PET/CT in Oncology George Segall, M.D. Stanford University

Evolution of Technology CT PET/CT PET 2001 1973 2000 3

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Imaging Protocol Patient CT PET - Inject tracer - Fast 4 hrs prior to exam - Inject tracer - Start scan 60 min later CT - Topogram (scout) - CT scan (1 min) PET - Brain (10 min) - Heart (10 min) - Body (20 min) <130

PET Tracer: FDG Glucose FDG Glucose-6-P FDG-6-P Plasma Cell 18F-fluorodeoxyglucose (FDG) is taken up by cells proportionate to their metabolic rates

PET CT PET/CT CT (1 min) FDG Bed 15 mCi 1 min KVs mAs Slice 130 kV 5 mm H.S., 077-64-28

What Are the Advantages of PET/CT? Advantages of CT • high spatial resolution Advantages of PET • better lesion characterization • enhanced lesion detection

Applications of PET-CT Brain 5% Heart 5% • epilepsy • perfusion • tumor • viability Body 90% 76% • dementia 1.5 million exams performed annually • tumor • infection • bone 3

PET - CT in Tumor Imaging • Detect radiographically occult lesions • Characterize radiographic abnormalities • Evaluate extent of disease • Evaluate response to therapy 3

Normal PET - CT Body Scan 3

Normal PET/CT scan CT PET/CT PET

Abnormal PET - CT Body Scan 3

Medicare Approved Indications for PET-CT Diagnosis, Staging, and Restaging (unless otherwise indicated) • Head & Neck • Thyroid • Breast • Lung • Esophagus • Colon & Rectum • Cervix • Lymphoma • Melanoma • Other Cancers follicular: I -131 neg, Tg >10 ng/dL not breast masses or regional nodes only non-small cell Medicare approved indications for PET include 9 cancers. PET is approved for diagnosis, staging, and restaging in most cases, with a few notable exceptions. CT/MRI neg for extra-pelvic mets not regional nodes when enrolled in NOPR 3

National Oncologic PET Registry http://www.cancerpetregistry.org Sponsored by AMI and managed by ACR for CMS April 15, 2008 1,728 facilities - 74,541 scans since May 2006

National Oncologic PET Registry http://www.cancerpetregistry.org Pre PET/CT Form • Indication for PET/CT • Cancer type and extent • Management plan Post PET/CT Form • Change in assessment of extent of disease • Change in management plan

National Comprehensive Cancer Network www.nccn.org The National Comprehensive Cancer Network is a consortium of 19 U.S. cancer centers that meet regularly to make evidence based recommendations on cancer diagnosis, staging, and treatment.

Practice Guidelines in Oncology National Comprehensive Cancer Network Practice Guidelines in Oncology Acute Myeloid Leukemia Bladder Cancer Bone Cancer Breast Cancer Central Nervous System Tumors Cervical Cancer Chronic Myelogenous Leukemia Colorectal Cancer Esophageal Cancer Gastric Cancer Head and Neck Cancer Hepatobiliary Cancer Hodgkin’s Disease Kidney Cancer Melanoma Myelodysplastic Syndromes Multiple Myeloma Neuroendocrine Tumors Non Hodgkin’s Lymphoma Non-Small Cell Lung Cancer Occult Primary Cancer Ovarian Cancer Pancreatic Cancer Prostate Cancer Soft Tissue Sarcoma Skin Cancer (except Melanoma) Small Cell Lung Cancer Testicular Cancer Thyroid Cancer Uterine Cancer The NCCN publishes practice guidelines for 30 types of cancer. These guidelines are available at www.nccn.org

Practice Guidelines in Oncology National Comprehensive Cancer Network Practice Guidelines in Oncology Bone Cancer Breast Cancer Cervical Cancer Colorectal Cancer Esophageal Cancer Head and Neck Cancer Hodgkin’s Disease Melanoma Multiple Myeloma Non Hodgkin’s Lymphoma Non-Small Cell Lung Cancer Occult Primary Cancer Ovarian Cancer Soft Tissue Sarcoma Small Cell Lung Cancer Testicular Cancer Thyroid Cancer Cancers in which PET/CT is recommended.

Lesion Characterization T7823. 47 y/o man incidentally discovered lung nodule following MVA 12/20/05. PET on 1/9/06 showed high FDG uptake. Thoracotomy on 2/24/06, frozen section showed no cancer, so patient had a wedge resection. Final path report showed poorly differentiated lung cancer, so patient had a left upper lobectomy on 3/6/06. 47 year old man with multiple trauma from a MVA who was incidentally discovered to have a pulmonary nodule 3

Lesion Characterization V9153. 84 year old man with chronic cough. CXR on 6/10/05 showed a pulmonary nodule. CT on 7/16/05 showed a 13 mm nodule in the LLL with subtle rim calcification. No change on CXR done 11/22/05. PET on 12/12/05 was negative. No further imaging as of 3/28/06. 84 year old man with chronic cough found to have a 13 mm nodule on CXR 3

Enhanced Detection 73 year-old woman who had a hemi-colectomy for colon cancer. Her CEA level began to rise post-operatively. She had CT, but intravenous contrast could not be used because her creatinine level was elevated. CT was normal, but PET showed a solitary hypermetabolic focus in the left lobe of the liver. The patient had a laporotomy and wedge resection based on the PET findings. Pathological examination confirmed metastatic colon cancer. 73 year old woman s/p resection for colon cancer, rising CEA level and negative CT

Enhanced Detection H6636. CT (VA Fresno 5/2008) PET/CT 6/20/2008

Enhanced Detection 70 y/o male with H&N cancer

Enhanced Detection I-131 FDG PET 47 year old man who had biopsy proven recurrent thyroid cancer 3 months after thyroidectomy. The PET scan shows multiple hypermetabolic lymph nodes in the right neck and supraclavicular region, which were not visible with radioiodine. I-131 FDG PET 47 year old man with biopsy proven recurrent thyroid cancer 3 months after thyroidectomy

Unknown Primary 68 year old man who presented with right neck mass E1638. PET/CT 10/17/07. 68 year old man who presented with right neck mass

Staging 49 year old man with new lung cancer 49 year-old man with newly diagnosed lung cancer. CT of the thorax showed a mass in the upper lobe of the upper lobe of the left lung. There was no sign of metastatic disease. PET showed the primary tumor, as well as a hypermetabolic mass in the pelvis. Fused transaxial PET-CT images showed probable metastatic disease behind the left psoas muscle. CT with IV contrast was subsequently performed, and showed an enhancing mass in the same area. The patient developed additional distant metastases and died a few months later. 49 year old man with new lung cancer

Recurrent Disease 64 year old man s/p laryngectomy, now has dysphagia M6736. PET/CT 9/25/07. 64 year old man s/p laryngectomy, now has dysphagia

Monitoring Response H5493. PET/CT before chemotherapy 7/24/07; after chemotherapy 11/1/07 63 year old man stage 3A lung cancer, has received 4 cycles of chemotherapy

CT + PET/CT vs PET/ CT MOST CASES • Standard CT followed by PET/CT if needed SOME CASES • PET/CT CT component can be low resolution or optimized

Problems and Pitfalls • False negative findings Tumor histology Lesions smaller than 8 mm Diabetes/Non-fasting patients • False positive findings Normal physiology Granulomas and other infections Adenomas

Standard CT PET/CT D1693. PET/CT 5/24/07. 56 year man with HCV, end stage liver disease, and presumed hepatoma

Physiologic Uptake: Brown Fat

Infection 68 year old man with solitary lung nodule. Biopsy: aspergillosis 3

Granulomatous Disease A8665. PET/CT 6/6/07. 62 year old man with hilar and mediastinal adenopathy. Biopsy: sarcoidosis

Adenoma 82 year old man with wt loss and liver masses L0918. PET/CT 9/11/07. 82 year old man with wt loss and liver masses

Adenoma 82 year old man with wt loss and liver masses L0918. PET/CT 9/11/07. 82 year old man with wt loss and liver masses

Clinical Impact of PET/CT • More accurate diagnosis • Avoidance of unnecessary tests, and (potentially) harmful procedures • Better treatment or management

National Oncologic PET Registry http://www.cancerpetregistry.org 36.5% change in decision to treat or not treat

Conclusions 1. CT is the first imaging test of choice in most cases 2. PET - CT is more accurate than CT alone • Characterizing lesions difficult to biopsy • Detecting occult cancer • Determining extent of cancer and response to therapy 3. PET - CT changes management 36%

Why PET-CT?