AB 16. Immunomodifiers in combination with conventional chemotherapy in small cell lung cancer
Background: To evaluate the effect of immumotherapy on response,
survival and certain immunologic markers in SCLC patients receiving
chemotherapy.
Patients and methods: A total of 191 SCLC patients assigned to
receive either chemotherapy alone (group A) or combination of
chemotherapy and immunotherapy as follows: group B received
IFN-alpha, 3 million I.U, 3 times per week, group C received IFNgamma
3, million I.U, 3 times per week, group D received IFN alpha
and gamma 1.5 million I.U of each 3 times per week and group E
received IL-2, 9 million I.U twice weekly. Chemotherapy was the
same for all groups and consisted of eight cycles with carboplatin
AUC 6 mg/m2 intravenously (i.v) on day 1, ifosfamide 3.5 gr/m2 i.v
on day 1 and etoposide 200 mg/m2 total dose orally day 1-3, every
28 days. Patients completing CT were restaged, and those found to
have limited disease (LD), received primary site and prophylactic
cranial irradiation. Immunotherapy was continued throughout these
treatments and during follow-up period. Blood was taken before each
course of CT and during follow up, in order to measure T3, T4 and
T8 lymphocytes, NK cells and CTLs.
Results: Differences in response and survival were not significantly
different when all patients were considered. However, among patients
with LD, Kaplan- Meier analysis disclosed a survival benefit for group
B (P<0.05). The analysis of immunological measurements revealed that
the improvement of immunologic markers was always accompanied by
clinical improvement while deterioration of all markers (except from
NK cells in group E) was accompanied by disease progression, result
statistically not significant except from group C (P<0.05).
Conclusions: Among cytokines used in the study, only interferon-alpha
seems to confer a survival benefit to SCLC patients with limited disease. However, immunotherapy remains a challenge in the treatment of lung
neoplasms and should be further exploited.