Almost half of cervical and colorectal cancers in the United States are diagnosed in the late stages of the disease when treatment is unlikely to help, a US government survey said Wednesday.
Often, such cancers were detected later in elderly people and among blacks and Hispanics, said the survey by the Centers for Disease Control (CDC) which spanned 2004-2006.
"This report causes concern because so many preventable cancers are not being diagnosed when treatment is most effective," said Marcus Plescia, director of the CDC's Division of Cancer Prevention and Control.
"More work is needed to widely implement evidence-based cancer screening tests which may lead to early detection and, ultimately, an increase in the number of lives saved."
Nearly one-third of breast cancer cases were diagnosed late, with such incidences highest among women aged 70-79 years and black women.
Late-stage colorectal cancer was highest among black men and women, while cervical cancers tended to be found late among women aged 50-79 and Hispanic women.
The report said the "differences in late-stage cancer diagnoses may be partially explained by differences in screening rates in locations and among different demographic groups."
The US health care reform plan, which was backed by President Barack Obama and began phasing into effect in September, contains measures to help boost cancer screenings by waiving fees associated with those doctor visits.
The CDC described that plan as "an important first step to increasing the numbers of persons who receive these services."
Colorectal cancer kills about 50,000 people per year and is the second leading cause of US cancer deaths, after lung cancer. Around 40,000 women die annually of breast cancer.
Cervical cancer is one of the easiest to detect early with regular screenings, but results in about 4,000 deaths per year in the United States.