Stereotactic Radiation Therapy for Pediatric Sarcomas

Pediatric patients with sarcoma who have limited metastases are still potentially curable
with aggressive local therapy. However, conventional moderate dose radiation is unlikely to
provide durable local control. Given the recent technologic advances in radiation delivery,
it is now possible to deliver tumoricidal doses, using stereotactic radiation over a short
time course with highly focal techniques. Stereotactic radiation has proven efficacious in
the intracranial setting and in multiple extracranial sites in adults. It has not yet been
well studied in the pediatrics population where there is a particularly strong rationale due
to the ablative doses that can be delivered to tumor while simultaneously reducing high dose
to normal tissues. The proposed trial is a single arm phase II study to determine the
efficacy of SBRT in pediatric sarcomas with surgically unresectable metastatic disease.
Oligometastatic sites eligible for treatment in this study include bony sites of disease.
SBRT will be delivered to each eligible site to a total dose of 4000 delivered in 5 fractions
of 800 per fractions each day. Following completion of SBRT, patients will undergo treatment
response assessment with the use of diagnostic imaging, clinical examination, and completion
of the Brief Pain Inventory to assess quality of life. The primary objective of this study is
to determine the efficacy of SBRT delivered to a dose of 4000 in 5 fractions of 800 each for
patients greater than 3 years of age and < 40 years of age with metastatic disease of bone
secondary to pediatric sarcoma. The secondary objectives of this study include describing the
toxicity of SBRT with this regimen; assessing clinical response rate of each target lesion;
assessing long-term clinical outcomes; and assessing quality of life following completion of
treatment. For patients with potentially curable oligometastatic disease, surgical resection
in conjunction with systemic therapy remains the standard of care. Patients on this study
will continue to receive chemotherapy outside of the 2 week window for SBRT. Issues that may
limit participation include our inability to assess late effects that may not develop till at
least 10 years after therapy. For this reason, we will limit the population in this study to
patients who are surgically unresectable and would be otherwise incurable with current
standard systemic therapies.

Inclusion Criteria:

- confirmed sarcoma of the soft tissue or bone

- must have measurable disease via CT scan

- tumor malignancies must meet certain criteria to be eligible

- greater than 3 years of age

- less than or equal to 40 years of age

- life expectancy of at least 9 months

- adequate performance status

- ability to understand and willingness to sign informed consent document

Exclusion Criteria:

- patients who have had chemotherapy or radiotherapy within 2 weeks prior to entering
the study

- patients who have had any prior radiotherapy to the treatment site(s)

- patients may not participate on any other treatment protocol while they are receiving
treatment on this protocol and for up to 3 months after these protocol treatments have
ended

- pregnant women

- refusal of women of child bearing potential to take a pregnancy test prior to
treatment