What is DIPG?
Ocean Springs pediatrician Dr. Van Wurm reported the third case of a rare and inoperable brain tumor known as diffuse intrinsic pontine glioma, or DIPG, to the Mississippi State Department of Health.
“In June 2017, I contacted the State Department of Health epidemiology department to confirm that there was indeed an increased incidence of DIPG during the time frame 2009 to 2017 in Ocean Springs,” Wurm said. “After conferring with another local pediatrician, I brought to the epidemiologists’ attention that there were three cases of DIPG in Ocean Springs between 2009 and 2017.
“They looked at population data from the time period and confirmed that there was an increased incidence of DIPG,” Wurm said. “Their response did caution that, statistically, three cases made drawing any conclusions about causality versus random chance difficult.”
The Sun Herald asked to interview Paul Byers, epidemiologist for the Department of Health in Jackson, about the number of children in the Ocean Springs area who have battled DIPG. Byers responded to an email to the questions, but he declined an in-person interview. Liz Sharlot, Department of Health spokeswoman, said there was nothing more for Byers to address other than what he already addressed.
Here are his email responses:
Q: What is the criteria to prompt officials to investigate for a possible cluster of cases if a rare disease like DIPG, or diffuse intrinsic pontine glioma, is diagnosed in a relatively small community?
A: The Mississippi State Department of Health (MSDH) did a statistical evaluation of a possible cluster of three cases of DIPG in a city on the coast in response to a physician concern. DIPG is a rare cancer with an annual incidence (of) between 300-400 cases in the U.S. or 1-2 cases per 100,000 population. There are no known environmental exposures, radiation sources or genetics related to the cause of DIPG.
Q: What is the protocol for such investigations?
A: The MSDH Office of Epidemiology watches occurrences and trends of reportable and chronic diseases, investigates outbreaks of diseases, helps interrupt outbreaks or disease problems, and reports morbidity incidence and trends to the medical community and other target groups.
Q: What specific diseases in the state have prompted such an investigations? Where and when did these occur? Are investigations currently under way for any type of cluster in the state? Have their been previous investigations into possible clusters for health-related issues? If so, what was the subject matter and where and when were they conducted along with any findings?
A: Investigating potential clusters and other diseases is a part of our day to day operations — we cannot enumerate all investigations.
Q: What would need to happen for officials to start looking into whether the number of DIPG or cases out of Ocean Springs are statistically significant?
A: While the rate of DIPG in the small city was elevated over the time frame, it is difficult to draw any conclusions from such small numbers of rare events.
Q: What are the number of DIPG cases diagnosed in the last 15 years in the state? I’d like to get a breakdown by year and county, though the Mississippi Cancer Registry does not have a breakdown specific for DIPG. I would think the Health Department would.
A: The cancer data we have access to is from the MS cancer registry, so our data is the same. Because of the rarity, observation of the incidence of DIPG in a specific geographic area would need to be evaluated over a number of years to estimate a rate with any statistic stability. Because of the rarity and the fact that the city has a small population, a rate can easily be halved or doubled with the exclusion or inclusion of a single case.
Q: What are the annual numbers by county of pediatric brain cancers in the state over the last 15 years?
A: The MS cancer registry would be able to provide numbers of childhood pediatric brain cancers over the last 15 years — but probably not by county since so rare there will be concerns for family/patient privacy.
Q: Has the Health Department received any inquires or complaints regarding the DIPG cases in the state and if so, what are the concerns?
A: The MSDH did a statistical evaluation of a possible cluster of 3 cases of DIPG in a city on the coast in response to a physician concern.