New nuclear medicine imaging techniques have improved diagnosis, staging and treatment planning for BC. GaPET is preferable to standard somatostatin receptor scintigraphy where available (ENETS guidelines); however, its role in the management of BC remains unclear.
All consecutive pts diagnosed with BC from two ENETS Centres of Excellence were identified retrospectively; pts with high grade tumours or lacking biopsy confirmation were excluded. Primary objective: to assess the impact of GaPET on clinical management in pts with BC.
Of 166 pts screened, 46 were eligible: 52% female, median age 57 years (range 21-86); type of BC: DIPNECH (4%), typical (44%), atypical (35%), not reported (17%); median Ki67 and mitotic count were 3 and 1, respectively. Stage: localised (63%), locally advanced (13%) and metastatic (17%); 27 pts (59%) had curative resection; 18 (39%) received palliative treatment (somatostatin analogue (12; 67%) chemotherapy (4; 23%), PRRT (1; 5%), debulking surgery (1; 5%)). A total of 47 GaPETs were performed with the following rationale: BC confirmation (4; 9%), primary tumour identification (2; 4%), post-surgical assessment (19; 40%), staging (patients with known BC present at time of GaPET) (19; 40%) and consideration of Peptide Receptor Radionuclide Therapy (PRRT) (3; 7%). Twenty-seven (57%) scans showed evidence of non-physiological uptake: median SUVmax 7.2 (range 1.42-53). Uptake rate in primary tumour, liver, lung, bone and lymph node metastases was high (80-100%). GaPET provided additional information in 37% (95%CI 22-51) of pts and impacted on management in 26% (95%-CI 12-41); 9 pts (21%) were identified to have occult sites of metastases. Out of the 19 pts with post-surgical GaPET, 3 (16%) were identified distant metastases. There were no differences in the rate of practice changing GaPET results by type of BC (p-value 0.5). No factors predictive of changes in management were identified (logistic regression).
Our results support the use of GaPET in patients with BC for planning treatment, including post-surgical assessment due to potential for identifying occult metastases.
Clinical trial identification
Legal entity responsible for the study
The Christie NHS Foundation Trust and Royal Liverpool and Broadgreen University Hospitals NHS Trust
Dr Angela Lamarca was part-funded by the Pancreatic Cancer Research Fund and Spanish Society of Medical Oncology Fellowship Programme
All authors have declared no conflicts of interest.