The San Francisco Firefighters Cancer Prevention Foundation is pleased that we were able to offer the Galleri Multi-Cancer Early Detection test. We would like to take this opportunity to release the results and open the discussion on the importance of continued medical screenings. This was not by any means “a one and done” test.

Let’s first look at some statistics. We screened 1786 active and retired firefighters. Included in that number are some spouses of firefighters who paid out of pocket to be screened. We had 1177 tests completed by those over the age of 50. Out of all 1786 screened, 11 had a “cancer signal” detected. All 11 positive results were in patients greater than 50 years old. The positivity rate for patients over 50 was 0.93%. The positivity rate for all tested was .62%. Out of the 11 positive results, there have been 5 confirmed cancers and the 6 remaining patients showed no signs of cancer through imaging. The five confirmed cases were all asymptomatic further supporting our argument for our members to stay on top of all recommended screenings. The 6 patients that were possible false positives will be offered a free Galleri follow up test to confirm that their test was a false positive.

Did the Galleri test miss some cancers? The answer is yes. Three firefighters found out they had cancer through their private doctors after having the Galleri test that showed “no cancer signal”. Those cancers were melanoma, prostate cancer and lymphoma. Galleri’s medical liaison reviewed the sensitivity variation of Galleri for different types of cancer and discussed that since Galleri is a cancer SCREEN and NOT a DIAGNOSTIC test, it will not detect all cancers. Galleri is good at detecting more aggressive cancers, most of which we have no current cancer screening available. Galleri is not good at finding slower growing, more indolent cancers. The sensitivity rate is below 50% for the following cancers:

  • Thyroid 0%
  • Prostate 11.2%
  • Kidney 18.2%
  • Myeloid Neoplasm 20%
  • Uterus 28%
  • Breast 30.5%
  • Bladder 30.5%
  • Lymphoid Leukemia 41.2%
  • Melanoma 45.2%
  • Other 50.8%

The purpose of this follow-up is basically to communicate the strengths and limitations to those that participated in the screening and to future firefighters. We must remain vigilant and remember that this was a “screening” not a “diagnostic” test. It can detect some cancers, but not all. It is incredibly important that everyone continue guideline recommended screenings with your personal health care provider. Another important fact is Galleri is a “point in time” test, and doesn’t predict your risk for future cancer.

Galleri will continue to “fine tune” their test to overcome its current limitations. Our cohort results and ongoing studies that they are currently conducting will give them more data points to refine the current assay.

Overall cost of the Galleri screening, $1,170,000. This screening could not have been possible without the generous contributions of our donors.

Tony Stefani
President, SFFCPF