Time-dependent effect of non-Hodgkin's lymphoma grade on disease-free survival of relapsed/refractory patients treated with high-dose chemotherapy plus autotransplantation.
Evaluation of time to event outcomes usually is examined by the Kaplan-Meier method and Cox proportional hazards models. We developed a modified statistical model based on histologic grade and other variables to describe the time-dependent outcome for autologous stem cell transplant (autotransplant) performed for non-Hodgkin's lymphoma (NHL) based on histologic grade and other variables. One hundred and fourteen relapsed or refractory NHL patients were treated using BCNU 600 mg/m2, etoposide 2400 mg/m2, and cisplatin 200 mg/m2 IV followed by autotransplant. Median age was 53.5 (range: 25-70) years, 78 patients had aggressive NHL and 36 indolent NHL. Seventy-five patients received involved-field radiotherapy just prior to transplant. At a median follow-up of 33 (range: 3 to 118) months, the estimated 5-year Kaplan-Meier probabilities of overall survival and disease-free survival were 61% and 51%, respectively. Cox proportional hazards model analysis showed that proportionality did not hold for lymphoma grade, indicating that the relationship between the grade and disease-free survival differed over time. By piece-wise Cox model, the relative risk for experiencing relapse or death after 1 year in patients with indolent compared with patients with aggressive NHL was 2.81 (p=0.019) with 95% confidence interval (1.19, 6.65). The time-dependent effect of lymphoma grade on disease-free survival suggests the need for early (within first year) incorporation of novel therapeutic approaches in management of patients with indolent NHL undergoing autotransplant.
Fu
P
P
Department of Epidemiology and Biostatistics, Case Comprehensive Cancer Center, Cleveland, Ohio 44106, United States. pxf16@case.edu
van Heeckeren
W J
WJ
Wadhwa
P D
PD
Bajor
D J
DJ
Creger
R J
RJ
Xu
Z
Z
Cooper
B W
BW
Laughlin
M J
MJ
Gerson
S L
SL
Koç
O N
ON
Lazarus
H M
HM
D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002330:Carmustine / Q000008:administration & dosage; D002945:Cisplatin / Q000008:administration & dosage; D018572:Disease-Free Survival; D005047:Etoposide / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000401:mortality* / Q000473:pathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D016016:Proportional Hazards Models; D033581:Stem Cell Transplantation; D013995:Time; D014182:Transplantation, Autologous; D016896:Treatment Outcome
D005047:Etoposide; D002945:Cisplatin; D002330:Carmustine