RATIONALE: Extracranial stereotactic radiosurgery may be able to send x-rays directly to the tumor and cause less damage to normal tissue.

PURPOSE: This phase I/II trial is studying the side effects and best dose of extracranial stereotactic radiosurgery and to see how well it works in treating patients with solid tumors.

OBJECTIVES:

Primary

• Establish the maximum tolerated dose (MTD) of extracranial stereotactic radiosurgery in patients with isolated tumors. (Phase I)
• Determine the minimum dose required for local control. (Phase II)

Secondary

• Determine the radiographic response rate.
• Determine the median time to progression of the treated tumor.
• Evaluate the toxicity of treatment.
• Evaluate the cause of death.

OUTLINE: This is a phase I dose-escalation study followed by a phase II open-label study. Patients are stratified according to tumor size.

• Phase I: Patients undergo stereotactic radiosurgery to one lesion. Cohorts of 3-6 patients undergo escalating doses of stereotactic radiosurgery until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose at which 33% of patients experience dose-limiting toxicity within 3 months of treatment.
• Phase II: Patients undergo stereotactic radiosurgery to one lesion at the MTD or at the dose at which local control at 3 months is ≥ 80%, as determined in phase I.

After completion of study treatment, patients are followed at 1 month, 3 months, and then every 3 months thereafter.

PROJECTED ACCRUAL: At least 48 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

• Presence of well-circumscribed tumor on contrast-enhanced CT scan or MRI

  • Maximum diameter of 6 cm

PATIENT CHARACTERISTICS:

• Life expectancy ≥ 3 months
• Not pregnant
• Fertile patients must use effective contraception
• Negative pregnancy test
• Must be able to tolerate CT scan or MRI contrast

PRIOR CONCURRENT THERAPY:

• At least 3 weeks since prior chemotherapy or immunotherapy
• No prior treatment on this study
• No chemotherapy or immunotherapy during and for 4 weeks after completion of study treatment
• No concurrent external-beam radiotherapy overlapping with the radiosurgically-treated volume (including low-dose regions)