Prediction of pathologic staging with magnetic resonance imaging after preoperative chemoradiotherapy in rectal cancer: Pooled analysis of KROG 10-01 and 11-02

Background and purposeThe reported overall accuracy of MRI in predicting the pathologic stage of nonirradiated rectal cancer is high. However, the role of MRI in restaging rectal tumors after neoadjuvant CRT is contentious. Thus, we evaluate the accuracy of restaging magnetic resonance imaging (MRI) for rectal cancer patients who receive preoperative chemoradiotherapy (CRT).Methods and materialsWe analyzed 150 patients with locally advanced rectal cancer (T3–4N0–2) who had received preoperative CRT. Pre-CRT MRI was performed for local tumor and nodal staging. All patients underwent restaging MRI followed by total mesorectal excision after the end of radiotherapy. The primary endpoint of the present study was to estimate the accuracy of post-CRT MRI as compared with pathologic staging.ResultsPathologic T classification matched the post-CRT MRI findings in 97 (64.7%) of 150 patients. 36 (24.0%) of 150 patients were overstaged in T classification, and the concordance degree was moderate (k = 0.33, p < 0.01). Pathologic N classification matched the post-CRI MRI findings in 85 (56.6%) of 150 patients. 54 (36.0%) of 150 patients were overstaged in N classification. 26 patients achieved downstaging (ycT0–2N0) on restaging MRI after CRT. 23 (88.5%) of 26 patients who had been downstaged on MRI after CRT were confirmed on the pathological staging, and the concordance degree was good (k = 0.72, p < 0.01).ConclusionsRestaging MRI has low accuracy for the prediction of the pathologic T and N classifications in rectal cancer patients who received preoperative CRT. The diagnostic accuracy of restaging MRI is relatively high in rectal cancer patients who achieved clinical downstaging after CRT.     

MRI assessment and outcomes in patients receiving neoadjuvant chemotherapy only for primary rectal cancer: long-term results from the GEMCAD 0801 trial

BackgroundPrimary chemotherapy has been tested as a possible approach for patients with high risk features but predicted clear mesorectal margins on preoperative MRI assessment. This study investigates the prognostic relevance of baseline and post-treatment MRI and pathology staging in rectal cancer patients undergoing primary chemotherapy.Patients and methodsForty-six patients with T3 tumour > =2 mm from the mesorectal fascia were prospectively treated with Neoadjuvant Capecitabine, Oxaliplatin and Bevacizumab prior to surgery between 2009 and 2011. The baseline and post-treatment MRI: T, Nodal and Extra-mural venous invasion (EMVI) status were recorded as well as post-treatment MRI Tumour regression grade (TRG) and modified-RECIST assessment of tumour length. The post-treatment pathology (yp) assessments of T3 substage, N, EMVI and TRG status were also recorded. Three-year disease-free survival (DFS) and cumulative incidence of recurrence were estimated by using the Kaplan–Meier product-limit method, and Cox proportional hazards models were used to determine associations between staging and response on MRI and pathology with survival outcomes.ResultsAbout 46 patients underwent neoadjuvant chemotherapy alone for high risk margin safe primary rectal cancer. The median follow-up was 41 months, 5 patients died and 11 patients experienced relapse (2 local, 8 distant and 1 both). In total 23/46 patients were identified with MRI features of EMVI at baseline. mrEMVI positive status carried independent prognostic significance for DFS (P = 0.0097) with a hazard ratio of 31.33 (95% CI: 2.3–425.4). The histopathologic factor that was of independent prognostic importance was a final ypT downstage of ypT3a or less, hazard ratio: 14.0 (95% CI: 1.5–132.5).ConclusionsmrEMVI is an independent prognostic factor at baseline for poor outcomes in rectal cancer treated with neoadjuvant chemotherapy while ≤ypT3a is associated with an improvement in DFS. Future preoperative therapy evaluation in rectal cancer patients will need to stratify treatment according to baseline EMVI status as a crucial risk factor for recurrence in patients with predicted CRM clear rectal cancer.     

Extramural venous invasion is a potential imaging predictive biomarker of neoadjuvant treatment in rectal cancer

Background:

Extramural venous invasion (EMVI) is a poor prognostic factor in rectal cancer and identified on magnetic resonance imaging (MRI) (mrEMVI). The clinical relevance of improvement in mrEMVI following neoadjuvant therapy is unknown. This study aimed to demonstrate that regression of mrEMVI following neoadjuvant chemoradiotherapy (CRT) results in improved outcomes and mrEMVI can be used as an imaging biomarker

Methods:

Retrospective analysis of prospectively collected data was conducted examining the staging and post-treatment MRIs of patients who had presented with EMVI-positive rectal cancer. All patients had undergone neoadjuvant CRT and curative surgery. Changes in mrEMVI were graded with a new MRI-based TRG scale–mr-vTRG; and related to disease-free survival (DFS). The study fulfilled Reporting Recommendations for Tumour Marker Prognostic Studies criteria for biomarkers.

Results:

Sixty-two patients were included. Thirty-five patients showed more than 50% fibrosis of mrEMVI (mr-vTRG 1-3); 3-year DFS 87.8% and 9% recurrence. Twenty-seven patients showed less than 50% fibrosis (mr-vTRG 4-5); 3-year DFS 45.8% with 44% recurrence – P<0.0001. On multivariate Cox-regression, only mr-vTRG 4-5 increased risk of disease recurrence – HR=5.748.

Conclusion:

Patients in whom there has been a significant response of EMVI to CRT show improved DFS. Those patients with poor response should be considered for intensive treatment. As an imaging biomarker in rectal cancer, mrEMVI can be used.     

EMVI-positive stage II rectal cancer has similar clinical outcomes as stage III disease following pre-operative chemoradiotherapy

BackgroundStage II rectal cancers comprise a heterogeneous group, and there is significant variability in practise with regards to adjuvant chemotherapy; the survival benefit of chemotherapy is perceived to be <4% in these patients. However, in recent years, the emergence of additional prognostic factors such as extramural venous invasion (EMVI) suggests that there may be sub-stratification of stage II tumours and, further, we may be under-estimating the benefit adjuvant chemotherapy provides in high-risk patients. This study examined the outcomes of patients with stage II and III rectal cancer to determine whether EMVI status influences disease-free survival (DFS).Patients and methodsAn analysis of a prospectively maintained database was conducted of patients presenting with rectal cancer between 2006 and 2012. All patients underwent curative surgery and had no evidence of metastases at presentation. Clinicopathological factors were compared between stage II and III disease. The primary end point was 3-year DFS; univariate and multivariate analysis was carried out using Cox proportional hazards regression models; hazard ratios (HR) with 95% confidence intervals (CIs) were calculated.ResultsFour hundred and seventy-eight patients were included: 233 stage II; 245 stage III. The prevalence of EMVI was 34.9%; 57 stage II patients (24.5%) and 110 stage III patients (44.9%). On multivariate analysis, only EMVI status was a significant factor for DFS. The adjusted HR for EMVI either alone or in combination with nodal involvement was 2.08 (95% CI 1.10–2.95) and 2.74 (95% CI 1.66–4.52), respectively.ConclusionEMVI is an independently poor prognostic factor for DFS for both stage II and stage III rectal cancer. These results demonstrate that there is risk-stratification within stage II tumours which affects prognosis. When discussing the use of adjuvant chemotherapy with patients that have EMVI-positive stage II tumours, these results provide evidence for a similarly increased risk of distant failure as stage III disease without venous invasion.     

Prognostic value of Smac expression in rectal cancer patients treated with neoadjuvant therapy

The objective was to evaluate expression of second mitochondria-derived activator of caspase (Smac) expression before and after treatment in patients treated with preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer and to correlate the clinicopathological characteristics and level of Smac expression with pathologic response and outcome. Expression of biomarker was evaluated by immunohistochemistry in tumor samples from 98 patients with clinical Stage II and III rectal cancer treated with preoperative pelvic radiotherapy plus concurrent chemotherapy. All patients received a standardized total mesorectal excision procedure after a long interval of 4–6 weeks. For Smac, patients with a good response to neoadjuvant CRT tended to have higher pre-therapy levels (P = 0.007). The level of Smac expression decreased after neoadjuvant therapy (P = 0.016). High expression of Smac before CRT, and high Dworak’s tumor regression grade (TRG) were significantly associated with improved 5-year disease-free survival (P < 0.05). Pretreatment nodal status also was significantly associated with 5-year disease-free survival and 5-year local relapse-free survival (P < 0.05). Multivariate analysis confirmed that the pretreatment expression of Smac and Lymph nodal status were independent prognostic factors. Our study suggests that high expression of Smac before neoadjuvant CRT could predict good outcome in locally advanced rectal cancer patients.     

Implications for selecting local excision in locally advanced rectal cancer after preoperative chemoradiation

Local excision may offer the possibility of organ preservation for the management of locally advanced rectal cancer after neoadjuvant chemoradiotherapy (CRT). However, the oncological outcomes of this strategy have been largely associated with the risk of nodal metastases. In this study, Surveillance, Epidemiology, and End Results Program (SEER)-registered rectal cancer patients, and patients from Fudan University Shanghai Cancer Center (FUSCC) after preoperative chemoradiation were combined to analyze the incidence of lymph node metastasis. The results showed that there was a high risk for residual lymph node metastasis among patients even with complete pathologic response of primary tumor after preoperative CRT (12.6–13.2%). However, in the selected group of patients with pre-CRT MRI staging cN0 rectal cancer, there was only one ypN+ case (3.3%) in ypT0–1 group. These results suggest that pre-CRT MRI staging cN0 patients achieved ypT0–1 of bowel wall tumor may be suitable for local resection.     

Induction Chemotherapy and Chemoradiotherapy Combined to ASA vs. Placebo for High-Risk Rectal Cancer: Results of a Randomized Trial

Inductionchemotherapy (IC) followed by chemoradiation (CRT) is an attractive approach in high-risk locally advanced rectal cancer. Additionally, ASA has shown potential to improve outcomes alongside CRT in rectal cancer. The ICAR trial aimed to evaluate the safety and efficacy of IC followed by CRT with or without ASA on MRI tumor response.MethodsSingle-center, double-blind, randomized phase II trial to evaluate induction treatment with CAPOX, followed by capecitabine-based chemoradiotherapy with ASA (arm 1) or placebo (arm 2) in high-risk stage II-III rectal adenocarcinoma staged by MRI. The primary endpoint was MRI tumor regression grade (mrTRG). Secondary endpoints were pathological response, surgical outcomes, postoperative complications, treatment tolerance, DFS, and OS.ResultsBetween January 2018 and August 2019, 27 patients were eligible, 25 (92.5%) completed IC, and 23 patients were randomly assigned (12 to ASA group; 11 to placebo group). In the ASA arm, 3 pts (25%) presented distant disease progression at restaging. Seven patients (30.4%) had cCR after neoadjuvant treatment. All 13 patients submitted to surgery after neoadjuvant treatment underwent R0 resections except for 1 patient with positive CRM, and 12 patients (92.3%) had sphincter preservation. After a median follow-up of 34.9 months, the 2-year DFS was 83.1% and 3-year OS was 81.5%.ConclusionThere was good compliance in both treatment arms and encouraging cCR rate. ASA during CRT was safe but failed to improve on MRI tumor response. The study was closed due to the absence of benefits.     

Neoadjuvant Chemotherapy With mFOLFOXIRI Without Routine Use of Radiotherapy for Locally Advanced Rectal Cancer

IntroductionAlthough neoadjuvant chemo-radiotherapy (CRT) achieves low local recurrence rates in locally advanced rectal cancer (LARC), it raises a lot of concerns about long-term anal and sexual functions. We explored the efficacy of preoperative chemotherapy with mFOLFOXIRI (folinic acid, 5-fluorouracil, oxaliplatin, and irinotecan) in patients with LARC.Patients and MethodsPatients with LARC evaluated by pelvic magnetic resonance imaging (MRI) were enrolled in this trial. All received 4 to 6 cycles of mFOLFOXIRI. MRI was performed to assess clinical response after chemotherapy. Patients with mesorectal fascia-positive or ycT4a/b after re-evaluation would receive radiation before surgery, whereas responders would have immediate total mesorectal excision (TME). Adjuvant chemotherapy with mFOLFOX6 (folinic acid, 5-fluorouracil, and oxaliplatin) was recommended. The primary endpoint was the proportion of tumor downstaging to ypT_0-2N₀M₀. The secondary endpoints were pathologic complete response rate (pCR), 3-year disease-free survival rate, and safety.ResultsOverall, 106 patients were enrolled and received neoadjuvant mFOLFOXIRI chemotherapy. A total of 103 participants underwent TME surgery. Among 103 patients who completed at least 4 cycles of preoperative chemotherapy, 2 received short-term radiation before TME, and 12 underwent long-term CRT after MRI evaluation. The pCR rate was 20.4%, and the tumor downstaging rate was 42.7%. Among patients without preoperative long-term radiotherapy, the pCR rate and tumor downstaging rate were 17.4% and 41.3%, respectively. Among the per-protocol population, the tumor downstaging rate was 48.1%, and the pCR rate was 20.3%. The chemotherapy-related toxicity was well-tolerated.ConclusionNeoadjuvant chemotherapy with mFOLFOXIRI and selective radiation does not seem to compromise outcomes in LARC. It could be a reasonable alternative to CRT in previously untreated patients with LARC.     

The impact of circumferential tumour location on the clinical outcome of rectal cancer patients managed with neoadjuvant chemoradiotherapy followed by total mesorectal excision

AimTo investigate the impact of circumferential tumour location on neoadjuvant chemoradiotherapy (CRT) response and its prognostic value for locally advanced rectal cancer (LARC) patients after CRT and surgery.MethodsA retrospective study was performed on 486 patients with LARC who received neoadjuvant CRT and surgical treatment. The rate of pathological complete response (pCR) and survival among patients with anteriorly, laterally, and posteriorly located tumours were compared. Logistic regression was performed to identify pCR predictors.ResultsThe anterior tumours exhibited the highest pCR rate of 26.7%, which was slightly higher than the 20.0% and 12.3% for lateral and posterior tumours, respectively (P = 0.006). The 5-year Overall survival (OS) rates after CRT were similar among the anterior, lateral, and posterior groups (anterior vs lateral vs posterior: 81.1% vs 89.9% vs 84.1%, P = 0.6368). Multivariate analysis revealed that the circumferential tumour location, post-CRT serum CEA and post-CRT tumour thickness measured by MRI were independently correlated with achieving pCR.ConclusionThis study is the first, to the best of our knowledge, to show that anterior LARC exhibited the highest pCR rate after neoadjuvant CRT. Patients with anterior rectal cancers do not have different prognoses from those with non-anterior cancers if they undergo neoadjuvant CRT.     

PAN-EX: a pooled analysis of two trials of neoadjuvant chemotherapy followed by chemoradiotherapy in MRI-defined,locally advanced rectal cancer

BackgroundEXPERT and EXPERT-C were phase II clinical trials of neoadjuvant chemotherapy (NACT) followed by chemoradiotherapy (CRT) in high-risk, locally advanced rectal cancer (LARC).DesignWe pooled individual patient data from these trials. The primary objective was overall survival (OS) in the intention-to-treat (ITT) population. Prognostic factors were also analysed.ResultsA total of 269 patients were included. Of these, 91.1% completed NACT, 88.1% completed CRT and 240 (89.2%) underwent curative surgery (R0/R1). After a median follow-up of 71.9 months, 5-year progression-free survival (PFS) and OS were 66.4% and 73.3%, respectively. In the group of R0/R1 resection patients, 5-year relapse-free survival (RFS) and OS were 71.6% and 77.2%, respectively, with local recurrence occurring in 5.5% and distant metastases in 20.6% of cases. Significant prognostic factors after multivariate analyses included age, tumour grade and MRI extramural venous invasion (mrEMVI) at baseline, MRI tumour regression grade (mrTRG) after CRT, ypT stage after surgery and adherence to study treatment. mrTRG after NACT was associated with PFS (P = 0.002) and OS (P = 0.018) and appeared to stratify patients based on the incremental benefit from sequential CRT. Among the outcome measures considered, in the subgroup of R0/R1 resection patients, ypT and ypStage had the highest predictive accuracy for RFS (concordance index: 0.6238 and 0.6252, respectively) and OS (concordance index: 0.6094 and 0.6132, respectively).ConclusionsAdministering NACT before CRT could be a potential strategy for high-risk LARC. In this setting, mrTRG after CRT is an independent prognostic factor, while mrTRG after NACT should be tested as a parameter for treatment selection in trials of NACT ± CRT. ypT stage may be a valuable surrogate end point for future phase II trials investigating intensified neoadjuvant treatments in similar patient populations.     

Stepwise neoadjuvant chemoradiotherapy in the management of mid-low locally advanced rectal cancer

BackgroundThis study aimed to compare the treatment response, complications and prognosis in mid-low locally advanced rectal cancer (LARC) patients who underwent stepwise neoadjuvant chemoradiotherapy (SCRT) or traditional neoadjuvant chemoradiotherapy (CRT).MethodsThe medical records of patients with mid-low rectal cancer who underwent SCRT or CRT were retrospectively analyzed. Differences in the treatment response, pathologic complete response (pCR), R0 resection, local recurrence, anastomotic leakage, presacral infection, anal preservation, defunctioning stoma, treatment-emergent adverse events (TEAEs), overall survival (OS) and disease-free survival (DFS) between patients who underwent SCRT and CRT were compared.ResultsA total of 430 medical records were investigated, including 194 patients in the SCRT group and 236 patients in the CRT group. There was no significant difference in the rates of treatment response, pCR, R0 resection, local recurrence, anastomotic leakage, presacral infection, anal preservation or TEAEs between the two groups. However, the rate of defunctioning stoma in the SCRT group was significantly lower than that in the CRT group (20.1% vs. 44.1%, respectively, P < 0.01). Moreover, the median OS time of the SCRT and CRT groups was 44.0 and 50.5 months, respectively (P = 0.17). The median DFS time of the SCRT and CRT groups was 41.0 and 46.8 months, respectively (P = 0.32).ConclusionCompared with the CRT group, the SCRT group had a similar treatment response, local control and long-term prognosis, and more importantly, a portion of the patients in the SCRT group were exempted from excessive radiation.     

Lymph node yield after rectal resection in patients treated with neoadjuvant radiation for rectal cancer: A systematic review and meta-analysis

BackgroundThe lymph node status represents a major prognostic factor in colorectal cancer. However, it was demonstrated that neoadjuvant chemoradiotherapy (CRT) decreases the numbers of lymph nodes in the specimen. Several studies describe less than 12 lymph nodes in the resected specimen of rectal cancer patients after neoadjuvant radiation. This meta-analysis quantifies the influence of neoadjuvant CRT or radiotherapy (RT) only on the lymph node yield in rectal cancer patients.MethodsWe performed a systematic review and searched PubMed, EMBASE and the Cochrane Library without any language restriction from 1st of January 1980 until 31st March 2015. Two reviewers examined all publications independently and extracted the relevant data if the study assessed lymph node counts or positive lymph node yields of patients who received neoadjuvant treatment compared with patients who did not receive neoadjuvant treatment. Meta-analyses were conducted to quantify the mean difference in lymph node yield.ResultsA total of 34 articles (including 37 datasets) were included in the meta-analyses. Neoadjuvant CRT resulted in a mean reduction of 3.9 lymph nodes (95% confidence interval [CI] 3.7–4.1) and an average reduction in harvested positive lymph nodes of 0.7 (95% CI 0.2–1.2) compared with patients who received no neoadjuvant therapy. Individuals who received neoadjuvant RT had, in average, 2.1 lymph node less (95% CI 1.7–2.5) resected compared with their counterparts who received no neoadjuvant treatment.ConclusionsNeoadjuvant CRT or RT only in rectal cancer patients leads to a decrease in lymph node harvest of approximately four and two lymph nodes, respectively. We therefore stress the importance of intensifying all efforts from involved subspecialities (i.e. surgeons and pathologists) to reach the benchmark harvest of 12 resected lymph nodes according to current guidelines.     

Prognostic Impact of Extranodal Extension in Rectal Cancer Patients Undergoing Radical Resection After Preoperative Chemoradiotherapy

BackgroundExtranodal extension (ENE) of nodal metastasis has emerged as an important prognostic factor in many malignancies, including rectal cancer. However, its significance in patients with rectal cancer receiving preoperative chemoradiotherapy (PCRT) has not been extensively investigated. We therefore assessed ENE and its prognostic impact in a large series of consecutive rectal cancer patients with lymph node metastasis after PCRT and curative resection.Patients and MethodsBetween January 2000 and December 2014, a total of 1925 patients with rectal cancer underwent surgical resection after PCRT. Medical records of 469 patients with pathologic node positivity were retrospectively reviewed.ResultsOf the 469 patients, 118 (25.2%) presented with ENE. ENE was observed more frequently in those with advanced tumor stage (higher ypT, ypN, and ypStage), lymphovascular invasion, and perineural invasion. Five-year disease-free survival rate was lower in patients with ENE-positive tumors than those with ENE-negative tumors (36.1% vs. 52.3%, P = .003). Similarly, 5-year overall survival rate was lower in patients with ENE-positive tumors than those with ENE-negative tumors (60.2% vs. 70.6%, P < .001). Multivariate analysis revealed that the presence of ENE was an independent poor prognostic factor for disease-free survival (hazard ratio = 1.412; 95% confidence interval, 1.074-1.857; P = .013) and overall survival (hazard ratio = 1.531; 95% confidence interval 1.149-2.039; P = .004).ConclusionThe presence of ENE in patients with rectal cancer undergoing PCRT is a negative prognostic factor, reflecting poor survival outcome.     

Is lymphovascular invasion degree one of the important factors to predict neoadjuvant chemotherapy efficacy in breast cancer?

Background  

Patients who achieve pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) have favorable disease-free survival rates. A few studies have suggested that lymphovascular invasion degree may play an important role in predicting pCR. This study aims to confirm the role of lymphatic invasion degree in predicting pCR in breast cancer patients after NAC.     

Diagnostic accuracy and prognostic impact of restaging by magnetic resonance imaging after preoperative chemoradiotherapy in patients with rectal cancer

BackgroundThe prognostic role of restaging rectal magnetic resonance imaging (MRI) in patients with preoperative CRT has not been established. The goal of this study was to evaluate the diagnostic accuracy and prognostic role of radiological staging by rectal MRI after preoperative chemoradiation (CRT) in patients with rectal cancer.MethodsA total of 231 consecutive patients with rectal cancer who underwent preoperative CRT and radical resection from January 2008 to December 2009 were prospectively enrolled. The diagnostic accuracy and prognostic significance of post-CRT radiological staging by MRI was evaluated.ResultsThe sensitivity, specificity, positive predictive value, and negative predictive value of radiological diagnosis of good responders (ypTNM stage 0–I) were 32%, 90%, 65%, and 69%, respectively. The overall accuracy of MRI restating for good responders was 68%. The 5-year disease-free survival rates of patients with radiological and pathological TNM stage 0, stage I, and stage II–III were 100%, 94%, and 76%, respectively (P = 0.037), and 97%, 87%, and 73%, respectively (P = 0.007). On multivariate analysis, post-CRT radiological staging by MRI was an independent prognostic factor for disease-free survival.ConclusionRadiological staging by MRI after preoperative CRT may be an independent predictor of survival in patients with rectal cancer.     

Improved response rate in patients with prognostically poor locally advanced rectal cancer after treatment with induction chemotherapy and chemoradiotherapy when compared with chemoradiotherapy alone: A matched case-control study

IntroductionThe addition of induction chemotherapy (ICT) to neoadjuvant chemoradiotherapy (CRT) has the potential to improve outcomes in patients with locally advanced rectal cancer (LARC). However, patient selection is essential to prevent overtreatment. This study compared the complete response (CR) rate after treatment with and without ICT of LARC patients with prognostically poor characteristics.MethodsAll LARC patients who were treated with neoadjuvant CRT, whether or not preceded by ICT, and who underwent surgery or were considered for a wait-and-see strategy between January 2016 and March 2020 in the Catharina Hospital Eindhoven, were retrospectively selected. LARC was defined as any T4 tumour, or a T2/T3 tumour with extramural venous invasion and/or tumour deposits and/or N2 lymph node status, and/or mesorectal fascia involvement (T3 tumours only). Case-control matching was performed based on the aforementioned characteristics.ResultsOf 242 patients, 178 (74%) received CRT (CRT-group) and 64 patients (26%) received ICT followed by CRT (ICT-group). In the ICT-group, 3 patients (5%) did not receive the minimum of three cycles. In addition, in this selected cohort, compliance with radiotherapy was 100% in the ICT-group and 97% in the CRT-group. The CR rate was 30% in the ICT-group and 15% in the CRT-group (p = 0.011). After case-control matching, the CR rate was 28% and 9%, respectively (p = 0.013).ConclusionTreatment including ICT seemed well tolerated and resulted in a high CR rate. Hence, this treatment strategy may facilitate organ preservation and improve survival in LARC patients with prognostically poor characteristics.     

Predictive factors for early distant metastasis after neoadjuvant chemoradiotherapy in locally advanced rectal cancer

BACKGROUNDDistant relapse is the leading cause of cancer-related death in locally advanced rectal cancer. Neoadjuvant chemoradiation (NACRT) followed by surgery inevitably delays delivery of systemic treatment. Some patients show early distant metastasis before systemic treatment.AIMTo identify the most effective treatments. We investigated prognostic factors for distant metastasis, especially early distant metastasis, using the standard treatment paradigm to identify the most effective treatments according to recurrence risk.METHODSFrom January 2015 through December 2019, rectal cancer patients who underwent NACRT for having clinical T 3-4 or clinical N 1-2 disease according to the 8^th American Joint Committee on Cancer staging system were included. Radiotherapy was delivered to the whole pelvis with concomitant chemotherapy. Patients received surgery 6-8 wk after completion of NACRT. Adjuvant chemotherapy was administered at the physician’s discretion. RESULTSA total of 127 patients received NACRT. Ninety-three patients (73.2%) underwent surgery. The R0 resection rate was 89.2% in all patients. Pathologic tumor and node downstaging rates were 41.9% and 76.3%. Half the patients (n = 69) received adjuvant chemotherapy after surgery. The 3-year distant metastasis-free survival (DMFS) and overall survival (OS) rates were 81.7% and 83.5%. On univariate analyses, poorly differentiated tumors, > 5 cm, involvement of mesorectal fascia (MRF), or presence of extramural involvement (EMVI) were associated with worse DMFS and OS. Five patients showed distant metastasis at their first evaluation after NACRT. Patients with early distant metastasis were more likely to have poorly differentiated tumor (P = 0.025), tumors with involved MRF (P = 0.002), and EMVI (P = 0.012) than those who did not. CONCLUSIONEMVI, the involvement of MRF, and poor histologic grade were associated with early distant metastasis. In order to control distant metastasis and improve treatment outcome, selective use of neoadjuvant treatment according to individualized risk factors is necessary. Future studies are required to determine effective treatment strategies for patients at high risk for distant metastasis.     

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.     

直肠癌壁外血管侵犯的临床价值

肠壁外血管侵犯(EMVI)是直肠癌的预后相关因素。既往对于EMVI的评估主要依靠术后病理结果的分析,随着医学影像学技术的发展,MRI可以准确评估EMVI的状态(mrEMVI)。mrEMVI状态是直肠癌重要的预后指标,mrEMVI阳性患者的局部复发、远处转移风险明显较高。本文对EMVI的诊断特点、临床意义和对治疗模式的影响进行综述,对EMVI研究的趋势进行展望。