Features
Agent Orange and
Hematologic Malignancies
The Fog of War Still Hovers
M
ore than 40 years after the
Vietnam War, the fog of
Agent Orange hangs thick
over veterans and those providing
their medical care. Aging veterans suf-
fer from an extensive list of diseases,
including several hematologic malig-
nancies, deemed related, or possibly
related, to exposure to Agent Orange.
The number of affected veterans
will likely increase as new conditions
are added to the official list of “pre-
sumptive diseases” and as controver-
sies are resolved regarding which vet-
erans were affected (and how the U.S.
government should compensate and
care for them). Although the science
connecting Agent Orange exposure
and certain hematologic malignancies
is sound, the story of Agent Orange is
far from clear-cut. It is covered with
a sticky mist of politics, controversy,
blame, and denial.
48
ASH Clinical News
“Many cases we see in our clinics
may resonate back to historic events
that we don’t pay much attention to,
in part because it is difficult to dissect
the details,” said C. Ola Landgren,
MD, PhD, chief of the myeloma
service at Memorial Sloan Kettering
Cancer Center in New York, who has
extensively studied the link between
environmental exposures and multiple
myeloma (MM).
To help unravel the story, ASH
Clinical News spoke with Dr. Landgren
and ASH Clinical News Associate
Editor David Steensma, MD, about
the science behind Agent Orange, the
clinical considerations of exposure,
and the task of caring for ill veterans.
Making “The List”
The U.S. military sprayed Agent Or-
ange in military operations from 1962
to 1971. In 1969, it became widely
known that the 2,4,5-T component
of Agent Orange was inadvertently
contaminated with the potent dioxin
TCDD. (See SIDEBAR on page 50 for
a history of Agent Orange and its
uses.) In response to a growing body
of evidence linking dioxin toxicity to
adverse health effects and birth out-
comes in returning service members
and Vietnamese citizens, the military
stopped spraying Agent Orange in
January 1971.
In 1991, Congress passed the
Agent Orange Act, giving the U.S.
Department of Veterans Affairs (VA)
the authority to declare certain condi-
tions “presumptive” to exposure to
Agent Orange/dioxin and to compen-
sate affected veterans for treatment.
Qualifying servicemen and women,
their spouses, and their biological chil-
dren with these conditions are eligible
to receive compensation, health care,
and vocational training from the VA.
The list of conditions includes
ischemic heart disease, type 2 diabe-
tes, and a variety of hematologic and
other malignancies ( FIGURE ). The VA
also presumes that certain birth de-
fects, namely spina bifida, in children
of Vietnam and Korean War veterans
are associated with veterans’ qualify-
ing military service. Even decades
later, though, the list of covered condi-
tions remains in flux.
To address continuing uncertainty
about the long-term health effects of
Agent Orange in veterans, the 1991
Agent Orange Act also mandated that
the National Academy of Medicine
(NAM; formerly known as the Institute
of Medicine) perform periodic,
comprehensive reviews of scientific
and clinical information regarding the
health effects of exposure to sprayed
herbicides.
May 2017