A new study by the Pentagon has found higher rates of cancer among military pilots, as well as the ground crews that maintain their airplanes, The Associated Press reported Sunday. 

While prior reports from the U.S. Department of Defense said military aviators did not have higher risks of cancer, this study shows markedly different results.

The yearlong study examined nearly 900,000 military pilots and ground crew who served from 1992 to 2017. It concluded that pilots “had an 87 percent higher rate of melanoma, 39 percent higher rate of thyroid cancer, 16 percent higher rate of prostate cancer, and a 24 percent higher rate of cancer for all sites.” Studies of the ground crew similarly determined they had a 19 percent higher rate of brain and nervous system cancers, a 15 percent higher rate of thyroid cancer, a nine percent higher rate of melanoma, a nine percent higher rate of kidney and renal cancers, and a three percent higher rate for all sites.

The study also noted that there are large gaps in overall military cancer cases, because there is “no Department of Defense data source containing complete data on cancer diagnoses prior to 1990.” As a result, the total rate of reported cancers among pilots and ground crew has likely gone underreported. 

AP noted that this study examined all military service branches, unlike prior research efforts that had only looked into Air Force pilots. This study “proves that it’s well past time for leaders and policymakers to move from skepticism to belief and active assistance,” retired Air Force Col. Vince Alcazar told AP.

However, there was a silver lining in this new report, as Axios noted that “both air and ground crews saw ‘lower or similar’ cancer mortality rates for all cancer types compared to the general population.”