A 43-year-old male with no significant past medical history and a family
history of breast cancer was found to have an elevated PSA of 15.3 on routine
screening. The patient had been asymptomatic with no complaints of urinary
dysfunction. He denied any systemic symptoms and had no complaints of bony
His rectal exam showed a smooth, non-enlarged prostate with no palpable
nodules. Other physical exam observations were within normal limits. He
underwent prostatic biopsy showing prostatic adenocarcinoma. The right and the
left base showed Gleason 6 (3+3) tumor involving less than 5% of tissue. The
right apex showed high-grade prostatic intraepithelial neoplasia. The left apex
showed Gleason 6 (3+3) tumor involving 17% of tissue.
A nuclear medicine bone scan showed increased radiotracer uptake in the
left humeral head and T8 vertebral body. The patient subsequently underwent MRI
of the spine, which revealed diffuse replacement of marrow at T8 level with no
extra osseous extension.
A CT-guided biopsy of the T8 lesion was performed to evaluate for
metastatic disease. The pathology, however, showed a normal bone marrow with no
definite evidence of carcinoma. There was a single cluster of free floating
cytokeratin-positive cells that was positive for CAM5.2 and negative for CK
AE1/AE3, PSA and prostatic acid phosphatase. These were thought to be
non-malignant cells and possibly a contaminant.
Bone scan, posterior
projection. The bone scan demonstrates focus of increased update at T8 and left
humerus (posterior projection).
T1W image of the left shoulder shows ill-defined decreased T1 marrow signal in
the humeral epiphysis. Coronal STIR image of the left shoulder shows no
abnormal marrow edema.
MRI of the prostate confirmed organ-confined disease with a 1.5 cm
× 0.9 cm tumor in the right peripheral zone extending along the capsule
and a 1.5 cm × 0.8 cm tumor in the left side along the capsule with no
evidence of capsule invasion bilaterally. There was no evidence of metastatic
lymph node involvement.
At this stage, the patient had clinically T1cN0 disease with a repeat
PSA value of 12.8. However, there was a concern about possible metastatic
disease to bones. MRI of the left shoulder showed decreased T1 signal in the
humeral epiphysis, but no evidence of any focal mass. These findings were
similar to that seen in the T8 vertebra. The patient was scheduled to undergo a
biopsy of this humeral lesion to evaluate for any evidence of metastatic
disease. The CT scan of right shoulder performed in preparation for biopsy
showed subarticular cystic lesions characteristic of degenerative disease.
Therefore, biopsy was not performed.
Prostate cancer is the most common cancer and second-leading cause of
cancer-related death in US men, with an estimated 217,730 cases in 2010. The
SEER database for patients who died in 2003 to 2007 in the United States found
an age-adjusted death rate of 24.7 per 100,000 men per year. The survival is
largely influenced by the stage at diagnosis, with almost 100% 5-year survival
of patients presenting with organ-confined disease compared with 30% for
patients with metastatic disease. The standard treatment options for patients
with localized disease include radical prostatectomy and radiation therapy,
including external beam radiation/brachytherapy with or without systemic
Comparison of left
and right humeral head fat signal. Notice the more normal, brighter signal on
the right side.
normal T1 signal on the T8 vertebral body (arrow). No marrow edema on STIR
sequence. Increased sclerosis on CT scan (used for biopsy).
Photos courtesy of Munir Ghesani, MD
However, treatment for advanced disease is directed toward disease
palliation. The standard options include androgen deprivation therapy and
chemotherapy for castrate-resistant prostate cancers. Recently, two new drugs
were approved for the treatment of metastatic prostate cancer, including
abiraterone acetate, a CYP17 inhibitor, and sipuleucel-T (Provenge, Dendreon).
Thus, it is imperative that metastatic disease to the skeleton is definitively
In conclusion, bone scan is an effective and sensitive initial
examination in patients with initial diagnosis of prostate cancer and increased
PSA values to exclude skeletal metastatic disease. However, there is lower
specificity for bone scan-positive lesions, except when there is a pattern of
extensive multifocal metastatic disease. Isolated suspected lesions, however,
need further radiographic evaluation (and occasionally cytologic sampling) to
confirm the presence of metastatic disease and exclude false-positive
Munir Ghesani, MD, is an attending radiologist at St.
Luke’s-Roosevelt Hospital Center and Beth Israel Medical Center, and a
HemOnc Today section editor. He is an associate clinical professor
of radiology at Columbia University College of Physicians and Surgeons.
Ronald Ennis, MD, is an attending physician and chief of radiation
oncology at St. Luke’s-Roosevelt Hospital Center.
Adie Friedman, MD, and Carlos Benitez, MD, are radiology attendings
at St. Luke’s-Roosevelt Hospital Center.
Sumit Talwar, MD, is a hematology oncology fellow at St.
Luke’s-Roosevelt Hospital Center.
For more information:
- Moore TE. Skeletal Radiol. 1994;23:257-260.
- Sprecher S. J Bone Miner Res. 2002;17:1929-1930.
- Vande Berg BC. Semin Musculoskelet Radiol.