Table 6.

Correlation between efficacy and timing of I-131 tositumomab anti-CD20 radioimmunotherapy in relation to other treatments for low-grade and transformed CD20 positive B-cell lymphoma

	1st therapy	2nd therapy	3rd therapy	4th therapy
Number of patients	141	226	228	540
Response rate, %	95	73	58	46
Median response duration, months	Not reached	35	16	12
Complete response rate, %	78	46	32	23
PFS >1 year, %	82	59	42	27

Modified from Gregory et al. [51]; PFS, progression free survival