Pediatric ‘cancer cluster’ detected
Pediatric 'cancer cluster' detected
Rare illnesses found in Rye, Portsmouth, Greenland, New Castle and No. Hampton
State officials are monitoring what they say is a cancer cluster involving two rare types of pediatric cancers on the Seacoast.
“By definition, being the fact it’s a rare cancer and there’s a higher than expected small number of cases, it would meet the definition of a cancer cluster,” State Epidemiologist Dr. Benjamin Chan said during an interview Friday.
His comments follow the release of a 14-page report detailing the state Department of Health and Human Services’ investigation that began in March 2014 when they were “contacted by residents of Rye, NH, reporting concern about the number of cases of rhabdomyosarcoma (RMS) among children living in, or connected with, the Rye area.”
DHHS ended up looking into pediatric cancer cases in five Seacoast towns, including Rye, Portsmouth, Greenland, New Castle and North Hampton, according to the report and Chan.
That investigation ultimately determined that there was “a small number of excess pediatric RMS cancer cases … in the five town area of investigation, and that number was above what would be expected based on a comparison with the rest of Rockingham County,” the report states.
The state released the report this month after investigating the RMS cases, Chan said.
He described RMS cancers as “a rare form of soft tissue cancer” that can occur in either children or adults.
The report also states that RMS cancers are "the most common soft tissue tumor of childhood and represents about 3-4 percent of all childhood cancers."
“We put a lot of time and effort into creating the report and tracking down leads as we found them to try to identify and explain” how the children contracted cancer, Chan said.
As they were investigating the RMS cancer cases, “we saw a very small number of (pediatric) lung cancers,” Chan said.
All of the cases they saw were “of a single rare type called pleuropulmonary blastoma (PPB),” according to the report.
“Seeing it in children is a little bit odd,” Chan said.
But like the RMS cancer cases, even though they were seen at a higher rate than expected, Chan stressed “there were very few cases,” which he characterized as “less than five cases over 10 years.”
Privacy laws forbid him from saying exactly where the cancers were seen, how many children contracted them or the outcome of their cases, Chan said.
Asked how concerned parents should be about the news concerning the cancer cluster, Chan said, “Anytime you talk about cancer and kids I know and expect parents will be concerned.”
But he said because there were so few cases, he hopes parents will find “some level of reassurance.”
Chan stressed that because of the investigation DHHS officials don’t believe the rare cancers were caused by any environmental exposure or “behavioral risk factors.”
Chan acknowledged that state health experts don’t know why the children were diagnosed with the rare cancers.
“In the majority of cases nationally they don’t have an identifiable cause,” Chan said Friday. “There are genetic and familiar cancer syndromes associated with RMS, but we can’t rule that in or out.”
The report on the cancer clusters pointed out that some people “expressed concerns over potential environmental contaminants and exposure related to proximity to the Schiller Station coal-fired power plant, Seabrook Station nuclear power plant and Pease Tradeport,” according to the report.
Portsmouth closed its Haven well in May 2014 after the Air Force found levels of perfluorooctane sulfonic acid (PFOS) 12.5 times higher than the EPA’s Provisional Health Advisory (PHA).
The EPA classified PFOS and perfluorooctanoic acid, or PFOA, which was also found in the Haven well at the former Pease Air Force Base, but below health advisory levels, as “contaminants of emerging concern.”
PFOS and PFOA are a class of chemicals known as perfluorochemicals. PFCs were found in the city-owned Smith and Harrison wells at the former base but never above the PHA.
But Chan said Friday there’s nothing in the scientific literature that connects PFC exposure to either one of these childhood cancers.
They also looked to see if the pediatric cancer cases were grouped geographically around any exposure to either Schiller or Seabrook Station.
“We looked at are they clustered around Schiller Station for example, and the answer is no,” Chan said.
DHHS officials will continue to monitor cases of both of the pediatric cancers “for at least a year,” Chan said, but they aren’t doing any further health studies at this time.
“The Centers for Disease Control and Prevention actually have guidelines about how and when” to do more studies, Chan said, but these cases don’t meet their standards.
Dr. Tom Sherman, a gastroenterologist and state representative from Rye, said he attended a meeting between Chan and a group of concerned parents.
There were no parents of the children who were diagnosed with cancer at the meeting, which took place in Rye a couple of weeks ago.
“They were just concerned parents after what’s happened with the water contamination at Pease and the proximity to Seabrook and Schiller stations,” Sherman said.
The parents wanted to know if there was a cluster and if “their kids were at risk,” Sherman said Friday.
He agreed the pediatric cases “technically represent a cluster,” but said because “there are such small numbers,” it’s hard to believe the cases were due to an environmental exposure.
“What reassures me is that they (DHHS) took this so seriously and they’re planning to follow up with the community,” he said.
Chan said he will meet with Rye's selectmen in the next couple of weeks.
Dr. Jack van Hoff, the chief of pediatric oncology at Dartmouth-Hitchcock Medical Center, said both types of cancers studied in the report are very rare.
For example, there are only about 350 cases nationally each year of RMS cancers, van Hoff said during an interview Friday afternoon.
The pediatric oncologist stressed he would “not be concerned” by the news about the cancer cluster, saying he believes it is a “random event.”
“When they are in fact random, some happen right next to each other,” van Hoff said.
He stated that the “study of cancer clusters has been particularly unrevealing for the most part.”
Absent some kind of “environmental catastrophe,” where children are exposed to carcinogens, most cancer clusters “pretty much don’t give us any useful information,” he said.
Many types of pediatric cancers are actually “a cancer of developmental tissue or fetal tissue,” van Hoff said.
Probably in about one in 10,000 people, cells that for some reason didn’t go through the full maturation process “start to grow in an uncontrolled manner and create cancers,” he said.
“These events are random developmental errors that never have been associated with environmental exposures,” van Hoff said.
“It’s probably the same thing that causes all of them, a developmental error that just happens some time,” he added.
van Hoff understands why it’s “philosophically unsatisfying,” for parents to hear that kind of an explanation.
In fact, over time, the rates of childhood cancers have been “remarkably stable although the death rates have gone down,” due to better treatment, he said.
“Childhood cancer is a huge disastrous kind of thing to happen to a family, but in fact most kids who get it, survive and go on to lead adult lives,” he said.
Here is a weblink to the full report, Investigation of Rhabdomyosarcoma (RMS) Cases in the Rye Area: http://goo.gl/UYq1EZ