Exploratory Analysis on Overall Survival after Either Surgery or Stereotactic Radiotherapy for Lung Oligometastases...

Area of Science:

• Oncology
• Radiation Oncology
• Surgical Oncology

Background:

• Stage IV colorectal cancer (CRC) with limited lung metastases (oligometastases) is often treated with lung metastasectomy or stereotactic body radiotherapy (SBRT).
• A direct comparison between SBRT and surgery for these patients is lacking.
• Retrospective studies are crucial for exploring treatment efficacy when randomized trials are unavailable.

Purpose of the Study:

• To retrospectively compare the overall survival (OS) and progression-free survival (PFS) of patients with stage IV CRC and lung oligometastases treated with SBRT versus lung metastasectomy.
• To evaluate the effectiveness of SBRT as a local therapy for lung oligometastases in CRC patients.

Main Methods:

• A comparative cohort study included 142 patients treated with surgery and 28 patients treated with SBRT between 2005 and 2012.
• Overall survival and PFS were analyzed using Kaplan-Meier curves and compared with the Log-rank test.
• Cox proportional hazards models and inverse probability of treatment weighting (IPTW) were used for multivariable analysis.

Main Results:

• Patients receiving SBRT were older and treated more recently; baseline characteristics were otherwise similar.
• Two-year overall survival rates were 77% for SBRT and 82% for surgery (P=0.134).
• Multivariable analyses did not show a significant difference in overall survival between SBRT and surgery (adjusted HR=1.71, P=0.149 with Cox models; HR=1.28, P=0.547 with IPTW).
• Progression-free survival results were deemed unreliable due to differing follow-up protocols.

Conclusions:

• This explorative analysis suggests that SBRT offers similar overall survival to surgery for the first two years in stage IV CRC patients with lung oligometastases.
• The retrospective design and sample size limitations necessitate cautious interpretation of the findings.
• High-quality comparative trials are essential to definitively determine the optimal treatment modality for lung oligometastases in CRC.