Applications in Oncology: Breast Cancer

Breast cancer is currently the most common malignancy detected among women. The most important factor determining long-term prognosis is the involvement of the axillary lymph nodes. Currently, dissection (ALND) is the technique of choice for making this determination. However, it is an invasive procedure requiring a hospital stay, and has the potential for long-term complications.

PET is a non-invasive and painless alternative to ALND for screening patients referred for partial mastectomy. Only those patients whose PET studies indicate axillary involvement need undergo the ALND procedure, thus sparing an estimated 75% of these patients from the cost and expense of dissection.

Although PET is unlikely to replace current methods for finding a primary breast tumor, it has potential for screening certain populations of women - specifically, young patients with dense breasts, or those with strong family histories of the disease; those with fibrocystic disease; those whose needle aspirations have been inconclusive; and those with negative needle aspirations who nevertheless warrant high suspicion of disease.

Whole-body PET scans are also being used to determine the extent of disease at initial diagnosis, to stage patients for surgery, and to monitor the effectiveness of therapy.

Clinical Example:

54-year-old female. Lump located in left breast. Sent for PET to determine extent of disease.

Primary tumor on left breast is evident and lymph node involvement in the left axilla detected.