Purpose: To evaluate the relationship between FDG uptake and prognostic factors of breast cancer such as hormone receptors (estrogen and progesterone), expression of c-erbB-2, axillary lymph node status, tumor histology, grade and size.
Materials and methods: Between May 2009 and February 2011; 79 patients (mean age ± SD: 52.9 ± 13.9 years) with biopsy proven breast cancer underwent F-18 FDG PET/CT scanning for staging. Patients with excisional biopsy or neoadjuvant chemotherapy were excluded from the study. Histological types included were invasive ductal carcinoma (n = 68), invasive lobular carcinoma (n = 2), and invasive ductal plus lobular mixed carcinoma (n = 9). Maximum standardized uptake values (SUVmax) were compared with estrogen (ER) and progesterone receptors (PR), expression of c-erbB-2, as well as tumor grade and tumor size. For the evaluation of relationship between tumor SUVmax values and prognosticators such as hormone receptors, tumor histologic grade, and tumor size, statistical analyses were performed using Student t test, Mann-Whitney U Test and Pearson correlation coefficient and p values of less than 0.05 were considered to indicate statistically significant differences.
Results: All primary breast neoplasms were detected by PET/CT scanner. The mean SUVmax values and breast cancer tumor sizes ranged from 2.09 to 39.0 and 0.7 to 10 cm, respectively. Tumors with negative ER [(n = 19); SUVmax median (min-max): 15 (2.09-39.0)] were associated with higher SUVmax values (p = 0.01). Tumors with overexpression of C-erbB-2 [(n = 28); SUVmax median (min-max): 16.0 (5.0-39.0)]; tumor grade 3 [(n = 25); SUVmax median (min-max): 15 (6.43-39)]; axillary lymph node involvement [(n = 60); SUVmax median (min-max): 13.61 (4.0-39.0)]; tumor histopathology and increased tumor size were associated with higher maximum standardized uptake values. However, PR did not show any relationship with SUVmax values.
Conclusion: In the present report, strong relationships were detected between the negativity of ER, overexpression of c-erbB-2, tumor grade, tumor size, histopathology, axillary lymph node involvement and SUVmax values. Accordingly, we believe that SUVmax values obtained with (18)F-FDG PET/CT may provide some information about tumor biology of breast cancer.