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Volume 84 � Number 3S � Supplement 2012 Poster Viewing Abstracts S517
applicator was constructed by attaching brachytherapy catheters at 1 cm
intervals to a 5 mm thick bolus. Two treatment plans were generated for
brachytherapy: one for Iridum-192 HDR and the other which assumed
treatment with 50 kVp EBT using the same applicator. A third plan was
generated for a 2 full arc 6 MV photon VMAT (also with a 5 mm thick
bolus). The target and organs at risk (OARs) were contoured on
a simulation CT scan. The prescription was 36 Gy in 8 fractions for a 9
cm � 12 cm � 1 cm target. The plans were optimized to a standard
target coverage (V100% > 98%) and to minimize dose to OARs using
Nucletron Oncentra MasterPlan (HDR), Varian BrachyVision (EBT) and
Eclipse (VMAT). We compared mean target dose, dose heterogeneity,
and doses to OARs.
Results: The target V100% and D90% were 98% and 104% (HDR), 100%
and 119% (EBT), and 98% and 102% (VMAT). The mean (and range from
minimum to 1cc maximum) target doses were HDR 119% (86-157%),
EBT 164% (86-271%), and VMAT 104% (96-108%). The Table
summarizes mean dose to OARs.
Conclusions: EBT provided the least dose to closest OAR (brain) due to
rapid dose fall-off of low-energy X-rays, but it resulted in higher mean
target doses and more heterogeneity than HDR and VMAT. HDR and
VMAT provided similar V100% and D90% target doses. As expected,
VMAT provided most dose uniformity. All methods resulted in acceptable
normal tissue doses, but they were lower for EBT and VMAT than HDR
specifically for this lesion located on the top of the skull. Comparative
dosimetry facilitates treatment modality selection for extensive superficial
lesions with complex surfaces, irregular contours, and close proximity to
Author Disclosure: S. Park: None. M. Kamrava: None. O. Kayode: None.
S.P. Lee: None. M.L. Steinberg: None. D.J. Demanes: None.
2798Fentanyl Pectin Nasal Citrate (FPNC) to Control Breakthrough Pain(BP) and Improve Dysphagia in Head-and-Neck Cancer PatientsReceiving Radiation Therapy (RT)I. Prieto,1 J. Pardo,2 A. Perez-Casas,1 J. Olivera,1 J. Luna,1 and J. Vara1;1Fundacion Jimenez Diaz, Madrid, Spain, 2Hospital General de Cataluna,
Purpose/Objective(s): To evaluate the breakthrough pain control and the
improvement of the dysphagia in head and neck cancer patients (HNCP)
who develop mucositis and moderate-severe dysphagia radiation therapy-
Materials/Methods: Eleven patients with breakthrough pain due to
radiation therapy-induced mucositis were selected to start treatment
with FPNC in order to relief the pain associated with swallowing.
Patients were already receiving an opioid treatment at total dose
equivalent to 40-80 mg morphine. Incidental pain was treated before
eating 4-5 times /day with a dose of 100-400 mg of FPNC. Data related
to tolerance, pain relief and efficient dose for swallowing maintenance
Results: Patients who adhered to the FPNC treatment reached satisfactory
pain control. Three patients chose do not receive the basal opioid treat-
ment, and then achieved BP relieve only with FPNC. The efficient dose of
FPNC was 200 mg in most of patients. Only 1 needed 400 mg. The mean
onset time of the pain relief was 7 minutes (range 5-10) in 6 patients, and
the mean response duration was 60 min (range 45-75 min). This relief
effect allowed oral feeding, nutritional parameters maintenance, and,
therefore, improvement in the patient’s quality of life. Also permitted
deliver RT treatment without interruptions.
Conclusions: BP management is difficult to manage and so are most
agents used to treat it. HNCP treated with radiation therapy develop oral
mucositis with severe breakthrough incidental pain associated with swal-
lowing, so a simple, rapid and strong analgesic is needed. The oral rescue
dose is likely to be inadequate for a significant percentage of these patients
with xerostomia and severe oral pain. The intranasal way eliminate this
problem and offers a rapid an efficient absorption. FPNC seems to be
particularly beneficial and well accepted in patients with BP due to radi-
ation therapy-induced mucositis.
Author Disclosure: I. Prieto: None. J. Pardo: None. A. Perez-Casas: None.
J. Olivera: None. J. Luna: None. J. Vara: None.
2800Prognostic Utility of Pretreatment Metabolic Tumor Volume, GrossTumor Volume, Maximum Standardized Uptake Value in Head-and-Neck Cancer Patients Receiving IMRTP. Romesser,1 B.A. Shah,1 M.M. Qureshi,1 S. Jalisi,1,2
R.M. Subramaniam,1,2 and M. Truong1,2; 1Boston University School of
Medicine, Boston, MA, 2Boston Medical Center, Boston, MA
Purpose/Objective(s): This retrospective study compared the prognostic
utility of pretreatment metabolic tumor volume (MTV), gross tumor
volume (GTV) and raw maximum standardized uptake value (SUVmax),
with respect to tumor control and survival in patients with head and
neck squamous cell carcinoma (HNSCC) undergoing intensity modu-
lated radiation therapy (IMRT) with or without concomitant
Materials/Methods: Between 2004 and 2009, 41 HNSCC patients who
underwent a pretreatment PET/CT and definitive IMRT were identified.
All PET/CT studies were retrieved from the electronic archival system
and reviewed on a MIMvista workstation (software version 4.1). Fused
PET/CT images were reviewed in axial, coronal, and sagittal planes.
SUVmax and MTV were obtained from the PET/CT scans. GTVs
manually contoured by the radiation oncologist were obtained from the
Dose Volume Histograms (DVH). The SUVmax was defined as the
maximum standardized uptake value within the tumor normalized to lean
body mass, MTV was defined as the tumor volume with FDG uptake
using a gradient-based (PET Edge) auto-segmentation method. Local
(LC), nodal (NC), distant (DC), overall (OC) control and overall (OS)
and disease free (DFS) survival were calculated using the Kaplan Meier
product-limit method. Receiver operator characteristic (ROC) curves
were constructed by plotting sensitivity versus (1-specificity) and
optimum cutoff values for above parameters were derived for endpoint
LC. Percent area under the ROC curves (AUC) and their 95% confidence
intervals were found. A probability value of less than 0.05 was consid-
ered statistically significant.
Results: Median follow up was 24.2 months (range, 2.7- 56.3 months).
The GTV and MTV were 22.2 cc, and 7.2 cc respectively. The median
SUVmax was 15.8. Patients with smaller GTVs (<22.2 cc) demon-
strated two-year actuarial LC rates of 100% versus 56.4% (pZ0.001)
and OS rates of 94.4% versus 65.9% (pZ0.045). Similarly, a smaller
MTV (<7.2 cc) correlated with improved LC and OS with two-year
actuarial LC rates of 100% versus 54.2% (pZ0.0003) and OS rates of
94.7% versus 64.2% (pZ0.040). Smaller GTV and MTV correlated with
improved NC, DC, OC and DFS. SUVmax did not correlate with LC
and OS when analyzed by median threshold. An exploratory analysis
using ROC curves constructed for the LC endpoint identified a cutoff
value of SUVmax of 19.3 (AUCZ73%, 95% CI 56% - 85%), GTV of
29.6 cc (AUCZ89%, 95% CI 75% - 97%), and MTV of 7.7 cc
(AUCZ81%, 95% CI 66% - 92%). Both GTV and MTV retained
significance using ROC optimized cutoff values. In all cases the MTV
was smaller than the GTV.
Conclusions: In HNSCC patients undergoing IMRT, MTV and GTV
demonstrate superior prognostic utility compared to SUVmax.
Author Disclosure: P. Romesser: None. B.A. Shah: None. M.M. Qureshi:
None. S. Jalisi: None. R.M. Subramaniam: None. M. Truong: None.