Treatment practices and response in Kaposiform hemangioendothelioma: a
multi-center cohort study
Abstract
Background and Objectives: Kaposiform hemangioendothelioma (KHE) and
tufted angioma (TA) are rare vascular tumors in children historically
associated with significant morbidity and mortality. This study was
conducted to determine first line therapy in the absence of available
prospective clinical trials. Methods: Patients from 17 institutions
diagnosed with KHE/TA between 2005-2020 with > 6 months
follow-up were included. Response rates to sirolimus and vincristine
were compared at 3 and 6 months. Durability of response and response to
other treatment modalities were also evaluated. Results: Of 159 unique
KHE/TA subjects, Kasabach-Merritt phenomenon (KMP) was present in 64
(40.3%) and only 2 patients were deceased (1.3%). Over 60% (n=96)
demonstrated treatment response at 3 months and >70%
(n=114) by 6 months (no significant difference across groups). The
vincristine group had higher radiologic response at 3 months compared to
sirolimus (72.7% vs 20%, p=0.03) but there was no differences between
these groups at 6 months. There were no differences in rates of
recurrent or progressive disease between vincristine and sirolimus.
Conclusions: In this large, multicenter cohort of 159 patients with
KHE/TA, rates of KMP were consistent with historical literature but the
mortality rate (1.3%) was much lower. Overall treatment response rates
were high (>70%) and there were no significant difference
in treatment response or durability of disease comparing sirolimus to
vincristine. Our results support individualized treatment decision plans
depending on clinical scenario and patient/physician preferences.
Response criteria and response rates reported here will be useful for
guiding future treatment protocols for vascular tumors.