(HealthDay News) – Women whose cervical cancers are detected by cervical smears are much more likely to survive than women whose cancers are symptomatic, according to a study published online March 1 in BMJ.
To rule out lead-time bias, Bengt Andrae, MD, from the Karolinska Institutet in Stockholm, and colleagues examined survival in 1,230 women diagnosed with cervical cancer in Sweden from 1999 to 2001.
After an average of 8.5 years, the researchers found that 92% of women diagnosed by Pap smear were cured compared with only 66% of women whose cancers were symptomatic. Among symptomatic women, the cure rate was 14% higher for those who had undergone screening according to recommendations, than among those overdue for screening. The cure proportions were similar for almost all histopathologic types and were closely associated with the International Federation of Gynecology and Obstetrics stage. Even after adjusting for stage at diagnosis, the cure rate was 15% higher for women who had been screened.
“Detection of invasive cancer by cervical screening implies a favorable prognosis compared with cancer being detected on the basis of symptoms,” Andrae and colleagues conclude. “The effect was stronger than what is reflected in down-staging and was not attributable to lead-time bias.”