USE OF THE INTERNATIONAL PROGNOSTIC INDEX AND THE TUMOR SCORE TO DETECT POOR-RISK PATIENTS WITH PRIMARY MEDIASTINAL LARGE B-CELL LYMPHOMA -A STUDY OF 37 PREVIOUSLY UNTREATED PATIENTS

We tested two prognostic models devised for intermediate-grade lymphom as, the age-adjusted international prognostic index and the tumor scor e, in 37 consecutive untreated patients treated for a diagnosis of pri mary mediastinal large El-cell lymphoma (PMLCL). Neither model selecte d for a group of patients with statistically significant differences i n rates of complete response, failure-free survival (FFS) and overall survival (OS). Because the level of beta microglobulin (beta(2)m) is c onsistently low in the serum of patients with PMLCL, despite bulky dis ease, we tested the median value of this continuous variable in the 37 patients and found it to be statistically significant for predicting FFS. A hypothetical tumor score model using the adjusted value for bet a(2)m improved the prognostic accuracy for achievement of complete res ponse (93% vs. 60%; P = 0.02), FFS (73% vs, 35%; P = 0.02), and OS (80 % vs. 55%; P = 0.05). This hypothetical model merits further testing i n a larger population of patients with PMLCL.