3.1 Patient characteristics
The clinical characteristics of the investigated group are presented inTABLE 1 . We reviewed a total of 374 pediatric patients with the
four NHL subtypes; the median age was 9 years (range, 1–18 years).
There were 283 male (75.7%) and 91 female patients (24.3%). The
majority of patients were diagnosed as BL (n = 180; 48.1%) and
LBL (n = 95; 25.4%); the remaining patients were diagnosed as
ALCL (n = 64; 17.1%) and DLBCL (n = 35; 9.4%). There
were 327 patients (87.4%) at an advanced stage (stage III/IV) at
diagnosis; 159 (42.5%) and 152 patients (40.6%) were stratified into
the intermediate- and high-risk group, respectively. At diagnosis, the
incidence rate of bone marrow (BM) and central nervous system (CNS)
involvement was 18.7% (70 cases) and 9.6% (36 cases), respectively.
After BFM 95 chemotherapy, 322 (86.1%) and 9 patients (2.4%) achieved
CR and SD, respectively. Twenty-one patients (5.6%) died. Treatment
response evaluation was not available in 14 patients (3.7%) due to
discontinuation of therapy. Of these, eight (2.1%) were still under
treatment at the time of the last follow-up. The median follow-up time
was 28.5 months (range, 1–76 months) for all patients. The estimated
5-year EFS and OS were 74.2% and 85.7%, respectively. In total, events
were recorded for 82 patients (21.9%), including PD (n = 29;
7.6%), relapse (n = 31; 8.3%), secondary malignancy or LCH
(n = 4; 1.1%), and death (n = 42; 11.2%). Some patients
had >1 type of event. Among the four cases with secondary
malignancy or LCH, one female patient with BL and one male patient with
B cell-LBL (B-LBL) (CNS-positive) were diagnosed as secondary acute
myeloid leukemia (AML-M5) 2 months and 36 months after achieving CR,
respectively. They both then died of cancer. One male patient with DLBCL
was diagnosed as B cell ALL (B-ALL) (Ph+), and another male patient with
T cell LBL (T-LBL) was diagnosed as LCH 15 months and 26 months after
achieving CR, respectively. They were both alive and were under
chemotherapy at the last follow-up date.