Improving treatment and survival: a population-based study of current outcomes after a hepatic resection in patients with metastatic colorectal cancer.
BACKGROUND
Population-based studies historically report underutilization of a resection in patients with colorectal metastases to the liver. Recent data suggest limitations of the methods in the historical analysis. The present study examines trends in a hepatic resection and survival among Medicare recipients with hepatic metastases.


METHODS
Medicare recipients with incident colorectal cancer diagnosed between 1991 and 2009 were identified in the SEER(Surveillance, Epidemiology and End Results)-Medicare dataset. Patients were stratified into historical (1991-2001) and current (2002-2009) cohorts. Analyses compared treatment, peri-operative outcomes and survival.


RESULTS
Of 31.574 patients with metastatic colorectal cancer to the liver, 14,859 were in the current cohort treated after 2002 and 16,715 comprised the historical control group. The overall proportion treated with a hepatic resection increased significantly during the study period (P < 0.001) with pre/post change from 6.5% pre-2002 to 7.5% currently (P < 0.001). Over time, haemorrhagic and infectious complications declined (both P ≤ 0.047), but 30-day mortality was similar (3.5% versus 3.9%, P = 0.660). After adjusting for predictors of survival, the use of a hepatic resection [hazard ratio (HR) = 0.40, 95% confidence interval (CI): 0.38-0.42, P < 0.001] and treatment after 2002 (HR = 0.88, 95% CI: 0.86-0.90, P < 0.001) were associated with a reduced risk of death.


CONCLUSIONS
Case identification using International Classification of Diseases, 9th Revision (ICD-9) codes is imperfect; however, comparison of trends over time suggests an improvement in multimodality therapy and survival in patients with colorectal metastases to the liver.
Section of Hepatobiliary and Pancreatic Surgery, Department of Surgery, University of Virginia, Charlottesville, VA, USA.|Surgical Outcomes Research Center, University of Virginia, Charlottesville, VA, USA.
Victor M
VM
Zaydfudim
Surgical Outcomes Research Center, University of Virginia, Charlottesville, VA, USA.|Department of Public Health Sciences, University of Virginia, Charlottesville, VA, USA.
Timothy L
TL
McMurry
Surgical Outcomes Research Center, University of Virginia, Charlottesville, VA, USA.|Section of Colorectal Surgery, Department of Surgery, University of Virginia, Charlottesville, VA, USA.
Amy M
AM
Harrigan
Section of Colorectal Surgery, Department of Surgery, University of Virginia, Charlottesville, VA, USA.
Charles M
CM
Friel
Surgical Outcomes Research Center, University of Virginia, Charlottesville, VA, USA.|Department of Public Health Sciences, University of Virginia, Charlottesville, VA, USA.
George J
GJ
Stukenborg
Section of Hepatobiliary and Pancreatic Surgery, Department of Surgery, University of Virginia, Charlottesville, VA, USA.
Todd W
TW
Bauer
Section of Hepatobiliary and Pancreatic Surgery, Department of Surgery, University of Virginia, Charlottesville, VA, USA.
Reid B
RB
Adams
Surgical Outcomes Research Center, University of Virginia, Charlottesville, VA, USA.|Section of Colorectal Surgery, Department of Surgery, University of Virginia, Charlottesville, VA, USA.
Traci L
TL
Hedrick
D000230:Adenocarcinoma / Q000175:diagnosis / Q000556:secondary* / Q000601:surgery; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D015994:Incidence; D008113:Liver Neoplasms / Q000175:diagnosis / Q000556:secondary* / Q000601:surgery; D008297:Male; D009367:Neoplasm Staging; D011184:Postoperative Period; D012189:Retrospective Studies; D018426:SEER Program; D015996:Survival Rate / Q000639:trends; D014768:Virginia / Q000453:epidemiology