18F-FDG micro-PET/CT for intra-operative margin assessment during breast-conserving surgery

Abstract

Rationale: Positive surgical margins for invasive breast cancer (BC) treated with breast-conserving surgery (BCS) are defined as ink on tumor. The rate of positive margins is approximately 20%, since a time- and cost-effective method for margin assessment is lacking. In this study, we investigated margin status by intra-operative imaging using high-resolution ¹⁸ F-fluoro-deoxyglucose (FDG) positron emission tomography (PET) and X-ray computed tomography (CT).

Methods: Twenty patients were enrolled and received 4 MBq/kg of FDG prior to surgery. Intra-operative imaging of the specimens was performed by the MOLECUBES β-CUBE (PET) and X-CUBE (CT). Margin status was assessed by three surgeons and compared with an algorithm. The sensitivity and specificity were calculated by using histopathological assessment as a gold standard.

Results: A region with high FDG uptake was visualized in all specimens. Automated analysis showed a sensitivity of 90%, a specificity of 60%, and an area under the curve (AUC) of 0.86 after ROC analysis. Margin assessment by the surgeons resulted in a mean sensitivity and specificity of 79% and 72%, respectively.

Conclusions: This proof-of-concept study demonstrates that high-resolution FDG-PET/CT can facilitate intra-operative margin assessment during BCS. This technique achieves good sensitivity and specificity and may therefore reduce re-operation rates in the future.

Keywords:

• Breast-conserving surgery
• resection margins
• intra-operative assessment
• invasive breast cancer
• imaging
• surgery

Disclosure statement

Radosław Marcinkowski, Vincent Keereman, and Roel Van Holen are employees of MOLECUBES NV. Roel Van Holen and Vincent Keereman are shareholders of MOLECUBES NV. All other authors have no conflict of interests to declare.

Additional information

Funding

This work was supported by Innovatiemandaten grants no. HPC.2016.0240 and HPC.2017.0515 by Agentschap voor Innovatie door Wetenschap en Technologie (IM-IWT).