Mesorectal Fascia Involvement Research Articles

The role of superior hemorrhoidal vein ectasia in the preoperative staging of rectal cancer.

The prognosis of colorectal cancer has continuously improved in recent years thanks to continuous progress in both the therapeutic and diagnostic fields. The specific objective of this study is to contribute to the diagnostic field through the evaluation of the correlation between superior hemorrhoidal vein (SHV) ectasia detected on computed tomography (CT) and Tumor (T), Node (N), and distant metastasis (M) examination and mesorectal fascia (MRF) invasion in the preoperative staging of rectal cancer. Between January 2018 and April 2022, 46 patients with histopathological diagnosis of rectal cancer were retrospectively enrolled, and the diameter of the SHV was evaluated by CT examination. The cutoff value for SHV diameter used is 3.7mm. The diameter was measured at the level of S2 during portal venous phase after 4× image zoom to reduce the interobserver variability. The parameters evaluated were tumor location, detection of MRF infiltration (defined as the distance < 1mm between the tumor margins and the fascia), SHV diameter, detection of mesorectal perilesional lymph nodes, and detection of metastasis. A total of 67.39% (31/46) of patients had SHV ectasia. All patients with MRF infiltration (4/46, 7.14%) presented SHV ectasia (average diameter of 4.4mm), and SHV was significantly related with the development of liver metastases at the moment of primary staging and during follow-up. SHV ectasia may be related to metastasis and MRF involvement; therefore, it could become a tool for preoperative staging of rectal cancer.

Clinical outcomes of neoadjuvant chemoradiotherapy followed by total mesorectal excision in locally advanced rectal cancer with mesorectal fascia involvement.

For the treatment of locally advanced rectal cancer (LARC), research on primary lesions with mesorectal fascia (MRF) involvement is lacking. This study analyzed the clinical outcomes and efficacy of dose-escalated neoadjuvant concurrent chemoradiotherapy (NCRT) to patients with LARC involving MRF. We retrospectively reviewed 301 patients who were diagnosed with LARC involving MRF and underwent NCRT followed by total mesorectal excision (TME). Patients who received radiotherapy (RT) doses of ≤50.4 Gy were defined as the non-boost group, while ≥54.0 Gy as the boost group. Pathological tumor response and survival outcomes, including intrapelvic recurrence-free survival (IPRFS), distant metastases-free survival (DMFS) and overall survival (OS), were analyzed. A total of 269 patients (89.4%) achieved a negative pathological circumferential resection margin and 104 (34.6%) had good pathological tumor regression grades. With a median follow-up of 32.4 months, IPRFS, DMFS, and OS rates at 5-years were 88.6%, 78.0%, and 91.2%, respectively. In the subgroup analysis by RT dose, the boost group included more advanced clinical stages of patients. For the non-boost group and boost group, 5-year IPRFS rates were 90.3% and 87.0% (p = 0.242), 5-year DMFS rates were 82.0% and 71.3% (p = 0.105), and 5-year OS rates were 93.0% and 80.6% (p = 0.439), respectively. Treatment related toxicity was comparable between the two groups (p = 0.211). Although this retrospective study failed to confirm the efficacy of dose-escalated NCRT, favorable IPRFS and pathological complete response was achieved with NCRT followed by TME. Further studies combining patient customized RT dose with systemic therapies are needed.

Results of a prospective phase II study of total neoadjuvant therapy for locally advanced rectal cancer.

147 Background: Total neoadjuvant therapy is further accepted for the treatment of locally advanced rectal cancer, which is more valuable for patients with high-risk factors. Optimal schedule of radiotherapy and chemotherapy remains unknown and needs further exploration. Methods: We conducted a multicenter, randomized, phase II trial (ClinicalTrials.gov No.: NCT04543695). Patients aged 18-75 years with initial stage II / III rectal adenocarcinoma (At least one of high-risk factors should be included: mesorectal fascia involvement, T4, N2, positive lateral lymph node, or extramural vessel invasion) were assigned into three groups, 1) Chemoradiotherapy (50 Gy of radiation combined with oral capecitabine) followed by consolidation chemotherapy using six cycles of XELOX(CNCT group), 2) Induction chemotherapy before chemoradiotherapy (INCT group), or 3) Chemoradiotherapy alone (Control group). Then enrolled patients were required to undergo radical surgery after neoadjuvant therapy. Patients in Control group need six cycles of XELOX after surgery. The primary end point was proportion of yp0-II, and watch-and-wait strategy after complete clinical response (cCR) was allowed. Results: Of the 257 patients enrolled, 255 patients were evaluable (Control: CNCT: INCT= 84: 86: 85). Neoadjuvant treatment related grade 3 or 4 toxicity was higher in TNT approach (7.1%, 23.3% and 32.9% in Control, CNCT and INCT, respectively), of with myelosuppression being most common. Compliance of chemoradiotherapy was lower in INCT group (98.8%, 100% and 90.6% in Control, CNCT and INCT, respectively). As to CNCT and INCT, 60.0% and 74.1% of patients completed six cycles of chemotherapy, with 76.7% and 83.5% completing four cycles of chemotherapy, respectively. Proportions of downstage (yp0-II + sustained cCR) were achieved 75.6% in CNCT group and 74.1% in INCT group, respectively, compared to 56.0% in Control group. CR rates (pCR + sustained cCR) were achieved 43.0% in CNCT group and 38.8% in INCT group, respectively, compared to 20.2% in Control group. Both TNT approaches did not increase the incidence of surgical complications (6.0%, 8.1% and 10.9% in Control, CNCT and INCT, respectively), with anastomotic fistula and abdominal infection being of most common. Conclusions: Both TNT approaches increased the probability of ≥ G3 acute toxicities, but most patients could tolerate 4 cycles of neoadjuvant chemotherapy. Both TNT approaches could achieve a higher proportion of downstage and CR rate. Clinical trial information: NCT04543695 .

Efficacy and Safety of High-Dose Vitamin C Combined with Total Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer (HCCSC R02 Study).

Forpatients with locally advanced rectal cancer (LARC), the standard treatment is fluoropyrimidine (FU) -based neoadjuvant chemoradiotherapy (NCRT) combined with curative surgery. The CAO/ARO/AIO-04 trial and FORWARC trial reported that the addition of oxaliplatin to FU -based NCRT contributed to improve pathologic complete response (pCR), nevertheless, increased the acute therapeutic toxicity. Some studies showed that vitamin C (VitC) had potential benefits on anti-tumor therapy and anti-inflammatory response. Therefore, we conducted this HCCSC R02 study to explore the efficacy and safety of adding a high-dose intravenous VitC to mFOLFOX6/XELOX -based NCRT in LARC. HCCSCR02 study was designed as a prospective, single-center phase II trial, which including pts aged 18-75 years with stage II/III rectal adenocarcinoma, distance from anus ≤12cm. The enrollment criteria included: staged with MRI as cT3/cT4 or cN1/2, or mesorectal fascia involvement (MRF+), or difficult to preserve the anus. Patients with glucose-6-phosphate dehydrogenase enzyme(G6PD) deficiency were excluded. Pelvic intensity modulated radiation therapy (IMRT) was given in 45-50.4Gy/25-28 fractions. Concurrently, two cycles of chemotherapy (mFOLFOX6 or XELOX) were administered during IMRT, as well as intravenous VitC (24g) delivered daily after the end of each radiation therapy. Additional 2-3 cycles of mFOLFOX6 / XELOX were adopted between the completion of radiotherapy and surgery. The primary endpoint was pCR rate. The secondary endpoints included radiation-related toxicities, overall survival (OS) and disease-free survival (DFS). This study is still recruiting. From May 15, 2021 to Feb 8, 2023, 19 pts were recruited and finished all the scheduled NCRT, of which the proportion of cT4, cT3, cN2, cN1 were 31.6%, 63.2%, 52.6%, 36.8%, respectively. In addition, 10 pts (52.6%) were diagnosed as MRF+ initially, and 8 pts (42.1%) had a lower primary tumor(≤5cm) who were considered difficult for anal preservation before NCRT. All subjects enrolled were confirmed to be proficient mismatch repair (pMMR). As a result, 18 pts underwent a total mesorectal excision (TME) all with R0-resection, and 8 pts were evaluated as pCR (44.4%, 8/18, confidence interval: 0.246-0.663), 11 as major pathological response rate (MPR) (61.6%, 11/18), respectively. The anus preservation rate in patients with lower diseases was 87.5% (7/8). One case accepted a watch-and-wait strategy because of clinical complete response (cCR). Overall, grade 3 toxicities were observed in 4 pts, including 3 leucopenia (15.8%, 3/19), 2 neutropenia (10.5%, 2/19) and 1 diarrhea (5.3%, 1/19). No grade 4 adverse event was observed. The addition of high-dose VitC to the mFOLFOX6/XELOX-based NCRT in LARC showed a promising pCR, well tolerance, particularly low rate of diarrhea, thus warrants further investigation. NCT04801511.

Total Neoadjuvant Therapy (TNT) with Full Dose Concurrent Chemotherapy in Locally Advanced Rectal Adenocarcinoma Including Signet Ring and Mucinous Cancers.

Total neoadjuvant therapy (TNT) with pre-operative chemotherapy and chemoradiotherapy results in improved survival and is becoming the new standard of care in locally advanced rectal cancer (LARC). We describe our experience with TNT consisting of induction chemotherapy followed by chemoradiotherapy using full dose 5FU without oxaliplatin. Adults with biopsy-proven, newly diagnosed LARC with high-risk characteristics on pelvic MRI (T4a or T4b, extramural vascular invasion, N2, mesorectal fascia involvement, enlargement/tumor deposits on lateral lymph nodes) were included. The TNT protocol comprised of six biweekly courses of modified FOLFOX6 followed by pelvic RT with four concurrent cycles of biweekly 5-FU 2600mg/m2 + LV 200mg/m2 without oxaliplatin to complete 20 uninterrupted weeks of full dose 5FU. Surgery was planned 11-13weeks after completing chemoradiotherapy. Eighty-four LARC patients, including 26% with signet-ring cell carcinoma, with high-risk MRI characteristics were treated with the TNT protocol with a 96% completion rate. Significant (> grade 3) toxicities included neutropenia (23.8%), diarrhea (14.2%) anemia (10.7%), and two deaths. The median DFS at 2years was 22.5months with better survival noted for those who underwent surgery or had cCR (with NOM) compared to those who did not undergo surgery (due to progression, inadequate regression, or patient preference despite residual disease) -mDFS 27.7months versus 11.4months, p = < 0.0001 and mOS 29.2months versus 15months p = < 0.0001. The hybrid TNT regimen was administered without significant dose delays or interruptions. Toxicity was manageable but with two treatment-related deaths. Ability to undergo surgery after TNT predicted for improved DFS and OS.

MRI with diffusion-weighted imaging in staging and restaging of cancer rectum

Abstract Background Magnetic Resonance Imaging (MRI) has emerged as one of the most reliable noninvasive methods for staging rectal carcinoma, due to its ability to precisely delineate rectal tumors. Aim The aim of this study is to assess role of diffusion-weighted (DW) imaging in primary staging and restaging of locally advanced rectal cancers. Patients and methods 40 cases with rectal cancer were included in the research referred to the Radio diagnosis department throughout the period from December 2018 to March 2022. Pelvic MRI with DW imaging was done for all cases. Results According to this studies adding DW imaging to conventional MRI among group I (patients with resectable rectal cancer) increased the diagnostic accuracy to 93.6%, sensitivity to 91%, and specificity to 100%. In group II (patients with locally advanced rectal carcinoma) there was significant increase in the diagnostic accuracy to 83.6%, giving also high negative predictive value as we were able to differentiate between complete responder and nonresponder. Furthermore, the diagnostic accuracy in the evaluation of the mesorectal fascia involvement was much improved after the addition of DW imaging. Conclusion DW imaging yields better diagnostic accuracy than using conventional MR imaging alone in initial staging and restaging of cases with locally advanced rectal cancer.

Can multidetector CT replace MRI for evaluating mesorectal fascia in rectal cancer?

Colorectal cancer is the fourth leading cause of cancer mortality. This study aims to compare the clinical outcomes of multidetector computed tomography (MDCT) with magnetic resonance imaging (MRI) for assessing mesorectal fascia (MRF) in patients with rectal cancer. This research was a cross-sectional study of 60 patients with rectal cancer referred to two centers in Isfahan, Al-Zahra, and Seyed-al-Shohada hospitals. Considered parameters included sex, tumoral location, nodal involvement, as well as tumoral description. To assess the invasion of MRF in rectal cancer, researchers used MRI, axial MDCT, and multiplanar reconstruction CT scan (MPRCT). Sensitivity, specificity, and techniques' positive and negative predictive values were measured. Also, to assess the statistical associations, the Kappa coefficient was used. There was no significant association between axial MDCT and MRI reports regarding MRF involvement (P>0.05). However, a statistical association was determined between the reports of multiplanar reconstruction CT (MPRCT) and MRI (P< 0.01, kappa=0.44). In addition, the association between MPRCT and MRI reports was statistically significant in patients with wall thickening and negative nodal involvement (Kappa = 0.699, P = 0.001). On the other hand, there was more agreement between MPRCT and MRI reports in patients with tumors in the middle or upper rectum. The association between MRI and MPRCT reports regarding MRF involvement was statistically significant in patients with wall thickening and negative nodal involvement in the upper and middle rectum. Consequently, it is possible to replace MRI with the MPRCT method for assessing MRF in some patients.

Radiotherapy, atezolizumab, and bevacizumab in rectal cancers with the aim of organ preservation: The TARZAN study.

158 Background: Rectal cancer is traditionally treated with total mesorectal excision (TME), with/without neoadjuvant radiotherapy (RT) and chemotherapy. This approach often leads to temporary or permanent colostomies and other long-term morbidity such as urinary and sexual dysfunction in over 60% of patients. Organ preservation is increasingly being pursued in patients with a clinical complete response (cCR) following neoadjuvant treatment, thereby aiming to avoid TME-surgery. Based on preclinical data suggesting immunomodulatory effects of RT, and the synergy of combined PD-L1/VEGF blockade in several tumor types, the TARZAN study (NCT04017455) combines these treatments aiming to increase chances of organ preservation in patients with mainly MMR proficient (pMMR) rectal cancer without the need for chemotherapy. Methods: Patients with clinical stage ≤T3ab N0-1 distal-mid rectal tumors without mesorectal fascia involvement underwent 5x5 Gy RT followed by 3 cycles of atezolizumab and bevacizumab. Response was evaluated by MRI and endoscopy. The primary endpoint was clinical complete and near-complete response (CR) rate at 12 weeks after RT. Secondary endpoints included safety, organ preservation, pathologic (near) CR in case of surgery, and relapse free survival. According to a Simon’s 2-stage design, ≥3 responders were needed in stage I (18 patients) to continue accrual into stage II. Here we report data from stage I. Results: Eighteen patients (14 male, median age 63), all with pMMR tumors, were treated. Six tumors were cN1 on MRI, 10/18 tumors were ≥4cm and for 10/18 patients abdominoperineal resection (APR) appeared necessary due to distal tumor location. At the time of response evaluation, (near-)CR was achieved in 10/18 (56%) patients according to the primary endpoint. With a median follow-up of 20 months, 9/18 (50%) patients remain without TME surgery. Of these 9 patients, 5 underwent local excision to achieve organ preservation and in 5 patients no additional intervention was needed (cCR). The remaining 9 patients underwent TME surgery (4 APR), and pathologic assessment revealed near-CR in two patients, and a pCR in one patient. Three patients developed distant recurrences, one in the organ-sparing group. Neoadjuvant treatment was well-tolerated with grade 3 study drug-related adverse events (AEs) in 1 (5%) patient. Grade 3 surgery-related AEs occurred in 5/9 (55%) patients, including 4 anastomotic leaks and 1 abscess. Conclusions: Neoadjuvant RT followed by atezolizumab and bevacizumab resulted in a promising rate of clinical (near-)CRs in 56% of patients without the need for chemotherapy, reaching the primary endpoint. Accrual is ongoing in stage II, in which an additional 20 patients will be treated. Clinical trial information: NCT04017455 .

Total neoadjuvant treatment for MRI-stratified high-risk rectal cancer: a single-center, single-arm, prospective Phase II trial (PKUCH-R02).

Induction chemotherapy combined with neoadjuvant chemoradiotherapy has been recommended for patients with high-risk, locally advanced rectal cancer. However, the benefit of more intensive total neoadjuvant treatment (TNT) is unknown. This study aimed to assess the safety and efficacy of induction chemotherapy combined with chemoradiotherapy and consolidation chemotherapy for magnetic resonance imaging-stratified high-risk rectal cancer. This was a single-center, single-arm, prospective Phase II trial in Peking University Cancer Hospital (Beijing, China). Patients received three cycles of induction oxaliplatin and capecitabine (CapeOX) followed by chemoradiotherapy and two cycles of consolidation CapeOX. The primary end point was adverse event rate and the second primary end points were 3-year disease-free survival rate, completion of TNT, and pathological downstaging rate. Between August 2017 and August 2018, 68 rectal cancer patients with at least one high risk factor (cT3c/3d/T4a/T4b, cN2, mesorectal fascia involvement, or extramural venous invasion involvement) were enrolled. The overall compliance of receiving the entire treatment was 88.2% (60/68). All 68 patients received induction chemotherapy, 65 received chemoradiotherapy, and 61 received consolidation chemotherapy. The Grade 3-4 adverse event rate was 30.8% (21/68). Nine patients achieved clinical complete response and then watch and wait. Five patients (7.4%) developed distant metastasis during TNT and received palliative chemotherapy. Fifty patients underwent surgical resection. The complete response rate was 27.9%. After a median follow-up of 49.2 months, the overall 3-year disease-free survival rate was 69.7%. For patients with high-risk rectal cancer, this TNT regimen can achieve favorable survival and complete response rates but with high toxicity. However, it is necessary to pay attention to the possibility of distant metastasis during the long treatment period.

Preliminary Results of a Prospective Phase II Study of Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer

<h3>Purpose/Objective(s)</h3> To analyze the safety and efficacy of total neoadjuvant therapy (TNT) followed by TME surgery for patients with locally advanced rectal cancer. <h3>Materials/Methods</h3> This study was designed as a prospective, multicenter, randomized phase II clinical study, which included patients aged 18-75 years with stage II / III rectal adenocarcinoma (including at least one of high-risk factors: mesorectal fascia involvement, T4, N2, positive lateral lymph node or extramural vessel invasion). According to the ratio of 1:1:1, eligible patients were randomly assigned into three groups: Chemoradiotherapy (CRT) → Surgery (S) → Adjuvant chemotherapy (Standard group), CRT → Neoadjuvant chemotherapy (NACT) → S (Consolidation chemotherapy group); or NACT → CRT → S (Induction chemotherapy group). CRT included pelvic radiotherapy with 50 Gy in 25 fractions and simultaneous oral capecitabine. NACT was adopted with XELOX scheme. The primary end point of this study was to explore the proportions of downstage, which included yp0-II or complete clinical response (cCR), for rectal cancer on two TNT strategies. <h3>Results</h3> From August 15, 2020 to February 15, 2022, a total of 224 patients were enrolled in this study (Standard group: Consolidation chemotherapy group: Induction chemotherapy group=69:78:75). Among them, 110 patients who completed preoperative treatment were included in safety analysis, and the median distance from the tumor to the anus was 5cm (range: 0-15cm), of which 81 cases (73.6%) and 29 (26.4%) were T3 and T4, 25 cases (22.7%) and 85 (77.3%) were N1 and N2, respectively; In addition, 83 patients (75.5%) were found to be mesorectal fascia involvement (MRF+). The probability of ≥ G3 acute toxicity in Standard group, Consolidation chemotherapy group and Induction chemotherapy group were 8.2% (5 / 61), 13.3% (4 / 30) and 31.6% (6 / 19), respectively, with myelosuppression being of most common. There was no toxicity-related death in all patients. In terms of tolerance, the completion rates of neoadjuvant therapy (Including treatment delay and dose reduction) in Standard group, Consolidation chemotherapy group and Induction chemotherapy group were 100% (61 / 61), 90% (27/ 30) and 100% (19 / 19), with the full dose completion rates of 100% (61/61), 73.3% (22/30) and 63.2% (12/19), respectively. 68 patients who completed the surgery or chose Wait / Watch strategy were included in efficacy analysis. The proportion of patients in the Standard group, Consolidation chemotherapy group and Induction chemotherapy group who reached stage 0-II after neoadjuvant treatment were 77.1% (27 / 35), 84.2% (16 / 19) and 57.1% (8 / 14), respectively, with CR rates (pCR + sustained cCR) of 22.9% (8 / 35), 42.1% (8 / 19) and 28.6% (4 / 14), respectively. <h3>Conclusion</h3> The acute toxicities of two TNT groups were acceptable and well tolerated. And the tumor downstage rate of Consolidation chemotherapy group was encouraging. <i>ClinicalTrials.gov</i> No.: NCT04543695

Extramural vascular invasion as an independent prognostic marker in locally advanced rectal cancer: propensity score match pair analysis.

In rectal cancers, presence of extramural vascular invasion on MRI (mrEMVI) is associated with poor survival. The independent influence of mrEMVI in the presence of other prognostic factors has not been previously analyzed using match pair analysis. Consecutive 92 patients having mrEMVI at presentation treated between January 2016 and December 2018 were matched with 92 patients (1:1) without mrEMVI. Matching parameters were T stage, mesorectal fascia involvement, and tumor differentiation. The presence and absence of mrEMVI were correlated to outcomes. An event was defined as locoregional failure or distant metastasis or poor response to chemoradiation rendering the rectal tumor as inoperable. At 3years, in the mrEMVI-positive cohort, 59% had an event and in the mrEMVI-negative cohort, 45% had an event (p = 0.026). Local control was 90.2% (12recurrences in 122 who underwent surgery), two recurrences in the mrEMVI-positive cohort and ten patients in the mrEMVI-negative cohort, which missed statistical significance (p = 0.06). Distant metastasis-free survival was significantly worse in the mrEMVI-positive cohort versus the mrEMVI-negative cohort (58.2% vs. 69.4%) (p = 0.022). Similarly, Overall survival was significantly inferior in mrEMVI-positive cohort compared to the mrEMVI-negative cohort (57% vs. 72.4%) (p = 0.02). The multivariate regression analysis confirmed the independent predictive value of mrEMVI. CONCLUSION: Extramural vascular invasion detected through MRI is an independent risk factor for distant metastasis in the locally advanced carcinoma rectum. Aggressive treatment regimens like total neoadjuvant treatment should be considered in these cases pending randomized control studies.

Role of PET/CT in the follow-up of postoperative and/or post-therapy cancer rectum: comparison with pelvic MRI

BackgroundIn locally advanced rectal cancer, many imaging modalities are used, for example 18F-2-fluoro-2-deoxy-d-glucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) and MRI. The aim of our study is to compare the diagnostic accuracy of 18 F-FDG-PET/CT & pelvic MRI; as well as to investigate the possible added value of using combined pelvic MRI and PET-CT for assessment of tumor response.ResultsRegarding the presence of local tumor, both PET CT and MRI showed perfect agreement with 97.1% overall accuracy, while in N category, PET CT showed higher specificity but lower sensitivity than MRI. MRI was superior to PET/CT in detecting extension to nearby organs; owing to the more anatomical details of MRI regarding the involvement of mesorectal fascia and EMVI. Almost total agreement of both MRI and PET/CT was noticed in evaluating post-therapy and postoperative complications.ConclusionFor locally advanced rectal cancer (pT3–4 N0 M0 or any T N1 M0), a multimodality strategy has been shown to be the best option to evaluate local disease process, using the diagnostic criteria that were based on morphology, as well as glucose uptake, instead of the SUV alone for reassessment of post-therapy or postoperative changes.

Diagnostic accuracy of MRI in mesorectal fascial involvement

Introduction: Evaluation of mesorectal fascial involvement in rectal cancer is of prime importance in decision making regarding treatment options.&#x0D; Objective: To determine diagnostic accuracy of Magnetic Resonance Imaging (MRI) in detection of mesorectal fascia involvement in rectal carcinoma patients using histopathology as gold standard.&#x0D; Materials &amp; Methods: A comparative study was performed in the Radiology department of Kuwait Teaching Hospital, Peshawar, from January 1, 2021, till December 31, 2021, on 155 patients of rectal carcinoma who had their MRI done for rectal cancer on 0.3T MR Machine. Surgical findings like mesorectal fascial involvement by the tumor, presence/absence of pelvic lymph nodes within 5mm of mesorectal fascia, and staging of the tumor were included as variables. Specimens were sent in formalin to a histopathologist, and findings were considered for comparison. Data were analyzed using SPSS version 23.&#x0D; Results: Out of 155 patients, 82 patients showed mesorectal fascial involvement whereas 73 patients were Circumferential Resection Margin (CRM) negative. Out of these 7 patients were falsely labeled as CRM positive on MRI, whereas 9 patients were falsely labeled as CRM negative on MRI. Positive predictive value was 91%, with negative predictive value of 88%. Diagnostic accuracy was 89.6%. Sensitivity was 89% whereas specificity was 90.4%.&#x0D; Conclusion: MRI has high sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for detection of mesorectal fascial involvement in case of rectal carcinoma taking 5mm as cut off value.

Diagnostic Accuracy of Multidetector Computed Tomography in Detecting Mesorectal Fascia Involvement in Colorectal Carcinoma

Objectives: To determine the diagnostic accuracy of multi detector computed tomography (MDCT) in detecting mesorectal fascia involvement in colorectal carcinoma, taking histopathology as a gold standard.&#x0D; Study Design: Cross-sectional study.&#x0D; Place and Duration of Study: Department of Radiology, Combined Military Hospital Quetta from Jun to Dec 2019.&#x0D; Methodology: A total of 117 suspected patients of colorectal carcinoma, aged 40-80 years of either gender were included. All the patients underwent MDCT and then were looked for mesorectal fascia involvement. After surgical intervention, the his to pathological result of respected specimens was correlated with MDCT findings.&#x0D; Results: MDCT showed mesorectal fascia involvement in 66 (56.41%) patients. Histopathology confirmed mesorectal fascia involvement in 62 (52.99%) cases, whereas 55 (47.01%) patients revealed no mesorectal fascia involvement. In MDCT positive patients, 56 patients were true positive, while ten patients were false positive. Among 51 MDCT negative patients, 6 were false-negative while 45 were true negative. Overall results of sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of MDCT in detecting mesorectal fascia involvement, taking histopathology as the gold standard was, 90.32%, 81.82%, 84.85%, 88.24% and 86.32% respectively.&#x0D; Conclusion: This study concluded that MDCT is a recommended modality due to its high sensitivity. It is an accurate modality for pre-operative detecting mesorectal fascia involvement in colorectal carcinoma patients.

Development and external validation of prognostic nomograms for liver disease-free and overall survival in locally advanced rectal cancer with neoadjuvant therapy: a post cohort study based on the FOWARC trial.

BackgroundThere is still a lack of nomograms that can accurately predict liver metastasis and poor prognosis after neoadjuvant therapy for locally advanced rectal cancer (LARC). Effective nomograms may help clinicians better identify LARC patients with potential high-risk risks, so as to carry out more targeted monitoring, treatment and follow-up.MethodsThe nomograms were based on the FOWARC trial (NCT01211210), which included 302 LARC patients who underwent neoadjuvant treatment before surgery at the Sixth Affiliated Hospital of Sun Yat-sen University from 2011 to 2014. The predictive accuracy and discriminative ability of the nomograms were determined by the concordance index (C-index) and calibration curve. The results were validated using bootstrap resampling and a prospective study on 100 patients in 2017.ResultsThe 3-year liver disease-free survival (LDFS) rate after neoadjuvant treatment for LARC was 91.65% (training cohort 92.22%, validation cohort 90.01%). Factors associated with LDFS were hepatitis B virus (HBV) infection, anemia, lymph node number, postoperative T stage and tumor nodule, which were all included in the nomogram for LDFS. The C-indies of the nomogram for LDFS were 0.828 and 0.845 in the training and validation cohorts. The 3-year overall survival (OS) rate was 94.14% (training cohort 94.13%, validation cohort 94.05%). Factors in the nomogram for OS were mesorectal fascia involvement (MRF), postoperative N stage, pathological differentiation, tumor nodule and neural invasion. The C-indies of the nomogram for predicting OS were 0.73 and 0.774 in the training and validation cohorts. The calibration curve for the survival probability showed good agreement between the nomogram predictions and the actual observations.ConclusionsThe nomograms established in this study can effectively predict LDFS and has good clinical application potential for OS in LARC patients treated with neoadjuvant therapy.

Feasibility of the semi-opened method of specimen resection for a circumferential resection margin in rectal cancer surgery: a multicenter study.

A circumferential resection margin (CRM) > 1mm is a surrogate marker of oncologic outcomes in rectal cancer patients. In Japan, because the mesentery is removed from the rectum, the CRM cannot be measured. This multicenter prospective study evaluates the feasibility of a resected specimen processing method that allows CRM measurement. Fifty patients with rectal cancer were enrolled. Resected specimens were processed as previously reported. The primary outcomes were CRM measurement and the rate of CRM positivity. The secondary outcomes were the quality of total mesorectal excision, the possibility to visualize and sample the tumor, the number of harvested lymph nodes, and comparison between the pathological CRM and preoperative mesorectal fascia (MRF) involvement. This study was registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry under identification number UMIN000031735. The CRM was measurable in all patients and found to be positive in three (6%). We confirmed tumor localization, sampled the tumor, and measured the distal margin in all patients. A median of 20 lymph nodes were harvested. The concordance rate between preoperative MRF involvement and pathological CRM status was 90%. A semi-opened rectal specimen with transverse slicing is a feasible method for measuring the CRM.

Current controversies in TNM for the radiological staging of rectal cancer and how to deal with them: results of a global online survey and multidisciplinary expert consensus

ObjectivesTo identify the main problem areas in the applicability of the current TNM staging system (8th ed.) for the radiological staging and reporting of rectal cancer and provide practice recommendations on how to handle them.MethodsA global case-based online survey was conducted including 41 image-based rectal cancer cases focusing on various items included in the TNM system. Cases reaching < 80% agreement among survey respondents were identified as problem areas and discussed among an international expert panel, including 5 radiologists, 6 colorectal surgeons, 4 radiation oncologists, and 3 pathologists.ResultsThree hundred twenty-one respondents (from 32 countries) completed the survey. Sixteen problem areas were identified, related to cT staging in low-rectal cancers, definitions for cT4b and cM1a disease, definitions for mesorectal fascia (MRF) involvement, evaluation of lymph nodes versus tumor deposits, and staging of lateral lymph nodes. The expert panel recommended strategies on how to handle these, including advice on cT-stage categorization in case of involvement of different layers of the anal canal, specifications on which structures to include in the definition of cT4b disease, how to define MRF involvement by the primary tumor and other tumor-bearing structures, how to differentiate and report lymph nodes and tumor deposits on MRI, and how to anatomically localize and stage lateral lymph nodes.ConclusionsThe recommendations derived from this global survey and expert panel discussion may serve as a practice guide and support tool for radiologists (and other clinicians) involved in the staging of rectal cancer and may contribute to improved consistency in radiological staging and reporting.Key Points• Via a case-based online survey (incl. 321 respondents from 32 countries), we identified 16 problem areas related to the applicability of the TNM staging system for the radiological staging and reporting of rectal cancer.• A multidisciplinary panel of experts recommended strategies on how to handle these problem areas, including advice on cT-stage categorization in case of involvement of different layers of the anal canal, specifications on which structures to include in the definition of cT4b disease, how to define mesorectal fascia involvement by the primary tumor and other tumor-bearing structures, how to differentiate and report lymph nodes and tumor deposits on MRI, and how to anatomically localize and stage lateral lymph nodes.• These recommendations may serve as a practice guide and support tool for radiologists (and other clinicians) involved in the staging of rectal cancer and may contribute to improved consistency in radiological staging and reporting.

Short-term outcomes of preoperative chemotherapy in patients with upper ampullary rectal cancer

The purpose of the study: to analyze short-term efficacy and tolerability of preoperative chemotherapy in patients with upper ampullary rectal carcinoma. Material and methods. A prospective study conducted at the cancer research institute (tomsk, russia) between 2018 and 2020 included 47 patients with operable cancer of the upper ampullary part of the rectum with mrt3n0m0 (mesorectal fascia involvement (crm+) or low-grade cancer), mrt4аn0m0 and mrt3–4аn1m0. All patients were divided into two groups. Group i comprised 22 patients, who received 3 cycles of chemotherapy with folfox-4 followed by surgery. Group ii consisted of 25 patients, who underwent surgery alone. All patients underwent arterior resection of the rectum. Results. Group i patients completed all three cycles of preoperative chemotherapy. Downstaging after chemotherapy was observed in 16 (72.7 %) patients. No severe side effects of chemotherapy were found. The frequency of radical surgeries (r0) was 100 %. No significant differences in the rate of postoperative complications between the treatment groups were observed (18.2 % and 16 %, respectively, p&gt;0.05). There were no cases of postoperative mortality. Conclusion. Compared with surgery alone, preoperative chemotherapy followed by surgery demonstrates a high short-term efficacy, does not adversely affect the course of the perioperative period.

Short-course radiotherapy and chemotherapy for conversion surgery in patients with unresectable metastatic rectal cancer: a preliminary case series study.

Curative treatment is challenging in patients with locally advanced rectal cancer and unresectable metastases. The aim of this study was to evaluate the clinical outcomes of short-course radiotherapy (RT) followed by systemic chemotherapy for patients with rectal cancer with mesorectal fascia (MRF) involvement and unresectable distant metastases. The study included consecutive patients diagnosed as having metastatic mid-to-low rectal cancer treated with short-course RT followed by systemic chemotherapy for conversion radical or palliative surgery between 2014 and 2019 at Gil Medical Center. The patients had primary rectal tumors involving the MRF and unresectable distant metastases. The treatment strategies were determined in a multidisciplinary team discussion. Seven patients (five men and two women) underwent short-course RT (5×5 Gy) and preoperative systemic chemotherapy. The median age was 68 years (range, 46-84 years), and the median distance from the anal verge to the primary tumor was 6.0 cm (range, 2.0-9.0 cm). During the median follow-up period of 29.4 months, three patients underwent conversion radical surgery with R0 resection, two underwent palliative surgery, and two could not undergo surgery. No postoperative major morbidity or mortality occurred. The patients who underwent conversion complete radical surgery showed good long-term survival outcomes, with an overall survival time of 29.4-48.8 months and progression-free survival time of 14.7-41.1 months. Short-course RT followed by systemic chemotherapy could provide patients with unresectable stage IV rectal cancer a chance to undergo to conversion radical surgery with good long-term survival outcomes.

Value of Primary Rectal Tumor PET/MRI in the Prediction of Synchronic Metastatic Disease.

To analyze the associations between positron emission tomography (PET)/magnetic resonance imaging (MRI) features for primary rectal tumors and metastases. Between November 2016 and April 2018, 101 patients with rectal adenocarcinoma were included in this prospective study (NCT02537340) for whole-body PET/MRI for baseline staging. Two readers analyzed the PET/MRI; they assessed the semiquantitative PET features of the primary tumor and the N- and M-stages. Another reader analyzed the MRI features for locoregional staging. The reference standard for confirming metastatic disease was biopsy or imaging follow-up. Non-parametric tests were used to compare the PET/MRI features of the participants with or without metastatic disease. Binary logistic regression was used to evaluate the associations between the primary tumor PET/MRI features and metastatic disease. A total of 101 consecutive participants (median age 62years; range: 33-87years) were included. Metastases were detected in 35.6% (36 of 101) of the participants. Among the PET/MRI features, higher tumor lesion glycolysis (352.95 vs 242.70; P = .46) and metabolic tumor volume (36.15 vs 26.20; P = .03) were more frequent in patients with than in those without metastases. Additionally, patients with metastases had a higher incidence of PET-positive (64% vs 32%; P = .009) and MRI-positive (56% vs 32%; P = .03) mesorectal lymph nodes, extramural vascular invasion (86% vs 49%; P > .001), and involvement of mesorectal fascia (64% vs 42%; P = .04); there were also differences between the mrT stages of these two groups (P = .008). No differences in the maximum standardized uptake values for the primary tumors in patients with and without metastases were observed (18.9 vs 19.1; P = .56). Multivariable logistic regression showed that extramural vascular invasion on MRI was the only significant predictor (adjusted odds ratio, 3.8 [95% CI: 1.1, 13.9]; P = .001). PET/MRI facilitated the identification of participants with a high risk of metastatic disease, though these findings were based mainly on MRI features.