Molecular Imaging in Cancer

Chaitanya Divgi, MDProfessor of Radiology & Radiation Oncology

Chief, Nuclear Medicine & Clinical Molecular ImagingDepartment of RadiologyUniversity of Pennsylvania

chaitanya.divgi@uphs.upenn.edu

OverviewMolecular Imaging is critical to cancer patient management:

•Diagnosis may be made earlier and more accurately•The extent and location of the disease

may be more accurately estimated, before and after treatment.•Treatments may be better selected, and

unnecessary procedures avoided.•The effect of treatment, and the severity

of the disease, may be better assessed.

Positron Emission Tomography (PET)

• PET revolutionized functional imaging by providing exquisite snap-shots

• 18FDG PET/CT standard of care for staging disease and response evaluation

• May be the best indicator for recurrent disease

PET and PET/CT

• Medicare and CMS has approved the use of FDG PET/CT for a variety of cancers.

• A recent study showed that imaging with FDG PET/CT could affect patient care significantly in about a third of patients with cancer.

Tumor definition by PET

Vander wel et al. Int J Radiat Oncol Biol Phys. 2005; 61: 649-55.

Cachin, F. et al. J Clin Oncol; 24:3026-3031 2006

Guide therapy by evaluation of metabolic response

Staging for therapy

• Staging with PET/CT is superior to either modality alone

Response to therapy

Esophageal cancer

Response to Hormonal Therapy

Pre-Rx Post-Rx

FES FDG FDG• Newly Dx’d met breast CA

• ER+ primary

• FES-negative bone mets

University of Washington

• Recurrent sternal lesion

• ER+ primary

• Recurrent Dz strongly FES+

Example 1

Example 2

(Linden, J Clin Onc, 2006)

Surgery may be avoided or tailored based on tumor characteristics

Divgi et al, Lancet Oncol. 2007; 8 : 304-10.

Response evaluation by PET

Changes in tumor characteristics precede structural change and predict overall therapeutic outcome

Thank you.