Presence Of Extramural Venous Invasion Research Articles

The diagnostic accuracy of local staging in colon cancer based on computed tomography (CT): evaluating the role of extramural venous invasion and tumour deposits.

The shift from adjuvant to neoadjuvant treatment in colon cancer demands the radiological selection of patients for systemic therapy. The aim of this study was to evaluate the accuracy of the CT-based TNM stage and high-risk features, including extramural venous invasion (EMVI) and tumour deposits, in the identification of patients with histopathological advanced disease, currently considered for neoadjuvant treatment (T3-4 disease). All consecutive patients surgically treated for non-metastatic colon cancer between January 2018 and January 2020 in a referral centre for colorectal cancer were identified retrospectively. All tumours were staged on CT according to the TNM classification system. Additionally, the presence of EMVI and tumour deposits on CT was evaluated. The histopathological TNM classification was used as reference standard. A total of 176 patients were included. Histopathological T3-4 colon cancer was present in 85.0% of the patients with CT-detected T3-4 disease. Histopathological T3-4 colon cancer was present in 96.4% of the patients with CT-detected T3-4 colon cancer in the presence of both CT-detected EMVI and CT-detected tumour deposits. Histopathological T0-2 colon cancer was present in 50.8% of the patients with CT-detected T0-2 disease, and in 32.4% of the patients without CT-detected EMVI and tumour deposits. The diagnostic accuracy of CT-based staging was comparable with previous studies. The presence of high-risk features on CT increased the probability of histopathological T3-4 colon cancer. However, a substantial part of the patients without CT-detected EMVI and tumour deposits was diagnosed with histopathological T3-4 disease. Hence, more accurate selection criteria are required to correctly identify patients with locally advanced disease.

Survey of rectal cancer MRI technique and reporting tumour descriptors in the UK: a multi-centre British Society of Gastrointestinal and Abdominal Radiology (BSGAR) audit

To evaluate variation in magnetic resonance imaging (MRI) technique and reporting of rectal cancer staging examinations across the UK. A retrospective, multi-centre audit was undertaken of imaging protocols and information documented within consecutive MRI rectal cancer reports between March 2020 and August 2021, which were compared against American and European guidelines. Inclusion criteria included histologically proven rectal adenocarcinoma and baseline staging MRI rectum only. Fully anonymised data from 924 MRI reports by 78 radiologists at 24 centres were evaluated. Thirty-two per cent of radiologists used template reporting, but these reports offered superior documentation of 13 out of 18 key tumour features compared to free-text reports including T-stage, relation to peritoneal reflection and mesorectal fascia (MRF), nodal status, and presence of extramural venous invasion (EMVI; p<0.027 in each). There was no significant differences in the remaining five features. Across all tumour locations, the tumour relationship to the MRF, the presence of EMVI, and the presence of tumour deposits were reported in 79.5%, 85.6%, and 44% of cases, respectively, and tumour, nodal, and distant metastatic stage documented in 94.4%, 97.7%, and 78.3%. In low rectal tumours, the relationship to the anal sphincter complex was reported in only 54.6%. Considerable variation exists in rectal cancer MRI acquisition and reporting in this sample of UK centres. Inclusion of key radiological features in reports must be improved for risk stratification and treatment decisions. Template reporting is superior to free-text reporting. Routine adoption of standardised radiology practices should now be considered to improve standards to facilitate personalised precision treatment for patients to improve outcomes.

Extramural Venous Invasion and Tumor Deposit at Diffusion-weighted MRI in Patients after Neoadjuvant Treatment for Rectal Cancer.

Background Diffusion-weighted (DW) imaging is useful in detecting tumor in the primary tumor bed in locally advanced rectal cancer (LARC) after neoadjuvant therapy, but its value in detecting extramural venous invasion (EMVI) and tumor deposit is not well validated. Purpose To evaluate diagnostic accuracy and association with patient prognosis of viable EMVI and tumor deposit on DW images in patients with LARC after neoadjuvant therapy using whole-mount pathology specimens. Materials and Methods This retrospective study included patients who underwent neoadjuvant therapy and surgery from 2018 to 2021. Innovative five-point Likert scale was used by two radiologists to independently evaluate the likelihood of viable EMVI and tumor deposit on restaging DW MRI scans in four axial quadrants (12 to 3 o'clock, 3 to 6 o'clock, 6 to 9 o'clock, and 9 to 12 o'clock). Diagnostic accuracy was assessed at both the per-quadrant and per-patient level, with whole-mount pathology as the reference standard. Weighted κ values for interreader agreement and Cox regression models for disease-free survival and overall survival analyses were used. Results A total of 117 patients (mean age, 56 years ± 12 [SD]; 70 male, 47 female) were included. Pathologically proven viable EMVI and tumor deposit was detected in 29 of 117 patients (25%) and in 44 of 468 quadrants (9.4%). Per-quadrant analyses showed an area under the receiver operating characteristics curve of 0.75 (95% CI: 0.68, 0.83), with sensitivity and specificity of 55% and 96%, respectively. Good interreader agreement was observed between the radiologists (κ = 0.62). Per-patient analysis showed sensitivity and specificity of 62% and 93%, respectively. The presence of EMVI and tumor deposit on restaging DW MRI scans was associated with worse disease-free survival (hazard ratio [HR], 5.6; 95% CI: 2.4, 13.3) and overall survival (HR, 8.9; 95% CI: 1.6, 48.5). Conclusion DW imaging using the five-point Likert scale showed high specificity and moderate sensitivity in the detection of viable extramural venous invasion and tumor deposits in LARC after neoadjuvant therapy, and its presence on restaging DW MRI scans is associated with worse prognosis. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Méndez and Ayuso in this issue.

Operative and Pathological Factors in Right-Sided Colon Cancers: How Can We Improve the Outcomes?

Though the tumour-node-metastasis staging classification is the standard approach to risk stratification in patients with colorectal cancer, several other important variables including the presence of extramural venous invasion (EMVI), the tumour mismatch repair status, as well as surgical technique and its influence on lymph node yieldall have an impact on long-term survival. This study aims to review both the impact of the type of operation on lymph node yield: complete mesocolic excision (CME) versus right hemicolectomy, and the impact of EMVI and microsatellite instability in predicting overall survival in patients undergoing a right hemicolectomy for colon cancer. Data of all patients who underwent an elective or emergency right hemicolectomy with curative intent for colon cancer between January 2013 and June 2022 (inclusive) was collected for this single-centre retrospective study. Kaplan-Meier survival curves were calculated using the Statistical Package for the Social Sciences (SPSS version 28, IBM Corp., Armonk, NY) software, and the log-rank (Mantel-Cox) test was used to compare survival distribution between different groups. A total of 421 patients underwent a right hemicolectomy for colon cancer with curative intent during the study period. EMVI was present in 173 (41%) tumours. Survival analysis showed significantly reduced cancer-related survival in patients with EMVI-positive tumours (p < 0.001), with five-year survival rates of 70% in EMVI-positive groups versus 96% in EMVI-negative groups. Subgroup analysis showed a significant difference in survival between node-positive and node-negative tumours in cancers found to have EMVI (p < 0.001). Mean lymph node yield was significantly higher in the CME group versus the standard right hemicolectomy group (p < 0.001). We found no significant difference in survival between patients with microsatellite instability-high (MSI-H) tumours and microsatellite stable (MSS) tumours (p = 0.432). Consideration of tumour biology and adopting the optimum surgical technique are factors that may influence long-term survival in patients with colorectal cancer. Extramural venous invasion is an important prognostic indicator of adverse outcomes in patients with right-sided colon cancer. Our study demonstrates a reduction in survival in patients with EMVI-positive tumours when undertaking subgroup analysis by the presence or absence of nodal disease. Further research needs to be undertaken to compare the relative efficacy of neoadjuvant versus adjuvant chemotherapy in right-sided cancers known to be EMVI-positiveas some patients will fail to have adjuvant chemotherapy due to postoperative complications, thereby delaying recovery and missing the optimum window for treatment.

433P Pre-treatment and post-treatment MRI extramural venous invasion, predicts disease-free survival and overall survival, in locally advanced rectal cancer

Presence of extramural venous invasion (EMVI) by magnetic resonance imaging (MRI) is an independent poor prognostic factor in locally advanced rectal cancer (LARC). Nevertheless, the efficacy of both pre-neoadjuvant therapy (NAT) and post-NAT MRI EMVI assessment to predict pathological response and long-term benefit (in terms of disease-free survival (DFS) and overall survival (OS) has not been clearly established. We analyzed 239 patients with LARC receiving NAT with continuous infusion fluorouracil (n=229) or capecitabine (n=10) diagnosed between 2009 and 2019. Baseline and post-NAT MRI EMVI status was assessed in 214 and 173 patients respectively by two radiologists with more than 20-year and 5-year experience. When discrepancies, EMVI status was decided by consensus. Post-surgical pathologic assessment detached good-responders (ypT0N0 and ypT1-2N0) from poor-responders (ypT3Nx or ypTxN1/2). Three-year DFS and 5-year OS were estimated using Kaplan-Meier product-limit method. Baseline EMVI positive (91/214; 42%) was significantly associated with poor pathological response (74/91; 81%) vs. EMVI negative (52/123; 43%), p=0.0001. In the subset of patients evaluated with pre and post MRI, 69/173 (40%) presented positive EMVI at baseline. 21/69 (30%) patients with positive baseline EMVI became negative after therapy (EMVI (+/-)). Three-year DFS was 80.9% in EMVI (-/-), 66.7% in EMVI (+/-), and 45.2% in EMVI (+/+), HR 1.84 (95% CI 1.38-2.44), p=0.000026. Five-year OS was 82.6%, 73.9% and 57.3%, respectively, with HR 1.67 (95% CI 1.26-2.23), p=0.0004. Baseline EMVI accurately predicted pathological efficacy after conventional NAT. Patients that negativized EMVI (+/-) showed significantly better DFS and OS compared to patients that remained positive EMVI (+/+).

Extramural venous invasion (EMVI) in colorectal cancer is associated with increased cancer recurrence and cancer-related death

IntroductionColorectal cancer (CRC) outcomes vary depending on tumour biology, with several features used to predict disease behaviour. Extramural venous invasion (EMVI) is associated with negative outcomes and its presence has been established as an indicator of more aggressive disease in CRC. MethodsA prospectively maintained database was examined for patients undergoing curative resection for non-metastatic CRC between 2012 and 2018 in a tertiary institution. Clinicopathological factors were compared to assess their impact on recurrence, all-cause mortality and cancer-related death. Kaplan Meier analysis of the association between EMVI and these endpoints was performed, and univariable and multivariable analysis was carried out to establish the relationship of predictive factors in oncological outcomes. ResultsEighty-eight (13.5%) of 654 patients developed recurrence. The mean time to recurrence was 19.8 ± 13.5 months. There were 36 (5.5%) cancer-related deaths at a mean duration of follow-up of 46.3 ± 21.6 months. Two hundred and sixty-six patients had extramural venous invasion (40.7%). EMVI was significantly associated with reduced overall recurrence-free survival, systemic recurrence-free survival, and increased cancer-related death on univariate analysis (p < 0.001 for all, Fig. 1), and multivariable analysis (OR 1.8 and 2.1 respectively, p < 0.05 for both). ConclusionEMVI is associated with a poor prognosis, independent of stage, nodal status and other histopathological features. The presence of EMVI should be strongly considered as an indication for adjuvant therapy.

MRI Staging in an Evolving Management Paradigm for Rectal Cancer, From the AJR Special Series on Cancer Staging.

The treatment of rectal cancer centers around the distinct but related goals of management of distant metastases and management of local disease. Optimal local management requires attention to the primary tumor and its anatomic relationship to surrounding pelvic structures, with the goal of minimizing local recurrence (LR). High-resolution MRI is ideally suited for this purpose; application of MRI-based criteria in conjunction with optimized surgical and pathologic techniques has successfully reduced LR rates. This success has led to a shift away from using the TNM-based National Comprehensive Cancer Network (NCCN) guidelines as the sole determinant of whether a patient receives neoadjuvant chemoradiation. The new model uses a hybrid approach for assigning risk categories that combines elements of the TNM staging system with MRI-based anatomic features. These risk categories incorporate tumor proximity to the circumferential resection margin, T category, distance to the anal verge, and presence of extramural venous invasion to classify rectal tumors as low, intermediate, or high risk. This approach has been validated by accumulated data from numerous multiinstitutional studies. This article illustrates key anatomic concepts, depicts common interpretive errors and pitfalls, and discusses ongoing limitations; these insights should guide radiologists in optimal rectal MRI interpretation.

Prognostic Significance of EMVI in Rectal Cancer in a Tertiary Cancer Hospital in India.

Background Presence of extramural venous invasion (EMVI) is a poor prognostic factor for rectal cancer as per literature. However, India-specific data are lacking. Aim The aim of the study is to determine the prognostic significance of EMVI in locally advanced rectal cancer on baseline MRI. Materials and Methods We retrospectively reviewed 117 MRIs of operable non-metastatic locally advanced rectal cancers in a tertiary cancer institute. Three dedicated oncoradiologists determined presence or absence of EMVI, and its length and thickness, in consensus. These patients were treated as per standard institutional protocols and followed up for a median period of 37 months (range: 2–71 months). Kaplan-Meier curves (95% CI) were used to determine disease-free survival (DFS), distant-metastases free survival (DMFS), and overall survival (OS). Univariate analysis was performed by comparing groups with log-rank test. Results EMVI positive cases were 34/114 (29%). More EMVI-positive cases developed distant metastasis compared with EMVI-negative cases (14/34–41% vs. 22/83–26%). The difference, however, was not statistically significant ( p = 0.146). After excluding signet-ring cell cancers ( n = 14), EMVI showed significant correlation with DMFS ( p = 0.046), but not with DFS or OS. The median thickness and length of EMVI was 6 and 14 mm, respectively in patients who developed distant metastasis, as compared with 5 and 11 mm in those who did not, although this difference was not statistically significant. Conclusion EMVI is a predictor of distant metastasis in locally advanced non-metastatic, non-signet ring cell rectal cancers. EMVI can be considered another high-risk feature to predict distant metastasis.

Circulating tumor DNA and circumferential resection margin as key prognostic indicators for survival in rectal cancer.

3579 Background: Recurrence of colorectal cancer has been linked to the presence of epigenetic circulating tumour DNA (ctDNA) in patient plasma after surgery. The prognostic significance of ctDNA prior to treatment remains unknown. This study investigated the correlation between pre-treatment ctDNA and current radiological (MRI) prognostic markers in patients with rectal cancer. Methods: Forty-two patients with rectal cancer were enrolled, with all having staging MRI prior to treatment. Plasma was taken for ctDNA at diagnosis. The presence of either methylated branched-chain amino acid transaminase 1 (BCAT1) or Ikaros family zinc finger (IKZF1) in cell-free DNA from plasma was deemed a positive ctDNA result. Correlation of MRI prognostic indicators and ctDNA results was assessed with chi-square tests. Univariable and multivariable cox regression analyses were performed to determine variables associated with overall survival (OS). Results: Mean age was 64.4 years (SD 12.5) and majority were male (30/42, 71.4%). 11, 13, 9 &amp; 9 patients had stages I, II, III, IV respectively. Patients had a minimum follow-up of 36 months. Thirty-three (78.6%) patients received neoadjuvant chemoradiotherapy. 29 (69.0%) patients underwent surgical resection. 3-year survival rate was 64% in the overall group. 67% (n=28/42) of patients were positive for the methylated ctDNA at diagnosis. 11 out of 12 patients with a positive circumferential resection margin (CRM +) were ctDNA positive (p=0.03). Univariable analysis showed that prognostic indicators for OS were presence of extramural venous invasion (EMVI) (HR 3.0, 95% CI 1.1-8.4), CRM+ (HR 12.2, 95%CI 3.9-37.6), metastatic disease (HR 7.32, 95% CI 2.63-20.37) and ctDNA% methylation (HR 1.1, 95% CI 1.04-1.13) (Table 1). The presence of CRM+ and a positive ctDNA had a HR of 20.5 (95% CI 5.1-82.3). With multivariable analysis, including adjustment for age and EMVI, only CRM+/ctDNA+ variable was an independent predictor for poor survival (HR 20.2, 95% CI 4.5-90.9). Conclusions: In rectal cancer, almost all patients with CRM involvement have ctDNA, and these patients had the worst prognosis. Future studies with longitudinal ctDNA assessment pre and post treatment could potentially inform prognosis and help tailor patients’ treatment.[Table: see text]

Multifocal extramural venous invasion detected with an elastin stain as a predictor of cancer-specific outcomes in stage I-III resected colorectal cancer (CRC).

114 Background: ExtraMural Venous Invasion (EMVI) is considered an indicator of poor prognosis in patients who have undergone resection of primary CRC, but its use has not been widely adopted in staging systems or nomograms. Staining for elastin may facilitate the accurate detection of EMVI and minimize interobserver variability, as well as enable the assessment of specific features of EMVI including focality and size. We examined the prognostic potential of EMVI detected by elastin staining at a tertiary center that performs a high volume of CRC resections. Methods: This is a single-institution, observational study of consecutive patients who underwent resection of primary CRC between 01/2011 and 12/2016 (n=556). All pathology specimens were re-assessed by expert reviewers who were blinded to patient outcomes. Venous invasion was detected using an elastin trichrome stain and classified as IntraMural or ExtraMural. The number of VI foci, as well as the maximum foci width and length, were also determined. Disease-specific and recurrence-free survival (DSS, RFS) were estimated using the Kaplan-Meier method and group differences were assessed using the log-rank test. Cox proportional-hazard models were used to calculate hazard ratios (HR) and 95% CI. For the present analysis, patients with stage IV (n=86) CRC were excluded. Results: The cohort for analysis included 470 patients (264M, 206F; TNM 8th edition Stage I/II n=291; Stage III n=179) with a median follow-up time of 63 months (0.1-114). EMVI was detected in 33% of all cases (20% in Stage I/II vs. 55% in Stage III; p&lt;0.0001). For the entire cohort, DSS and RFS at 5 years were 86% and 76%, respectively. The presence of EMVI was associated with significantly worse DSS and RFS at 5-years (73% and 54%) compared to patients with no VI (92% and 85%) or IMVI alone (93% and 89%; p&lt;0.0001). The majority of EMVI was multifocal (69%) vs. unifocal (31%). Interestingly, multifocal EMVI was prognostic for worse 5-year DSS (65%), whereas unifocal EMVI was similar to the absence of EMVI (91% and 92%, respectively; p&lt;0.0001). A Cox-proportional hazards model showed worsening DSS with increasing number of detected EMVI foci (1 focus: HR 1.1, 2-4 foci: HR 3.3, &gt;4 foci: HR 7.9; p&lt;0.0001). A similar trend was observed for RFS. Neither the maximum width or length of EMVI foci were prognostic of DSS or RFS. Conclusions: To our knowledge, the prognostic role of EMVI focality in CRC has not been previously explored. In this cohort of Stage I - III CRC patients, multifocal EMVI as assessed by elastin staining was a powerful predictor of cancer-specific death and recurrence-free survival. Elastin staining, which improves the accuracy and objectivity of EMVI detection, may allow validation of EMVI as an independent prognostic variable that should be incorporated into staging systems and nomograms.

MRI of Extramural Venous Invasion in Locally Advanced Rectal Cancer: Relationship to Tumor Recurrence and Overall Survival.

Purpose To study the relationship between MRI-defined extramural venous invasion (EMVI) prior to treatment and prognosis in patients with locally advanced rectal cancer treated with neoadjuvant chemotherapy-radiation therapy followed by surgery. Materials and Methods This retrospective study included 517 patients with locally advanced rectal cancer evaluated from August 2008 to December 2014. Baseline and posttherapy MRI and follow-up data were retrieved for all patients. After training by using 328 cases with pathologic evaluation of EMVI after therapy, radiologists evaluated baseline MRI for EMVI status in addition to tumor size and characteristics, nodal status, and invasion of the mesorectal fascia. Reader reproducibility was determined by using κ coefficient. Kaplan-Meier curves and adjusted Cox models were used to determine the relationship of baseline MRI parameters to overall survival, metastasis-free survival, and local relapse-free survival. Results Among 517 patients, 335 (64.8%) were men; the mean age was 55.6 years ± 11.5 (standard deviation). At baseline, radiologists identified 259 of 517 (50%) patients with EMVI by using MRI. In adjusted analysis, EMVI and mesorectal fascial invasion at baseline MRI were predictors of metastasis-free survival (hazard ratio, 0.3 and 0.6; P ˂ .01 and P ˂ .02, respectively) and overall survival (hazard ratio, 0.5 and 0.5; P = .01 and P = .02, respectively). EMVI was the only factor associated with local relapse-free survival (hazard ratio, 0.3; P ˂ .01). The κ coefficient for determination of EMVI was 0.80. Conclusion Extramural venous invasion (EMVI) can be reliably evaluated with MRI. The presence of EMVI was associated with greater risk of local and distant tumor recurrence and overall death in patients with locally advanced rectal cancer treated with neoadjuvant chemotherapy-radiation therapy. © RSNA, 2018 Online supplemental material is available for this article.

The prognostic significance of extramural venous invasion detected by multiple-row detector computed tomography in stage III gastric cancer.

To determine the 1-year progression-free survival (PFS) of extramural venous invasion (EMVI), detected with contrast-enhanced multiple-row detector computed tomography (ceMDCT), in patients with stageIIIgastric cancer. Between January 2009 and December 2013, 117 patients with pathological-proved stageIIIgastric cancer based on the criteria of the AJCC 7th were included in this retrospective study. All patients underwent adjuvant chemotherapy postoperatively and had been monitored with the follow-up chest/abdomen/pelvis ceMDCT on 3, 6, and 12months post-operation. Two radiologists reviewed preoperative images regarding the presence of EMVI, categories of tumor and categories of lymph node. Conventional prognostic histological factors including pathological T/N status, tumor location/growth pattern, histological type/tumor differentiation, and tumor size were also recorded. Disease progression was defined as the presence of radiological or/and pathology-confirmed metachronous metastases, local recurrence, or gastric cancer-related death. The 1-year PFS for both EMVI-positive and EMVI-negative was calculated using the Kaplan-Meier product limit. Hazard ratios for 1-year PFS were generated using a Cox proportional hazard regression on ceMDCT tumor characteristics. The prevalence of EMVI detected with ceMDCT was 43.6% (51/117) in patients with stageIIIgastric cancer. The EMVI-positive patients had significantly lower 1-year PFS rates (45.1%), than the EMVI-negative patients (75.8%), (Log-rank test, P=0.0008). In a Cox proportional hazards regression analysis, EMVI and tumor location/growth pattern were identified as independent prognostic factors of 1-year PFS with hazard ratio of 2.272 (95% CI 1.133-4.556, P=0.021) and 1.982 (95% CI 1.040-3.780, P=0.039), respectively. EMVI status, detected with ceMDCT, could be used to counsel patients regarding ongoing risks of metastatic disease, implications for surveillance, and systemic chemotherapy.

Systematic review of prognostic importance of extramural venous invasion in rectal cancer

To systematically review the survival outcomes relating to extramural venous invasion in rectal cancer. A systematic review was conducted using PRISMA guidelines. An electronic search was carried out using MEDLINE, EMBASE, CINAHL, Cochrane library databases, Google scholar and PubMed until October 2014. Search terms were used in combination to yield articles on extramural venous invasion in rectal cancer. Outcome measures included prevalence and 5-year survival rates. These were graphically displayed using Forest plots. Statistical analysis of the data was carried out. Fourteen studies reported the prevalence of extramural venous invasion (EMVI) positive patients. Prevalence ranged from 9%-61%. The pooled prevalence of EMVI positivity was 26% [Random effects: Event rate 0.26 (0.18, 0.36)]. Most studies showed that EMVI related to worse oncological outcomes. The pooled overall survival was 39.5% [Random effects: Event rate 0.395 (0.29, 0.51)]. Historically, there has been huge variation in the prevalence of EMVI through inconsistent reporting. However the presence of EMVI clearly leads to worse survival outcomes. As detection rates become more consistent, EMVI may be considered as part of risk-stratification in rectal cancer. Standardised histopathological definitions and the use of magnetic resonance imaging to identify EMVI will improve detection rates in the future.

A Comprehensive Study of Extramural Venous Invasion in Colorectal Cancer.

Colorectal cancer is a common malignancy and a leading cause of cancer related death. Cancer staging following resection is key to determining any adjuvant therapy in those patients with high risk disease. In colorectal cancer, tumour stage and lymph node stage are the main pathological factors which have been considered to influence outcome. Increasing emphasis is now being placed on other factors, especially the presence of extramural venous invasion (EMVI). It is important to understand the relationship of EMVI with other pathological factors and to confirm that in an individual centre that EMVI is being detected at an appropriate rate and is of prognostic significance. This comprehensive study assesses the reporting and prognostic significance of EMVI in a single centre, using prospectively collected data from histopathology reports of a cohort of 2405 patients who underwent surgery for colorectal cancer over a nine year period. Overall, EMVI was reported in 27.9% of colorectal cancer excision specimens. In tumours (n = 1928) that had not received neoadjuvant therapy, the presence of EMVI varied significantly depending on tumour site (χ2 = 12.03, p<0.005), tumour stage (χ2 = 268.188, p<0.001), lymph node stage (χ2 = 294.368, p<0.001) and Dukes’ stage (χ2 = 253.753, p<0.001). Multivariate analysis confirmed EMVI as a significant independent prognostic indicator (p<0.001). In conclusion, the presence of EMVI as an independent prognostic indicator is shown and is related to other pathological and prognostic factors. This study emphasises the requirement for the accurate identification of EMVI in colorectal cancer excision specimens and also understanding the relationship of EMVI with other prognostic factors.

Increased lymph node yield in colorectal cancer is not necessarily associated with a greater number of lymph node positive cancers.

The presence of lymph node metastasis is a key prognostic factor in colorectal cancer and lymph node yield is an important parameter in assessing the quality of histopathology reporting of colorectal cancer excision specimens. This study assesses the trend in lymph node evaluation over time in a single institution and the relationship with the identification of lymph node positive tumours. It compares the lymph node yield of a contemporary dataset compiled from the histopathology reports of 2178 patients who underwent surgery for primary colorectal cancer between 2005 and 2012 with that of a historic dataset compiled from the histopathology reports of 1038 patients who underwent surgery for colorectal cancer at 5 yearly intervals from 1975 to 2000. The mean lymph node yield was 14.91 in 2005 rising to 21.38 in 2012. In 2012 92.9% of all cases had at least 12 lymph nodes examined. Comparison of the mean lymph node yield and proportion of Dukes C cases shows a significant increase (Pearson correlation = 0.927, p = 0.001) in lymph node yield while there is no corresponding significant trend in the proportion of Dukes C cases (Pearson correlation = −0.138, p = 0.745). This study shows that there is increasing yield of lymph nodes from colorectal cancer excision specimens. However, this is not necessarily associated with an increase number of lymph node positive cancers. Further risk stratifying of colorectal cancer requires consideration of other pathological parameters especially the presence of extramural venous invasion and relevant biomarkers.

Developments in the assessment of venous invasion in colorectal cancer: implications for future practice and patient outcome

Venous invasion, or "large vessel" invasion, is a known independent prognostic indicator of distant recurrence and survival in colorectal cancer. Accurate assessment of venous invasion is of particular importance in stage II disease because it may influence the decision to administer adjuvant therapy. Venous invasion is widely believed to be an underreported finding with significant variability in its reported incidence. In the most recent College of American Pathologists' cancer reporting protocol, venous invasion is not recorded separately from lymphovascular, or "small vessel" invasion, which may not be appropriate because these features confer differing prognostic information. The presence of extramural venous invasion is strongly predictive of adverse outcome, although the prognostic significance of intramural venous invasion remains unknown. There are no formal guidelines regarding the pathologic assessment of venous invasion or the application of specific reporting criteria. The routine use of an elastic stain results in an almost 3-fold increase in the venous invasion detection rate when compared with a standard hematoxylin and eosin stain and may be a cost-effective means of increasing the diagnostic yield of venous invasion. The development of high-resolution magnetic resonance imaging, where extramural venous invasion can be detected preoperatively, may also influence the manner in which pathologists process specimens. This review focuses on recent developments in the assessment of venous invasion and highlights their potential impact on future practice.

What Impact Has the Introduction of a Synoptic Report for Rectal Cancer Had on Reporting Outcomes for Specialist Gastrointestinal and Nongastrointestinal Pathologists?

Synoptic pathology reports increase the completeness of reporting for colorectal cancer. Despite the perceived superiority of specialist reporting, service demands dictate that general pathologists report colorectal cancer specimens in many centers. To determine differences in the completeness of rectal cancer reporting between specialist gastrointestinal and nongastrointestinal pathologists in both the narrative and synoptic formats. Pathology reports from rectal cancer resections performed between 1997 and 2008 were reviewed. A standardized, synoptic report was formally introduced in 2001. Reports were assessed for completeness according to 10 mandatory elements from the College of American Pathologists checklist. Overall, synoptic reports (n = 315) were more complete than narrative reports (n = 183) for TNM stage, distance to the circumferential radial margin, tumor grade, lymphovascular invasion, extramural venous invasion, perineural invasion, and regional deposits (all P < .01). Compared with those by nonspecialist pathologists, narrative reports by gastrointestinal pathologists were more complete for lymphovascular invasion (59.3% versus 35.9%, P = .02) and extramural venous invasion (70.4% versus 35.9%, P = .001), but there was no difference in completeness once a synoptic report was adopted. Gastrointestinal pathologists tended to report the presence of extramural venous invasion more frequently in both the narrative (18.5% versus 5.1%, P = .01) and synoptic formats (25.5% versus 14.6%, P = .02). Completeness of reporting, irrespective of subspecialist interest, was dramatically increased by the use of a synoptic report. Improvements in completeness were most pronounced among nongastrointestinal pathologists, enabling them to attain a level of report completeness comparable to that of gastrointestinal pathologists. Further studies are required to determine whether there are actual discrepancies in the detection of prognostic features between specialist gastrointestinal and nongastrointestinal pathologists.

Induction chemotherapy with or without chemoradiation in intermediate-risk rectal cancer patients defined by magnetic resonance imaging (MRI): A GEMCAD study.

TPS196 Background: Different treatment strategies may be indicated for intermediate-risk (T1–2N1, T3N0) versus moderately high- (T1–2N2, T3N1,T4N0) or high-risk patients (T3N2, T4N1–2) based on differential survival rates and rates of relapse (Gunderson et al JCO 22: 1785-1796, 2004). T3 tumors are prognostically inhomogeneous and patients with extramural penetration > 5 mms and extramural venous invasion (EMVI) are associated with increased risk of local relapse but especially with distant failure. Thin-slice high-resolution MRI can identify those patients accurately (Smith NJ. Br J Surg. 2008 95:229-36). Bevacizumab monotherapy has significant antivascular and vascular normalizing effects in rectal cancer (Willett et al. J Clin Oncol 27:3020-3026, 2009) and in combination with capecitabine and oxaliplatin (CAPOX) is a standard treatment for metastatic disease. Purpose: To evaluate the efficacy of induction CAPOX/bevacizumab with selective chemo/radiotherapy (CT/RT) in patients with intermediate-risk (T3) rectal adenocarcinoma. Methods: Main eligibility criteria: 1. Patient with measurable disease at the baseline visit. 2. Tumor that meets all the following criteria in MRI (3-mm slices) of the pelvis: Distal border of tumor > 5 cm from the external edge of the anus and below the sacral promontory and tumor ≥2 mm from the mesorectal fascia and one or both of the following: T3 > 5 mm extramural penetration or presence of EMVI. 3. Candidate for R0 surgery with sphincter preservation surgery. All pre- and post-treatment MRI scans are reviewed independently by one radiologist (G.B.). Treatment: Induction CAPOX with bevacizumab are given for 3 cycles over 9 weeks and one additional cycle without bevacizumab. Patients undergo re-staging within 3 weeks of their 4th cycle with MRI. Those who respond (i.e. complete or partial response) proceed to surgery between 4-6 weeks from the last chemotherapy dose. Patients with stable or progressive disease receive capecitabine/radiation. Design: Simon 2-stage: α=0.1 β=0.1; 28 evaluable pts 1st stage and 41 evaluable pts for 2nd stage. Primary Endpoint: Response rate (RECIST). To date 12 patients have been registered. No significant financial relationships to disclose.