConclusionMRI has limited accuracy in post-NCRT re-staging in LARC, tending to give overstaged yT readings and understaged yN readings. An MRI exclusion of sphincteric involvement is highly reliable.

Characteristics and long-term outcomes of perineal endometriosis: A retrospective study.

To summarize the clinical features, diagnosis, and treatments of perineal endometriosis (PEM).We retrospectively studied the clinical data of 35 patients with PEM between April 2012 and December 2018 in West China Second Hospital. Patients were divided into the gonadotropins releasing hormone (GnRH) agonist group and non-GnRH agonist group.The main clinical symptom was vulvar painful swellings related to menstrual cycles. Thirty-three patients’ lesions (94.29%) were on the episiotomy scar while 1 case was at the opposite side of the scar. We even found 1 nullipara was diagnosed as PEM. Ten patients (28.57%) were found with anal sphincter involvement. All patients received complete excision of PEM. The recurrence rate of GnRH agonist group was 7.69% (1/13), while the rate of non-GnRH agonist group was 18.75% (3/16).Most PEM was associated with episiotomy history, but PEM could also exist in nullipara. Complete excision of PEM was inevitable. The effect of GnRH agonist on recurrence of PEM needs further studies.

Laparoscopic Posterior Pelvic Exenteration (Complete and Supralevator) for Locally Advanced Adenocarcinoma of the Rectum in Females: Surgical Technique and Short-Term Outcomes.

Background: Laparoscopic posterior exenteration (total and supralevator) is a complex and rarely done procedure. In this study we describe the surgical technique and short-term perioperative outcomes in 7 female patients of locally advanced carcinoma rectum operated with laparoscopic pelvic exenteration. Materials and Methods: We report 7 cases of carcinoma rectum involving either posterior wall of the uterus or vagina, which were operated with a laparoscopic procedure. All perioperative and intraoperative data were collected retrospectively from prospectively maintained electronic data. Results: Nine female patients with the diagnosis of nonmetastatic locally advanced lower rectal adenocarcinoma were selected. In MRI 4 patients had uterus-cervix involvement and 3 patients had a posterior vaginal wall and anal sphincter involvement. Four patients were operated with laparoscopic supralevator posterior exenteration and 3 patients were operated with laparoscopic complete posterior exenteration. Three patients underwent vaginal reconstruction, which was done with bilateral V-Y plasty. All 7 patients received neoadjuvant chemoradiotherapy (NACTRT), 3 patients also received additional chemotherapy (CAPOX regimen) due to poor response to NACTRT. Mean body mass index (BMI) was 23.85 (range 19-27.20). Mean duration for complete posterior exenteration was 9.63 hours (range 7-12 hours). Mean duration for supralevator posterior exenteration was 6.81 hours (range 6.25-7.5 hours). The mean postoperative stay was 10.71 days (range 7-16 days). Mean blood loss was 700 mL (range 200-1800 mL). On postoperative histopathology, all margins were free of tumor in all cases. Conclusion: Laparoscopic approach for locally advanced carcinoma rectum in female patients is feasible with less morbidity and safe short-term oncological outcomes. Careful selection of patients based on MRI is a must before undertaking the minimally invasive surgery approach. Long-term outcomes are still unknown and will require long-term follow-up.

Transanal total mesorectal excision (taTME) for rectal cancer: beyond the learning curve.

Transanal total mesorectal excision (taTME) is a surgical approach for low rectal cancer with a learning curve estimated at 40-50 cases. The experience among taTME surgeons beyond their learning curve is limited. A retrospective analysis of all taTME cases performed for rectal cancer at two tertiary care hospitals from 2014 to 2019 was conducted. Transanal surgeons had previously performed > 50 taTME cases. Demographic, perioperative, and short-term outcomes were analyzed. Among 54 taTME patients, 74.1% were male and 27.8% had a BMI ≥ 30. Tumors were stage I (8), II (13), III (29), and IV (4). Complex cases included 4 local recurrences, 4 prior liver resections, and 2 with prior prostate cancer. Thirty tumors were located ≤ 6cm from the anal verge. On staging MRI, 12 had a positive predicted circumferential radial margin (+CRM), and 4 had internal anal sphincter involvement (+IAS). Forty-seven patients received neoadjuvant therapy. A 2-team approach was used in 51 patients with laparoscopic (83.3%) or robotic (16.7%) abdominal assistance with a 9.2% conversion rate. Low anterior resection with sphincter salvage was achieved in 87% with 8 patients requiring intersphincteric resection. Anastomoses were hand-sewn in 57.4% and all patients were diverted. Median LOS was 5days with a 42.6% 30-day morbidity rate and 3 postoperative mortalities (ARDS, pulmonary embolism and pseudomembranous colitis). Complete and near complete TME grade was achieved in 94.4% with a 3.7% rate of +CRM. At a median follow-up of 28months, local and distant recurrence rates were 3.9% and 17.6%, respectively, with no cancer-related mortality. Indications for taTME at experienced centers have expanded to include complex reoperative cases, local recurrences, metastatic cancer, and tumors with threatened CRM or IAS with evidence of post-treatment tumor regression. In the latter cases, taTME achieves good short-term outcomes and may facilitate R0 resection.