Androgen and Estrogen Receptor Imaging in Metastatic Breast Cancer Patients as a Surrogate for Tissue Biopsies

Correlation plot of semiquantitative analysis of receptor status and SUV_max as measured by PET scan for AR (left) and ER (right).

Example of typical ¹⁸F-FES (A–C) and ¹⁸F-FDHT (D–F) distribution in same patient with multiple bone metastases. (A) Sagittal ¹⁸F-FES PET/CT fusion image with physiologic uptake in liver, small intestine, and urinary tract and pathologic uptake in multiple vertebra. (B) ¹⁸F-FES PET maximum-intensity-pixel format to allow visualization of biodistribution of ¹⁸F-FES tracer. (C) Horizontal ¹⁸F-FES PET/CT fusion image with physiologic uptake in small intestine and pathologic uptake throughout pelvic bones. (D) Maximum-intensity-pixel format of ¹⁸F-FDHT PET scan, with physiologic uptake in blood pool of heart and liver and excretion via bile to small intestine, and urinary tract. (E) Sagittal ¹⁸F-FDHT PET/CT fusion image with physiologic uptake and pathologic uptake in multiple vertebrae. (F) Horizontal ¹⁸F-FES PET/CT fusion image with physiologic uptake in large vessels and small intestines and pathologic uptake throughout pelvic bones.

Distribution of SUV_max per lesion per patient measured by ¹⁸F-FES PET. Lesions are divided into bone (blue), lymph nodes (red), lung (green), and others (purple). Orange circles are biopsied lesions. Blue boxes indicate ER-positive biopsies (>1% staining); numbers indicate score of biopsy (i.e., intensity times percentage positive cells). Dashed line indicates threshold set based on receiver-operating-characteristic analysis. White boxes indicate negative biopsies (<1% staining).