Anca M Avram

Publications (41) View all

• Source

  Available from: Anca M Avram

  Article: Preablation 131-I Scans With SPECT/CT in Postoperative Thyroid Cancer Patients: What Is the Impact on Staging?

  Anca M Avram, Lorraine M Fig, Kirk A Frey, Milton D Gross, Ka Kit Wong
  [show abstract] [hide abstract]
  ABSTRACT: Context: The utility of preablation radioiodine scans for the management of differentiated thyroid cancer remains controversial. Objective: To determine the contribution of preablation Iodine 131 (131-I) planar with single-photon emission computed tomography/computed tomography (SPECT/CT; diagnostic [Dx] scans) to differentiated thyroid cancer staging. Design: Prospective sequential series at university clinic. Methods: Using American Joint Committee on Cancer (AJCC) tumor, node, metastasis (TNM) staging, seventh edition 320 patients post-total thyroidectomy were initially staged based on clinical and pathology data (pTN) and then restaged after imaging (TNM). The impact of Dx scans with SPECT/CT on N and M scores, and TNM stage, was assessed in younger, age <45 years, n = 138 (43%), and older, age ≥45 years, n = 182 (57%) patients, with subgroup analysis for T1a and T1b tumors. Results: In younger patients Dx scans detected distant metastases in 5 of 138 patients (4%), and nodal metastases in 61 of 138 patients (44%), including unsuspected nodal metastases in 24 of 63 (38%) patients initially assigned pathologic (p) N0 or pNx. In older patients distant metastases were detected in 18 of 182 patients (10%), and nodal metastases in 51 of 182 patients (28%), including unsuspected nodal metastases in 26 of 108 (24%) patients initially assigned pN0 or pNx. Dx scans detected distant metastases in 2 of 49 (4%) T1a, and 3 of 67 (4.5%) T1b patients. Conclusions: Dx scans detected regional metastases in 35% of patients, and distant metastases in 8% of patients. Information acquired with Dx scans changed staging in 4% of younger, and 25% of older patients. Preablation scans with SPECT/CT contribute to staging of thyroid cancer. Identification of regional and distant metastases prior to radioiodine therapy has significant potential to alter patient management.
  The Journal of clinical endocrinology and metabolism 03/2013; 98(3):1163-71. · 6.50 Impact Factor
• Source

  Available from: Anca M Avram

  Article: SPECT/CT Evaluation of Unusual Physiologic Radioiodine Biodistributions: Pearls and Pitfalls in Image Interpretation.

  Daniel I Glazer, Richard K J Brown, Ka Kit Wong, Hatice Savas, Milton D Gross, Anca M Avram
  [show abstract] [hide abstract]
  ABSTRACT: Radioiodine imaging has a well-established role in depicting metastatic disease after thyroidectomy in patients with well-differentiated thyroid cancer. Uptake of radioiodine in thyroid metastases depends on expression of sodium-iodide symporter (NIS) by tumor tissues. However, because radioiodine may also accumulate in normal structures and tissues, it is important to distinguish physiologic radioiodine activity from metastatic disease. Furthermore, secretions that contain radioiodine may also simulate pathologic uptake. A spectrum of physiologic distributions, normal variants, and benign mimics of disease have been described in the literature; yet, even when armed with a comprehensive knowledge of these patterns, interpreting radiologists and nuclear physicians may still encounter diagnostic uncertainty. Single-photon emission computed tomography (SPECT) with integrated computed tomography (CT) is a novel technology that, when applied to diagnostic iodine 123 or iodine 131 (I) radioiodine scintigraphy, may accurately localize and help distinguish benign mimics of disease, with the potential to alter the management plan. SPECT/CT is increasingly being used with radioiodine scintigraphy to evaluate patients with thyroid cancer and shows promise for improving imaging specificity and reducing false-positive results. © RSNA, 2013.
  Radiographics 03/2013; 33(2):397-418. · 2.85 Impact Factor
• Source

  Available from: Anca M Avram

  Article: Prediction of therapy tumor-absorbed dose estimates in I-131 radioimmunotherapy using tracer data via a mixed-model fit to time activity.

  Matthew J Schipper, Kenneth F Koral, Anca M Avram, Mark S Kaminski, Yuni K Dewaraja
  [show abstract] [hide abstract]
  ABSTRACT: Abstract Background: For individualized treatment planning in radioimmunotherapy (RIT), correlations must be established between tracer-predicted and therapy-delivered absorbed doses. The focus of this work was to investigate this correlation for tumors. Methods: The study analyzed 57 tumors in 19 follicular lymphoma patients treated with I-131 tositumomab and imaged with SPECT/CT multiple times after tracer and therapy administrations. Instead of the typical least-squares fit to a single tumor's measured time-activity data, estimation was accomplished via a biexponential mixed model in which the curves from multiple subjects were jointly estimated. The tumor-absorbed dose estimates were determined by patient-specific Monte Carlo calculation. Results: The mixed model gave realistic tumor time-activity fits that showed the expected uptake and clearance phases even with noisy data or missing time points. Correlation between tracer and therapy tumor-residence times (r=0.98; p<0.0001) and correlation between tracer-predicted and therapy-delivered mean tumor-absorbed doses (r=0.86; p<0.0001) were very high. The predicted and delivered absorbed doses were within±25% (or within±75 cGy) for 80% of tumors. Conclusions: The mixed-model approach is feasible for fitting tumor time-activity data in RIT treatment planning when individual least-squares fitting is not possible due to inadequate sampling points. The good correlation between predicted and delivered tumor doses demonstrates the potential of using a pretherapy tracer study for tumor dosimetry-based treatment planning in RIT.
  Cancer Biotherapy & Radiopharmaceuticals 09/2012; 27(7):403-11. · 1.44 Impact Factor
• Source

  Available from: Anca M Avram

  Article: Three endocrine neoplasms: an unusual combination of pheochromocytoma, pituitary adenoma, and papillary thyroid carcinoma.

  James C Sisson, Thomas J Giordano, Anca M Avram
  [show abstract] [hide abstract]
  ABSTRACT: Three endocrine neoplasms-bilateral pheochromocytomas, somatotrophic pituitary adenoma inducing acromegaly, and papillary carcinoma of the thyroid-occurred concurrently in a patient. A genetic mutation was hypothesized. Possible previously described genetic mutations were explored. Clinical assessments, laboratory data, images of tumors, histopathology, and immunohistochemistry of excised tissues documented the three neoplasms. Clinical assessment of the patient, family history, and a review of the literature sought a familial basis for the disorders. The methods confirmed the presence of three endocrine neoplasms. Each neoplasm was surgically excised and histologically verified. Surgical and (131)I treatments reduced the papillary carcinoma, but eventually this tumor progressed to a lethal degree. History, including that of nine siblings, uncovered no familial neoplasms. No similar case was found in the literature, but possible associations with germline mutations were considered. The concurrent development of pheochromocytomas, pituitary somatotrophic adenoma, and papillary thyroid carcinoma appears to be unique. Nevertheless, such tumors, particularly bilateral pheochromocytomas, strongly suggest a de novo germline mutation in a gene not previously associated with multiple endocrine neoplasia syndromes.
  Thyroid: official journal of the American Thyroid Association 03/2012; 22(4):430-6. · 2.60 Impact Factor
• Chapter: Functional Imaging of Adrenocortical Carcinoma

  Anca M. Avram, Stephanie Hahner
  [show abstract] [hide abstract]
  ABSTRACT: Increased glucose metabolism through the activation of aerobic glycolysis is a central feature of malignant transformation and progression (the Warburg effect) [1]. Malignant tumors can be detected with high sensitivity and specificity by imaging their increased metabolic rate for glucose; and positron emission tomography (PET) using the glucose analog fluorine-18 labeled fluoro-deoxyglucose ([18F]-FDG) has become a routine clinical imaging strategy for staging and restaging most solid tumors. In recent years, metabolic imaging has been increasingly combined with computed tomography (CT) imaging for precise anatomic localization resulting in fusion PET-CT. After intravenous injection [18F]-FDG is transported across cell membrane by sodium-independent, facilitative glucose transporters (GLUTs), and in most malignant tumors GLUT1 is frequently highly expressed. Intracellularly, [18F]-FDG is phosphorylated by hexokinase to [18F]-FDG-6 phosphate, which cannot be further metabolized in the glycolytic pathway and becomes trapped within the cell steadily accumulating in metabolically active cells [2]. This process has enabled accurate metabolic imaging of malignant tumors based on their increased rate of metabolism and glucose utilization as compared to surrounding normal tissues.
  12/2010: pages 85-103;