Is there utility in metronomic chemotherapy in adolescent and young adult patients with refractory sarcoma?
I agree with Dr. @Dr. First Last. In the absence of a standard second or beyond-line therapy in the sarcoma relapse setting, particularly one in which the outcome is expected to be especially poor, one must balance a number of factors in selecting a salvage regimen. One of the most important of these is QoL. As such, factors such as outpatient vs inpatient administration, oral vs IV, and tolerability should all be weighed in the context of a patient's goal of therapy. Metronomic regimens can provide prolonged disease stabilization and improvement in symptoms which positively impact QoL. There are many options to choose from and without a clear "winner" the selection of a regimen should be individualized. I find metronomic therapy for my adolescent and young adult patients with refractory sarcomas to be an undervalued treatment option.
Unfortunately, there is a general lack of data to help answer this question. However, in a phase II study of pediatric patients (see below), there were some patients enrolled with bone sarcomas and only one had stable disease and no responses.
On the other hand, oral cytoxan given daily (arguable metronomic) can lead to responses when combined with agents such as vinorelbine in sarcomas such as rhabdomyosarcoma. Additionally, in the palliative setting, I have seen improvements in pain and temporary stability with oral etoposide given daily, which may also fit a metronomic delivery, though it may also be the cytotoxic effect.
I also suggest that it depends on the sarcoma histology when there might be utility.
Nonetheless, the best answer is probably sometimes there is utility, in some patients and depending on the histology of the sarcoma.