Clinical significance of routine pre-cystectomy bone scans in patients with muscle-invasive bladder cancer.
OBJECTIVE
To evaluate the clinical significance of bone scans taken routinely before total cystectomy in patients with bladder cancer of clinical stage > or = T2.


METHODS
Of 227 consecutive patients with stage > or = T2 bladder cancer diagnosed between 1980 and 1990 but with no clinical suspicion of bone metastases, 91 had a pre-cystectomy bone scan performed at the Norwegian Radium Hospital. The medical records of these patients were reviewed to examine the subsequent development of distant metastases and survival.


RESULTS
Of the 91 patients, 37 (41%) developed skeletal bone metastases after cystectomy, unrelated to the clinical T category. In 35 patients, the pre-cystectomy bone scan showed pathological uptake of isotope which was interpreted by the specialist in nuclear medicine as suspicious of (13 patients) or probably caused by (22 patients) skeletal metastases. In either circumstance, the clinician decided that total cystectomy was precluded, particularly as most of the changes could be explained radiologically as being degenerative. In the individual patient, there was no clinically useful correlation between the findings on the pre-cystectomy bone scan and the clinical course of disease, nor if serum alkaline phosphatase (SAP) level was included as an additional predictive factor. However, although not statistically significant, the follow-up of all patients revealed an association between the degree of change on the pre-cystectomy bone scan and the subsequent development of skeletal metastases and cancer-corrected survival.


CONCLUSIONS
Unless further investigations, particularly magnetic resonance imaging (MRI), can be performed, the findings of a routine pre-operative bone scan are usually unable to identify patients with bladder cancer of stage > or = T2 who will not be cured by total cystectomy. An increased level of SAP did not improve the predictive accuracy of a pre-cystectomy bone scan. However, the results indicate that future clinical research should be directed at combining the findings of bone scans and MRI in the search for micrometastases.
Braendengen
M
M
Department of Medical Oncology and Radiotherapy, Norwegian Radium Hospital, Montebello, Norway.
Winderen
M
M
Fosså
S D
SD
D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D002295:Carcinoma, Transitional Cell / Q000000981:diagnostic imaging* / Q000556:secondary; D015653:Cystectomy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019042:Muscle Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D009361:Neoplasm Invasiveness; D011300:Preoperative Care; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D001749:Urinary Bladder Neoplasms / Q000473:pathology / Q000601:surgery*