Mammoscintigraphy

Excerpt

Breast cancer is increasing in incidence and is one of the leading types of cancer. Once thought to be mostly a disease of elderly females, there is an increase in the incidence of breast cancer in women during their third and fourth decades of life. With increasing awareness, screening has become more prevalent, which in turn has increased the overall number of positive findings. Additionally, post-treatment monitoring increases with an overall increase in studies and survival rates. In an effort to decrease the morbidity and mortality of breast cancer, technological advances in breast imaging have been developed and are continuing to expand to detect breast cancers earlier. Methods of examination for breast cancer include self physical examination, physician physical examination, mammogram, tomography, ultrasound, magnetic resonance imaging (MRI), and positron emission tomography (PET). Another less commonly known and rarely used modality is scintimammography or mammoscintigraphy. Scintimammography is a type of nuclear medicine imaging, which has been considered adjuvant to mammography specifically for cases containing post-surgical changes, indeterminate mammogram findings, post neoadjuvant chemotherapy follow-up, and suspected multifocal disease. MRI of the breast has largely taken the place of scintimammography because it can provide similar information and more such as a high-quality preoperative evaluation. Currently, clinicians have not decided on definite indications for scintimammography, resulting in many studies evaluating its utility.

Studies have attempted to define the importance of scintimammography by comparing statistical data, including positive predictive values, false negatives, and false positives. The positive predictive value is low for mammograms, given the higher rates of false positives, but when combined with another modality, the positive predictive value will increase, which improves patient care and satisfaction overall.

Breast malignancies have been shown to have increased uptake of radiopharmaceuticals as compared to normal breast parenchyma. The diagnostic evaluation consists of intravenous injection of technetium 99m sestamibi (technetium 99m - DMSA or technetium 99m MDP can also be used but are less sensitive) with subsequent imaging of the breasts.