The Role of Thallium Scintimammography with Lateral Decubitus Positioning in the Diagnosis of Breast Cancer

Abstract

Objective: Many different positioning techniques have been attempted in the search for the best method of imaging the breast during scintimammography. A new, effective and comfortable method of positioning the breast is described. Thallium-201-chloride is further explored as an agent to detect breast cancer.

Methods: Forty-two women with either a palpable mass or abnormal mammogram were imaged in the lateral decubitus and anterior supine positions. Each patient was injected intravenously with 75–112.5 MBq (2–3 mCi) of ²⁰¹TI-chloride. Planar images of 10–15 min each were obtained beginning 10 min after injection.

Results: Lateral decubitus positioning was very comfortable for the patient and afforded maximum privacy. High-quality images were obtained with breast tissue and axilla clearly visualized. Breast-to-camera distance was minimized to less than 0.5 inch in many cases. The sensitivity of thallium scintimammography was 90% and the specificity was 86% in 26 lesions with pathologic correlation. The smallest lesion detected measured 0.8 cm.

Conclusion: Lateral decubitus positioning in scintimammography provides an alternative to prone positioning which is sensitive, comfortable and private. Thallium-201 scintimammography employing lateral decubitus positioning has an acceptable sensitivity and specificity for detecting breast carcinoma.