Fluorodeoxyglucose positron emission tomography with sentinel lymph node biopsy for evaluation of axillary involvement in breast cancer.

BACKGROUND

This study analysed the value of [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) in detecting axillary lymph node involvement in women with breast cancer.

METHODS

In the first 150 women in this prospective study, axillary lymph node dissection (ALND) was performed regardless of the PET results. In a second group (125 women) FDG-PET was complemented with sentinel lymph node biopsy (SLNB) only in those who did not have pathological axillary uptake.

RESULTS

The sensitivity and specificity of FDG-PET in detecting axillary involvement was 84.5 and 98.5 per cent respectively in the whole series of 275 patients, with two false-positive and 22 false-negative results. False-negative results were associated with some intrinsic tumour characteristics. In 21 women, PET revealed pathological uptake, suggesting involvement of the internal mammary lymph node chain. Whole-body PET identified a second synchronous tumour in five asymptomatic patients and haematogenous metastases in two patients.

CONCLUSION

The high positive predictive value of PET (98.4 per cent) suggests that FDG uptake in the axilla could be an indication for full ALND without previous SLNB.