PET IMAGING FOR EARLY DETECTION OF METASTASIS IN TRIPLE NEGATIVE BREAST CANCER

Abstract

Early and accurate detection of metastatic spread is crucial for improving outcomes in patients with triple‐negative breast cancer (TNBC), a subtype notorious for rapid dissemination and poor prognosis. In this prospective study, 50 high‐risk TNBC patients (primary tumor >2 cm or lymphovascular invasion) underwent ^68Ga‐anti‐cMET nanobody PET imaging alongside standard CT/MRI staging. Dynamic PET acquisition over 60 minutes and static whole‐body scans at 90 minutes post‐injection were analyzed to determine lesion uptake (SUVₘₐₓ), and findings were validated against histopathology or three‐month follow‐up. Compared with CT/MRI, PET achieved superior diagnostic performance (sensitivity 90% vs. 75%; specificity 85% vs. 80%; AUC 0.92 vs. 0.83), reliably identifying micrometastases down to 0.7 cm. Mean SUVₘₐₓ for metastatic lesions exceeded adjacent tissue by >1.2 units. Radiologist confidence was higher for PET (mean Likert score 4.5/5) than CT/MRI (3.2/5), and PET findings prompted changes in treatment plans for 40% of patients. Cumulative detection curves over 12 months demonstrated a steeper rise in metastasis identification when guided by PET, suggesting potential for earlier therapeutic intervention. While cost and tracer availability warrant consideration, thematic interviews with oncologists underscored the clinical value of targeted PET in TNBC management. These results support integrating ^68Ga‐anti‐cMET PET into early staging protocols to enhance micrometastasis detection, refine patient stratification, and ultimately improve progression‐free and overall survival in TNBC.