Metronomic chemotherapy for pediatric refractory solid tumors: A
retrospective single-center study
Abstract
Background: Metronomic chemotherapy (MC) is based on chronic
administration of chemotherapeutic agents at minimally toxic doses
without prolonged drug-free breaks. MC has a multitargeted action of
tumor angiogenesis inhibition and anticancer immune response stimulation
and may also directly affect tumor cells to induce tumor dormancy. At
our institute, MC has been introduced to treat patients with
refractory/relapsed pediatric tumors. Methods: We retrospectively
analyzed the data of pediatric patients with relapsed/refractory solid
tumors who received treatment, including low-dose continuous
administration of anti-cancer drugs. Results: Of the 18 patients, the
disease statuses at the initiation of MC were complete remission (
n = 2), partial remission/stable disease ( n = 5), and
progressive disease ( n = 11). The overall survival rate was 61%
at 12 months and 34% at 24 months, and the progression-free survival
rate was 21% at 12 and 24 months. Eleven of 18 patients, with tumor
stabilization or maintained remission/stable disease, showed certain
advantages in terms of overall survival rate. Even if limited to
progressive disease, the survival time of responders was prolonged
compared to non-responders (median 19.4 months vs. 4.7 months, P
= 0.012). Conclusion: Approximately half of the patients demonstrated
temporal tumor stabilization and improved survival time, although most
patients had progressive disease, and MC was administered as palliative
therapy. Large-scale studies on pediatric MC are rare; however, previous
reports and the present study support the conclusion that MC has the
potential to play an important role in pediatric cancer treatment during
the advanced stage, both in terms of prolonging life and maintaining
quality of life.