ABSTRACT

Tc-99m methoxyisobutylisonitrile scintigraphy is a diagnostic method commonly used for cardiac perfusion imaging. It is also used for parathyroid, lung, breast, thyroid, brain, melanoma, lymphoma, bone, and soft tissue primary and secondary tumors imaging. Our case aims to report a breast cancer incidentally revealed by Tc-99m methoxyisobutylisonitrile scintigraphy.

A 49-year-old female patient was admitted to the cardiology department with atypical angina. Tc-99m methoxyisobutylisonitrile scintigraphy showed myocardial perfusion was within normal limits but a focal uptake was detected in the lateral superior quadrant of the left breast. Ultrasonography detected a lesion with irregular borders in the outer quadrant of the left breast and a lymph node with increased thickness of the cortex in the left axilla. Magnetic resonance imaging showed a mass with a spiculated contour in the outer quadrant of the left breast and lymph nodes with increased cortex thickness in both axillae. By the histopathologic examination, the specimen was diagnosed with invasive ductal carcinoma.

Although Tc-99m methoxyisobutylisonitrile scintigraphy is mainly used for myocardial perfusion imaging, the entire image area should be examined in detail and further investigation should be done for incidental focal lesions that were previously undetected.

Keywords: Tc-99m methoxyisobutylisonitrile, breast cancer, scintigraphy, incidental