PROFFERED TALKS Winner of Best Presentation Award
T01 SPECT/CT Localization of Oral Radioiodine Activity after Thyroid Cancer Therapy: A Retrospective Study and In Vitro Assessment
Jared S. Burlison, M.D., Ph.D.,1 Joanna R. Fair, M.D., Ph.D.,1* Michael F. Hartshorne, M.D.,1 Alan M. Voda, DDS,2 F. Hadley Cocks, Ph.D.3 1Department of Radiology, University of New Mexico Health Sciences Center; 2Private Practice, Albuquerque, NM; 3Department of Mechanical Engineering and Materials Science, Duke University
*Corresponding Author/E-mail: JFair@salud.unm.edu
Objectives: We sought to further localize radioiodine (131I) activity in the mouth as visualized on routine imaging after thyroid cancer therapy.
Methods: We performed a retrospective review of all patients who underwent thyroid cancer therapy with 131I sodium iodide at our institution from August 2009 through March 2011 whose post-therapy imaging included SPECT/CT of the neck. Separately, we performed in vitro 131I binding assays with dental gold and amalgam to characterize these interactions.
Results: Of the 64 patients reviewed, 53 (83%) had dental fillings, and of those, 48 (91%) demonstrated oral 131I activity preferentially localizing to those fillings. Observationally, 131I also localized to other metallic and non-metallic dental hardware such as dental veneers, palate expanders, and tooth implants. Edentulous patients often had 131I activity along the gum lines, suggesting adherence to denture adhesive.
In vitro, dental amalgam and gold bound 131I in a time-dependent manner over 16 days. Despite subsequent washings with normal saline, significant 131I activity (68% for gold and 12% for amalgam) was retained by the dental material. Additional washings with saturated solution of potassium iodide (SSKI) partially displaced 131I from amalgam (10% removed), with near-total displacement of 131I from gold (99.6% removed).
Conclusions: As shown by SPECT-CT, post-therapy 131I in the oral cavity commonly localizes to dental fillings. Furthermore, in vitro studies demonstrate partially reversible binding of 131I to dental metals.
Winner of Best Abstract Submission Award
T02 Cost-Effectiveness of Y-90 Zevalin® (ibritumomab tiuxetan) Versus Rituxan® (rituximab) Consolidation Therapy for Follicular Lymphoma in a Single-Payer Healthcare System
Niraj R. Patel, MD1, Christie Gutierrez, CNMT2, Elizabeth Rogg, MD3, Yuval Raizen, MD3, Stanley Thai, PharmD3, and Luis A. Tamara, MD2
1Division of Nuclear Medicine, Department of Radiology, Baylor College of Medicine, Houston, USA; 2Division of Nuclear Medicine, Department of Radiology, Michael E. DeBakey VA Medical Center, Houston, USA; 3Department of Hematology and Oncology, Michael E. DeBakey VA Medical Center, Houston, USA; Contact NirajP@bcm.edu; Special Thanks: Brian Dahl, PharmD in the San Diego VA Medical Center
Introduction: The radioimmunotherapy agent yttrium-90 ibritumomab tiuxetan (Zevalin®) is effective consolidation therapy for follicular lymphoma (FL).1 Studies suggest it is more effective than rituxomab (Rituxan®) maintenance therapy in extending progression free survival in refractory FL.2,3 While Y-90 Zevalin® has demonstrated efficacy, its cost effectiveness as consolidation therapy for FL in a single-payer system remains unclear.
Methods: Costs of Y-90 Zevalin® and Rituxan® doses were obtained from Spectrum Pharmaceuticals and the South Central VA Healthcare Network (VISN 16) Formulary, respectively, in October 2011. Only costs of doses were considered because material costs were considered marginal and labor costs fixed. The Y-90 Zevalin® protocol is based on FDA-approved guidelines, which state no need for an In-111 Zevalin® scan.4 Rituxan® maintenance therapy of 375 mg/m2 IV every 2 months for 2 years is the standard of care of the Houston VAMC Oncology service.5 Some oncologists however prefer Rituxan® every 3 months for 2-year maintenance therapy.6
Results: Cost of a single dose of 0.4 mCi/kg of Y-90 Zevalin® including two doses of low-dose Rituxan® is $24,878. Cost of all doses of Rituxan® for standard 2-year maintenance therapy is $22,830. If Rituxan® is given every 2 months for 2-year maintenance therapy, the cost is $34,244.
Conclusion: The Y-90 Zevalin® regimen, including low-dose Rituxan®, costs 27% less than the standard of care 2-year Rituxan® maintenance regimen for refractory follicular lymphoma at the Houston VA Medical Center. The Y-90 Zevalin® regimen costs 8% more than an alternative 2-year Rituxan® maintenance regimen characterized by less frequent infusions. Because studies show it is at least as effective as Rituxan® in prolonging progression free survival, and more convenient to the patient, Y-90 Zevalin® is a viable alternative for refractory follicular lymphoma in a single-payer healthcare system.
1. Morschhauser F, Radford J, Hagenbeek A, et al. Phase III Trial of Consolidation Therapy With Yttrium-90–Ibritumomab Tiuxetan Compared With No Additional Therapy After First Remission in Advanced Follicular Lymphoma. J Clin Onc 2008; 26(32):5156–5164.
2. Hagenbeek A. Radio-immunotherapy consolidation versus rituximab-maintenance in first remission follicular non-Hodgkin’s lymphoma. The case for RIT. Ann Oncol 2011;22(4): iv81–iv82.
3. Witzig TE, Flinn IW, Gordon LI, et al. Treatment with ibritumomab tiuxetan radioimmunotherapy in patients with rituximab-refractory follicular non-Hodgkin’s lymphoma. J Clin Oncol 2002;20:3262–9.
4. Kits for the Preparation of Indium-111 (In–111) Ibritumomab Tiuxetan and Yttrium–90 (Y–90) Ibritumomab Tiuxetan. 2001. Hosted by FDA.
5. Buske C. Consolidation Therapy for Follicular Lymphoma. European Oncology 2008;4(1):41–4.
6. Salles G, Seymour JF, Offner F, et al. Rituximab maintenance for 2 years in patients with high tumour burden follicular lymphoma responding to rituximab plus chemotherapy (PRIMA): a phase 3, randomised controlled trial. The Lancet 2011; 377:42–51.
P01 Case Report : In-111 Pentreotide SPECT-CT Scan as an Aid in the Diagnosis and Follow up of a Rare Mixed Head and Neck Metastatic Lesion.
Anshul Agarwal, MD, PhD, Jason Pond, MD, Orhan K. Öz, MD, PhD.
Nuclear Medicine Division, Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX.
Introduction: Head and neck composite tumors with mixed neuroendocrine features are rare and on review of the English language literature only seventeen cases reports are encountered. We hereby illustrate the role of In-111 Pentreotide SPECT CT imaging in a rare case of a 61 year old male diagnosed with mixed carcinoma of the larynx.
Method and Results: The patient is a 61 year old male with head and neck squamous cell carcinoma. At the time of initial diagnosis, total laryngectomy with neck dissection revealed a moderately differentiated invasive squamous cell carcinoma in the larynx and neuroendocrine differentiation positive for Synaptophysin, Chromogranin, CK7 and CEA (m) in bilateral Level-1 cervical lymph nodes mixed with metastatic squamous cell carcinoma in multiple other nodes. A 1 year follow up surveillance CT scan revealed a 4 cm mass involving the left ninth rib. Histologic evaluation of the lesion revealed similar neuroendocrine features as in Level-1 cervical nodes at the time of initial diagnosis of laryngeal cancer. At the time, the lesion was considered to originate from an occult neuroendocrine primary. To localize the primary, a whole body In-111 Pentreotide scan was performed along with thoracic SPECT-CT. The scan revealed radiotracer avidity in the left 9th rib lesion without any other abnormal uptake. In-111 Pentreotide SPECT CT imaging was repeated annually during 3 years of follow-up. All repeat scans showed this lesion without scintigraphic evidence of any other primary disease. Owing to the facts that the 9th rib lesion had Pentreotide avidity, histopathologic similarity to the Level 1 cervical nodes at the time of initial diagnosis, and the absence of a Pentreotide avid primary on repeated scintigraphy, this lesion was considered to be metastatic from the head and neck mixed tumor. A resection of this lesion was recommended.
Conclusion: This is the first such case emphasing the utility of In-111 Pentreotide SPECT CT imaging in the diagnosis and follow up of rare metastatic mixed head and neck neuroendocrine tumors. In-111 Pentreotide SPECT CT imaging can play an important role in the evaluation and management of mixed head and neck neuroendocrine tumors in that it may permit exclusion of occult neuroendocrine primaries.
1. Jaiswal VR, Hoang MP. Primary combined squamous and small cell carcinoma of the larynx. A case report and review of the literature. Arch Pathol Lab Med 2004;128:1279–1282.
2. Gitika Aggarwal, Lana Jackson, Suash Sharma Primary combined small cell carcinoma of larynx with lateralized histologic components and corresponding sidespecific neck nodal metastasis: report of a unique case and review of literature. Int J Clin Exp Pathol 2011;4(1):111–117.
3. Barbeaux A, Duck L, Weynand B, Desuter G, Hamoir M, Gregoire V, Baurain JF, Machiels JP. Primary combined squamous and small cell carcinoma of the larynx: report of two cases and discussion of treatment modalities. Eur Arch Otorhinolaryngol 2006;263: 786–790.
4. Ferlito A, Recher G, Caruso G. Primary combined small cell carcinoma of the Larynx. Am J Otolaryngol 1985; 6(4): 302–308.
5. Gianoli GJ, Butcher RB, Martin EJ. Composite tumor of the larynx. Ear Nose Throat J 1992;71(2):81–82, 85–87.
6. Barnes L. Neuroendocrine tumors. In: WHO classification of tumors, Pathology and Genetics, Head and Neck Tumors (eds: Barnes L, Eveson JW, Reichart P, Sidransky D), 2004, pp.135–139.
7. Gibril F, Reynolds JC, Chen CC, et al. Specificity of somatostatin receptor scintigraphy: a prospective study and effects of false-positive localizations on management in patients with gastrinomas. J Nucl Med. 1999;40:539–553.
8. Gibril F, Reynolds JC, Doppman JL, et al. Somatostatin receptor scintigraphy: its sensitivity compared with that of other imaging methods in detecting primary and metastatic gastrinomas. Ann Intern Med. 1996;125:26–34.
P02 Evaluation of CycloSamTM, Sm-153-DOTMP, as a therapeutic bone-seeking radiopharmaceutical
Simon, Jaime (Jim)1; Frank, R. K.1; Ueno, Naoto T.2; Wendt, Richard E.2 Selting KA3, Lattimer JC3, Ketring AR4, Henry CJ3,5
1IsoTherapeutics Group LLC, Angleton, TX; 2UT M. D. Anderson Cancer Center, Houston, TX; 3University of Missouri Department of Veterinary Medicine and Surgery, Columbia, MO; 4University of Missouri Research Reactor, Columbia, MO; 5University of Missouri, School of Medicine, Department of Internal Medicine, Division Hematology and Oncology, Columbia, MO.
Introduction: A saturation effect has been reported for the bone-seeking radiopharmaceutical Quadramet (Sm-153-EDTMP). CycloSamTM, Sm-153-DOTMP, is theoretically superior because of its more favorable ligand-to-metal ratio (1.5:1 vs. 273:1). This study looked for CycloSam saturation effects and assessed its biodistribution in rats. Localization to sites of bone tumors in dogs was shown and myelosuppression or other toxicity was evaluated.
Methods : Dosages of CycloSam corresponding to 2, 4, 6, 8 and 10 Ci in humans were administered to five cohorts of rats to assess saturation. Animals sacrificed at 3 hours were dissected and assayed. Additionally, biodistribution was assessed in three cohorts of rats that were sacrificed at 2, 24, and 48 hours.
Dogs with spontaneously-occurring bone cancer recruited from the hospital population at the University of Missouri Veterinary Medical Teaching Hospital were treated with 1 mCi/kg CycloSam intravenously and monitored weekly.
Results : In the saturation study, the slope of the linear regression for each of the sampled tissues of the %ID vs. dosage was not significantly different from zero (P < 0.05). In the biodistribution study, 50.3% ± 3.8% of the administered activity was in the excreta by two hours. The skeletal %ID was 40.5% ± 1.9%. In the dog study, treatment was well tolerated. There was excellent correlation between pretreatment Tc-MDP and post-treatment CycloSam scintigraphy. Ratios of tumor uptake vs. contralateral normal bone ranged from 12.6–45.7. Two dogs experienced transient peritumoral swelling after injection. No dog experienced a dose-limiting hematologic toxicity.
Conclusions : CycloSam does not exhibit a saturation effect at dosages equivalent to those that would be administered to human beings for therapy with curative intent. The biodistribution and clearance of CycloSam is favorable for a bone-seeking, therapeutic radiopharmaceutical. Given the favorable toxicity profile, higher doses should be explored to maximize the therapeutic ratio for CycloSam, a novel skeletal targeted radiotherapeutic agent.
P03 A Case Report of Iodine-123 MIBG Uptake in Brown Adipose Tissue in a Pediatric Patient with Neuroblastoma Utilizing Hybrid SPECT/CT versus SPECT Imaging Alone.
John T. Doan, MD1, Jay S. Hiller, MD1, M. Leann Smith, MD1
1University of Oklahoma Health Sciences Center, College of Medicine, Department of Radiological Sciences, Oklahoma City, Oklahoma, USA.
Objective: The case report will describe unilateral iodine-123 MIBG uptake within brown adipose tissue (BAT) in the medial right shoulder/lower neck of a 7-year-old boy with neuroblastoma in the upper left thoracic paraspinous region, status post radiation therapy, tumor resection and left T1-T4 laminectomy, who presented with new onset of night sweats.
Methods: Physiologic evaluation for possible recurrence or metastatic disease utilizing iodine-123 MIBG with SPECT alone, followed by neck CT with contrast to evaluate for discrete mass, and subsequently iodine-123 MIBG with localization SPECT/CT to differentiate areas of abnormal uptake.
Results: Iodine-123 MIBG with SPECT revealed a focus of increased uptake in the medial right shoulder/lower neck, concerning for possible metastatic MIBG-avid tumor. Neck CT showed muscle edema within the right posterior paraspinous compartment with adjacent intermuscular fat stranding without discrete mass to identify a metastatic lesion. Subsequent iodine-123 MIBG imaging with localization SPECT/CT showed a band of uptake overlying fat density in the medial right shoulder/lower neck in a distribution most consistent with BAT. No evidence for recurrent/metastatic disease was identified.
Conclusions: The advantage of hybrid SPECT/CT over SPECT imaging alone is attributed to the more precise localization of anatomical lesion, allowing better characterization of abnormal and physiologic findings. In our patient, the application of hybrid SPECT/CT with iodine-123 MIBG imaging allowed us to differentiate between physiologic BAT versus metastatic disease.
The absence of BAT uptake in the contralateral side observed in our patient is consistent with few previously reported cases about the impact of sympathetic nerve damages causing inhibition of BAT uptake. The lack of BAT uptake seen in our patient with known neuroblastoma resection from the upper left thoracic paraspinous region, radiation therapy, and left T1-T4 laminectomy, was most likely caused by post -surgical and/or -radiation damage to the left sympathetic nerve chain.
P04 FDG PET in Nonparaneoplastic Autoimmune Limbic Encephalitis: Two Distinct Patterns of Brain Glucose Metabolism
Niraj R. Patel, MDi, Paul E. Schulz, MDii, Eugene Lai, MD, PhDiii, Ronald E. Fisher, MD, PhDiv
i Division of Nuclear Medicine (Department of Radiology), Baylor College of Medicine, Houston, Texas, USA; ii The University of Texas Health Science Center in Houston, The Mischer Neuroscience Institute, and The Memorial Hermann Hospital-TMC, Houston, Texas, USA; iii The Methodist Neurologic Institute, The Methodist Hospital, Houston, Texas, USA; iv Department of Radiology, The Methodist Hospital and Baylor College of Medicine, Houston, Texas, USA; Contact: NirajP@bcm.edu
Introduction: F-18 FDG PET is an established modality for distinguishing Alzheimer’s dementia (AD) from frontotemporal dementia and can help characterize the etiology of mild cognitive impairment.1 Classically, the FDG pattern of dementia with Lewy Bodies (DLB) overlaps significantly with that of AD, but with less sparing of the occipital cortex.2 DLB is universally progressive and irreversible. In a chart review, we discovered a patient with an FDG pattern consistent with advanced DLB who demonstrated partial reversibility on a follow-up PET scan. The patient’s clinical symptoms were also partially reversible.
Methods: Two sets of brain FDG PET scans obtained on the same PET/CT machine at the same institution approximately 10 months apart were reviewed as part of a systemic review of brain FDG PET images in patients diagnosed with autoimmune encephalitis. The clinical health record of the patient was also obtained and reviewed.
Results: An 80-year old male admitted to the institution for confusion and subacute cognitive decline had an initial brain FDG PET scan demonstrating moderate to marked decrease in frontal, temporoparietal and primary visual cortical FDG uptake with sparing of the sensorimotor cortices and subcortical structures. This FDG pattern is consistent with advanced DLB. Cognitive symptoms improved partially after IV corticosteroid treatment. The patient was rehospitalized after relapsing and diagnosed with non-paraneoplastic autoimmune limbic encephalitis. A second brain PET scan performed approximately 10 months after the first scan, after the patient responded to another short course of IV corticosteroid therapy, demonstrated improved FDG uptake in all cortical areas. The significant improvement in PET uptake ruled out an irreversible neurodegenerative disease as the etiology of the patient’s cognitive symptoms.
Conclusions: The classic FDG PET pattern of DLB does not always represent a neurodegenerative disorder, but can instead indicate a reversible disease such as autoimmune encephalitis.3
1. Foster NL, Heidebrink JL, Clark CM et al. FDG-PET improves accuracy in distinguishing frontotemporal dementia and Alzheimer’s disease. Brain 2007; 130 (10):2616–2635.
2. Silverman DHS. Brain 18F-FDG PET in the Diagnosis of Neurodegenerative Dementias: Comparison with Perfusion SPECT and with Clinical Evaluations Lacking Nuclear Imaging. JNM 2004; 45(4): 594–607.
3. Fisher RE, Patel NR, Lai EC, Schulz PE. Two Different F-18 FDG Brain PET Metabolic Patterns in Autoimmune Limbic Encephalitis. Clinical Nuclear Medicine 2012 (in press).
P05 Evaluation of Recurrent Prostate Cancer Utilizing PET/CT with 18F-FDG/18F-NaF Cocktail
Chiarra M. Thompson MD, Rosinda Delapena MD, and Irfan Farukhi MD
VA North Texas Health Care System, Dallas, Texas
Introduction: A combined 18F-NaF and 18F-FDG PET/CT is a potential method for detecting the site of recurrent disease in prostate cancer patients. This imaging modality may be better than conventional imaging for the workup of patients with recurrent prostate cancer.
Purpose: Identify an effective alternative method to stage and restage patients with prostate cancer using a combination of 18F-FDG and 18F-NaF in a single exam.
Discussion: Prostate cancer is malignancy that is estimated to effect as many as 80% of men who reach the age of 80. Prostate cancer may be detected by routine lab work or digital rectal examinations. Patients may be symptomatic but are commonly asymptomatic, particularly early in the disease process. Prostate cancer can be detected with imaging modalities such as ultrasound, CT, and MRI, but diagnosis is confirmed with biopsy. Most prostate cancers are indolent, yet a significant number of cancers have an aggressive histopathology. Staging may be completed with CT, Bone Scintigraphy, or Prostscint Imaging. After treatment, some patients have biochemical recurrence and the site of disease must be localized to guide therapy. It is often a challenge to find the site of recurrent/metastatic disease with conventional imaging modalities. Therefore, alternative methods of restaging recurrent prostate cancer would provide a significant clinical value, particularly at our institution where the patient population is predominantly male. Several patients with history of prostate cancer with biochemical recurrence were inducted into a study and completed both a Prostascint Scan and a combined 18F-NaF and 18F-FDG PET/CT. Images are being reviewed and compared. Thus far, both modalities have shown sites of abnormal tracer accumulation that was concerning for malignant/metastatic disease in multiple patients. When disease was present on both modalities, the lesions were more conspicuous on PET imaging and were identified with more confidence.
Conclusion: PET/CT cocktail could be a viable method of detection of recurrent disease.