Comparative Effectiveness Research: The Impact of Biologic Agents in Ethnic Minorities With Metastatic Colorectal Cancer.
BACKGROUND
Biologic agents have improved the outcomes of patients with metastatic colorectal cancer (mCRC). However, the clinical trials included a predominately white population (85%), with Hispanic and black patients underrepresented. Thus, the real world benefit for the latter remains unknown. Comparative effectiveness research is a tool allowing for this exploration.


PATIENTS AND METHODS
The demographic and clinical characteristics of patients treated for mCRC from 2000 to 2011 were extracted from the medical records of Montefiore Medical Center. A semiparametric accelerated failure time model was used to assess the survival differences between patients receiving chemotherapy (CT) alone versus CT plus biologic agents (CBT).


RESULTS
Of the 290 patients (black, 45.9%; Hispanic, 26.2%; and white, 27.9%), 53.8% received biologic agents. The median overall survival was 15.2 months in the CT-alone group and 25.6 months in CBT group (P = .004). On univariate analysis, a lower number of metastatic sites, carcinoembryonic antigen < 41 ng/mL, and more lines of CT were associated with improved overall survival. In a propensity score-based analysis of the entire cohort, CBT offered a survival benefit compared with CT alone (increased median survival, 1.44-fold; 95% confidence interval [CI], 1.11-1.86; P = .038). The results of the subgroup analysis suggested a survival benefit for white patients (2.01; 95% CI, 1.26-3.23; P = .031) but not for Hispanic (1.42; 95% CI, 0.91-2.20; P = .370) or black (1.12; 95% CI, 0.76-1.66; P = .596) patients.


CONCLUSION
In the present cohort, CBT was associated with longer survival, with the effect mainly driven by the outcomes for white patients, with black patients not appearing to benefit. These data are provocative and warrant further confirmation. Efforts to increase ethnic minority patients' enrollment in clinical trials is required to prospectively define the benefit from novel therapies.
['Goel|Sanjay|S|', 'Negassa|Abdissa|A|', 'Khot|Ashish|A|', 'Goyal|Dharmendra|D|', 'Guo|Shuang|S|', 'Nandikolla|Amara|A|', 'Bakirhan|Kamila|K|', 'Polineni|Rahul|R|', 'Shah|Umang|U|', 'Chaudhary|Imran|I|', 'Ghalib|Mohammad H|MH|', 'Rajdev|Lakshmi|L|', 'Kaubisch|Andreas|A|', 'Chuy|Jennifer|J|', 'Aparo|Santiago|S|']
D000328:Adult D001741:African Americans D000368:Aged D000369:Aged, 80 and over D000971:Antineoplastic Combined Chemotherapy Protocols D001685:Biological Factors D002272:Carcinoembryonic Antigen D015331:Cohort Studies D015179:Colorectal Neoplasms D057186:Comparative Effectiveness Research D005260:Female D006630:Hispanic or Latino D006801:Humans D008297:Male D008875:Middle Aged D008962:Models, Theoretical D015996:Survival Rate D016896:Treatment Outcome D044465:Whites
Comparative effectiveness research Colorectal cancer Chemotherapy Biologic therapy Race