As well as improved clinical diagnosis, there are organisational cost savings and other benefits to introducing sFLC assays. The laboratory issues and costs were analysed in 2004 at the Christie Hospital in Manchester, UK . Superior analytical performance of the serum assays, faster reporting times and reduced laboratory costs were identified (Table 24.1). Cost benefits in relation to clinical outcomes were not analysed in this study but they may accrue from earlier diagnosis and by treatments that reduce morbidity. It is well known that a delay in the diagnosis of MM is associated with more complications and reduced disease-free survival .
|Sensitivity||1.5 mg/L||50 mg/L|
|Analysis time||15 minutes||1 hour|
|Reporting turnaround||1 hour||1 week|
|Cost per year (700 requests)||£6,500||£4,500|
|Extra staff costs per year||£0||£1,000|
|24-hour urine bottle usage||Not relevant||£1,000|
|Storage needs||30 cm3||10 m3|
Table 24.1. Analytical and cost/benefit study of sFLC and urine electrophoresis tests .
Most comparisons of the relative cost/benefits of serum versus urine FLC analysis have been made in the context of screening studies and these are presented in Section 23.6. In addition to the financial benefits, Tschautscher et al.  comment that monitoring with sFLC analysis in place of 24-hour urine analysis is likely to result in better patient compliance, because urine tests are both bothersome and time consuming.