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 ro utinely before total cystectomy in patients with bladder cancer of cli nical stage greater than or equal to T2. Patients and methods Of 227 c onsecutive patients with stage greater than or equal to T2 bladder can cer diagnosed between 1980 and 1990 but with no clinical suspicion of bone metastases, 91 had a pre-cystectomy bone scan performed at the No rwegian Radium Hospital, The medical records of these patients were re viewed to examine the subsequent development of distant metastases and survival. Results Of the 91 patients, 37 (41%) developed skeletal bon e metastases after cystectomy, unrelated to the clinical T category, I n 35 patients, the pre-cystectomy bone scan showed pathological uptake of isotope which was interpreted by the specialist in nuclear medicin e as suspicious of (13 patients) or probably caused by (22 patients) s keletal metastases. In either circumstance, the clinician decided that total cystectomy was precluded, particularly as most of the changes c ould be explained radiologically as being degenerative, In the individ ual patient, there was no clinically useful correlation between the fi ndings on the pre-cystectomy bone scan and the clinical course of dise ase, nor if serum alkaline phosphatase (SAP) level was included as an additional predictive factor. However, although not statistically sign ificant, the follow-up of all patients revealed an association between the degree of change on the pre-cystectomy bone scan and the subseque nt development of skeletal metastases and cancer-corrected survival. C onclusion Unless further investigations, particularly magnetic resonan ce imaging (MRI), can be performed, the findings of a routine pre-oper ative bone scan are usually unable to identify patients with bladder c ancer of stage greater than or equal to T2 who will not be cured by to tal cystectomy, An increased level of SAP did not improve the predicti ve accuracy of a pre-cystectomy bone scan. However, the results indica te that future clinical research should be directed at combining the f indings of bone scans and MRI in the search for micrometastases.