Survival and prognostic factors of isolated pulmonary metastases originating from colorectal cancer: An 8-year single-center experience

Ameera S Balhareth; Abdullah S AlQattan; Hassan M Alshaqaq; Abdullah M Alkhalifa; Alaa A Al Abdrabalnabi; Muna S Alnamlah; Deborah MacNamara

doi:10.1016/j.amsu.2022.103559

Survival and prognostic factors of isolated pulmonary metastases originating from colorectal cancer: An 8-year single-center experience

Ann Med Surg (Lond). 2022 Apr 4:77:103559. doi: 10.1016/j.amsu.2022.103559. eCollection 2022 May.

Authors

Ameera S Balhareth¹, Abdullah S AlQattan², Hassan M Alshaqaq³, Abdullah M Alkhalifa⁴, Alaa A Al Abdrabalnabi³, Muna S Alnamlah³, Deborah MacNamara⁵

Affiliations

¹ Colorectal Section, Department of Surgery, King Fahad Specialist Hospital, Dammam, Saudi Arabia.
² Department of Surgery, King Fahad Specialist Hospital, Dammam, Saudi Arabia.
³ College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia.
⁴ Department of General Surgery, King Fahad University Hospital, Khobar, Saudi Arabia.
⁵ Department of Colorectal Surgery Beaumont Hospital and National Clinical Programme in Surgery, RCSI, Ireland.

Abstract

Background: Isolated pulmonary metastasis (IPM) is a rare entity that accounts for 10% of pulmonary metastases seen in colorectal cancer (CRC). This study aims to evaluate the overall 5-year survival of IPM originating from CRC and identify potential prognostic factors affecting the overall survival (OS).

Methods: A retrospective cohort study conducted in a tertiary care center. The study included all patients diagnosed with CRC aged 18-75 years who underwent primary tumor resection with curative intent between 2008 and 2015, and developed IPM. Patients with no follow-up and those with extra-pulmonary metastases were excluded.

Results: The prevalence of IPM in the overall CRC cases was 4.18% (20/478 patients). The mean age of patients with IPM was 52.7 ± 12.9 years. Ten patients had synchronous IPM (50%), thirteen had unilateral (65%), and eleven underwent metastasectomy (55%). The 5-year OS was 40%, and the mean OS was 3.12 ± 1.85 years. Several factors were found to be associated with a favorable outcome, which include unilateral IPM (3.69 vs. 2.07 years; P = 0.024), metachronous (4.25 vs. 2.14 years; P = 0.017), metastasectomy (4.81 vs. 1.83 years; P = 0.005). In addition, mortality was likely to be decreased by more than 90% after metastasectomy (unadjusted odds ratio = 0.071; 95% confidence interval [CI] = 0.01-0.8; P = 0.032).

Conclusions: Forty percent of the included patients survived the 5-year follow-up. Better survival was associated with the metastases being unilateral, metachronous, and metastasectomy. Mortality was lower in patients with pulmonary recurrence after metastasectomy.

Keywords: CI, Confidence interval; CRC, Colorectal cancer; CT, Computed tomography; Colorectal cancer; DFI-1, Disease-free interval 1; DFI-2, Disease-free interval 2; IPM, Isolated pulmonary metastasis; IQR, Interquartile range; Isolated pulmonary metastasis; OS, Overall survival; Prognosis; Pulmonary metastasectomy; SD, Standard deviation; Survival; UOR, Unadjusted odds ratio.