Does colon cancer ever metastasize to bone first? a temporal analysis of colorectal cancer progression.
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 18F-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).


CONCLUSIONS
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.
Roth
Eira S
ES
The University of Texas Medical School, Houston, Texas 77030, USA. eira.roth@gmail.com
Fetzer
David T
DT
Barron
Bruce J
BJ
Joseph
Usha A
UA
Gayed
Isis W
IW
Wan
David Q
DQ
D000368:Aged; D001859:Bone Neoplasms / Q000556:secondary*; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary; D008175:Lung Neoplasms / Q000556:secondary; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D049268:Positron-Emission Tomography; D011859:Radiography; D012189:Retrospective Studies; D051598:Whole Body Imaging