Question

bone scan (scintigraphy) is a useful imaging modality when a) determining a most likely diagnosis. b) evaluating soft tissue involvement of a lesion. c) determining additional sites of osseous metastatic involvement. d) evaluating direct extension from a primary carcinoma.

Explanation:

Bone scintigraphy (bone scan) is highly sensitive to increased bone turnover, which occurs in metastatic bone disease. It is used to screen the entire skeleton for additional sites of osseous metastases, as it can detect these lesions earlier than other imaging in some cases. It is not the first choice for definitive diagnosis (needs correlation), is poor for soft tissue evaluation, and not ideal for assessing direct primary tumor extension.

Answer:

C) determining additional sites of osseous metastatic involvement.