Ladera Ranch Residents Raise Concerns Over Elevated Ewing Sarcoma Cases

Children and teens in Ladera Ranch, California, are getting a rare bone cancer at a higher rate than the national average. (Photo: LA Times)

Ladera Ranch is a 4,000-acre planned community in southern Orange County, California. As per the 2020 census, this ranch had a population of 26,170. The residents of the ranch have now raised a cancer concern with the California Department of Public Health that children or young adults of the ranch are suffering from Ewing sarcoma, a very rare cancer that starts in bone or soft tissue. About 2.9 out of every 1 million kids get Ewing sarcoma each year in the US, but the number for Orange County is 3.1. At least six cases of Ewing sarcoma were reported between 2013 and 2024. “There definitely is cause for concern for members of this community,” Dr Janet Yoon, a pediatric hematologist-oncologist at City of Hope who specializes in Ewing sarcoma, said to the Los Angeles Times.

Parents believe there is something wrong in the ranch

LA Times spoke to Ladera Ranch resident Bonnie Regan, whose son Ryan died of this cancer in October 2025. Ryan was diagnosed with this cancer in 2017 when he was 29. He fought the cancer for eight years until it spread to his lungs, shoulder, brain, spine, lymph node, adrenal gland and stomach. "There is something wrong here. I had never even heard of this kind of cancer before," Regan said. With the growing number of cancer cases, the residents formed a group called Ladera Health Watch to gather health data. Initially, they focused on limiting pesticide use. Now they are concerned that the ranch sits on old oil and gas wells and probably that might have a connection with the cancer cases.

'This well is not to be built over'

The construction of the ranch began in 1998, and it was completed in 2006. Underneath the ranch are two abandoned oil wells but neither of them had a history of producing oil or gas. These wells were closed twice and the safety standards were checked. The LA Times report said that some residents are concerned that one of the wells may not have been resealed to today's standards. They have also found a handwritten note that said: "This well is not to be built over without further consideration". But it provided no explanation for the warning. "Active and abandoned oil and gas wells can spread carcinogens such as benzene, volatile organic compounds and radioactive material into surrounding soil, water and air. Proximity to wells has been linked with elevated rates of childhood leukemia and lymphoma," the LA Times report said. Kenneth Henderson, the supervisor, who wrote the note at that time said he did not recall why he added the warning, but “the well plugging may not have been up to the current standards.” California Geologic Energy Management Division spokesperson said CalGEM generally recommends that structures not be placed over sealed wells. Though wells which are plugged and sealed to current requirements are less likely to experience leakage, there is no guarantee, a spokesperson said.