Persistent High Rate of Positive Margins and Postoperative Complications After Surgery for cT4 Rectal Cancer at a National Level

Impact of hospital volume on survival in patients with locally advanced colon cancer - A Dutch population-based study

AIM

Locally advanced colon cancer (LACC) often necessitates complex prognosis-determining treatment. This study investigated the impact of hospital volume on short- and long-term outcomes following surgery for LACC.

METHOD

Data involving all patients with LACC categorized as clinical T4 and/or N2, between 2015 and 2019 in the Netherlands, were extracted from the Netherlands Cancer Registry. Hospitals were stratified into low volume (1-19 LACC resections per year), medium volume (20-29 LACC resections per year) and high volume (≥30 LACC resections per year). Data were analysed using Kaplan-Meier curves, logistic regression analysis and Cox-regression models.

RESULTS

A total of 49 298 patients were diagnosed with colon cancer, of whom 9206 (18.7%) had locally advanced disease. Of these 9206 patients, resection was performed in 8537 with a median age of 71 (interquartile range: 63-78) years. Patients were more likely to undergo laparoscopic procedures in high-volume hospitals than in low-volume hospitals (OR = 1.28, 95% CI: 1.12-1.46). No risk differences in anastomotic leakage or postoperative 90-day mortality were observed according to hospital volume. Five-year overall survival rates were comparable among high-, medium- and low-volume hospitals (58.7% vs. 58.0% vs. 60.0%, p = 0.62). Hospital volume was not associated with overall survival in multivariable analysis. Independent predictors of worse overall survival included older age, higher American Society of Anaesthesiologists score, emergency/urgent setting, anastomotic leakage, higher pTNM status, involved resection margins and no adjuvant chemotherapy.

CONCLUSION

Despite the complexity of surgical treatment, hospital volume was not associated with survival in LACC. Hospital volume might be an imperfect surrogate for quality assessment.

Survival after surgery beyond total mesorectal excision for primary locally advanced rectal cancer, a population-based study

BACKGROUND

The aim of this study was to compare relative survival in non-metastatic rectal cancer clinically staged as T3-T4 requiring beyond total mesorectal excision (TME) to that after standard TME.

METHODS

This population-based study included all patients operated with anterior resection, abdominoperineal excision or Hartmann's procedure for non-metastatic rectal cancer clinically staged as T3-T4 in Sweden between 2009 and 2018. Relative survival was analysed in relation to surgery beyond TME (bTME), which was subcategorized as bTME- and bTME + to account for extent of resection. In all survival analyses, follow-up started at 90 days after surgery. Based on a causal model defined a priori excess mortality rate ratios (EMRR) were estimated using Poisson regression.

RESULTS

Of 8272 included patients 1220 (14.7 %) were operated bTME. In a model adjusted for age and sex bTME was associated with higher excess mortality compared to standard TME (EMRR: 1.76, 95%CI:1.52-2.04). This association persisted after additional adjustment for tumour characteristics, neoadjuvant therapy and hospital volume (EMRR: 1.32, 95%CI:1.11-1.56) and was mainly attributable to restricted relative survival after bTME- (EMRR: 1.42, 95%CI:1.18-1.72) as EMRR after bTME+ was 1.07 (95%CI:0.80-1.44).

CONCLUSION

This national population-based study showed inferior relative survival after bTME compared to standard TME in non-metastasized rectal cancer cT3-cT4. Unexpectedly this difference was mainly seen after bTME of limited extent.

Short-term results in a population based study indicate advantage for minimally invasive rectal cancer surgery versus open

BACKGROUND

The aim of this study was to determine if minimally invasive surgery (MIS) for rectal cancer is non-inferior to open surgery (OPEN) regarding adequacy of cancer resection in a population based setting.

METHODS

All 9,464 patients diagnosed with rectal cancer 2012-2018 who underwent curative surgery were included from the Swedish Colorectal Cancer Registry.

PRIMARY OUTCOMES

Positive circumferential resection margin (CRM < 1 mm) and positive resection margin (R1). Non-inferiority margins used were 2.4% and 4%.

SECONDARY OUTCOMES

30- and 90-day mortality, clinical anastomotic leak, re-operation < 30 days, 30- and 90-day re-admission, length of stay (LOS), distal resection margin < 1 mm and < 12 resected lymph nodes. Analyses were performed by intention-to-treat using unweighted and weighted multiple regression analyses.

RESULTS

The CRM was positive in 3.8% of the MIS group and 5.4% of the OPEN group, risk difference -1.6% (95% CI -1.623, -1.622). R1 was recorded in 2.8% of patients in the MIS group and in 4.4% of patients in the OPEN group, risk difference -1.6% (95% CI -1.649, -1.633). There were no differences between the groups in adjusted unweighted and weighted analyses. All analyses demonstrated decreased mortality and re-admissions at 30 and 90 days as well as shorter LOS following MIS.

CONCLUSIONS

In this population based setting MIS for rectal cancer was non-inferior to OPEN regarding adequacy of cancer resection with favorable short-term outcomes.

Predictors of Definitive Treatment Interruptions of Long-Course Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer

Introduction To identify predictors of definitive treatment interruptions (DTI) of the neoadjuvant long-course radiotherapy (LCRT) in locally advanced rectal cancer (LARC), and to determine their impact on clinical outcomes. Methods Patients with stage II-III LARC treated between 2009-2018 were retrospectively analyzed (n=101, median FU 49.5 months). Logistic regression models evaluated the impact of relevant clinical variables on grade 3 or greater (G3+) acute toxicity, definitive treatment interruption (DTI), pCR, and definitive ostomy (dOST) rates. The secondary outcomes were LRC, MFS, PFS, CSS, and OS. Results The incidences of grade 3 and 4 toxicities were 25.3%, and 1.1%, respectively. The most common G3+ toxicities were peri-anal dermatitis (14.7%) and diarrhea (7.4%), which were more frequent in females (p=0.040) and tumors close to the anal verge (p=0.019). In this study, 11 patients (10.9%) developed DTI, which was associated with these G3+ events (p<0.001). Resection occurred after 7.1 weeks (median, IQR:6.1-8.9). Downstaging occurred in 57.4% (17.8% pCR), 88% achieved negative margins and the dOST rate was 56.4%. The five-year LRC, MFS, PFS, CSS and OS were: 94.4%, 78.9%, 74.7%, 85.2% and 81.6%, respectively. DTI events did not impact any outcome. The factors associated with loco-regional failure were close/positive margins (p<0.001) and stage ypIII (p=0.002). Conclusions: Tumors close to the anal verge and female sex were associated with increased G3+ toxicity, which was predictive of DTI. The resultant partial/complete omission of the planned boost, however, dose did not increase the chance of LR. Further studies to clarify the benefit and optimal timing to deliver the boost are warranted, especially for positive margins.

Impact of Age on Multimodality Treatment and Survival in Locally Advanced Rectal Cancer Patients

Background: Optimal treatment for locally advanced rectal cancer is neoadjuvant (chemo)radiation followed by radical surgery. This is challenging in the aging population because of frequently concomitant comorbidity. We analyzed whether age below and above 70 years is associated with differences in treatment strategy and outcome in this population-based study. Methods: Data between 2008 and 2016 were extracted from the Netherlands Cancer Registry with follow-up until 2021. Differences in therapy, referral and outcome were analyzed using χ2 tests, multivariable logistic regression and relative survival analysis. Results: In total, 6524 locally advanced rectal cancer patients were included. A greater proportion of patients <70 years underwent resection compared to older patients (89% vs. 71%). Patients ≥70 years were more likely treated with neoadjuvant radiotherapy (OR 3.4, 95% CI 2.61−4.52), than with chemoradiation (OR 0.3, 95% CI 0.23−0.37) and less often referred to higher volume hospitals for resection (OR 0.7, 95% CI 0.51−0.87). Five-year relative survival after resection following neoadjuvant therapy was comparable and higher for both patients <70 years and ≥70 years (82% and 77%) than after resection only. Resection only was associated with worse survival in the elderly compared to younger patients (56% vs. 75%). Conclusion: Elderly patients with locally advanced rectal cancer received less intensive treatment and were less often referred to higher volume hospitals for surgery. Relative survival was good and comparable after optimal treatment in both age groups. Effort is necessary to improve guideline adherence, and multimodal strategies should be tailored to age, comorbidity and performance status.

Regional variance in treatment and outcomes of locally invasive (T4) rectal cancer in Australia and New Zealand: analysis of the Bi-National Colorectal Cancer Audit

Backgrounds

Locally invasive T4 rectal cancer often requires neoadjuvant treatment followed by multi‐visceral surgery to achieve a radical resection (R0), and referral to a specialized exenteration quaternary centre is typically recommended. The aim of this study was to explore regional variance in treatment and outcomes of patients with locally advanced rectal cancer in Australia and New Zealand (ANZ).

Methods

Data were collected from the Bi‐National Colorectal Cancer Audit (BCCA) database. Rectal cancer patients treated between 2007 and 2019 were divided into six groups based on region (state/country) using patient postcode. A subset analysis of patients with T4 cancer was performed. Primary outcomes were positive circumferential resection margin (CRM+), and positive circumferential and/or distal resection margin (CRM/DRM+).

Results

A total of 9385 patients with rectal cancer were identified, with an overall CRM+ rate of 6.4% and CRM/DRM+ rate of 8.6%. There were 1350 patients with T4 rectal cancer (14.4%). For these patients, CRM+ rate was 18.5%, and CRM/DRM+ rate was 24.1%. Significant regional variation in CRM+ (range 13.4–26.0%; p = 0.025) and CRM/DRM+ rates (range 16.1–29.3%; p = 0.005) was identified. In addition, regions with higher CRM+ and CRM/DRM+ rates reported lower rates of multi‐visceral resections: range 24.3–26.8%, versus 32.6–37.3% for regions with lower CRM+ and CRM/DRM+ rates (p < 0.0001).

Conclusion

Positive resection margins and rates of multi‐visceral resection vary between the different regions of ANZ. A small subset of patients with T4 rectal cancer are particularly at risk, further supporting the concept of referral to specialized exenteration centres for potentially curative multi‐visceral resection.

Predictors of undergoing multivisceral resection, margin status and survival in Dutch patients with locally advanced colorectal cancer

BACKGROUND

The aim of this nationwide observational study was to evaluate factors associated with multivisceral resection (MVR), margin status and overall survival in locally advanced colorectal cancer (CRC).

MATERIAL AND METHODS

Patients with (y)pT4, cM0 CRC between 2006 and 2017 were selected from the Netherlands Cancer Registry. Cox-proportional hazards modelling was used for survival analysis, stratified for T4a and T4b. Annual hospital volume cut-off was 75 for colon and 40 for rectal resections.

RESULTS

A total of 11.930 patients were included and 2410 patients (20.2%) underwent MVR. Factors associated with MVR for colon and rectal cancer besides cT4 category were more recent diagnosis (OR 3.61, CI 95% 3.06-4.25 (colon) and OR 2.72, CI 95% 1.82-4.08 (rectum)) and high hospital volume (OR 1.20, CI 95% 1.05-1.38 (colon) and OR 2.17, CI 95% 1.55-3.04 (rectum)). Patients ≥70 year were less likely to undergo MVR for colon cancer (OR 0.80, 95% CI 0.70-0.90). Risk factors for incomplete resection were cT4 (OR 3.08, CI 95% 2.35-4.04 (colon) and OR 1.82, CI 95% 1.13-2.94 (rectum)) and poor/undifferentiated tumors (OR 1.41, CI 95% 1.14-1.72 (colon) and OR 1.69, CI 95% 1.05-2.74 (rectum)). More recent diagnosis was independently associated with less incomplete resections in colon cancer (OR 0.58, CI 95% 0.40-0.76). Independent predictors of survival were age, resection margin, nodal status and adjuvant chemotherapy, but not MVR.

CONCLUSION

Treatment of locally advanced CRC with MVR at population level was influenced by year of diagnosis and hospital volume. Margin status in colon cancer improved substantially over time.