Written in Blood
Study Identifies Two Measures of Tumor Burden for Risk Stratification
of Patients With Hodgkin Lymphoma
The presence of bulky disease is commonly
used as one factor in categorizing patients
with early-stage Hodgkin lymphoma (HL)
as having either favorable or unfavorable
risk, as well as to determine whether patients
can safely de-escalate therapy without com-
promising disease control. However, because
definitions of bulky disease vary, re-
searchers have hypothesized that other,
three-dimensional measurements
could improve risk stratification and
the quantification of disease burden.
Mani Akhtari, MD, of the
Department of Radiation Oncology
at the University of Texas Medical
Branch Hospitals, and co-authors
assessed whether two measures of
tumor volume on F-fluorodeoxyglucose
positron emission tomography/
computed tomography (PET/CT) –
specifically metabolic tumor volume
(MTV; total volumetric sum of all
areas of disease) and total lesion
glycolysis (TLG; volumetric sum
adjusted for standardized uptake
value) – could reliably stratify risk
among patients with early-stage HL.
According to results published
in Blood, MTV and TLG predicted
which patients with early-stage HL
would have worse outcomes. “Most
importantly, we have shown that not
all patients with early-stage, unfavor-
able HL are the same,” the authors
noted. “In fact, two distinct categories
can be discerned by the MTV or TLG,
into low and high disease burdens.”
The investigators retrospectively
reviewed the records of all adult pa-
tients diagnosed with HL who were
treated at the University of Texas MD
Anderson Cancer Center in Houston
between January 2003 and Decem-
ber 2013. Disease was delineated on
pre-chemotherapy PET/CT scans by
two methods: manual contouring
and sub-thresholding of these con-
tours. Sub-thresholding determined
tumor volume with standard uptake
volume ≥2.5. MTV; TLG measures
were extracted from the threshold
volumes (MTV t , TLG t ), as well as from
the manually contoured soft-tissue
volumes (MTV st , TLG st ).
They identified 267 patients
(median age = 32 years; range = 18-95
years) with Ann Arbor stage I or II dis-
ease and a combined initial PET/CT scan
(separate PET and CT images merged
into a single image). Patients with all
histologic HL subtypes were included,
except those with nodular lympho-
cyte-predominant HL. Patients were
excluded if they had a follow-up of six
months or less, unless they experienced
disease progression or death.
For this study, the researchers
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ASH Clinical News
defined bulky disease as any nodal mass
or conglomerate greater than 10 cm in
the axial, sagittal, or coronal dimensions.
Patients were classified with either unfavor-
able (n=178; 16%), favorable (n=74; 28%),
or stage IIB-advanced (n=15; 6%) disease.
Most (n=224; 84%) had stage II disease.
The most common treatment regimen
patients received was ABVD (doxorubi-
cin, bleomycin, vinblastine, dacarbazine;
n=239; 89%), and 250 patients experienced a
complete response following chemotherapy.
Three-quarters of patients (n=187) went on
to receive consolidative radiation therapy at a
median dose of 30.6 Gy (range =