Aj. Grillo-lopez et al., Response criteria for NHL: Importance of 'normal' lymph node size and correlations with response rates, ANN ONCOL, 11(4), 2000, pp. 399-408
Background: Oncologic literature cites many different definitions of critic
al response measurements.
Patients and methods: Response criteria (RC) for non-Hodgkin's lymphoma (NH
L) were developed by lymphoma experts, endorsed by international lymphoma c
linicians, and applied to a 166-patient rituximab (Rituxan(R), MabThera(R))
trial by a third-party, blinded panel of NHL experts (LEXCOR). Retrospecti
vely, we analyzed this data using variations of the original RC and compari
ng with recently published RC.
Results: The definition of a 'normal' lymph node affected the complete resp
onse (CR) rate (less than or equal to 1.0 x 1.0 cm, 6%; less than or equal
to 1.5 x 1.5 cm, 18%; less than or equal to 2.0 x 2.0 cm, 28%); overall res
ponse rate (ORR) was not affected. CR rates increased progressively without
greater than or equal to 28 days response confirmation: 12% vs. 6% (less t
han or equal to 1.0 x 1.0 cm), 26% vs. 18% (less than or equal to 1.5 x 1.5
cm), and 36% vs. 28% (less than or equal to 2.0 x 2.0 cm). CR rate and dur
ation of response (DR) were unaffected when only the six largest, rather th
an all lesions, were measured. When the new RC were applied, CR rate (32%)
was higher and DR (13.9 months) and time to progression (15.6 months) were
shorter in complete responders.
Conclusions: Standard RC must be consistently and rigorously applied for ac
curate comparisons between studies.