Staging PET-CT Scanning Provides Superior Detection of Lymph Nodes and Distant Metastases than Traditional Imaging in Locally Advanced Breast Cancer.

Abstract

This study was designed to evaluate the role of a single 18-FDG positron emission tomography and computed tomography (PET-CT) scan in comparison to multiple organ-directed conventional investigations (CI) as a staging tool in locally advanced breast cancer (LABC) to detect regional and distant metastasis. All eligible patients were subjected to CI (chest X-ray, abdominal sonography, and bone scintigraphy) followed by a single 18-FDG PET-CT scan. Standard imaging criteria were used for diagnosis of metastasis. Histopathological confirmation was undertaken for suspicious lesions. An exploratory analysis was done to assess the impact of PET-CT on the staging of LABC and how it resulted in a change in management. The study included 79 patients of LABC. PET-CT detected distant metastasis in 36 (45.5%) patients while CI could identify distant metastasis in 20 (25.3%) patients. Two of the 36 patients in whom PET-CT detected distant metastasis were false positive. Overall PET-CT upstaged the disease in 38 (48.1%) patients as compared to CI: stage III to stage IV migration in 14 (17.7%) patients due to identification of additional sites of distant metastasis, and within stage III upstaging in 24 (30.3%) patients due to identification of additional regional lymphadenopathy. PET-CT led to a change in management plan in 14 (17.7%) patients. PET-CT has a role in identifying additional sites of regional lymphadenopathy and distant metastasis to upstage the disease in a significant number of LABC patients in comparison to CI; this would help in accurate staging, selecting optimal treatment, and better prognostication of disease.