When former Pennsylvania Senator Arlen Specter died in mid-October, it was hard not to be struck by his unusual medical history, a 2-decade long battle against his serial development of three different types of cancer.
It turns out that Senator Specter’s tumor history, while still unusual, is growing increasingly more commonplace, the byproduct of improved success in treating cancer and boosting patient survival.
As patients undergo effective cancer treatment and live for years following their therapy, their risk for developing a second, and even a third independent, primary cancer grows.
Courtesy Bobjgalindo/Wikimedia Commons/Creative Commons License
A brain tumor, the first cancer to strike the late Senator Arlen Specter.
According to the definitive obituary in the Philadelphia Inquirer, his hometown paper, Sen. Specter, who died on Oct. 14 at age 82 from complications of non-Hodgkin’s lymphoma, first was stricken by cancer in the form of a brain tumor in 1993 (when he would have been about 63). After that came diagnosis and successful treatment of a second brain tumor in 1996, and treatment for Hodgkin’s lymphoma in both 2005 and 2008, followed by the non-Hodgkin’s cancer that led to his death.
Coincidently, also this month, a review appeared in the Journal of Clinical Oncology that updated current thinking about the risks and causes of second malignancies.
The review said, "Because of improvement in early detection, supportive care, and treatment, the 5-year relative survival rate for all cancers combined has increased steadily over the past few decades to reach 66.1% for patients diagnosed from 1999-2006. As of January 2008, there were approximately 11.9 million cancer survivors in the United States." (J. Clin. Oncol. 2012;30:3734-45 [doi:10.1200/JCO.2012.41.868]).
The review goes on to say, "The number of patients with multiple primary cancers is growing, with second malignant neoplasms now representing approximately 16% of cancers reported to the National Cancer Institute’s Surveillance, Epidemiology, and End Results Program (SEER)."
The review also discusses the multiple factors that can act, individually or in concert, to trigger second or higher-order cancers:
• Hereditary and familial risks that make a person more prone to develop cancer.
• Second malignancies triggered by antecedent cancer therapy, either radiotherapy or chemotherapy.
• Genetic predispositions that boost the risk for therapy-related second cancers.
• Shared etiologic factors among serial cancers that can include environmental or lifestyle influences.
In addition to these potential triggers, another factor entering the mix is a patient’s age at the time of exposure to a cancer trigger, as well as overall attained age.
While the SEER data put a rough estimate in place for the risk an American who today survives a first cancer faces for developing a second malignant neoplasm (16% of the rate for developing any type of cancer), it cannot address the question of how often cases come up like that of Senator Specter: the risk for serially developing three different cancers.
According to Dr. Marie E. Wood, an oncologist at the University of Vermont in Burlington and lead author of the JCO review, the three-cancer risk is currently unknown, but undoubtedly also growing.
"I am confident that they represent a small but growing number, just as the number of second malignancies are growing," Dr. Wood told me.
–Mitchel Zoler (on Twitter @mitchelzoler)