PT  - JOURNAL ARTICLE
AU  - Lam, Marjorie
AU  - Yang, Johnny
AU  - Vijayakumar, Vani
TI  - A Rare Case of Orbital Metastasis from Invasive Lobular Carcinoma: Challenges of <sup>18</sup>F-FDG PET/CT and the Search for Consensus on Imaging
AID  - 10.2967/jnmt.124.267732
DP  - 2024 Dec 01
TA  - Journal of Nuclear Medicine Technology
PG  - 337--339
VI  - 52
IP  - 4
4099  - http://tech.snmjournals.org/content/52/4/337.short
4100  - http://tech.snmjournals.org/content/52/4/337.full
SO  - J. Nucl. Med. Technol.2024 Dec 01; 52
AB  - Invasive lobular carcinoma (ILC) frequently underlies orbital metastasis. A 74-y-old woman, who was current with mammograms and had no cancer history, presented to her ophthalmologist with visual complaints and was found to have metastatic ILC. MRI was contraindicated, and an 18F-FDG PET/CT scan revealed a mildly hypermetabolic right orbital mass and low uptake in the left subareolar breast, suggestive of metastatic ILC. Small studies have found that in ILC, 16α-18F-fluoroestradiol and fibroblast activation protein inhibitors are more avid than 18F-FDG. There is currently no consensus regarding imaging for ILC. Many people have contraindications to MRI, and the higher rate of false-negative findings on mammography for ILC than for other breast cancers makes this patient population more vulnerable to inaccurate staging, incorrect assessment of tumor burden, and, consequently, insufficient treatment. We provide this interesting case to highlight the potential of 18F-fluoroestradiol PET/CT and fibroblast activation protein inhibitors over 18F-FDG in this breast cancer subtype.