FDG PET/CT imaging could be considered a valid tool for the prognostic evaluation of patients with breast cancer after primary treatment during a long follow-up period and is superior to CT, according to a presentation made at the European Association of Nuclear Medicine Congress in Vienna last week.
The goal of the study was to assess the prognostic value of FDG PET/CT and CT in patients with breast invasive ductal cancer, already treated with surgery and chemotherapy (neoadjuvant or adjuvant) and/or radiotherapy, according to Laura Evangelista, MD from the Istituto Oncologico Veneto in Padova, Italy.
The study enrolled 157 females with a previous history of invasive ductal breast cancer after primary treatment. All the patients underwent both CT and FDG PET/CT exams within three months for evaluation of disease status. The median interval time between the last treatment (surgery and chemotherapy and/or radiotherapy) and imaging exams was 55 months. Follow-up data were obtained with clinical evaluation and/or radiological findings, said Evangelista.
The followup was 100 percent complete in a period of 13 months. Of the overall patients, 33 percent had evidence of clinical and/or radiological relapse of disease, while 67 percent did not, according to Evangelista and colleagues.
Negative predictive value and positive predictive value for disease relapse or progression was 83 percent vs. 77 percent and 44 percent vs. 38 percent, respectively for PET/CT and CT.
The researchers found that relapse-free survival in patients with negative PET/CT was significantly different (78 percent) from patients with positive PET/CT (20 percent). In patients with negative and positive CT, relapse-free survival was 53 percent and 38 percent, respectively.
PET/CT imaging could be considered a valid tool for the prognostic evaluation in patients with breast cancer after primary treatment during a long period of followup. For the identification of disease relapse, FDG PET/CT has demonstrated high negative predictive value but low positive predictive value, although superior to CT, concluded Evangelista and colleagues.