Colorectal cancer is expected to claim the lives of 49,190 people in the United States this year. Unfortunately, low-income people – a group disproportionately affected by this preventable condition – are often unable to afford screening and testing to save their lives. This disparity is due to a loophole in federal law that needs to be remedied to save both money and lives.

Statistics show that screening can prevent colon cancer. About 63 percent of colon cancer deaths in 2010 were preventable by screening. Increasing screening use from 58 percent in 2013 to 80 percent by 2018 could prevent approximately 19 percent of deaths from colon cancer in 2020.

Low-income groups need screening the most. Among Medicare beneficiaries, those from low-income backgrounds have half the rate of screening of high-income groups.

This unfortunate scenario occurs in part because the U.S. Congress unfairly limits the ability of low-income Medicare beneficiaries to receive screening. This compounds other barriers and perpetuates long-standing disparities in mortality from colon cancer for seniors.

The Affordable Care Act (ACA) allows people to have a screening colonoscopy free of charge, but not for those who only have Medicare coverage. This is due to a loophole in federal law that compels Medicare to charge beneficiaries up to 25 percent of the cost of the test. This cost is borne by the patient if he or she does not have supplemental health insurance.

The Balanced Budget Act, a federal law that passed in1997, classifies a screening colonoscopy as a diagnostic test if a polyp, cancer, or other abnormal finding is discovered during the course of the procedure.

Medicare is prohibited from waiving the beneficiary's share of coverage for screening costs when something abnormal is found on the test, or it is done because another screening test was positive  -- all potential harbingers of life-threatening conditions, as the ACA had intended.

So, a Medicare beneficiary who does not have supplemental insurance could wake up from a screening colonoscopy that was expected to be at no cost to him or her and receive a bill because a polyp or cancer was found – the very reason the test was done in the first place. This policy imposes unnecessary out-of-pocket costs on people without means. A disproportionally high percentage of low-income seniors lack the supplemental insurance needed to cover care after a positive screening.

While the conflicting federal laws significantly inhibit the availability of screening and treatment to the neediest, they could also fuel unnecessary increases in national healthcare spending. The majority of people who develop colon cancer are at the Medicare age of 65 or older. There are currently an estimated 55.5 million Medicare beneficiaries in the U.S. Medicare spent $2 billion on approximately $3.8 million colonoscopies in 2013; in comparison, it spent $7.3 billion in 2010 on colon cancer treatment.

The Balanced Budget Act classification of colonoscopy reflects a time when colon cancer screening was incorrectly viewed as a one-time activity. In practice, screening is the series of clinical activities involved in identifying and testing patients and performing diagnostic confirmation when necessary. These activities include taking a biopsy to help plan treatment or performing a polypectomy, in which polyps are removed to prevent them from becoming cancerous.

It is time for the federal law to reflect the state of the science.

It is critical that Congress amend the Balanced Budget Act to allow Medicare to waive co-insurance and co-pay for all testing related to screening for colon cancer, including colonoscopies performed because another screening test was positive. Medicare stands to gain from avoiding treatment costs for cancers that could be prevented through screening. More importantly, this would make screening for colorectal cancer more affordable for low-income seniors. They at higher risk of the disease than any other group, but continue to be disadvantaged by current federal laws.

Chyke A. Doubeni, MD, MPH, is the chair and the Presidential Associate Professor of Family Medicine and Community Health at the University of Pennsylvania. He has federal funding to conducts research on colon cancer screening. More information is available from the article "Colorectal Cancer Health Disparities and the Role of US Law and Health Policy" in the May 2016 issue of the journal of Gastroenterology

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