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.

Complications from the primary tumour are not related with survival in patients with synchronous stage IV colorectal cancer receiving chemotherapy without primary tumour resection

BACKGROUND

The aim of this study was to evaluate the rate of complications from the primary tumour (CPT) requiring surgical or endoscopic intervention during chemotherapy treatment in patients with incurable synchronous stage IV colorectal cancer, the possibility of predicting such complications and their influence on survival.

METHODS

One hundred and twenty-five patients were initially treated with chemotherapy. Patients were grouped on the basis of appearance or not of CPT. We assessed the relation between age, gender, carcinoembryonic antigen (CEA) level, primary tumour location, alkaline phosphatase level, unilobar or bilobar liver involvement, presence of peritoneal carcinomatosis, the number of sites of metastatic disease, the addition of target therapies to chemotherapy, the ability to traverse the tumour with an endoscope and the appearance of complications due to the primary tumour and overall survival.

RESULTS

Mean age was 64.9 years, and 89 patients were men. Over a mean of 234 days, 25 patients (20 %) developed a CPT. Eighteen patients required surgery, and seven were treated exclusively by an endoscopic procedure. Mean survival was 15.8 months. We found a statistically relevant correlation between the inability to traverse the tumour with an endoscope and the occurrence of a CPT. There was no statistical differences in survival between both groups, but patients receiving target therapies had better survival.

CONCLUSION

Twenty percent of patients will suffer a CPT during chemotherapy treatment. The inability to pass the tumour with an endoscope can predict the CPT. Survival was only related to the addition of target therapies to chemotherapy.