(SALT LAKE CITY)—People who develop tumors in their pituitary gland have a significantly higher risk for other, unrelated types of cancer—and so do their relatives, a new study using records from the Utah Population Database (UPDB) has found.
University of Utah researchers report in the Journal of Neurosurgery that of 591 people in the UPDB who had pituitary tumors, 16 had malignant pituitary tumors and 77 others had primary tumors of a different type from pituitary. The total of 93 people with tumors among that group was significantly higher than the 71 cases expected. The researchers cited the risk for developing prostate cancer as being significantly higher in those with pituitary tumors.
Their relatives—ranging from parents and siblings to aunts and uncles to grandparents and first cousins—had significantly higher risks for developing colon, prostate, kidney and other types of cancer. The risk for getting any particular cancer depended on how closely related an individual was to the person with the pituitary tumor.
"Using this remarkable database (UPDB), we previously had determined that pituitary tumors cluster in families," says Lisa Cannon-Albright, Ph.D., professor of medicine and chief of the Division of Genetic Epidemiology in the School of Medicine. "Given that information, we wanted to know if someone was predisposed to a pituitary tumor, would their relatives be as well, and if so, would it mean we'd found evidence for a new gene or syndrome?"
Pituitary tumors account for almost 7 percent of primary brain and central nervous system tumors, and their prevalence is estimated at between 14 percent and 23 percent, respectively, according to, William T. Couldwell, M.D. Ph.D., professor and chair of neurosurgery at the University of Utah, who conducted the study with Cannon-Albright.
The UPDB is an electronic database of genealogical and demographic records representing more than 7.5 million deceased and living Utahns. The genealogical records date to the first Mormon pioneers and span as many as 11 generations in some families. The UPDB is linked to Utah state vital records and is updated annually with data from the Utah Cancer Registry, state Department of Health and driver license records. This unique aggregation of records gives researchers an ideal chance to study cancer and other diseases in large families.
Among the 575 people whose pituitary tumors were not malignant, the researchers looked at the UPDB records of their first-, second- and third-degree relatives. First-degree relatives are those with the closest genetic connection—parents, full siblings and offspring. Second-degree relatives are further removed and include aunts, uncles, half-siblings, nieces, nephews and grandparents. Third-degree relatives are the furthest removed genetically and include first cousins, great grandparents and great grandchildren.
To determine the risk for cancer, Cannon-Albright and Couldwell compared the occurrence of tumors among relatives of those with pituitary tumors with those of the UPDB as a whole. They found that the risk for developing malignant pituitary tumors was not significantly higher among relatives, but the risk for developing any type of cancer was 1.27 times higher among first-degree relatives, 1.16 times higher for second-degree relatives, and 1.06 times higher for third-degree relatives.
Among the types of non-pituitary cancers that were of highest risk among relatives, malignant peripheral nerve sheath tumors, a rare cancer of the connective tissue between nerves, was five times more likely in second-degree relatives. The next highest risk was among first-degree relatives, whose risk for anal cancer was 2.88 times higher. Following that, the risk for first-degree relatives getting female genital cancer was 2.57 times higher than average.
The risk for getting tumors of the central system was 2.46 times higher among third-degree relatives, while the risk for getting biliary cancer (non-gall bladder) was 2.37 times higher for second-degree relatives. The risk for pancreatic, stomach, prostate, and lip cancer was also higher among relatives, as were non-Hodgkin's lymphoma and chronic lymphocytic leukemia.
"The data in the UPDB indicate there is a significantly elevated co-prevalence of other tumors among people harboring pituitary tumors, and their relatives," Couldwell says. "Our study suggests that common genetic or environmental co-mechanisms do play a role in tumor development among people with pituitary tumors and their relatives."
The study results might be used for screening protocols and counseling people with pituitary tumors and their relatives, according to Couldwell and Cannon-Albright.