The fact that socially disadvantaged cancer patients face a greater risk of mortality than the advantaged is well recognized but poorly understood. Existing research and a newly completed 10-year survival study suggest that complex interrelations among biological factors, medical interventions, and specific dimensions of social differentiation determine survival differences. Patterns of interrelations among determinants of survival appear compatible with an "economic" model in some forms of cancer and a "cognitive-behavioral" model in others. Findings presented here suggest that improved access to health care will reduce mortality risk among the disadvantaged in at least some malignancies, but will not alone make their survival chances equal to those of the advantaged.