VERIFICATION AND COMPARISON OF 2 DIFFERENT PREDICTIVE EQUATIONS IN HODGKINS-DISEASE

Background and Objective. In recent years, two predictive equations to estimate median expected survival at diagnosis for patients affected with Hodgkin's disease have been developed at the University of Pavia Medical School. The present retrospective work was aimed at testing co rrelation between mean survival estimated using the two equations and observed survival, and at comparing the results of the two different e quations. Methods. Fifty-three deceased patients were considered from a series of 114 consecutive ones. All these patients had been treated in a conventional way according to therapeutic modalities similar to t hose used in the series from which the two equations were derived. Exp ected median survival values calculated with the older, linear equatio n and with the newer exponential one were compared with observed survi val. Results. Mean survival of the whole series was over 24 years, wit h survival probabilities of 85% after 5 years and 74% after 10 years. Using the first predictive equation on the 53 deceased patients result ed in a satisfactory correlation between estimated median survival and real survival: Pearson's R correlation coefficient value is 0.5996, w ith a t value of 5.35 and p<0.001. The more recent exponential predict ive equation showed a better correlation between estimated median surv ival and observed survival: R=0.7338, t=7.71, p<0.001. Interpretation and Conclusions. The new exponential equation, while apparently comple x, is superior to the older one, and is a very reliable and straightfo rward tool for estimating median expected survival: its forecast prove s to be an important pretreatment parameter in every HD patient. These observations support widespread use of this tool in clinical practice to evaluate the prognosis of Hodgkin patients in a more accurate and flexible way. (C) 1997, Ferrata Storti Foundation.