Diagnosis of recurrent breast cancer: 18F-FDG PET/TAC as first choice

Abstract

10681 Background: we began using PET diagnosis in 1994 and since the beginning of 2000 we started with a PET/CT system. Aim of our study was to evaluate if this new imaging modality may be the first step in the detection of recurrence in patients with a history of breast tumors. Methods: we reviewed retrospectively 22 patients (mean age 60, range 46–76 years) already treated for a breast cancer. A total of 32 PET/CT scans were performed (repeated in 10 patients). All patients were submitted to other examinations, such as bone scintigraphy and liver ecography, but also mammography and CT scan. Results: 14/32 PET/CT were negative for recurrence in 10 patients (4 scans as a second one). In a mean follow up of 10 months, 1 case is not yet clear: in presence of relevant increase of Ca15.3 (up to 176 ng/ml) the first scan was negative and the second one evidentiated a pattern of lung inflammation. Among the other 13/14 negative scans, 3 patients presented ambiguous/positive bone scintigraphy for metastases, not assessed at the final diagnosis. 18/32 PET/CT scans were positive for local recurrence or distant metastases. Among these positive cases, a patient with normal bone scintigraphy presented a mild uptake of FDG in the right omerus. The second scan (5 months later) showed focal increased uptake of FDG in the same bone site, not evident in the CT images, and many small lung nodules, 1–2 mm size. In 3 patients PET localized muliple bone lesions, in 2 CT was completely normal. Finally, 1 out of the 18 positive results was false positive: a patients with a single lung nodule (1.5 cm) was submitted to surgery and the final diagnosis was benign lesion. PET/CT was crucial for the patient’s management in 19 out of 22 patients. Conclusions: recurrent breast cancer is generally characterized by multiple sites of metastases and few cases take advantage of surgical resection. In our group of 22 patients just 2 out of them received surgery (for local relapse and lung metastases). Therefore, in most cases a whole body examination, like PET/CT may be more useful respect to other modalities to assess how spread is the recurrence. Further data are needed but, in our preliminary experience, PET/CT seems to be the first choice to evaluate patients with previous breast cancer. No significant financial relationships to disclose.