Incidence of exclusive extrapelvic skeletal metastasis in prostate carcinoma on bone scintigraphy

Figure 1 A 74-year-old male, with a newly diagnosed case of carcinoma of the prostate [Gleason’s Score 7 (4 + 3)] with serum prostate-specific antigen level 491 ng/mL and underwent whole body bone scintigraphy. A: ^99mTc methylene diphosphonate Whole body planar images show focal increased tracer uptake involving the cervical and lumbar vertebrae (arrow) raising the suspicion of metastatic disease; B: Axial computed tomography (CT) and fused single photon emission computed tomography (SPECT)-CT images show tracer localization to sclerotic lesion involving L3 vertebrae suggestive of metastatic disease. No metastatic disease was seen in pelvic bones on SPECT-CT.

Figure 2 A 66-year-old male with carcinoma of the prostate and serum prostate-specific antigen of 23. 3 ng/mL. A: Staging with whole body bone scintigraphy show focal areas of increased tracer uptake involving the right 6^th rib; B: Axial computed tomography (CT) and fused single photon emission computed tomography-CT images show tracer localization to the right 6^th rib anteriorly with a fracture line (arrow). The uptake was thus secondary to rib fracture post traumatic. There was no other abnormal uptake anywhere in the bones on whole body study.

Figure 3 A 77-year-old male with carcinoma of the prostate and a Gleason’s Score 8 (4 + 4) and serum prostate-specific antigen level of 100 ng/mL. A: Staging whole body bone scintigraphy show heterogeneously increased tracer uptake involving the left hemipelvis and focal areas of increased tracer uptake involving the right 8^th rib raising the suspicion of metastatic disease; B and C: Axial computed tomography (CT) and fused single photon emission computed tomography-CT images localizes the tracer to the left iliac bone with cortical thickening and bony expansion consistent with Paget’s disease (arrow in B) and to the right 8^th rib anteriorly with a fracture line (arrow in C).

Figure 4 A 76-year-old male, with a newly diagnosed case of carcinoma of the prostate underwent whole body bone scintigraphy. A: ^99mTc methylene diphosphonate Whole body planar images show solitary focal area of increased tracer uptake involving skull bone on the right side; B: Axial computed tomography (CT) and fused single photon emission computed tomography-CT images show tracer localization to the right parietal bone (arrow) with no significant CT abnormality to suggest of metastatic disease involvement. The lesion was thus considered indeterminate.