Inclusion Criteria:

- Limited primary or metastatic lung tumors with no evidence of uncontrolled
extrathoracic metastases

- Up to 4 lesions may be included, with none larger than 5 cm if there are more than
one, or up to 7 cm if there is a single tumor

- Both peripheral and central tumors are accepted for this trial.

- Age > 18 years old

- Both men and women and members of all races and ethnic groups are eligible for this
trial.

- Note: Patients may be enrolled more than once (e.g. for a new tumor)

Exclusion Criteria:

- Evidence of uncontrolled extrathoracic metastases

- Contraindication to receiving radiotherapy.

- Contraindication to receiving radiotherapy

- Age < 18 years old. Children are excluded because lung malignancies rarely occur in
this age group. Furthermore, treatment requires a great deal of patient cooperation
including the ability to lie still for several hours in an isolated room.

- Pregnant and breastfeeding women are excluded; as well as women of child-bearing
potential who are unwilling or unable to use an acceptable method of birth control
(hormonal or barrier method of birth control; abstinence) to avoid pregnancy for the
duration of the study. Male subjects must also agree to use effective contraception
for the same period as above. Should a woman become pregnant or suspect she is
pregnant while participating in this study, she should inform her treating physician
immediately.