Abstract 224P
Background
Staging of early breast cancer is a controversial issue. Current guidelines recommend consideration of a computed tomography (CT) scan of the chest, abdominal imaging and a bone scintigraphy (BS) for patients with clinically involved lymph nodes, big primary tumors and aggressive biologic subtypes. In clinical practice patients with early breast cancer are commonly staged with BS and CT scan of chest and abdomen. Nevertheless, additional value of bone scintigraphy in patients staged with CT scan remains not well studied.
Methods
All early breast cancer patients who were initially treated in the Oncology Department of Saint-Petersburg State University Hospital during period from January 2019 to March 2021 were included in this study. We retrospectively reviewed electronic medical records to identify all bone scintigraphies and CT scans performed on these patients during initial evaluation. Results of staging CT and BS were compared to evaluate the incidence of bone metastais not detected on CT scan, incidence of additional bone metasasis in the field of CT scan and of additional bone metastasis outside of CT scan field. Additionally, we reviewed how often bone scintigraphy changed therapeutic decisions.
Results
We identified 147 breast cancer patients staged with CT scan of chest and abdomen, of whom 73 (49,6%) had also undergone a bone scintigraphy. After complete staging 23 out of 147 patients (15,6%) were diagnosed with metastatic (stage IV) breast cancer. Out of 73 patients staged both with CT scan and BS 0 (0%) were upstaged because of BS results. Additional bone metastasis in CT scan field were detected in 1 out of 20 patients (5%). Additional bone metastasis outside of CT scan field were detected in 1 (5%) out of 20 patients. This metastasis was located in temporal bone. Bone scintigraphy changed therapeutic decisions in 0 patients.
Conclusions
Bone scintigraphy is often performed in breast cancer patients but plays very limited role in patients that were already staged with computed tomography scan of chest and abdomen. Undergoing this additional test doesn't change stage of the disease and doesn't detect additional bone metastasis in the majority of patients.
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.