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© 2004 Cardinal Health. All rights reserved. PET/CT: PET/CT: Improved Improved Confidence in Confidence in Imaging Imaging ?

© 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

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Page 1: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

PET/CT: PET/CT: Improved Confidence Improved Confidence

in Imagingin Imaging

?

Page 2: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Why PET/CTWhy PET/CT

• Improved diagnostic accuracy over PET or CT alone

More Accurate Disease StagingMore Accurate Surgical PlanningMore Accurate Guided BiopsyMore Accurate Radiation Therapy Planning

• IMPROVED DIAGNOSTIC CONFIDENCE(for improved patient management)

Page 3: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

History of Radiology and CancerHistory of Radiology and Cancer

• Form = Anatomy

• Anatomy continues to be the cornerstone of cancer imaging for diagnosis, staging and follow up.

• Form has served us very well in X-Ray, US, CT, and MR

“50 Years of Imaging Form”

MR

CT

Page 4: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

““Form” Strengths and Limitations Form” Strengths and Limitations

Strengths …but Diagnostic Questions Remain

Clear delineation of form What is normal? Performance is less post operative due to distortionof normal anatomy

Accurate detection and What is the mass? (fat? water? air?)localization of masses

Accurate detection of lymph What is within the lymph nodes? nodes (present or absent) (benign or malignant?)

Some small lesion What is the cause?identification

Have small tumor foci been over-looked (especially if surrounded by

normal tissues)?

Page 5: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

““Form” Strengths and Limitations Form” Strengths and Limitations

Treatment Planning Questions Also Remain

What will be the response to a particular therapy?

What sort of tumor biology is present?

Has there been a response (especially cytostatic) that I’m not seeing yet because it’s too soon for the “form” to reflect changes?

PET (and PET/CT) address many of the limitationsof anatomic imaging alone

Page 6: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

““Function” Imaging – FDG-PET Function” Imaging – FDG-PET

FDG-PET Strengths …but

High sensitivity for detection of abnormal cell metabolism

Real-time measurements of changes in disease state (and hence effectiveness of therapy)

Powerful rotating display formats to aid in accurate interpretations based on human motion-oriented vision

Page 7: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

““Function” Imaging – FDG-PET Function” Imaging – FDG-PET

…but Questions Remain

Where is the tracer uptake?

Where should we biopsy?

Where should we resect?

Is the tracer uptake in tumor or non-malignant tissues (e.g. infection)?

Page 8: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

PET shows modest basilar lung FDG

uptake?

CT shows infiltrates at both lung bases.

Clearly abnormal.

Tough QuestionsTough Questions

What is it?

Page 9: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

What is PET/CT? What is PET/CT?

Where Form meets Function

• A view into the body that allows us to see what it is happening and where.

• Hybrid Imaging Device/Modality Diagnostic CT scanner (high

quality images of anatomy) PET scanner (high quality

images of function) Computer and software to

fuse/display images

• No patient motion between studies (or very little)

Page 10: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

What is PET/CT? What is PET/CT?

Where Form meets Function

The best of detection and localization

Better than PET or CT alone

lung cancer

normal heart

Page 11: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

More Accurate StagingMore Accurate Staging

PET/CT

• Sensitivity to hyper-metabolism in normal-sized nodes on CT.

• Accurate spatial localization of abnormalities detected on PET, but difficult to localize.

Page 12: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

More Accurate StagingMore Accurate Staging

• No enlarged lymph nodes seen in the apex of the thorax on CT.

• Focal area of increased radionuclide uptake found on PET. Exact location remained unclear.

• PET/CT fused image matched hyper-metabolism to a normal-sized lymph node.

• Metastatic disease confirmed via histology.

• Chemotherapy initiated.

Lardinois, et. al., NEJM 2003, 348:2500-07.

5mm lymph node met

NSCLC

Page 13: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

More Accurate StagingMore Accurate Staging

• Breast cancer patient

• Malignant cell activity localized in a normal sized axillary lymph node.

• Disease overlooked on CT alone. Hao Vuong, MD,

Baptist Hospital of Miami

Page 14: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

More Accurate Surgical PlanningMore Accurate Surgical Planning

• Colorectal cancer patient

• PET/CT demonstrates a solitary met in the liver

• Upstages patient to Stage IV

• Despite Stage IV, PET/CT indicates there is still a possibility of surgical cure, based on the localization of primary and metastatic activity.

Hao Vuong, MD, Baptist Hospital of Miami

Page 15: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

More Accurate Guided BiopsyMore Accurate Guided Biopsy

• CT shows LUL mass consistent with Lung Cancer and no nodal metastases

• PET shows right paratracheal uptake suggesting nodal metastasis

• PET/CT shows metastasis to normal sized right paratracheal node

• Proven by biopsy.

Page 16: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

More Accurate Guided BiopsyMore Accurate Guided Biopsy

• Head and Neck cancer patient

• PET/CT identifies a nasopharyngeal squamous cell carcinoma

• Confirms increased metabolic activity is localized in a bilateral lymph node.

• Patient therapy plan is changed from limited-field radiation treatment to a combined radiation/chemotherapeutic approach.

Page 17: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

More Accurate RT PlanningMore Accurate RT Planning

• PET/CT is performed on a radiation therapy table to ensure consistent patient positioning.

• Fiducial markers are evident in the images.

• PET/CT images can be moved directly into radiation therapy planning workstations for seamless integreation of metabolic, anatomic, and irradiation planning information.

Page 18: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

More Accurate RT PlanningMore Accurate RT Planning

History • 63 YOF, nasopharyngeal cancer 5 yrs prior• Presents with progressive dysphagia and neck pain• Panendoscopy negative, MRI unrevealing

PET/CT Findings• FDG accumulation in the posterior aspect of the larynx

(SUV= 15.8) – not shown here• Small focus with mild FDG uptake (SUV = 1.2)

corresponding to a small lymph node in the left neck.

Impact to Patient Management• Deep biopsies confirmed squamous cell carcinoma, likely

the development of a second primary head and neck cancer. • Mild FDG uptake in the small node is likely to be

metastatic. • Radiation therapy was selected as the primary treatment.

The PET/CT images were used in planning the radiation therapy.

SUV = 1.2

Page 19: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

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Improved ConfidenceImproved Confidence

• CT is clearly abnormal

• PET is mildly abnormal

• When combined: Worrisome for brochioloalveolar carcinoma

• Confirmed by biopsy

Bronchioloalveolar CarcinomaBronchioloalveolar Carcinoma

Page 20: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

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Characterization and Localization Characterization and Localization

• CT shows precise lesion size, shape and location

• PET shows increased FDG uptake

• Non-Small-Cell Lung Cancer

Page 21: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Confirmation of Benign NoduleConfirmation of Benign Nodule

• CT shows pulmonary nodule which is large enough to image with PET

• PET shows no increased tracer uptake

• No disease present

Page 22: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Better than PET or CT aloneBetter than PET or CT alone

Diagnostic Accuracy with Respect to Tumor Stage (40 Pts)Non-Small-Cell Lung Cancer

Classification Correct

butImaging Method Correct Equivocal Incorrect

CT alone 58% 20% 22%

PET alone 40% 40% 20%

Visual correlation of 65% 12% 22%PET and CT

Integrated PET-CT 88% 10% 2%Lardinois, et. al., NEJM 2003, 348:2500-07

Page 23: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Better than PET or CT aloneBetter than PET or CT alone

Diagnostic Accuracy with Respect to Node Stage (37 Pts)Non-Small-Cell Lung Cancer

Classification Correct

butImaging Method Correct Equivocal Incorrect

CT alone 59% 5% 35%

PET alone 49% 38% 14%

Visual correlation of 59% 11% 30%PET and CT

Integrated PET-CT 81% 3% 16%Lardinois, et. al., NEJM 2003, 348:2500-07

Page 24: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Improved CertaintyImproved Certainty

What is Tumor? What is Not?

History of Melanoma

Page 25: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Normal Tissues with FDG UptakeNormal Tissues with FDG Uptake

• Not everything using glucose is tumor.

• Anatomy can be helpful in making this separation.

Example: Normal Head and Neck areas of increased FDG metabolism(Minimize by NOT talking during uptake nor swallowing)

TonsilsSubmandibular and Parotid GlandsCricoarytenoid muscles

Page 26: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Parotids, Soft Palate, Spinal Cord

Normal FDG-PET MapNormal FDG-PET Map

Page 27: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

PET/CT: Faster Scan TimePET/CT: Faster Scan Time

• Much faster total scan time than PET alone (approx 20 minutes)

CT provides 30 second transmission scans for the PET study vs 20 minute transmission scans with PET only devices

40-50% increased scan volume capacity

Improved cost-effectiveness with improved productivity

20 min emission 20 min transmission

20 min emission

20 sec transmission

PET Only

PET/CT

40 min

20 min

Page 28: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Patient preparationPatient preparation

• Fasting for four hours

• Patient changed into gown and pants

• All metallic objects are removed

• Check glucose levels

< 200 mg/dl

• 2 bottles of Readi-CAT (Barium sulphate 1.3 %) oral CT contrast prior to injection of 18F-FDG

Page 29: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Patient PreparationPatient Preparation

PET Scan Preparation

• Fasting for 4 hours

• Patient changed into gown and pants

• All metallic objects are removed

• Check glucose levels (< 200 mg/dl)

• .22 mCi/kg FDG for whole body imaging (injected dose varies by scanner)

• 2D or 3D imaging of whole body (3D imaging of brain)

CT Scan Preparation

• Patient is positioned head first and supine on the table

• Scanning begins from meatus of ear to mid thigh

• Shallow breathing during the CT

• Currently, non contrast CT is best choice for transmission images as arterial contrast can cause artifacts

Page 30: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Scan ProtocolsScan Protocols

PET Scan Protocol

• 3-5 minute emission per FOV for Whole Body imaging

• 3 minute emission per FOV for Melanoma imaging (more FOVs)

• 10-20 minute emission for 3D brain imaging

CT Scan Protocol

• Helical

• High Speed

• Pitch 6

• 22.5 mm/rotation

• 5 mm slices

• 140 kV & 80mA—varies

• 50 cm DFOV

• 512 x 512 matrix

Page 31: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

PET/CT (Fusion) WorkstationsPET/CT (Fusion) Workstations

• Fusion occurs on the PET/CT scanner workstation

• Hi-Res CT images are minimized to 128x128 matrix

• Images can be displayed in any plane or slice

• MIP (3D PET images) and CT Scout views are provided

Page 32: © 2004 Cardinal Health. All rights reserved. PET/CT: Improved Confidence in Imaging ?

© 2004 Cardinal Health. All rights reserved.

Where Form meets FunctionWhere Form meets Function

PET is Very Accurate.PET/CT is even more Accurate.

Disease Staging Surgical Planning Guided Biopsy Radiation Therapy

Planning

PET/CTBetter than PET or CT alone

Editor: Richard L. Wahl, M.D.Division of Nuclear MedicineDepartment of RadiologyJohns Hopkins Medical Institutes

Other Contributors:Hao VuongBaptist Hospital of Miami

Jack ZifferBaptist Hospital of Miami

Homer MacapinlacMD Anderson Cancer Center