The CAIRO4 study: the role of surgery of the primary tumour with few or absent symptoms in patients with synchronous unresectable metastases of colorectal cancer--a randomized phase III study of the Dutch Colorectal Cancer Group (DCCG)

Upfront resection versus no resection of the primary tumor in patients with synchronous metastatic colorectal cancer: the randomized phase III CAIRO4 study conducted by the Dutch Colorectal Cancer Group and the Danish Colorectal Cancer Group

BACKGROUND

Upfront primary tumor resection (PTR) has been associated with longer overall survival (OS) in patients with synchronous unresectable metastatic colorectal cancer (mCRC) in retrospective analyses. The aim of the CAIRO4 study was to investigate whether the addition of upfront PTR to systemic therapy resulted in a survival benefit in patients with synchronous mCRC without severe symptoms of their primary tumor.

PATIENTS AND METHODS

This randomized phase III trial was conducted in 45 hospitals in The Netherlands and Denmark. Eligibility criteria included previously untreated mCRC, unresectable metastases, and no severe symptoms of the primary tumor. Patients were randomized (1 : 1) to upfront PTR followed by systemic therapy or systemic therapy without upfront PTR. Systemic therapy consisted of first-line fluoropyrimidine-based chemotherapy with bevacizumab in both arms. Primary endpoint was OS in the intention-to-treat population. The study was registered at ClinicalTrials.gov, NCT01606098.

RESULTS

Between August 2012 and February 2021, 206 patients were randomized. In the intention-to-treat analysis, 204 patients were included (n = 103 without upfront PTR, n = 101 with upfront PTR) of whom 116 were men (57%) with median age of 65 years (interquartile range 59-71 years). Median follow-up was 69.4 months. Median OS in the arm without upfront PTR was 18.3 months (95% confidence interval 16.0-22.2 months) compared with 20.1 months (95% confidence interval 17.0-25.1 months) in the upfront PTR arm (P = 0.32). The number of grade 3-4 events was 71 (72%) in the arm without upfront PTR and 61 (65%) in the upfront PTR arm (P = 0.33). Three deaths (3%) possibly related to treatment were reported in the arm without upfront PTR and four (4%) in the upfront PTR arm.

CONCLUSIONS

Addition of upfront PTR to palliative systemic therapy in patients with synchronous mCRC without severe symptoms of the primary tumor does not result in a survival benefit. This practice should no longer be considered standard of care.

Palliative resection of the primary tumour improves survival in incurable metastatic colorectal cancer

BACKGROUND

Studies show conflicting results on whether primary tumour resection (PTR) in metastatic colorectal cancer (mCRC) prolongs survival. The aim of this study was to analyse prognostic factors and the effects of PTR on overall survival (OS) in mCRC patients.

METHODS

In this population-based cohort study, factors associated with PTR and OS were assessed in 188 mCRC patients with mCRC treated with palliative chemotherapy between 2008 and 2019. The Chi-square test and Mann-Whitney U-test were used to assess factors associated with PTR. The log-rank test was used to compare Kaplan-Meier estimates for OS. Cox regression was used to identify factors predicting OS.

RESULTS

Patients undergoing PTR had significantly better performance status, fewer metastatic sites, lower CEA levels, and more often had left-sided CRC than patients not undergoing PTR. OS was longer in palliative mCRC patients undergoing PTR (P < 0.01) and PTR was an independent variable in the Cox regression analysis (P < 0.05). Median OS was 22.9 ± 1.9 months for the PTR group and 14.5 ± 1.5 months for the non-operated group. Poor performance status and liver metastases were significantly associated with poor prognosis.

CONCLUSION

This study shows that PTR had a positive effect on OS and may be considered in patients suitable for surgery. PTR was offered to palliative mCRC patients with prognostic factors associated with better prognosis.

Prognosis of patients with unresectable stage IV Colon cancer undergoing primary tumor resection: A multicenter study of minimally symptomatic or asymptomatic primary tumor

AIM

To determine the factors affecting survival of patients with unresectable stage IV colon cancer with Primary tumour resection (PTR) as first treatment compared with those with conventional palliative chemotherapy.

METHODOLOGY

Patient with minimally or asymptomatic stage IV colon cancer at diagnosis were identified from prospectively managed database in included centers from 2015 to 2020. Patient with and without PTR performed were followed up. Primary end point was overall survival. Risk factors affecting survival will be analysis by Kaplan Meier statistics and Cox regression analysis. Secondary outcome will be stoma formation, complication rate and reoperation.

RESULTS

162 patients were included in analysis. 68 patients treated with systemic therapy PTR and 94 patients with tumour in-situ before systemic therapy. Baseline demographics including sex, age, functional status, tumour location, site of metastasis, RAS status were similar except there was slightly more liver metastasis on non-resection group (63.2% vs 79.8%). Cox regression analysis found PTR (HR 0.485, 0.302-0.778, p = 0.003)), bone metastasis (HR 3.163, 1.146-6.918, p = 0.004) commencement (HR 0.579, 0.345-0.971, p = 0.038) and completion of systemic therapy (HR 0.310, 0.178-0.539, p = 0.000) are independent factors predicting survival. The median overall survival after PTR vs tumour in-situ is 28 (IQR: 16-47) vs 12 (IQR:6-31) months (p<0.001).

CONCLUSION

Resection of primary tumour is an independent good prognostic factor in relatively asymptomatic stage IV CA colon patients with unresectable metastasis. Resection should be considered as long as the procedure is straight forward and do not impose significant morbidities with careful patient selection.

The impact of primary tumor resection for asymptomatic colorectal cancer patients with unresectable metastases: a systematic review and meta-analysis

BACKGROUND

Whether patients with asymptomatic primary tumors and unresectable metastases of colorectal cancer (CRC) should undergo primary tumor resection (PTR) remains controversial. This study aims to determine the appropriateness of PTR for these individuals by evaluating a number of outcome measures.

METHODS

A systematic literature search was performed. Outcome measures included overall survival, emergency surgery rates, incidence of postoperative complications, time to initiate chemotherapy, conversion rates, and chemotherapy-related toxicities.

RESULTS

Patients who received PTR in addition to chemotherapy had a better overall survival rate than those who only received chemotherapy (HR = 0.62, 95%CI, 0.50-0.78, I2 = 84%, p < 0.00001). In the RCT subgroup, there were no significant differences with a HR of 0.72 (95%CI, 0.45-1.13, I2 = 17%, p = 0.15). More patients in the chemotherapy alone group could be converted to resectable status (OR = 0.47, 95%CI, 0.27-0.82, I2 = 0%, p = 0.008), but the incidence of emergency surgery was 23% (95%CI, 17-29%, I2 = 14%). The risk of chemotherapy-related toxicity was not significantly higher in the PTR group (OR = 1.5, 95%CI, 0.94-2.43, p = 0.09, I2 = 0%), with a 7% incidence of postoperative complications (95%CI, 0-14%, p = 0.05, I2 = 0%). The time to initiate chemotherapy after PTR was approximately 33.06 days (95%CI, 25.55-40.58, I2 = 0%).

CONCLUSION

PTR plus chemotherapy may be associated with improved survival in asymptomatic CRC patients with unresectable metastases. However, PTR did not provide a significant survival benefit in the subgroup of RCTs. Additionally, PTR did not result in a significantly increased risk of chemotherapy-related toxicity, with a postoperative complication rate of approximately 7%, and chemotherapy could be initiated at approximately 33.06 days after PTR. Compared with the PTR plus chemotherapy, chemotherapy alone could result in a significantly higher conversion rate. However, about 23% of patients receiving chemotherapy alone required emergency surgery for primary tumor-related symptoms. The above results needed to be validated in future larger prospective randomized trials.

Primary tumor resection or systemic treatment as palliative treatment for patients with isolated synchronous colorectal cancer peritoneal metastases in a nationwide cohort study

Limited data are available to guide the decision-making process for clinicians and their patients regarding palliative treatment options for patients with isolated synchronous colorectal cancer peritoneal metastases (CRC-PM). Therefore, the aim of this study is to analyze the outcome of the different palliative treatments for these patients. All patients diagnosed with isolated synchronous CRC-PM between 2009 and 2020 (Netherlands Cancer Registry) who underwent palliative treatment were included. Patients who underwent emergency surgery or curative intent treatment were excluded. Patients were categorized into upfront palliative primary tumor resection (with or without additional systemic treatment) or palliative systemic treatment only. Overall survival (OS) was compared between both groups and multivariable cox regression analysis was performed. Of 1031 included patients, 364 (35%) patients underwent primary tumor resection and 667 (65%) patients received systemic treatment only. Sixty-day mortality was 9% in the primary tumor resection group and 5% in the systemic treatment group (P = 0.007). OS was 13.8 months in the primary tumor resection group and 10.3 months in the systemic treatment group (P < 0.001). Multivariable analysis showed that primary tumor resection was associated with improved OS (HR 0.68; 95%CI 0.57-0.81; P < 0.001). Palliative primary tumor resection appeared to be associated with improved survival compared to palliative systemic treatment alone in patients with isolated synchronous CRC-PM despite a higher 60-day mortality. This finding must be interpreted with care as residual bias probably played a significant role. Nevertheless, this option may be considered in the decision-making process by clinicians and their patients.

Primary Tumor Resection for Metastatic Colorectal, Gastric and Pancreatic Cancer Patients: In Search of Scientific Evidence to Inform Clinical Practice

The management of the primary tumor in metastatic colorectal, gastric and pancreatic cancer patients may be challenging. Indeed, primary tumor progression could be associated with severe symptoms, compromising the quality of life and the feasibility of effective systemic therapy, and might result in life-threatening complications. While retrospective series have suggested that surgery on the primary tumor may confer a survival advantage even in asymptomatic patients, randomized trials seem not to definitively support this hypothesis. We discuss the evidence for and against primary tumor resection for patients with metastatic gastrointestinal (colorectal, gastric and pancreatic) cancers treated with systemic therapies and put in context the pros and cons of the onco-surgical approach in the time of precision oncology. We also evaluate current ongoing trials on this topic, anticipating how these will influence both research and everyday practice.

Interregional practice variations in the use of local therapy for synchronous colorectal liver metastases in the Netherlands

BACKGROUND

The aim of this study was to evaluate the Dutch regional practice variation in treatment of synchronous colorectal liver metastases (CRLM) over time and assess their impact on patients survival.

METHODS

Two cohorts of patients with synchronous CRLM were selected from the Netherlands Cancer Registry (NCR). All patients diagnosed between 2014 and 2018 were selected to analyze interregional practice variations in local therapy (LT) with multivariable logistic regression. Overall survival (OS) was assessed for patients diagnosed from 2008 to 2013 using Kaplan Meier method and Cox regression analyses.

RESULTS

The proportion of patients who underwent LT increased from 15.5% to 21.9%. Interregional use of LT varied from 19.1% to 25.0%. Multivariable logistic regression showed significant differences between regions in the use of LT (p = 0.001) in 2014-2018. There was no association between OS and region of diagnosis for patients who underwent LT after correction for confounders.The use of LT for CRLM increased from 15.5% in 2008-2013 to 21.9% in 2014-2018. Three-year OS increased from 16% to 19% respectively.

CONCLUSION

Interregional practice variations have decreased. The remaining differences are not associated with OS. The use of local therapy and 3-year overall survival have increased over time. Local practice should be monitored to prevent undesirable variation in outcomes.

Care Management and Survival of Patients Diagnosed with Synchronous Metastatic Colorectal Cancer: A High-Resolution Population-Based Study in Two French Areas

Population-based studies provide the opportunity to assess the real-world applicability of current clinical practices. The present research evaluated the survival outcomes of different therapeutic strategies for colorectal cancer (CRC) with synchronous metastasis (SM). The differential impact of treatment sequence, viz. whether chemotherapy (CT) or primary tumor resection (PTR) was performed first, was also evaluated. Methods: All CRC cases with SM diagnosed between 2006 and 2016 (N = 3062) were selected from two specialized digestive cancer registries from northwest France. Cox regression analysis was used to assess survival. Multivariable logistic regression was used to examine factors related to the combination of PTR and CT. Results: The longest survival was observed in patients treated by PTR combined with CT (Group 4; N = 1159). Overall survival was 51.80% at one year (95% Confidence Interval (CI) 50.00–53.60%) and 9.40% at five years (95% CI, 8.30–10.60%). Survival did not differ with respect to the order of treatment in multivariable analysis (hazard ratio, 1.05; 95% CI, 0.88–1.24; p = 0.55). Conclusion: Regardless of the sequence of treatment, a PTR + CT offered the best survival in patients with CRC and SM, even though few were eligible for combination therapy (38%).

The role of upfront primary tumor resection in asymptomatic patients with unresectable stage IV colorectal cancer: A systematic review and meta-analysis

BACKGROUND

Controversy exists over the role of upfront primary tumor resection (PTR) in asymptomatic patients with unresectable stage IV colorectal cancer (CRC). The purpose of this study was to evaluate the effect of upfront PTR on survival outcomes and adverse outcomes.

METHODS

Searches were conducted on PubMed, EMBASE, Web of Science, and Cochrane Library from inception to August 2021. Studies comparing survival outcomes with or without adverse outcomes between PTR and non-PTR treatments were included. Review Manager 5.3 was applied for meta-analyses with a random-effects model whenever possible.

RESULTS

Overall, 20 studies with 3,088 patients were finally included in this systematic review. Compared with non-PTR, upfront PTR was associated with better 3-year (HR: 0.69, 95% CI, 0.57-0.83, P = 0.0001) and 5-year overall survival (OS) (HR: 0.77, 95% CI, 0.62-0.95, P = 0.01), while subgroup analysis indicated that there was no significant difference between upfront PTR and upfront chemotherapy (CT) group. In addition, grade 3 or higher adverse effects due to CT were more frequent in the PTR group with marginal significance (OR: 1.74, 95% CI, 0.99-3.06, P = 0.05), and other adverse outcomes were comparable.

CONCLUSIONS

PTR might be related to improved OS for asymptomatic patients with unresectable stage IV CRC, whereas receiving upfront CT is a rational alternative without detrimental influence on survival or adverse outcomes compared with upfront PTR.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=272675.

Resection of Asymptomatic Primary Tumor with Synchronous Unresectable Colorectal Metastasis-Is It Reasonable?

As much as 30% of colorectal cancers at presentation may have distant metastasis. Asymptomatic primary tumors in the face of synchronous, unresectable metastasis are usually treated with systemic therapy alone. However, data to support or reject primary tumor resection exists and we are yet to come to a definite conclusion. Multiple randomized trials that attempted to address this question failed to accrue adequate patients. The more recent Japanese trial, however, demonstrated a small detriment in overall survival with primary tumor resection. Early cessation of trial with subsequent underpowered results and lack of representation of rectal tumors are key drawbacks of this study. Finally, a balance has to be struck between the risks of tumor-relatedcomplications on systemic therapy with consequent emergency operative morbidity and that of delays in systemic therapy due to primary tumor resection upfront.

Upfront primary tumour resection and survival in synchronous metastatic colorectal cancer according to primary tumour location and RAS status: Pooled analysis of the Spanish Cooperative Group for the Treatment of Digestive Tumours (TTD)

INTRODUCTION

Retrospective studies and meta-analyses suggest that upfront primary tumour resection (UPTR) confers a survival benefit in patients with asymptomatic unresectable metastatic colorectal cancer (mCRC) undergoing chemotherapy, however a consensus of its role in routine clinical practice in the current era of targeted therapies is lacking. This retrospective study aimed to analyse the survival benefit of UPTR in terms of tumour location and mutational status, in patients with synchronous mCRC receiving chemotherapy and targeted therapy.

PATIENTS AND METHODS

Survival was analysed in a pooled cohort of synchronous mCRC patients treated with a first-line anti-VEGF or anti-EGFR inhibitor in seven trials of the Spanish TTD group, according to UPTR, tumour-sidedness and mutational profiling.

RESULTS

Of 1334 eligible patients, 642 (48%) had undergone UPTR. UPTR was associated with significantly longer overall survival (OS; 25.0 vs 20.3 months; HR 1.30, 95%CI 1.15-1.48; p < 0.0001). UPTR was associated with significant OS benefit in both left-sided (HR 1.38, 95%CI 1.13-1.69; p = 0.002) and right-sided (HR 1.39, 95%CI 1.00-1.94; p = 0.049) tumours, RASwt (HR 1.29, 95%CI 1.05-1.60; p = 0.016) and BRAFwt (HR 1.49, 95%CI 1.21-1.84; p = 0.0002) tumours, and treatment with anti-EGFRs (HR 1.47, 95%CI 1.13-1.92; p = 0.004) and anti-VEGFs (HR 1.25, 95%CI 1.08-1.44; p = 0.003). Multivariate analysis identified number of metastatic sites, RAS status, primary tumour location and UPTR as independent prognostic factors for OS.

CONCLUSION

Considering the selection bias inherent to this study, our results support UPTR before first-line anti-EGFR or anti-VEGF targeted therapy in right and left-sided asymptomatic unresectable synchronous mCRC patients. RAS/BRAF mutational status may also influence UPTR function.

Sixty-Day Mortality of Patients With Metastatic Colorectal Cancer Randomized to Systemic Treatment vs Primary Tumor Resection Followed by Systemic Treatment: The CAIRO4 Phase 3 Randomized Clinical Trial

Importance

The role of primary tumor resection (PTR) in synchronous patients with metastatic colorectal cancer (mCRC) who had unresectable metastases and few or absent symptoms of their primary tumor is unclear. Studying subgroups with low postoperative mortality may identify patients who potentially benefit from PTR.

Objective

To determine the difference in 60-day mortality between patients randomized to systemic treatment only vs PTR followed by systemic treatment, and to explore risk factors associated with 60-day mortality.

Design, Setting, and Participants

CAIRO4 is a randomized phase 3 trial initiated in 2012 in which patients with mCRC were randomized to systemic treatment only or PTR followed by systemic treatment with palliative intent. This multicenter study was conducted by the Danish and Dutch Colorectal Cancer Group in general and academic hospitals in Denmark and the Netherlands. Patients included between August 2012 and December 2019 with histologically proven colorectal cancer, unresectable metastases, and a primary tumor with few or absent symptoms were eligible.

Interventions

Systemic treatment, consisting of fluoropyrimidine-based chemotherapy with bevacizumab vs PTR followed by fluoropyrimidine-based chemotherapy with bevacizumab.

Main Outcomes and Measures

The aim of the current analysis was to compare 60-day mortality rates in both treatment arms. A secondary aim was the identification of risk factors for 60-day mortality in the treatment arms. These aims were not predefined in the study protocol.

Results

A total of 196 patients were included in the intention-to-treat analysis (112 [57%] men; median [IQR] age, 65 [59-70] years). Sixty-day mortality was 3% (95% CI, 1%-9%) in the systemic treatment arm and 11% (95% CI, 6%-19%) in the PTR arm (P = .03). In a per-protocol analysis, 60-day mortality was 2% (95% CI, 1%-7%) vs 10% (95% CI, 5%-18%; P = .048). Patients with elevated serum levels of lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, and/or neutrophils who were randomized to PTR had a significantly higher 60-day mortality than patients without these characteristics.

Conclusions and Relevance

Patients with mCRC who were randomized to PTR followed by systemic treatment had a higher 60-day mortality than patients randomized to systemic treatment. Especially patients randomized to the PTR arm with elevated serum levels of lactate dehydrogenase, neutrophils, aspartate aminotransferase, and/or alanine aminotransferase were at high risk of postoperative mortality. Final study results on overall survival have to be awaited.

Trial Registration

ClinicalTrials.gov Identifier: NCT01606098.

Debulking surgery for malignant tumors: the current status, evidence and future perspectives

Debulking surgery, also called cytoreductive surgery, is a resection of the tumor as much as possible and an intended incomplete resection for unresectable malignant tumors. Since the most important principle in surgical oncology is complete R0 resection, debulking surgery goes against the basic principle and obscures the concept of operability. However, debulking surgery has been advocated for various types of advanced malignant tumors, including gynecological cancers, urological cancers, gastrointestinal cancers, breast cancers and other malignancies, with or without adjuvant therapy. Positive data from randomized trials have been shown in subsets of ovarian cancer, renal cell carcinoma, colorectal cancer and breast cancer. However, recent trials for renal cell carcinoma, colorectal cancer and breast cancer have tended to show controversial results, mainly according to the survival improvement of nonsurgical systemic therapy alone. On the other hand, debulking surgery still has a therapeutic role for slow-growing and borderline malignant tumors, such as pseudomyxoma peritonei and thymomas. The recent understanding of tumor heterogeneity and clonal evolution responsible for malignancy and drug resistance indicates that select patients may obtain prolonged survival by the synergistic effect of debulking surgery and novel systemic therapy. This review aimed to describe the current status and evidence of debulking surgery in a cross-organ manner and to discuss future perspectives in the current era with advances in systemic therapy.

Impact of Primary Tumor Resection on Mortality in Patients with Stage IV Colorectal Cancer with Unresectable Metastases: A Multicenter Retrospective Cohort Study

BACKGROUND

Primary tumor resection (PTR) before commencing systemic chemotherapy in patients with stage IV colorectal cancer and unresectable metastases (mCRC) remains controversial. This study aimed to assess whether PTR before systemic chemotherapy is associated with mortality in mCRC patients, after adjusting for confounding factors, such as the severity of the primary tumor and metastatic lesions.

METHODS

We analyzed hospital-based cancer registries from nine designated cancer hospitals in Fukushima Prefecture, Japan. Patients were divided into two groups (PTR and non-PTR), based on whether PTR was performed as initial therapy for mCRC or not. The primary outcome was all-cause mortality. Kaplan-Meier survival analysis was performed, and survival estimates were compared using the log-rank test. Adjusted hazard ratios were calculated using Cox regression to adjust for confounding factors. All tests were two-sided; P-values < 0.05 were considered statistically significant.

RESULTS

Between 2008 and 2015, 616 mCRC patients were included (PTR: 414 [67.2%]; non-PTR: 202 [32.8%]). The median follow-up time was 18.0 (interquartile range [IQR]: 8.4-29.7) months, and 492 patients (79.9%) died during the study period. Median overall survival in the PTR and non-PTR groups was 23.9 (IQR: 12.2-39.9) and 12.3 (IQR: 6.2-23.8) months, respectively (P < 0.001, log-rank test). PTR was significantly associated with improved overall survival (adjusted hazard ratio: 0.51; 95% confidence interval: 0.42-0.64, P < 0.001).

CONCLUSIONS

PTR before systemic chemotherapy in patients with mCRC was associated with improved survival.

Interaction Between Primary Tumor Resection, Primary Tumor Location, and Survival in Synchronous Metastatic Colorectal Cancer: A Population-Based Study

OBJECTIVES

Location of the primary tumor has prognostic value and predicts the effect of certain therapeutics in synchronous metastatic colorectal cancer. We investigated whether the association between primary tumor resection (PTR) and overall survival (OS) also depends on tumor location.

METHODS

Data on synchronous metastatic colorectal cancer patients from the Netherlands Cancer Registry (n=16,106) and Surveillance, Epidemiology, and End Results (SEER) registry (n=19,584) were extracted. Cox models using time-varying covariates were implemented. Median OS for right-sided colon cancer (RCC), left-sided colon cancer, and rectal cancer was calculated using inverse probability weighting and a landmark point of 6 months after diagnosis as reference.

RESULTS

The association between PTR and OS was dependent on tumor location (P<0.05), with a higher median OS of upfront PTR versus upfront systemic therapy in Netherlands Cancer Registry (NCR) of 1.9 (95% confidence interval: 0.9-2.8), 4.3 (3.3-5.6), and 3.4 (0.6-7.6) months in RCC, left-sided colon cancer and rectal cancer, respectively. In SEER data, the difference was 6.0 (4.0-8.0), 8.0 (5.0-10.0), and 10.0 (7.0-13.0) months, respectively. Hazard plots indicate a higher hazard of death 2 to 3 months after PTR in RCC.

CONCLUSION

Upfront PTR is associated with improved survival regardless of primary tumor location. Patients with RCC appear to have less benefit because of higher mortality during 2 to 3 months after PTR.

The Impact of Primary Tumor Resection on Survival in Asymptomatic Colorectal Cancer Patients With Unresectable Metastases

Purpose

This study was conducted to evaluate the effectiveness of primary tumor resection (PTR) in asymptomatic colorectal cancer (CRC) patients with unresectable metastases using the inverse probability of treatment weighting (IPTW) method to minimize selection bias.

Methods

We selected 146 patients diagnosed with stage IV CRC with unresectable metastasis between 2001 and 2018 from our institutional database. In a multivariate logistic regression model using the patients’ baseline covariates associated with PTR, we applied the IPTW method based on a propensity score and performed a weighted Cox proportional regression analysis to estimate survival according to PTR.

Results

Upfront PTR was performed in 98 patients, and no significant differences in baseline factors were detected. The upweighted median survival of the PTR group was 18 months and that of the non-PTR group was 15 months (P = 0.15). After applying the IPTW, the PTR was still insignificant in the univariate Cox regression (hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.5–1.21). However, in the multivariate weighted Cox regression with adjustment for other covariates, the PTR showed a significantly decreased risk of cancer-related death (HR, 0.61; 95% CI, 0.40–0.94).

Conclusion

In this study, we showed that asymptomatic CRC patients with unresectable metastases could gain a survival benefit from upfront PTR by analysis with the IPTW method. However, randomized controlled trials are mandatory.

Surgery for rectal cancer: Differences in resection rates among hospitals in the Netherlands

AIM

Numerous quality improvement initiatives for rectal cancer surgery have focused on textbook outcome parameters. In these studies, resection rate and patients who did not undergo surgery are not included, but these parameters might help to evaluate the surgical care for rectal cancer. The aim of this study is to assess the variation of non-metastatic rectal cancer resection rates among hospitals and its effect on patient outcomes.

METHODS

All patients diagnosed with non-metastatic rectal cancer between 2013 and 2018 were selected from the Netherlands Cancer Registry. Hospitals were categorized in quartiles according to resection rates. A multivariable logistic analysis was performed to determine variation in resection rate between these quartiles using a logistic regression analysis to correct for confounders. The association between resection rates and survival was analyzed using Kaplan-Meier method and Cox-regression analysis.

RESULTS

A total of 22,530 patients were included in the analysis. Resection rates varied from 68 to 89% between hospitals. After multivariable analysis, resection rate remained significantly different among the quartiles when correcting for several factors (odds ratio (95%Confidence-interval) 1.71 (1.56-1.88), 2.42 (2.19-2.67), and 4.04 (3.61-4.53) for increasing resection rate quartiles, in reference to the lowest quartile). A higher resection rate was associated with better overall survival, in multivariable analysis this survival benefit could no longer be identified.

CONCLUSION

There is a substantial variation in resection rates for rectal cancer among hospitals in the Netherlands with an impact on overall survival. This may be a relevant issue when analyzing the overall quality of rectal cancer care.

Primary Tumor Resection Plus Chemotherapy Versus Chemotherapy Alone for Colorectal Cancer Patients With Asymptomatic, Synchronous Unresectable Metastases (JCOG1007; iPACS): A Randomized Clinical Trial

It remains controversial whether primary tumor resection (PTR) before chemotherapy improves survival in patients with colorectal cancer (CRC) with asymptomatic primary tumor and synchronous unresectable metastases.

Primary Tumor-Related Complications and Salvage Outcomes in Patients with Metastatic Rectal Cancer and an Untreated Primary Tumor

BACKGROUND

For rectal cancer with unresectable metastases, current practice favors omitting interventions directed at the primary tumor in asymptomatic patients.

OBJECTIVE

This study aimed to determine the proportion of patients with primary tumor-related complications, characterize salvage outcomes, and measure survival in patients with metastatic rectal cancer who did not undergo upfront intervention for their primary tumor.

DESIGN

This is a retrospective analysis.

SETTING

This study was conducted at a comprehensive cancer center.

PATIENTS

Patients who presented between January 1, 2008, and December 31, 2015, with synchronous stage IV rectal cancer, an unresected primary tumor, and no prior primary tumor-directed intervention were selected.

MAIN OUTCOME MEASURES

The main outcome measured was the rate of primary tumor-related complications in the cohort that did not receive any primary tumor-directed intervention. The Kaplan-Meier method and Cox regression analysis were used to determine whether complications are associated with survival.

RESULTS

The cohort comprised 358 patients with a median age of 56 years (22-92). Median follow-up was 26 months (range, 1-93 months). Among the 168 patients (46.9%) who eventually underwent elective resection of the primary tumor, the surgery was performed with curative intent in 66 patients (18.4%) and preemptive intent in 102 patients (28.5%). Of the 190 patients who did not undergo an upfront or elective intervention for the primary tumor, 68 (35.8%) experienced complications. Nonsurgical intervention for complications was attempted in 34 patients with an overall success rate of 61.8% (21/34). Surgical intervention was performed in 47 patients (including 13 patients for whom nonsurgical intervention failed): diversion in 26 patients and resection in 21 patients. Of those 47 patients, 42 (89.4%) ended up with a colostomy or ileostomy.

LIMITATIONS

This study was conducted at a single center.

CONCLUSION

A significant proportion of patients with metastatic rectal cancer and untreated primary tumor experience primary tumor-related complications. These patients should be followed closely, and preemptive intervention (resection, diversion, or radiation) should be considered if the primary tumor progresses despite systemic therapy. See Video Abstract at http://links.lww.com/DCR/B400. COMPLICACIONES RELACIONADAS CON EL TUMOR PRIMARIO Y RESULTADOS DE RESCATE EN PACIENTES CON CÁNCER DE RECTO METASTÁSICO Y UN TUMOR PRIMARIO NO TRATADO: Para el cáncer de recto con metástasis no resecables, la práctica actual favorece la omisión de las intervenciones dirigidas al tumor primario en pacientes asintomáticos.Determinar la proporción de pacientes con complicaciones relacionadas con el tumor primario, caracterizar los resultados de rescate y medir la supervivencia en pacientes con cáncer rectal metastásico que no se sometieron a una intervención inicial para su tumor primario.Análisis retrospectivo.Centro oncológico integral.Pacientes que se presentaron entre el 1 de enero de 2008 y el 31 de diciembre de 2015 con cáncer de recto en estadio IV sincrónico, un tumor primario no resecado y sin intervención previa dirigida al tumor primario.Tasa de complicaciones relacionadas con el tumor primario en la cohorte que no recibió ninguna intervención dirigida al tumor primario. Se utilizó el método de Kaplan-Meier y el análisis de regresión de Cox para determinar si las complicaciones están asociadas con la supervivencia.La cohorte estuvo compuesta por 358 pacientes con una mediana de edad de 56 años (22-92). La mediana de seguimiento fue de 26 meses (rango, 1 a 93 meses). Entre los 168 pacientes (46,9%) que finalmente se sometieron a resección electiva del tumor primario, la cirugía se realizó con intención curativa en 66 pacientes (18,4%) y con intención preventiva en 102 pacientes (28,5%). De los 190 pacientes que no se sometieron a una intervención inicial o electiva para el tumor primario, 68 (35,8%) experimentaron complicaciones. Se intentó una intervención no quirúrgica para las complicaciones en 34 pacientes con una tasa de éxito global del 61,8% (21 de 34). La intervención quirúrgica se realizó en 47 pacientes (incluidos 13 pacientes en los que falló la intervención no quirúrgica): derivación en 26 pacientes y resección en 21 pacientes. De esos 47 pacientes, 42 (89,4%) terminaron con una colostomía o ileostomía.Único centro.Una proporción significativa de pacientes con cáncer de recto metastásico y primario no tratado experimentan complicaciones relacionadas con el tumor primario. Se debe hacer un seguimiento estrecho de estos pacientes y considerar la posibilidad de una intervención preventiva (resección, derivación o radiación) si el tumor primario progresa a pesar de la terapia sistémica. Consulte Video Resumen en http://links.lww.com/DCR/B400.

Multimodal Treatment in Metastatic Colorectal Cancer (mCRC) Improves Outcomes-The University College London Hospital (UCLH) Experience

BACKGROUND

Despite notable advances in the management of metastatic colorectal cancer (mCRC) over the last two decades, treatment intent in the vast majority of patients remains palliative due to technically unresectable disease, extensive disease, or co-morbidities precluding major surgery. Up to 30% of individuals with mCRC are considered potentially suitable for primary or metastasis-directed multimodal therapy, including surgical resection, ablative techniques, or stereotactic radiotherapy (RT), with the aim of improving survival outcomes. We reviewed the potential benefits of multimodal therapy on the survival of patients with mCRC treated at the UCLH.

METHODS

Clinical data on baseline characteristics, multimodal treatments, and survival outcomes were retrospectively collected from all patients with mCRC receiving systemic chemotherapy between January 2013 and April 2017. Primary outcome was the impact of multimodal therapy on overall survival, compared to systemic therapy alone, and the effect of different types of multimodal therapy on survival outcome, and was assessed using the Kaplan-Meier approach. All analyses were adjusted for age, gender, and side of primary tumour.

RESULTS

One-hundred and twenty-five patients with mCRC were treated during the study period (median age: 62 years (range 19-89). The liver was the most frequent metastatic site (78%; 97/125). A total of 52% (65/125) had ≥2 lines of systemic chemotherapy. Of the 125 patients having systemic chemotherapy, 74 (59%) underwent multimodal treatment to the primary tumour or metastasis. Median overall survival (OS) was 25.7 months [95% Confidence Interval (CI) 21.5-29.0], and 3-year survival, 26%. Univariate analysis demonstrated that patients who had additional procedures (surgery/ablation/RT) were significantly less likely to die (Hazard Ratio (HR) 0.18, 95% CI 0.12-0.29, p < 0.0001) compared to those receiving systemic chemotherapy alone. Increasing number of multimodal procedures was associated with an incremental increase in survival-with median OS 28.4 m, 35.7 m, and 64.8 m, respectively, for 1, 2, or ≥3 procedures (log-rank p < 0.0001). After exclusion of those who received systemic chemotherapy only (n = 51), metastatic resections were associated with improved survival (adjusted HR 0.36, 95% CI 0.20-0.63, p < 0.0001), confirmed in multivariate analysis. Multiple single-organ procedures did not improve survival.

CONCLUSION

Multimodal therapy for metastatic bowel cancer is associated with significant survival benefit. Resection/radical RT of the primary and resection of metastatic disease should be considered to improve survival outcomes following multidisciplinary team (MDT) discussion and individual assessment of fitness.

Non-curative gastrectomy for advanced gastric cancer does not result in additional risk of postoperative morbidity compared to curative gastrectomy

BACKGROUND

Non-curative gastrectomy (nCG) for gastric cancer can be considered in selected cases to relieve symptoms. The aim of this study was to evaluate postoperative morbidity and mortality in patients who underwent nCG and compare these results with an intended curative gastrectomy (CG).

MATERIALS AND METHODS

All patients who underwent both nCG and CG in the Netherlands were included from the Dutch Upper GI Cancer Audit (2011-2016). In this population-based cohort study postoperative morbidity, mortality, readmissions and short-term oncological outcomes were appraised. Propensity score matching (PSM) was applied to create comparable groups of patients who underwent nCG versus CG, using patient and tumor characteristics.

RESULTS

Of the 2202 eligible patients, 115 patients underwent nCG and 2087 underwent CG. After PSM, 115 nCG-patients were matched to 227 CG-patients. More conversions from laparoscopic to open surgery occurred during nCG (10·4 versus 2·6%, p = 0·007). Although postoperative mortality was higher after nCG in the original cohort (9·6 versus 4·8%, p = 0·026), after PSM there was no difference between groups (9·6 versus 7·0%, p = 0·415). Postoperative morbidity, re-interventions and readmission rates did not differ significantly between groups. Resection of additional organs (30·4 versus 11·5%, p < 0·001) and R+ resections (65·2 versus 12·3%, p < 0·001) occurred more frequently during nCG.

CONCLUSIONS

nCG does not lead to additional postoperative risks compared to CG in patients with similar characteristics, and may be considered in fit patients with advanced gastric cancer. However, randomized trials evaluating potential (survival) benefits of nCG should be awaited.

The Role of Primary Tumor Resection in Colorectal Cancer Patients with Asymptomatic, Synchronous, Unresectable Metastasis: A Multicenter Randomized Controlled Trial

We aimed to assess the survival benefits of primary tumor resection (PTR) followed by chemotherapy in patients with asymptomatic stage IV colorectal cancer with asymptomatic, synchronous, unresectable metastases compared to those of upfront chemotherapy alone. This was an open-label, prospective, randomized controlled trial (ClnicalTrials.gov Identifier: NCT01978249). From May 2013 to April 2016, 48 patients (PTR, n = 26; upfront chemotherapy, n = 22) diagnosed with asymptomatic colorectal cancer with unresectable metastases in 12 tertiary hospitals were randomized (1:1). The primary endpoint was two-year overall survival. The secondary endpoints were primary tumor-related complications, PTR-related complications, and rate of conversion to resectable status. The two-year cancer-specific survival was significantly higher in the PTR group than in the upfront chemotherapy group (72.3% vs. 47.1%; p = 0.049). However, the two-year overall survival rate was not significantly different between the PTR and upfront chemotherapy groups (69.5% vs. 44.8%, p = 0.058). The primary tumor-related complication rate was 22.7%. The PTR-related complication rate was 19.2%, with a major complication rate of 3.8%. The rates of conversion to resectable status were 15.3% and 18.2% in the PTR and upfront chemotherapy groups. While PTR followed by chemotherapy resulted in better two-year cancer-specific survival than upfront chemotherapy, the improvement in the two-year overall survival was not significant.

Comprehensive literature review of randomized clinical trials examining novel treatment advances in patients with colon cancer

The treatment of colon cancer has had numerous recent advances, in terms of surgical approach, adjuvant therapies, and more. In this review, the authors examine randomized clinical trials comparing open surgery to laparoscopic surgery (including total mesocolic excision), and also examine the role of robotic surgery. Novel surgical techniques including the no-touch technique, side-to-side anastomosis, suture technique, complete mesocolic excision (CME) with central vascular ligation (CVL), and natural orifice transluminal endoscopic surgery (NOTES) are outlined. The role of placing endoscopic self-expandable metal stents (SEMS) for colonic obstruction is compared and contrasted with the surgical approach, and the effect that the anti-VEGF inhibitor bevacizumab may have on this side effect profile is further explored. The role of the resection of the primary tumor in the setting of metastatic disease is examined with respect to survival benefit. Pathways of perioperative care which can accelerate post-surgical recovery, including enhanced recovery after surgery (ERAS) are examined. The role of adjuvant chemotherapy in patients with high-risk stage II and patients with stage III disease is examined, along with the role on circulating tumor DNA (ctDNA) as well as with the biologic targeted agents cetuximab and bevacizumab. Lastly, the authors detail the postoperative surveillance schedules after surgical resection with respect to survival outcomes.

Survival outcome of palliative primary tumor resection for colorectal cancer patients with synchronous liver and/or lung metastases: A retrospective cohort study in the SEER database by propensity score matching analysis

BACKGROUND

There is a great matter of controversies whether some of these synchronous metastatic colorectal cancer patients can benefit from palliative primary tumor resection (pPTR) and there is still no reported randomized control trial to address this issue.

METHODS

Patients with microscopically proven metastatic colorectal cancer were identified within the SEER database (2010-2016). Patients were propensity matched 1:1 into pPTR and non-surgery groups and among the matched cohort, the univariable and multivariable Cox proportional hazards regression models were performed to identify predictors of survival. Median survival was calculated by using the Kaplan-Meier method.

RESULTS

Of 21,405 colorectal cancer patients diagnosed with synchronous liver and/or lung metastases, 7386 were identified in the matched cohort. The median overall survival was 12.0 months, 22.0 months in the non-surgery, surgery groups, respectively (p < 0.001) and the corresponding median cancer-specific survival was 13.0 months, 22.0 months, respectively (p < 0.001). Multivariable Cox regression analysis demonstrated that surgery was independently associated with improved overall survival (hazard ratio, 0.531) as well as cancer-specific survival (hazard ratio, 0.516). In stratified analyses by primary site and patterns of distant metastases, those patients with pPTR had better prognosis. In addition, stratified analysis revealed that trimodality therapy was linked with the greatest therapeutic effect followed by addition of chemotherapy to pPTR.

CONCLUSIONS

pPTR may offer some therapeutic benefits among carefully selected patients, and surgery-based multimodality therapy was associated with better survival.

A randomized controlled trial comparing primary tumour resection plus chemotherapy with chemotherapy alone in incurable stage IV colorectal cancer: JCOG1007 (iPACS study)

It is controversial whether chemotherapy with or without primary tumour resection is effective for the patients with incurable Stage IV colorectal cancer. A randomized controlled trial, initiated in Japan in 2012, is being conducted to evaluate the survival benefit and safety of primary tumour resection plus chemotherapy compared with chemotherapy alone in asymptomatic Stage IV colorectal cancer patients with unresectable metastatic disease. Patients are randomly assigned to either chemotherapy alone or primary tumour resection followed by chemotherapy. The primary endpoint is overall survival. Secondary endpoints are progression-free survival, incidence of adverse events, proportion of patients with R0 resection and proportion of palliative surgery for the chemotherapy-alone group. This trial was registered in June 2012 with the UMIN Clinical Trials Registry as UMIN000008147 [http://www.umin.ac.jp/ctr/index-j.htm]. In December 2017, the study protocol was amended for reducing sample size. A total of 280 patients will be enrolled over the course of 8.5 years.

Enhanced metastatic growth after local tumor resection in the presence of synchronous metastasis in a mouse allograft model of neuroblastoma

PURPOSE

We investigated how local tumor resection affects metastatic lesions in neuroblastoma.

METHODS

MYCN Tg tumor-derived cells were injected subcutaneously into 129^+Ter/SvJcl wild-type mice. First, the frequency of metastasis-bearing mice was investigated immunohistochemically (metastatic ratio) at endpoint or post-injection day (PID) 90. Second, the threshold volume of local tumor in mice bearing microscopic lymph node metastasis (mLNM) was investigated at PID 30. Finally, local tumors were resected after exceeding the threshold. Mice were divided into local tumor resection (Resection) and observation (Observation) groups, and the metastatic ratio and volume of LNM were compared between the groups at endpoint or PID 74.

RESULTS

The metastatic ratio without local resection was 88% at PID 78-90. The threshold local tumor volume in the mice with mLNM was 745 mm³ at PID 30, so local tumors were resected after exceeding 700 mm³. The metastatic ratio and LNM volume were significantly greater in the Resection group (n = 16) than in the Observation group (n = 16) (94% vs. 38%, p < 0.001; 2092 ± 2310 vs. 275 ± 218 mm³, p < 0.01; respectively) at PID 50-74.

CONCLUSION

Local tumor resection might augment the growth of synchronous microscopic metastases. Our results provide insights into the appropriate timing of local resection for high-risk neuroblastoma.

Primary Tumor Resection for Stage IV Colorectal Cancer in the Era of Targeted Chemotherapy

BACKGROUND

In the current era of targeted therapies, the benefits of resection of primary tumors in patients with unresectable stage IV colorectal cancer, specifically with regard to overall survival, are unknown.

METHODS

Our study population comprised 208 consecutive patients with unresectable stage IV colorectal cancer who received chemotherapy containing at least one molecular target agent, bevacizumab, cetuximab, and panitumumab, at the National Cancer Center Hospital from 2006 to 2013. To lessen the effects of confounding factors between two treatment groups (resection versus non-resection) such as performance status, presence of severe symptoms, M subcategories (M1a versus M1b, M1c) according to the TNM classification, primary tumor site, and CEA value, we conducted three different propensity score analyses (regression adjustment, stratification, and matching).

RESULTS

Of the 208 patients, 108 (52%) underwent resection of the primary tumor, while 100 (48%) did not. Regression adjustment revealed that resection was not associated with longer overall survival (hazard ratio of 0.70 (95% CI [0.49-1.00]; p = 0.051)). Stratification analysis of five strata revealed inconsistent results (hazard ratios ranged from 0.50 to 1.58); specifically, resection was associated with longer overall survival in four strata, but with shorter survival in one stratum. The propensity score-matched cohort (64 matched pairs) yielded a hazard ratio of 0.76 (95% CI [0.51-1.15]; p = 0.197).

CONCLUSIONS

All three analyses revealed that, in the current era of chemotherapy with target agents, primary tumor resection was only marginally influential and did not significantly improve overall survival over chemotherapy alone.

ACORN: Observational Study of Bevacizumab in Combination With First-Line Chemotherapy for Treatment of Metastatic Colorectal Cancer in the UK

INTRODUCTION

Survival in metastatic colorectal cancer is worse than expected in the United Kingdom. Real-world data are needed to better understand UK-specific treatment practices that may explain this.

PATIENTS AND METHODS

The Avastin ColORectal Non-interventional (ACORN) study is a multicenter, prospective, UK-based, observational, phase 4 study (ClinicalTrials.gov, NCT01506167) that recruited patients with metastatic colorectal cancer scheduled to receive bevacizumab in combination with first-line chemotherapy as part of routine clinical practice. Primary end points included progression-free survival, overall survival (OS), serious adverse events (AEs), and grade 3 to 5 bevacizumab-related AEs.

RESULTS

A total of 714 patients were recruited between August 30, 2012, and February 4, 2014. Median follow-up was 16.4 months. Median first-line chemotherapy duration was 5.6 months, with capecitabine/oxaliplatin (265 [37.1%]) being the most common regimen. Median total chemotherapy duration was 8.1 months and did not vary by geographic location in the UK. Median progression-free survival (95% confidence interval) was 8.7 (8.2-9.1) months, and median OS was 17.8 (16.1-19.3) months. There was no significant difference in efficacy by chemotherapy regimen administered. Ninety-nine patients (13.9%) received bevacizumab after disease progression. The safety profile of bevacizumab was consistent with previous studies.

CONCLUSION

ACORN provided evidence that there were no clear differences observed in outcomes between bevacizumab with capecitabine-based chemotherapy and fluorouracil-based regimens, and confirmed the safety profile of bevacizumab in a real-world UK-based population. The lower-than-expected OS is likely due to the short total chemotherapy duration, less frequent use of bevacizumab after disease progression, and higher rates of in-situ primary tumors.

The impact of postoperative morbidity on survival in patients with metastatic colon and rectal cancer

INTRODUCTION

Avoiding postoperative morbidity is essential in patients with advanced cancer. To further improve treatment in stage IV colorectal cancer, knowledge about risk factors which effect short- and long-term outcomes is important.

METHODS

All stage IV colon and rectal cancer who underwent elective surgery between 2004 and 2015 were included (n = 345). We compared resectable colon and rectal patients, and unresectable colon and rectal cancer patients.

RESULTS

Median follow-up duration was 22.2 (unresectable) and 56.7 months (resectable) with no difference in tumor location. Colon cancer patients were more often considered unresectable (P < .001). Rectal procedures were correlated with a higher morbidity rate and a longer surgical duration (P < .001). In the resectable cohort, obese patients, open procedures and prolonged surgery were independently associated with postoperative complications. Considering the palliative group, neoadjuvant treatment and age were correlated with worse outcomes. Morbidity was not associated with long-term outcomes in the resectable cohort. However, unresectable patients who developed respiratory (hazard ratio [HR]: 7.53) or cardiac (HR: 3.75) complications and patients with an American Society of Anesthesiologists-score III to IV (HR: 1.51) had an impaired survival.

CONCLUSION

Our results emphasize the need for an adequate preoperative assessment to identify patients at risk for postoperative complications and impaired survival.

To resect or not to resect: The hamletic dilemma of primary tumor resection in patients with asymptomatic stage IV colorectal cancer

Primary tumor resection (PTR) in advanced asymptomatic colorectal cancer (CRC) has been a matter of intense debate for long time. With the advances in systemic treatments, this practice has decreased over the years, although it remains still pervasive. Although the removal of primary tumor has been extensively interrogated both in retrospective and prospective studies, it still remains a clinical conundrum. There are many arguments for and against PTR in CRC both from the preclinical and the clinical point of view. Two scoring models have been published aiming at identifying patients who are suitable candidate for PTR, but they deserve further investigations in larger datasets. While awaiting the results of ongoing randomized clinical trials (RCTs) on this controversial topic, both upfront systemic treatment and PTR followed by chemotherapy should be considered valid options in patients with asymptomatic mCRC. Clinical selection and a shared-decision making approach are the keys to success.

A systematic analysis highlighting deficiencies in reported outcomes for patients with stage IV colorectal cancer undergoing palliative resection of the primary tumour

BACKGROUND

Management of the primary tumour in the presence of unresectable metastatic colorectal cancer (mCRC) is controversial. The role of primary tumour resection (PTR) has been investigated by a number of retrospective cohort studies, with a number on going randomised controlled trials. The aim of this study was to identify the clinical and patient-reported outcomes currently reported in studies that evaluate the role of PTR in mCRC.

METHODS

Literature searches were performed in MEDLINE (via OvidSP) (1966-June 2017), EMBASE (via OvidSP) and the Cochrane Library using terms related to colorectal cancer and primary tumour resection. All studies documenting outcomes following palliative PTR were included. Eligible articles were assessed using the Risk of Bias In Non-Randomised Studies of Intervention (ROBINS-I) tool.

RESULTS

Of 11,209 studies screened, 59 non-randomised studies reporting outcomes on 331,157 patients were included. Patient characteristics regarding performance status and co-morbidity were recorded in 26 (44.1%) and 17 (28.8%) studies. The chemotherapy regime used was reported in 27 (45.8%) studies. The operative setting and the operative approach was reported in 42 (71%) and 14 (23.7%) studies. Post-operative mortality and morbidity were reported in 33 (55.9%) and 35 (59.3%) studies. Overall survival was reported in 49 (83.1%) studies, with 5 different definitions identified. Quality of life was only reported in 1 (1.7%) study.

CONCLUSION

This study demonstrates significant heterogeneity in the selection and definition of outcomes reported following PTR in mCRC. There is significant heterogeneity with a significant under-reporting of important outcomes such as treatment related adverse events and patient reported outcomes.

Survival outcomes following primary tumor resection for patients with incurable metastatic colorectal carcinoma: Experience from a single institution

OBJECTIVE

Palliative primary tumor resection (PTR) has been used for preventing and treating tumor-related complications. We aimed to determine whether PTR can increase overall survival (OS) in patients with unresectable metastatic colorectal cancer (CRC).

METHODS

A retrospective review of a prospectively collected database in a single center was performed. Patients diagnosed with metastatic CRC from January 2004 to December 2014 were included. Patients who had attained curative resection or had disease recurrence were excluded. All patients were discussed at a multidisciplinary tumor board where subsequent treatment decisions were made.

RESULTS

Altogether 408 patients were analyzed. Of these 145 received PTR with palliative chemotherapy (PC; group A), 110 received PC only (group B), 52 received PTR only (group C), while 101 received neither PTR nor PC (group D). Undergoing PTR led to statistically significant improvement in OS (22.7 months vs 12.1 months vs 6.9 months vs 2.7 months, P < 0.001). We performed subgroup analyses to control for potential confounders and found that the influence of PTR on OS persisted. With multivariate analysis, the predictors of poor OS were no PTR (hazards ratio [HR] 2.32, 95% confidence interval [CI] 1.82-2.96, P < 0.001), no PC (HR 4.25, 95% CI 3.27-5.33, P < 0.001) and the presence of peritoneal metastases (HR 1.37, 95% CI 1.06-1.78, P = 0.018). Diversion surgery did not lead to a statistical difference in OS.

CONCLUSIONS

The absences of PTR and PC, and peritoneal metastases are independently associated with decreased OS in patients with unresectable metastatic CRC. Randomized controlled trials are needed to verify this observation.

Kras-mutation influences outcomes for palliative primary tumor resection in advanced colorectal cancer-a Turkish Oncology Group study

PURPOSE

We aimed to investigate the prognostic effect of primary tumor resection (PTR) prior to bevacizumab-based treatments in unresectable metastatic colorectal cancer (mCRC).

METHODS

We retrospectively collected 341 mCRC cases with unresectable metastases at diagnosis. PTR was performed in 210 cases (the surgery group) and the other patients (n = 131) were followed without PTR (the no-surgery group). All the patients were treated with bevacizumab combined chemotherapy regimens.

RESULTS

The median progression free survival (PFS) of the surgery group was 10.4 months (95% CI: 8.9-11.9), which was significantly better than that of the no-surgery group (7.6 months, 95% CI: 6.4-8.8, P=0.000). The median overall survival (OS) of the surgery group was longer than that of the no-surgery group (27.4 months vs. 18.3 months, respectively, P=0.000). The median PFS and OS of the surgery group were 10.4 months and 28.2 months, which were significantly longer than that of the no-surgery group in Kras-mutant patients (7.8 months and 18.3 months; P=0.004, P=0.028, respectively). There was no difference in terms of PFS and OS between the surgery and the no-surgery groups in Kras-wild type patients.

CONCLUSION

Palliative PTR may improve the survival outcomes for unresectable mCRC patients. PTR may be preferred, particularly in Kras-mutant patients.

Modern-day palliative chemotherapy for metastatic colorectal cancer: does colonic resection affect survival?

BACKGROUND

Patients with metastatic colorectal cancer (mCRC) with surgically incurable metastases would be recommended for palliative chemotherapy (PC). The role of surgical intervention is debatable with no conclusive evidence for routine primary tumour resection (PTR) or stoma creation. We aimed to study if surgical intervention conferred a survival benefit in patients with mCRC who received upfront systemic therapy.

METHODS

A retrospective review of a prospectively collected database in a single centre was performed. Patients diagnosed with mCRC from January 2004 to December 2014 were included. We excluded patients who had an upfront surgical intervention, had no treatment with systemic therapy or had attained curative resection. The decision for surgery was based on the outcome of a multidisciplinary tumour board. Demographic, clinicopathological, treatment and follow-up data were collected. Univariate and multivariate analyses were performed.

RESULTS

Out of 408 patients with mCRC with incurable metastases, we analysed 124 patients who had upfront PC. Twenty-nine had PC + PTR (group A), 10 had PC + stoma (group B) and 85 had PC only (group C). Undergoing PTR led to significant improvement in overall survival (OS; 30.8 versus 13.4 versus 11.0 months, P < 0.001). With multivariate analysis, undergoing PTR and receiving biologics were independent good prognostic variables. Surgical resection was safe with minimal complications.

CONCLUSIONS

PTR was found to increase OS while stoma creation had no impact on OS. The benefits and safety of undergoing PTR may be a result of selection bias. Further prospective studies are required to confirm the observations of this study.

Primary tumor sidedness is an independent prognostic marker for survival in metastatic colorectal cancer: Results from a large retrospective cohort with mutational analysis

Recent reports demonstrate inferior outcomes associated with primary right‐sided vs left‐sided colorectal tumors in patients with metastatic colorectal cancer (mCRC). We sought to describe our experience with mCRC patients on whom we have molecular data to determine whether primary tumor sidedness was an independent prognostic marker for overall survival (OS). mCRC patients with documented primary tumor sidedness who received mutational profiling between 2009 and 2014 were identified (n = 367, median follow‐up 30.4 months). Mutational profiling for >150 mutations across commonly mutated cancer genes including RAS, PIK3CA, BRAF, and PTEN as well as treatment data, including receipt of a biologic agent, were collected. Univariable/multivariable models were used to analyze relationships between collected data and OS. Among 367 patients, sidedness breakdown was as follows: 234 left (64%), 133 right (36%). 56% were male, with a median age at diagnosis of 57 (range 24‐89). A total of 143 patients had RAS mutations. Five‐year OS was 41%, median OS was 54 months (range 1‐149). Five‐year OS for left‐ vs right‐sided tumors was 46% vs 24% (P < .0001). On univariable analysis, among both RAS wildtype and mutant tumors, left‐sided tumors continued to have improved OS vs right‐sided tumors (HR: 0.49, 95% CI: 0.34‐0.69 RAS wildtype; HR: 0.61, 95% CI: 0.40‐0.95 RAS mutant). Left‐sidedness was an important prognostic factor for OS among RAS wildtype patients despite treatment with or without a biologic agent (P < .05). Left‐sidedness remained significant for improved OS on multivariable analysis (P < .0001). Left‐sided primary tumor remained most important prognostic factor for OS, even when adjusting for mutational status and receipt of biologic agent.

Benefit of Surgical Resection of the Primary Tumor in Patients Undergoing Chemotherapy for Stage IV Colorectal Cancer with Unresected Metastasis

PURPOSE

Resection of the primary tumor in patients with unresected metastatic colorectal cancer is controversial, and often performed only for palliation of symptoms. Our goal was to determine if resection of the primary tumor in this patient population is associated with improved survival.

METHODS

This is a retrospective cohort study of the National Cancer Data Base from 2004 to 2012. The study population included all patients with synchronous metastatic colorectal adenocarcinoma who were treated with systemic chemotherapy. The study groups were patients who underwent definitive surgery for the primary tumor and those who did not. Patients were excluded if they had surgical intervention on the sites of metastasis or pathology other than adenocarcinoma. Primary outcome was overall survival.

RESULTS

Of the 65,543 patients with unresected stage IV colorectal adenocarcinoma undergoing chemotherapy, 55% underwent surgical resection of the primary site. Patients who underwent surgical resection of the primary tumor had improved median survival compared to patients treated with chemotherapy alone (22 vs 13 months, p < .0001). The surgical survival benefit was present for patients who were treated with either multi-agent or single-agent chemotherapy (23 vs 14 months, p < 0.001; 19 vs 9 months, p < 0.001). Surgical resection of the primary tumor was also associated with improved survival when using multivariate analysis with propensity score matching (OR = 0.863; 95% CI [0.805-.924]; HR = 0.914; 95% CI [0.888-0.942]).

CONCLUSIONS

Our results show that in patients with synchronous unresected stage IV colorectal adenocarcinoma undergoing single- or multi-agent chemotherapy, after adjusting for confounding variables, definitive resection of the primary site was associated with improved overall survival. Large randomized controlled trials are needed to determine if there is a causal relationship between surgery and increased overall survival in this patient population.

Prognostic value of primary tumour resection in synchronous metastatic colorectal cancer: Individual patient data analysis of first-line randomised trials from the ARCAD database

Indication for primary tumour resection (PTR) in asymptomatic metastatic colorectal cancer (mCRC) patients is unclear. Previous retrospective analyses suggest a survival benefit for patients who underwent PTR. The aim was to evaluate the prognostic value of PTR in patients with synchronous mCRC by analysis of recent large RCTs including systemic therapy with modern targeted agents. Individual patient data (IPD) of 3423 patients enrolled into 8 randomised controlled trials (RCTs) with first-line systemic therapy in the ARCAD (Aide et Recherche en Cancérologie Digestive) database were analysed. The number of patients with unresected synchronous mCRC, resected synchronous mCRC and metachronous mCRC was 710 (21%), 1705 (50%) and 1008 (29%), respectively. Adjusting for age, gender, performance status (PS) and prior chemotherapy, the unresected group had a significantly worse median overall survival (16.4 m) compared with the synchronous resected (22.2 m; hazard ratio [HR] 1.60, 95% CI 1.43-1.78) and metachronous (22.4 m; HR 1.81, 95% CI 1.58-2.07) groups. Similarly, median progression-free survival was significantly worse for the unresected group compared with the synchronous resected (HR 1.31, 95% CI 1.19-1.44) and metachronous (HR 1.47, 95% CI 1.30-1.66) groups. In a multivariate analysis, the observed associations remained significant. This largest IPD analysis of mCRC trials to date demonstrates an improved survival in synchronous mCRC patients after PTR. These results may be subject to bias since reasons for (non)resection were not available. Until results of ongoing RCTs are available, both upfront PTR followed by systemic treatment and upfront systemic treatment are considered appropriate treatment strategies.

Meta-analysis of outcomes following resection of the primary tumour in patients presenting with metastatic colorectal cancer

BACKGROUND

It is not clear whether resection of the primary tumour (when there are metastases) alters survival and/or whether resection is associated with increased morbidity. This systematic review and meta-analysis assessed the prognostic value of primary tumour resection in patients presenting with metastatic colorectal cancer.

METHODS

A systematic review of MEDLINE/PubMed was performed on 12 March 2016, with no language or date restrictions, for studies comparing primary tumour resection versus conservative treatment without primary tumour resection for metastatic colorectal cancer. The quality of the studies was assessed using the MINORS and STROBE criteria. Differences in survival, morbidity and mortality between groups were estimated using random-effects meta-analysis.

RESULTS

Of 37 412 initially screened articles, 56 retrospective studies with 148 151 patients met the inclusion criteria. Primary tumour resection led to an improvement in overall survival of 7·76 (95 per cent c.i. 5·96 to 9·56) months (risk ratio (RR) for overall survival 0·50, 95 per cent c.i. 0·47 to 0·53), but did not significantly reduce the risk of obstruction (RR 0·50, 95 per cent c.i. 0·16 to 1·53) or bleeding (RR 1·19, 0·48 to 2·97). Neither was the morbidity risk altered (RR 1·14, 0·77 to 1·68). Heterogeneity between the studies was high, with a calculated I² of more than 50 per cent for most outcomes.

CONCLUSION

Primary tumour resection may provide a modest survival advantage in patients presenting with metastatic colorectal cancer.

Randomized Clinical Trials in Colon and Rectal Cancer

Surgery remains the mainstay of treatment for colon and rectal cancers. Colon cancer outcomes have improved with laparoscopic techniques, enhanced recovery pathways, and adjuvant chemotherapy. Adjuvant 5-fluorouracil with or without oxaliplatin in stage III and possibly high-risk stage II colon cancer is associated with improved survival. Multimodality management of rectal cancer continues to evolve; total mesorectal excision is the cornerstone. Oncologic results do not support the use of laparoscopic resection in rectal cancer. Preoperative short- or long-course radiation for stage II or III rectal cancer is the standard of care. Long course chemoradiation is recommended for bulky tumors.

Primary tumor location as a predictor of the benefit of palliative resection for colorectal cancer with unresectable metastasis

Background

It is still under debate that whether stage IV colorectal cancer patients with unresectable metastasis can benefit from primary tumor resection, especially for asymptomatic colorectal cancer patients. Retrospective studies have shown controversial results concerning the benefit from surgery. This retrospective study aims to evaluate whether the site of primary tumor is a predictor of palliative resection in asymptomatic stage IV colorectal cancer patients.

Methods

One hundred ninety-four patients with unresectable metastatic colorectal cancer were selected from Sun Yat-sen University Cancer Center Database in the period between January 2007 and December 2013. All information was carefully reviewed and collected, including the treatment, age, sex, carcinoembryonic antigen, site of tumor, histology, cancer antigen 199, number of liver metastases, and largest diameter of liver metastasis. The univariate and multivariate analyses were used to detect the relationship between primary tumor resection and overall survival of unresectable stage IV colorectal cancer patients.

Results

One hundred twenty-five received palliative resection, and 69 received only chemotherapy. Multivariate analysis indicated that primary tumor site was one of the independent factors (RR 0.569, P = 0.007) that influenced overall survival. For left-side colon cancer patients, primary tumor resection prolonged the median overall survival time for 8 months (palliative resection vs. no palliative resection: 22 vs. 14 months, P = 0.009); however, for right-side colon cancer patients, palliative resection showed no benefit (12 vs. 10 months, P = 0.910).

Conclusions

This study showed that left-side colon cancer patients might benefit from the primary tumor resection in terms of overall survival. This result should be further explored in a prospective study.

Update on optimal treatment for metastatic colorectal cancer from the ACTG/AGITG expert meeting: ECCO 2015

The treatment of metastatic CRC (mCRC) has evolved over the last 20 years, from fluoropyrimidines alone to combination chemotherapy and new biologic agents. Median overall survival is now over 24 months for RAS mutated (MT) patients and over 30 months for RAS wild-type (WT) patients. However, there are subgroups of patients with BRAF V600E MT CRC who have a significantly poorer outlook. Newer treatment options are also being explored in select subgroups of patients (anti-HER 2 in HER2 positive mCRC and immunotherapy in patients with defective mismatch repair (dMMR)). The best use of these systemic treatment options, as well as surgery in well-selected patients requires careful consideration of predictive biomarkers and importantly, the optimal sequence in which therapies should be given to derive maximal benefit. A group of colorectal subspecialty medical oncologists from Australia, USA, The Netherlands and Germany met during ECCO 2015 in Vienna to review current practice.