Disparities in cancer diagnosis and survival

Concern has been raised over the disproportionate cancer mortality among minority and low-income persons. The current study examined differences in disease stage at the time of diagnosis and subsequent survival for patients who are medically indigent compared with the rest of the population of cancer patients in Michigan.

The authors linked three Michigan statewide data bases: the Cancer Registry, Medicaid enrollment files, and death certificates. The analysis focused on female breast, cervix, lung, prostate, and colon carcinoma, and differences were analyzed in the incidence, disease stage at the time of diagnosis, and survival between younger women and older women who were either insured or not insured by Medicaid. To estimate the risk of late stage diagnosis and death, the authors used logistic regression, controlling for age, race, and Medicaid enrollment. Ordered logit models also were used as a refinement of disease stage prediction.

Medically indigent persons had a disproportionately larger share of cancer. Persons age < 65 years who were insured by Medicaid had the greatest risk of late stage diagnosis and death across all five disease sites analyzed. African-American women had a greater risk of death from breast carcinoma compared with other women independent of Medicaid status. No interaction effects were found between age, race, and/or gender and Medicaid enrollment.

The results of this study showed that the disparities in cancer outcomes may be greater than previously thought and are consistent across disease sites. If advancements made in cancer control are to be shared by the low-income population, then improvements clearly are needed in cancer prevention, early detection, and treatment for the poor.