Decreased incidence of cervical cancer in medicare-eligible California women.

Objective: To determine if the incidence of invasive cervical cancer relative to carcinoma in situ decreased in Medicare-eligible women.

Methods: A retrospective cohort was amassed from the California Cancer Registry database. The hypothesis was prospectively specified. Mean ratio of invasive (International Federation of Gynecology and Obstetrics Stages I-IV) to in situ cervical carcinoma in 1988-1990 versus 1991-1995 was stratified by age (24 or younger, 25-44, 45-64, 65 or older) and race (all races, whites, blacks, Hispanics, Asian/Pacific Islanders).

Results: The mean ratio of invasive to in situ cervical cancer incidence for women at least 65 years old was lower in 1991-1995 compared with 1988-1990 (P <.001, 95% confidence interval 0.893, 0.954); and had decreased more than observed for women aged 45-64 and 25-44, for all races combined, and for white women. The decreased ratio of invasive to in situ cancer for blacks, Hispanics, and Asian/Pacific Islanders at least 65 years old was no different than the decreased ratio in younger women.

Conclusion: In California, in the 5 years after the 1990 change in Medicare funding statutes for cervical cytology screening, the ratio of invasive cervical cancer to in situ disease decreased more in Medicare-eligible patients than in younger women.