Findings: Gallium scan initiated on 8/10/99 with images at 48 and 72 hours which demonstrates the following:

There is activity identified in the region of the patient's BROVIACŪ catheter located at the left upper chest. This highly reflects some extravasation and/or artifact of the radiopharmaceutical since the agent was administrated through the BROVIACŪ catheter .

There is a focus of activity seen at the posterolateral aspect at approximately the right 9th rib. SPECT imaging demonstrates this focus to be predominantly superficial. There is no abnormal activity seen in the corresponding ribs on the bone scan from 8/5/99.

There is a focus of activity seen left of midline overlying the pelvis. Oblique views demonstrate it to be predominantly superficial.

There is a large focus of intense activity seen at the right proximal medial thigh soft tissue which correlates with known palpable right groin mass as well as recent MRI and bone scan.

There is increased focal activity seen in the metadiaphysis of the left proximal tibia corresponding with bone scan.

Diagnosis: Lymphoma.

Discussion: Lymphoma can be localized, evaluated and followed up with Gallium 67 scan. However, PET scan is currently the best diagnostic and follow-up mode.

The mechanism of Gallium uptake remains controversial. In neoplastic disease it has been shown to correlate with metabolic activity as well as histologic liability. Gallium is immediately bound to plasma proteins but dominantly transferent when infused. It is thought that lymphomas have transferent receptors at their cell membranes.

25% of excretion occurs within the first 24 hours, primarily through the kidneys. At 24 hours, primarily excretion is through the intestine mucosa and somewhat by the liver/bile. Renal activity after 24 hours is considered abnormal. The remaining 3/4ths of the agent is retained for a prolonged period in the bones/bone marrow, the liver and to a lesser extent the spleen, the salivary and lacrimal glands. There is also a transient colonic accumulation. Therefore, persistence of Gallium activity in a given area of abdomen is considered abnormal.

Gallium uptake can be seen in the breasts during lactation, pregnancy and oral contraceptive administration. Chemotherapy can cause accumulation of Gallium at the thymus (rebound reaction) and parotid glands (contains lymphoid tissue; i.e. lymphoid reaction).

Gallium's main utility is for lymphoma staging. In untreated Hodgkin's disease, (HD) the sensitivity is greater than 85 to 90% with regards to histologic types (little variation in sensitivity). In non-Hodgkin's disease, sensitivity is variable with regards to histologic types; 90 to 60%.

References:
Mettler FA, Guiberteau MJ. Essentials of Nuclear Medicine Imaging, 4th Edition.
W. B. Saunders, Co.;1998.

McLaughlin AF, McGee MH, Grenau R, et al: Current role of Gallium Scanning in the
Management of Lymphoma. Euro J Nucl Med. 1990;16:755-771.

Larsen SM, Rasi JS, Allen RD, et al. Common Pathway for Tumor Uptake of Gallium-67
and Iron-59 via a Transferen Receptor. J Natl Cancer Inst. 1980; 64:51-53.

Murray IP, Ell PJ, Nuclear Medicine in Clinical Diagnosis and Treatment.
Churchill-Livingston; 1994.

BROVIAC is a registered trademark of C.R. Bard, Inc and its related company, BCR, Inc.

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