Photon-deficient finding in sternum on bone scintigraphy in patients with malignant disease

The sternum is known as a common site of bone metastasis in a variety of neoplasms. Sternal metastasis is usually visualized as hot spot on bone scintigraphy. However, photon deficiency in the sternum on bone scintigraphy is reported in few cases with malignancy. We undertook a retrospective analysis to clarify the clinical significance of photon deficiency in the sternum in 12 patients with malignancy. Twelve patients (five breast cancer, two multiple myeloma, one lung cancer, one renal cell cancer, one hepatocellular carcinoma, one malignant lymphoma, and one thyroid cancer) showing cold sternal metastasis on bone scintigraphy were identified among 9,430 patients in whom bone scintigraphy was performed. Except for two cases with pathologically confirmed sternal metastasis, all patients showed lytic change in the sternum on tomography or CT scan. Six cases of solitary sternal metastasis showed partial effect of systemic therapy (chemotherapy, humoral therapy, and radiation therapy) and surgical treatment. It is necessary to keep in mind that this type of lesion may occur as a manifestation of metastatic disease.