While use of the standard therapy leading to the best outcome against locally advanced rectal cancer has increased over the past decade, only half of patients currently receive it, according to a new study.

The authors of the study say the underutilization could be explained in part by socioeconomic factors.

The study appears early online in Cancer.

Rectal cancer is a common disease in the United States.

An estimated 39,000 new cases are expected to be diagnosed in the United States in 2016, and there's been a worrisome increase in incidence rates in the younger population.

The management of rectal cancer has become more complex with evolving treatment regimens.

Over the past decade or so, neoadjuvant chemoradiation therapy (NACRT) followed by surgery has been established as a standard of care for locally advanced rectal cancer in the United States, based on studies that showed better outcomes.

For their new study, researchers from the American Cancer Society and Oregon Health & Science University used the National Cancer Data Base to identify 66,197 patients diagnosed with and treated for stage II-III rectal adenocarcinoma between 2004 and 2012.

They found the proportion of patients receiving NACRT, the established treatment, has increased significantly, rising from 42.9% in 2004-2006 to 50.0% in 2007-2009, and to 55.0% in 2010-2012.

Meanwhile, the proportion of other, less-favoured treatments, like chemoradiation after surgery or surgery alone, declined.

But while the use of standard therapy has increased, the report points out that only about half of patients with locally advanced rectal cancer currently receive the standard therapy as recommended by national guidelines.

Several factors were found to be associated with a lower chance of receiving the standard treatment: being treated at a facility with low or medium case volume; being of other than non-Hispanic white race/ethnicity; lack of private insurance; and residence in a neighbourhood with a lower education background.

"Unfortunately, with only 55% of US patients with locally advanced rectal cancer receiving the standard of treatment in the recent years, one must address the gap between the guidelines and the variable penetrance into routine clinical practice," write the authors.

Reference

Sineshaw, H. M., Jemal, A., Thomas, C. R. and Mitin, T. (2016), Changes in treatment patterns for patients with locally advanced rectal cancer in the United States over the past decade: An analysis from the National Cancer Data Base. Cancer.

Source: American Cancer Society