How Uncommon are Isolated Lung Metastases in Colorectal Cancer? A Review from Database of 754 Patients Over 4 Years

• Published in: Journal of gastrointestinal surgery Vol. 13; no. 4; pp. 642 - 648
• Main Authors: Tan, Ker Kan, Lopes Jr, Gilberto de Lima, Sim, Richard
• Format: Journal Article
• Language: English
• Published: New York Springer-Verlag 01.04.2009; Springer Nature B.V
• Subjects: Adult; Aged; Aged, 80 and over; Colon; Colonic Neoplasms - drug therapy; Colonic Neoplasms - pathology; Colonic Neoplasms - surgery; Colorectal cancer; Female; Gastroenterology; Humans; Incidence; Liver Neoplasms - secondary; Lung Neoplasms - epidemiology; Lung Neoplasms - secondary; Male; Medical imaging; Medicine; Medicine & Public Health; Middle Aged; Neoplasm Staging; Original Article; Rectal Neoplasms - drug therapy; Rectal Neoplasms - pathology; Rectal Neoplasms - surgery; Retrospective Studies; Surgery; Young Adult; Lung metastases; Skipped metastases; Isolated; Colorectal cancer
• ISSN: 1091-255X; 1873-4626
• DOI: 10.1007/s11605-008-0757-7

Background It is commonly thought that colon cancer metastases to the lungs without involvement of the liver are rare. Methods We performed a retrospective review of all patients with colorectal cancer diagnosed between December 2003 and August 2007 in Singapore. Isolated lung metastases were determined as (1) Definite if there was confirmed histology or cytology of the lung lesion(s) in the absence of liver lesions on CT scan, and (2) Probable if there were only radiological evidence suggestive of lung metastases rather than lung primary also in the absence of liver lesions on CT scan. Results There were 196 patients with rectal and 558 patients with colon cancer (369 left-sided and 189 right-sided). There were 13 definite isolated lung metastases, and the remaining 43 were probable. Twenty-three (12%) patients with rectal cancer and 33 (6%) patients with colon cancer had isolated lung metastases (OR 2.11, 95% CI 1.21–3.70). Patients with ≥pT3 lesions (OR 1.92, 95% CI 0.75–4.93) and ≥pN1 (OR 1.56, 95% CI 0.86– 2.83) were more likely to have isolated lung metastases. Conclusion The true incidence of isolated lung without liver metastases in colorectal cancer is likely to lie between 1.7% and 7.2%. While the incidence of isolated lung metastases is twice as common in patients with rectal cancer, it is still significant in patients with colon cancer. The absence of liver involvement should not preclude a search for lung metastases.