P>Context In the management of patients with medullary thyroid carcinoma (MTC), calcitonin doubling time (dt) has gained interest as an independent predictor of recurrence and survival.... Show moreP>Context In the management of patients with medullary thyroid carcinoma (MTC), calcitonin doubling time (dt) has gained interest as an independent predictor of recurrence and survival. Objective To perform a structured meta-analysis of the diagnostic value of calcitonin dt, carcinoembryonic antigen (CEA) dt and the combination and to define dt strata with the highest predictive power. Design The study was a meta-analysis using individual data. Methods Ten studies containing data on the post-operative kinetics of tumour marker(s) and (recurrence free) survival were included. Results Calcitonin- and CEA-dt are significant indicators for survival (hazard ratios (HR) 21 center dot 52 respectively infinite for dt 0-1 year compared to dt > 1 year) and recurrence (HR 5 center dot 33 respectively 6 center dot 80 for dt 0-1 year compared to dt > 1 year). The highest predictive power was found for the dt classification 0-1 year vs. > 1 year. CEA dt has a higher predictive value than calcitonin dt in the subgroup of patients for which both parameters were available. Conclusion The dts of both calcitonin and CEA are strong prognostic indicators for MTC recurrence and death. CEA dt has a higher predictive value than calcitonin dt and therefore measuring both tumour markers is essential for proper risk stratification. Show less
Many cost-of-illness studies have investigated the impact of rheumatoid arthritis on productivity, invariably concluding that productivity costs are high. Different methods exist to value... Show moreMany cost-of-illness studies have investigated the impact of rheumatoid arthritis on productivity, invariably concluding that productivity costs are high. Different methods exist to value productivity. The human-capital method takes the patient's perspective and counts any hour not worked as an hour lost. By contrast, the friction-cost method takes the employer's perspective, and only counts as lost those hours not worked until another employee takes over the patient's work. Both methods can produce widely different results. Productivity costs have the potential to compensate for the costs of expensive biological agents, but only in early-onset disease when patients still have jobs and if productivity is given full weight by using the human-capital method. If productivity is given less weight by excluding productivity costs or by using the friction-cost method, then currently, biological agents are probably too expensive. Show less
