Unearthed notes from 20 years ago shed light on childhood cancer mystery at California community
Rediscovered notes from the developer of a ritzy California community are raising questions about the cause of an unusually high number of rare cancer cases among children in the area.
In Ladera Ranch, a wealthy master planned community of about 25,000 just east of Laguna Beach, there have been at least six confirmed cases of Ewing sarcoma between 2013 and 2024.
The incredibly rare and painful form of cancer, which is diagnosed in just 200 people in the US annually, disproportionately affects children and teenagers. It grows in bones or soft tissue, and unless caught early, has a survival rate of just 30 percent.
Ladera Ranch parents who have buried their children who suffered from the disease have been trying for years to understand what caused it, and why it appears to be relatively common in their community.
Theories include heavy pesticide use in the area and a nearby landfill, but handwritten notes present in the archives of Ladera Ranch’s development company, DMB Development, have raised fresh concerns.
The notes, which appear to have been scribbled in the early 2000s when Ladera Ranch was under construction, say: ‘This well is not to be built over without further considerations.’
In 2002, DMB Development re-sealed a pair of abandoned oil wells to ensure that they met contemporary safety standards. The notes were written on a Department of Conservation permit and also appear typed in the final report of well abandonment.
The wells did not have a history of producing oil or gas, and there is no evidence that they are connected in any way to cases of Ewing sarcoma in Ladera Ranch.
In Ladera Beach, California, there have been an unusually high number of cases of Ewing sarcoma, an incredibly rare form of cancer, between 2013 and 2024
Handwritten notes in the files of Ladera Beach’s developer have raised fresh questions about the cause of the rare cancer cases
Lily Dalton, a resident of Ladera Ranch, died aged 23 from Ewing sarcoma. She is one of at least six people to have contracted the extremely rare form of cancer in the community since 2013
The Department of Conservation told the Los Angeles Times that the note’s presence in the final report may have been a ‘clerical error.’
However, one of the handwritten notes also said ‘put on final letter.’ The Department of Conservation did not comment on that message when the Times asked about it.
The notes do not explain why construction should potentially be avoided on top of the wells, and it is unclear whether there was any ‘further consideration.’
The presence of the notes in DMB Development’s files raises more questions than answers for Ladera Ranch residents who have been demanding investigations into potential causes for Ewing sarcoma cases in their community.
Bonnie Regan, whose son Ryan died aged 36 in October 2025 from Ewing sarcoma, told the LA Times: ‘There’s something wrong here. I had never even heard of this kind of cancer before.’
Brian Dalton, who lost his 23-year-old daughter Lily to the disease in January, told the California Post he suspects pesticides caused her cancer but said he wants a broader investigation.
‘When something this unusual happens, families deserve answers,’ Dalton told the outlet.
‘If there is even a possibility that environmental exposures, including pesticides or any other factor, could be contributing, then those possibilities deserve a thorough, transparent, independent investigation,’ he added.
Lily is pictured partway through her cancer treatment. Her father demanded an investigation into Ladera Ranch’s environment after she died
Brody Matteson (center back) died from Ewing Sarcoma at the age of 17 in March. His father said he wants to find out what caused his son to fall ill
Dustin Matteson, whose 17-year-old son Brody died from Ewing sarcoma in March, told the Times: ‘It feels like where we live, and with the high number of cases, it’s a place where you should be able to find out what caused it.’
Despite the lack of any tangible connection between the sealed wells or other theories about the cause of Ewing sarcoma cases in Ladera Ranch, experts say that grieving families are right to be asking questions, though they have also cautioned against jumping to conclusions.
Karen Lincoln, director of the Center for Environmental Health Disparities Research at UC Irvine, told the California Post: ‘We don’t know that the well is causing harm.
‘But residents are telling us they are concerned about a potential environmental health risk. They deserve a serious, transparent response.’
Dr Janet Yoon, a pediatric hematologist-oncologist at City of Hope who specializes in Ewing sarcoma, told the LA Times that it would be ‘incredibly challenging’ to prove a link between the cases in Ladera Ranch.
But she did say that the number of cases in the community appeared unusually high and said: ‘There definitely is cause for concern for members of this community.’
