Analysis of factors affecting survival in patients with lung metastases from colorectal cancer who underwent video-assisted thoracoscopic (VAT) surgical resection

Background: Colorectal cancer (CRC) is one of the most common malignancy in both sexes, and the onset of liver or lung metastases (LMs) significantly affects overall survival (OS) of patients. The main reported prognostic factors related to OS are the age, preoperative carcinoembryonic antigen (CEA) serum levels, lymph node involvement, neoadjuvant chemotherapy, disease-free survival, and number and size of LMs. We have previously reported that the primary tumor site should not be considered a major criterion in selecting patients for pulmonary metastasectomy (Anticancer Res 36: 13-22, 2016). The aim of this retrospective study was to analyze whether the age of the patients and the number and size of LMs could affect survival of patients who underwent curative surgery for CRC and developed metachronous LMs during follow-up. Patients and methods: We reviewed the medical reports of 36 patients who underwent video-assisted thoracoscopic (VAT) lung metastasectomy for LMs from CRC. There were 21 (58.3%) men (57.9±14.9 years) and 15 (41.7%) women (63.3±11.1 years). Because the data were not normally distributed, the Mann-Whitney U-test was used to evaluate the differences between groups. The Pearson correlation coefficient (r) and the linear regression equation calculation was obtained to evaluate the relationship between survival and the main risk factors, including age of the patients, size and number of the LMs. A p-value <0.05 was considered statistically significant. Results: The age between men and women did not differ significantly (Z=0.35, p=0.71). The overall survival was 30.6±25.1 months (median 24.5 months, range 1-92 months). The mean number of the excised LMs was 2.1±1.6 (median 1.5, range 1-9) and the mean size of the greatest LM was 17±8 mm (median 15 mm, range 5-32 mm). No correlation was found between survival and age (r=0.099, p=0.56), mean size of LM (r=-0.209, p=0.22) or number of the LMs (r=-0.196, p=0.25). The Table reports the relative regression line equation. Conclusion: In patients with LMs from CRC, the OS is independent of the number and size of LM and the age of the patients. Further studies will eventually confirm our results.