PEM - Positron Emission Mammography

Positron Imaging Products (PIP), a subsidiary of IPT is the exclusive Canadian distributor of Naviscan's PET Mammography (PEM) scanner. Below is some background information on PEM and Naviscan.

PEM Background

PEM is a nuclear medicine exam which uses intravenous injectable FDG, (fluoro-deoxyglucose), a glucose analog, which accumulates in glucose avid cells. FDG will accumulate in both inflammatory and cancerous states as they have higher metabolic rate than normal cells. This glucose analog is phosphorylated but does not proceed through the entire cellular energy production cycle or Krebs cycle so it maintains its presence within the cell which permits image acquisition.

Tissue Diagnosis:
Ductal Carcinoma In Situ and Invasive Ductal Carcinoma

X-Ray	PEM Flex™	Whole Body PET	X-Ray CT

Following a 4 hour fast, serum blood is drawn to determine blood glucose level. 10mCi FDG is injected intravenously and imaging is acquired one hour later. Imaging is obtained on the dedicated breast PET in a manner similar to mammography. The PEM detectors are mounted on the 2 compression paddles. 1000 luteitium photodetecting crystals are present on each detector. The breast is imaged, similar to mammography with slight compression to immobilize the breast in the MLO and CC projections. Image acquisition is 10 minutes. One million coincident counts are obtained for image production. Spatial resolution in in the order of 1.5mm, the highest resolution of any biochemical breast imaging modality. This resolution is in the order of size of breast ductal structures.

As the detectors are positioned close to the target organ, image acquisiton is efficient and there is little attenuation of counts so spatial resolution is much improved over whole body PET imaging.

PEM Flex Images of the Breast

PEM Flex	Pem Flex	X-ray	X-ray
Invasive ductal carcinoma with central necrosis	Multifocal cancer		Occult DCIS in a single duct

Clinical trials with a full-breast PEM device have shown high clinical accuracy in characterizing lesions identified as suspicious on the basis of conventional imaging or physical examination with high sensitivity preserved (91%) for intraductal cancers. Considering that intraductal cancer represents more than 30% of reported cancers, and is the form of cancer with the highest probability of achieving surgical cure, it is likely that the use of PEM will complement anatomic imaging modalities in the areas of surgical planning, high-risk monitoring, and minimally invasive therapy.

Naviscan PET Systems