Clinical outcome of up-front surgery in patients with asymptomatic, incurable synchronous peritoneal carcinomatosis

Primary tumor resection for asymptomatic colorectal cancer patients with synchronous unresectable metastases: a meta-analysis of randomized controlled trials and case-matched studies

PURPOSE

The value of upfront primary tumor resection (PTR) for asymptomatic unresectable metastatic colorectal cancer (mCRC) patients remains contentious. This meta-analysis aimed to assess the prognostic significance of upfront PTR for asymptomatic unresectable mCRC.

METHODS

A systematic literature search was performed on June 21st, 2024. To minimize the bias and ensure robust evidence, only randomized controlled trials (RCTs) and case-matched studies (CMS) that compared PTR followed by chemotherapy to chemotherapy alone were included. The primary outcome was overall survival (OS), while cancer-specific survival (CSS) served as the secondary outcome.

RESULTS

Eight studies (three RCTs and five CMS) involving 1221 patients were included. Compared to chemotherapy alone, upfront PTR followed by chemotherapy did not improve OS (hazard ratios [HR] 0.91, 95% confidence interval [CI] 0.79-1.04, P = 0.17), but was associated with slightly better CSS (HR 0.59, 95% CI 0.40-0.88, P = 0.009).

CONCLUSIONS

The current limited evidence indicates that upfront PTR does not improve OS but may enhance CSS in asymptomatic unresectable mCRC patients. Ongoing trials are expected to provide more reliable evidence on this issue.

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.

Management of asymptomatic primary tumours in stage IV colorectal cancer: Review of outcomes

AIM: To compare outcomes for patients presenting with stage IV colorectal cancer and an asymptomatic primary tumour, undergoing primary tumour resection (PTR) plus palliative chemotherapy vs primary chemotherapy up-front.

METHODS: A literature search was conducted using MEDLINE and EMBASE. The primary outcome was overall survival. Secondary outcomes included perioperative mortality, morbidity and delayed surgical intervention rates in patients undergoing PTR and subsequent complication rates in patients with an un-resected primary tumour. Tertiary outcomes included impact on systemic treatment and identification of prognostic factors relevant for survival in this cohort.

RESULTS: Twenty non-randomised studies met the inclusion criteria. Eleven studies included comparative overall survival data. Three studies showed an overall survival advantage for PTR, 7 studies showed no statistically significant advantage, and 1 study showed a significant worsening in survival in the surgical group. The perioperative mortality rate ranged from 0% to 8.5%, and post-operative morbidity rate from 10% to 35%, mainly minor complications that did not preclude subsequent chemotherapy. The rate of delayed primary-tumour related symptoms, most commonly obstruction, in patients with an un-resected primary tumour ranged from 3% to 46%. The strongest independent poor prognostic factor was extensive hepatic metastases, in addition to poor performance status, M1b stage and non-use of modern chemotherapy agents.

CONCLUSION: Based on the current literature, both PTR and up front chemotherapy appear appropriate initial management strategies, with a trend towards an overall survival advantage with PTR. The procedure has a low post-operative mortality, and most complications are transient and minor. The results of recruiting randomised trials are eagerly anticipated.