V8: Is There a Role for PET/CT in Locoregionally Recurrent Breast Cancer?

Tuesday, March 1, 2022

5:22 PM – 5:25 PM CST

Location: Zoom Meeting

Virtual Poster Presenter(s)

Sara M. Grossi, MD

Breast Surgical Oncology Fellow
Cedars Sinai Medical Center
Los Angeles, California, United States

Disclosure: Disclosure information not submitted.

Participants should be aware of the following financial/non-financial relationships:

Sara M. Grossi, MD: Disclosure information not submitted.

Introduction:

Locoregional recurrence (LR) following breast cancer (BC) treatment is associated with a risk of developing distant metastases. There is controversy regarding the role of staging scans in asymptomatic patients who present with LR. The purpose of this study was to assess utilization of PET/CT imaging, examine diagnostic imaging findings, and determine whether there is benefit of PET/CT imaging in this patient population.

Methods:

A review of a prospectively maintained institutional database of patients diagnosed with Stage I-III invasive BC between 2008 and 2019 was performed. All asymptomatic (without clinical evidence of systemic disease) patients with LR following BC treatment were identified and categorized into two groups: those who underwent PET/CT imaging at diagnosis of LR and those who did not. The groups were compared with respect to patient, tumor, and imaging characteristics, treatment, and survival.

Results:

200 patients with LR were included. Of these patients, 53% (N=107) received PET/CT and 47% (N=93) did not. Those who received PET/CT were more likely to have T2 or greater disease on initial primary diagnosis and were more likely to have recurrence detected by palpation than those who did not (60.4% vs. 32%, p< 0.001 and 15.9% vs 11.2%, p=0.008, respectively). Of patients who underwent PET/CT, 62.6% (N=67) had a positive imaging finding with the ipsilateral breast as most common site (50.8%, N=48) followed by ipsilateral axillary lymph nodes 21.5%(N=15) and ipsilateral chest wall 12.3%(N=11). PET/CT only identified distant metastasis in 9.3%(N=10) of patients. These patients were more likely to have HER2+ tumors compared to patients with negative PET/CT findings (50% vs. 12.7%, p=0.021). Patients with LR who underwent PET/CT had poorer overall mean survival compared to those who did not receive imaging with a median follow-up of 3.1 years from time of LR (24.8 years versus 35.6 years, p=0.004).

Conclusions:

Despite frequent use of staging scans in asymptomatic BC patients presenting with LR, distant metastases were rarely detected, and omission did not adversely affect survival. PET/CT has limited diagnostic yield in this patient population, although there may be a benefit for those with Her2+ disease.

Learning Objectives:

Identify utilization patterns of PET/CT and CT in patients with locally recurrent breast cancer.
Describe the various sensitivities and specificities of different imaging modalities used to identify metastatic breast cancer in patients presenting with local recurrence and benefits and limitations of each modality.
Identify characteristics and tumor biology of breast cancer patients who are more likely to present with distant metastatic disease on presentation with local recurrence