Metastatic spread pattern after curative colorectal cancer surgery. A retrospective, longitudinal analysis.
OBJECTIVE
The most common sites of colorectal cancer (CRC) recurrence are the local tissues, liver or lungs. The objective was to identify risk factors associated with the primary CRC tumor and cancer recurrence in these anatomical sites.


METHODS
Retrospective, longitudinal analyses of data on CRC survivors. Multivariable Cox regression analysis was performed to examine the association between possible cofounders with recurrence to various anatomical sites.


RESULTS
Data for 10,398CRC survivors (tumor location right colon=3870, left colon=2898, high rectum=2569, low rectum=1061) were analyzed; follow up time was up to five years. Mean age at curative surgery was 71.5 (SD 11.8) years, 20.2% received radio-chemotherapy, stage T3 (64.4%) and N0 (65.1%) were most common. Overall 1632 (15.7%) had cancer recurrence (Isolated liver n=412, 3,8%;  isolated lung n=252, 2,4%; isolated local n=223, 2.1%). Risk factors associated with recurrent CRC were identified, i.e. isolated liver metastases (male: Adjusted Hazard Ratio (AHR) 1,45; colon left: AHR 1,63; N2 disease: AHR 3,35; T2 disease: AHR 2,82), isolated lung metastases (colon left: AHR 1,53; rectum high: AHR 2,48; rectum low: AHR 2,65; N2 disease 3,76), and local recurrence (glands examined<12: AHR 1,51; CRM <3mm: AHR 1,60; rectum high: AHR 2,15; N2 disease: AHR 2,58) (all p values <0001).


CONCLUSIONS
Our study finds that the site of the primary CRC tumor is associated with location of subsequent metastasis. Left sided colon cancers have increased risk of metastatic spread to the liver, whereas rectal cancers have increased risk of local recurrence and metastatic spread to the lungs. These results, in combination with other risk factors for CRC recurrence, should be taken into consideration when designing risk adapted post-treatment CRC surveillance programs.
Department of Colorectal Surgery, University Hospitals Case Medical Center, Cleveland, Ohio, USA; Department of Surgery, Hammerfest Hospital, Hammerfest, Norway; Norwegian National Centre of Integrated Care and Telemedicine, University Hospital North Norway, Tromsø, Norway. Electronic address: knut.magne.augestad@telemed.no.
K M
KM
Augestad
Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, USA; Population Health and Outcomes Research Core, Clinical and Translational Science Collaborative, Cleveland, Ohio, USA.
P M
PM
Bakaki
Case Western Reserve University, Department of Family Medicine and Community Health, Cleveland, Ohio, USA; Case Comprehensive Cancer Center, Cleveland, Ohio, USA.
J
J
Rose
Department of Colorectal Surgery, University Hospitals Case Medical Center, Cleveland, Ohio, USA.
B P
BP
Crawshaw
Department of Gastrointestinal Surgery, University Hospital North Norway, Tromsø, Norway.
R O
RO
Lindsetmo
The Norwegian Cancer Registry, Oslo, Norway.
L M
LM
Dørum
Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, USA; Population Health and Outcomes Research Core, Clinical and Translational Science Collaborative, Cleveland, Ohio, USA.
S M
SM
Koroukian
Department of Colorectal Surgery, University Hospitals Case Medical Center, Cleveland, Ohio, USA.
C P
CP
Delaney
D000368:Aged; D015179:Colorectal Neoplasms / Q000473:pathology*; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary*; D008137:Longitudinal Studies; D008175:Lung Neoplasms / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors