Relationship between primary tumour 18F-FDG uptake and immunohistochemical and clinical prognostic parameters in breast carcinoma

Abstract

Objective: The objective of this study was to investigate the relationship between level of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) accumulation in primary breast tumour assessed by positron emission tomography/computed tomography (PET/CT) and histopathological and clinical prognostic factors.

Material and methods: A retrospective analysis was performed using the medical records of 58 female patients (age range: 31-86 years, mean age: 56) with biopsy of proven breast carcinoma, and who had undergone ¹⁸F-FDG PET/CT examination before chemotherapy/surgery. The ¹⁸F-FDG uptake of breast tumours was calculated as tumour to background ratio (TBR), which was compared with histopathological and clinical prognostic parameters.

Results: The histology of the breast tumour in the 58 patients was ductal type in 52 (90%), lobular in 4 (7%), and mucinous in 2 (3%). Tumour size was ≤ 2cm in 31 (53%) patients, and>2cm in 27 (47%). The levels of TBRs were not significantly different between the patients groups with tumours of 2cm or less and greater than 2cm (P=0.131). No significant difference between levels of TBR was observed neither with regards to axillary lymph node involvement (P=0.065) nor in terms of distant metastases (p=0.123). No statistically significant difference was found in levels of TBRs between patients with c-erbB-2 receptor positive and negative ones (P=0.107). Progesterone receptor (PR) expression was observed in 33 patients (57%), and 25 patients (43%) were PR negative. As regards progesterone receptor status, a statistically significant difference was observed in mean TBR levels between patients with and without progesterone receptor expression (P=0.020). Oestrogen receptor expression was positive in 41 (71%) patients, and negative in 17 (29%) patients. The difference in the levels of TBRs between patients with and without oestrogen receptor expression was at the level of significancy (P=0.050).

Conclusions: It is concluded that ¹⁸F-FDG uptake correlates with progesterone negativity of the tumour. However, a significant association with clinical prognostic parameters and level of ¹⁸F-FDG uptake levels could not be demonstrated.

Keywords: (18)F-FDG; Breast carcinoma; Carcinoma de mama; Prognosis; Pronóstico; Tumour to background ratio; Índice tumor/fondo.