CT 18 FFDG PET Luso della PET nella

CT [18 F]FDG PET L'uso della PET nella diagnosi precoce e la valutazione del SUV come indicatore di prognosi Gino Pepe Medicina Nucleare – PET H. San. Raffaele IRCCS - Milano

[18 F]FDG-PET

Why [18 F]FDG-PET in tumors?

Why [18 F]FDG-PET in tumors? Elevated glucose metabolism in tumor

Why [18 F]FDG-PET in tumors? Elevated glucose metabolism in tumor [18 F]FDG is a glucose analog

Why [18 F]FDG-PET in tumors? Elevated glucose metabolism in tumor [18 F]FDG is a glucose analog [18 F]FDG uptake into viable neoplastic cells

[18 F]FDG PET: APPLICATION IN LUNG CANCER Differentiating benign from malignant lesions (SPN) Staging N and M and re-staging for therapy planning Predicting and monitoring response to therapy

Solitary Pulmonary Nodule (SPN) Solitary lung lesion < 3 cm in diameter 20% - 40% of SPN are malignant Initial presentation in 20% - 30% of lung cancer Coleman et al. J Nuc Med 1999

[18 F]FDG PET Measure of metabolic activity of SPN Visual Analysis Quantitative analysis CT [18 F]FDG PET SUV = 7. 3

[18 F]FDG PET Measure of metabolic activity of SPN Visual Analysis: nodule activity vs mediastinal blood pool activity Quantitative analysis CT [18 F]FDG PET SUV = 7. 3

[18 F]FDG PET Measure of metabolic activity of SPN Visual Analysis: nodule activity vs mediastinal blood pool activity Quantitative analysis CT [18 F]FDG PET SUV = 7. 3

[18 F]FDG PET Measure of metabolic activity of SPN Visual Analysis Quantitative analysis: SUV (standardized uptake value) CT [18 F]FDG PET SUV = 7. 3

Standardized Uptake Value = SUV – SUVBW = Ct/(ID/BW) = (k. Bq/ml) / (MBq/Kg) – SUVLBM = Ct/(ID/LBM) = (k. Bq/ml) / (MBq/Kg) • LBM uomini =1. 1 * W - 128 *(W/h)2 • LBM donne = 1. 07 * W - 148 *(W/h)2 – SUVBSA = Ct/(ID/BSA) = (k. Bq/ml) / (MBq/m 2) • BSA = 0. 007184 * W 0. 425 * h 0. 725

[18 F]FDG PET Measure of metabolic activity of SPN Visual Analysis Quantitative analysis: SUV (standardized uptake value) CT [18 F]FDG PET SUV = 7. 3

[18 F]FDG PET Measure of metabolic activity of SPN Visual Analysis Quantitative analysis: SUV (standardized uptake value) CT [18 F]FDG PET SUV = 7. 9 7. 3

[18 F]FDG PET Lung cancer is hypermetabolic A SPN with SUV more than 2. 5 is considered to be malignant No difference between visual vs. quantitative analysis Visual SUV Sens Spec PPV NPV Acc 100 69 90 100 92 96 69 90 85 89 Hain SF et al. Eur J Nucl Med 2001

CT [18 F]FDG PET Fused SPN: 1. 2 cm in diameter HSR - Milano

CT [18 F]FDG PET CT- PET SPN: 1. 4 cm in diameter HSR - Milano

Accuracy of PET with [18 F]FDG in SPN or Pulmonary Opacity Authors Sensitivity Duhaylongsod (1995) Specificity Accuracy 97% 82% 92% Bury (1996) 100% 88% 96% Lowe (1998) 98% 69% 89% Prauer (1998) 90% 83% 87% Graeber (1999) 97% 89% 92% Hung (2001) 95% 50% 86% Hellwig (2001) (meta-analysis) 96% 80% - Gould (2001) (meta-analysis) 97% 78% - Hickeson (2002) (using PET-CT) 97% 82% 92%

Limitations of FDG-PET for Lung Nodule Characterization: False-positive results Inflammatory lesions (mainly granulomas) Tubercolosis Histoplasmosis Sarcoidosis Cryptococcosis Aspergillosis

Limitations of FDG-PET for Lung Nodule Characterization: False-negative results Lesion Dimension Histological Type Hyperglycemia Small lesion < 5 -6 mm % of viable neoplastic cells in SPN

CT [18 F]FDG PET ? Fused R. F. 53 aa Lung nodule 4 mm in diameter HSR - Milano

CT [18 F]FDG PET CT- PET Z. A. 41 aa SPN: 4 mm in diameter HSR - Milano

Limitations of FDG-PET for Lung Nodule Characterization: False-negative results Lesion Dimension Carcinoid Histological Type Pure Bronchioloalveolar Carcinoma (BAC), mucinous ca, neuroendocrine tumor Hyperglycemia Well differentiated type

CT [18 F]FDG PET CARCINOID HSR - Milano

CT [18 F]FDG PET/CT P. G. 68 aa SPN: 10 mm in diameter Well differentiated tumor HSR - Milano

[18 F]FDG PET IN LUNG CANCER SUV and histological type Mean SUV BAC (12) 1. 3 Well Differentiated (10) 3. 1 Moderately differentiated (12) 4. 3 Poorly differentiated (4) 5. 6 Higashi et al. Nucl Med Comm 2000

[18 F]FDG PET IN LUNG CANCER FDG uptake in BAC No [18 F]FDG uptake in more than 50% of patients with BAC 85, 7% of BAC are negative for Glut-1 (glucose transporter) expression (Higashi 2000) [18 F]FDG-PET FN A different PET tracer may solve the problem

Pure Bronchioloalveolar Carcinoma CT 18 F]FDG PET [11[C]Choline PET SUV = 1. 73 B. A. 65 aa HSR Milano

Limitations of FDG-PET for Lung Nodule Characterization: False-negative results Lesion Dimension Histological Type Hyperglycemia > 200 mg/dl = PET not performed

VALUTAZIONE DELLA RISPOSTA ALLA TERAPIA con PET e [18 F]FDG NEL TUMORE POLMONARE 113 pazienti con neoplasia polmonare NSC trattati con chemio o radiochemioterapia Differenza significativa nella sopravvivenza tra pazienti con PET positiva e pazienti con PET negativa Mediana di sopravvivenza 12. 1 mesi nei pz con PET + dopo terapia 34. 2 mesi nell’ 85% dei pz con PET - dopo terapia Patz et al AJR, 2000

FDG-PET: VALUTAZIONE PRECOCE DELLA RISPOSTA ALLA CHEMIOTERAPIA 57 pazienti in stadio IIIB o IV studiati con PET prima e dopo I° ciclo di chemio PET Responder ( SUV – 61%) PR in 20/28 PET responders (71%) SD o PD in 26/27 PET non responders (96%) Weber et al. , J Clin Oncol 2003; 21: 2651

PET in SPN • Who: – Patient with indetermined lung nodule • When: – After a CT study • Why: – Metabolic characterization of indetermined lung nodule (benign vs malignant)