Contrary to most standards of practise, gallium-67 whole body imaging is still being performed for neoplastic staging of lymphomas. Many centres have now moved away from this and use F18-FDG as part of their protocol. However having said that, a whole body scan along with a four bed SPECT/CT was performed to aid in the staging process.
Indication: Staging of neoplasm. Lymphoma of the left tibia.
Findings: Intense gallium avid lesion in the left proximal tibia and fibula, corresponding to a know bony lesion at this site. Further gallium avid activity are localized in 3 sites on the left parietal region of the skull, along with another foci of activity in the left parietal skull. In addition, abnormal gallium activity is found midline to the abdomen below, but separate to the transverse colon. No other soft tissue abnormality is observed.
Hx: Imaging with gallium-67 has been around for almost 40 years, first described by Edward and Hayes in 1969 (J Nucl Med. 1969;10:103–105).
It has been used in a variety of indications such as inflammation, infection and tumour localization (osteosarcomas, lymphomas, testicular tumours, melanomas), but for the most part, gallium has been used in oncology to stage and monitor the response of tumours to treatment.
With regards to imaging, most patients are scanned 72 hours post injection. Encouraging them to drink lot's of fluids within the first 24 hours is done to eliminate gallium from the genitourinary system, afterwards the patient may take a laxative to help in eliminating the gallium through the bowels.
Upon 72 hours, a whole body gallium image is taken. Depending on the clinical site, the arms may be raised to allow better visualization of the axillary regions or they may be left down by their side. SPECT/CT is also used afterwards to improve the specificity and sensitivity of the study.
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