Persistent Disease:
Given the chronic nature of KHE/TA, we also tried to define disease
persistence in response to therapy (Supplemental Table 3). We found that
rates of persistent disease at 3 months (28.6%, p=0.024) were higher in
patients receiving a combination of Siro+VCR compared to those receiving
steroids alone (and a significantly higher proportion of patients in the
Siro+VCR group required continuation of therapy at 3 months for
persistent disease (71.4%, p<0.001). However, by 6 months,
rates of persistent disease were equivalent across groups.
When looking at just the VCR and Siro groups (Table 5), a higher
proportion of patients in the Siro group were reported to require
continuation of therapy at 3 months for persistent disease (27.5% vs.
0%, p=0.003). However, of the VCR group, 22/25 (88%) received
adjunctive therapy including 9 (36%) who had Siro added to their
regimen and time to initiation of Siro ranged from 29 days to 863 days.
Rationale for adding Siro included severity of disease in 5 patients,
VCR toxicity in 2 patients (hoarse cry, neutropenia), and loss of
central venous access in 2 patients. In the sub-analysis of sirolimus or
vincristine treatment with or without steroid use (Table 6), more
patients had persistent disease in the two vincristine groups, but small
numbers precluded statistical comparison. It was notable that in the VCR
+ steroid group, 9/19 (47.4%) patients had Siro added to their
treatment regimen later.