Does colon cancer ever metastasize to bone first? a temporal analysis of colorectal cancer progression

TLDR

Colorectal cancer rarely metastasizes to bone. The study aimed to determine whether colorectal cancer can bypass other organs and metastasize directly to bone, and whether lung lesions better predict bone metastasis timing than liver lesions. A retrospective analysis of 252 colon cancer patients using whole‑body 18F‑FDG PET/CT and CT, combined with clinical history and other imaging, was performed to assess disease progression. No patient had isolated bone metastasis, bone metastasis occurred later than liver metastasis (21.2 vs 9.8 months), and lung metastasis was a stronger predictor of subsequent bone involvement than liver metastasis.

Abstract

Abstract Background It is well recognized that colorectal cancer does not frequently metastasize to bone. The aim of this retrospective study was to establish whether colorectal cancer ever bypasses other organs and metastasizes directly to bone and whether the presence of lung lesions is superior to liver as a better predictor of the likelihood and timing of bone metastasis. Methods We performed a retrospective analysis on patients with a clinical diagnosis of colon cancer referred for staging using whole-body 18 F-FDG PET and CT or PET/CT. We combined PET and CT reports from 252 individuals with information concerning patient history, other imaging modalities, and treatments to analyze disease progression. Results No patient had isolated osseous metastasis at the time of diagnosis, and none developed isolated bone metastasis without other organ involvement during our survey period. It took significantly longer for colorectal cancer patients to develop metastasis to the lungs (23.3 months) or to bone (21.2 months) than to the liver (9.8 months). Conclusion: Metastasis only to bone without other organ involvement in colorectal cancer patients is extremely rare, perhaps more rare than we previously thought. Our findings suggest that resistant metastasis to the lungs predicts potential disease progression to bone in the colorectal cancer population better than liver metastasis does.