The use of scintimammography for detecting the recurrence of loco-regional breast cancer: histopathologically proven results.

BACKGROUND: 99mTc tetrofosmin scintimammography has been shown to be an accurate diagnostic test in patients with a symptomatic breast lesion and for whom a non-diagnostic mammogram has been obtained. Since a physical examination and conventional imaging modalities have their limitations in the detection of recurrent breast cancer, and survival is related to the extent of recurrent disease, complementary imaging modalities are warranted.

AIM: To evaluate the role of 99mTc tetrofosmin scintimammography in detecting the recurrence of loco-regional breast cancer.

PATIENTS AND METHODS: Fifty-four patients underwent 55 scintimammography studies because either there were clinical indications of breast metastases, or there was a recurrence of metastases in the chest wall, and/or an evaluation of axillary, parasternal, supraclavicular and/or infraclavicular lymph node metastases was required. Planar breast imaging was performed 10 min after intravenous injection of 700 MBq 99mTc tetrofosmin.

RESULTS: 99mTc tetrofosmin scintimammography was diagnostic in 50 of the 55 studies. An unknown lung metastasis was detected in one patient, and an unknown bone metastasis of the sternum was detected in another. Tumour involvement remained undetected in one neck node metastasis. Three patients had false positive scintimammography results, with 99mTc tetrofosmin uptake in an axillary, infraclavicular and parasternal lymph node, respectively. A fourth patient showed 99mTc tetrofosmin uptake in the scar, which appeared to be an inflammatory lesion, proven by a histopathological biopsy and 1 year clinical follow-up.

CONCLUSION: 99mTc tetrofosmin scintimammography accurately detected 100% of the local recurrences independently of the extent of the preceding surgical intervention. The sensitivity and specificity of the technique for the detection of regional recurrent disease were 93% and 90%, respectively. These results are substantially higher than those of other imaging modalities.