Inclusion Criteria

- INCLUSION CRITERIA:

2.1.1.1 Histological diagnosis: Pathologically confirmed diagnosis of 1) invasive breast
cancer, 2) ductal carcinoma in situ, or 3) adenocarcinoma of the prostate.

2.1.1.2 Patients in whom the management of the histologic diagnosis will include radiation
treatment as part of standard clinical management.

2.1.1.3 Patients in whom the extent of disease is considered local or locoregional (ie.
requiring definitive radiotherapy to the breast or prostate).

2.1.1.4 Patients must be older than 18 years of age.

2.1.1.5 Patients must have a primary medical or surgical oncologist in the community or at
NCI who is wiling to collaborate with the ROB staff in the clinical management of the
patient.

2.1.1.6 Patients of childbearing or child- fathering potential must be willing to use a
medically acceptable form of birth control, which includes abstinence, while they are
being treated with radiotherapy on this study.

2.1.1.7 Patients must have an ECOG performance status of 0-2 and a life expectancy greater
than 12 months.

EXCLUSION CRITERIA:

2.1.2.1 Patients with a history of chronic skin disease such as psoriasis, eczema, or
history of keloid formation.

2.1.2.2 Patients requiring concurrent use of topical steroids

2.1.2.3 Patients requiring concurrent use of glucocorticoid therapy.

2.1.2.4 Patients who have received topical or systemic chemotherapy within 4 weeks of
enrollment (not including hormonal agents such as antiandrogens, GnRH agonists, aromatase
inhibitors, tamoxifen, and similar agents) are excluded.

2.1.2.5 Patients requiring concurrent chemotherapy with radiotherapy except as noted in
2.1.2.3 are excluded.

2.1.2.6 Patients with a history of lupus erythematosis, scleroderma, ataxia telengiectasia
or other known hypersensitivity to therapeutic radiation.

2.1.2.7 Patients with prior radiotherapy to the site which would be used for blister
induction.

2.1.2.8 Patients who are pregnant because of the potential mutagenic effects of radiation
on a developing fetus or newborn.

2.1.2.9 Patients with unrelated systemic illness which in the judgment of the Principal
Investigator (PI) would compromise the patient's ability to tolerate this therapy or are
likely to interfere with the study procedures or results.

2.1.2.10 Patients who are in the estimation of the PI, deemed unable or unlikely to adhere
to protocol treatment.

2.1.2.11Patients with significant skin atrophy that would interfere with blister
formation.

2.1.2.12Breast cancer patients in whom the site of radiotherapy includes a myocutaneous
flap or skin graft.

ELIGIBILITY CRITEREIA FOR HEALTHY VOLUNTEERS:

INCLUSION CRITERIA:

2.2,1.1 Healthy volunteers older than 18 years of age.

2.2.1.2 Ability to provide informed consent.

EXCLUSION CRITERIA:

2.2.2.1 History of chronic skin disease such as psoriasis, eczema, or history of keloid
formation.

2.2.2.2 Concurrent use of glucocorticoid therapy.

2.2.2.3 History of lupus erythematosis, scleroderma, ataxia telengiectasia or other known
hypersensitivity to therapeutic radiation.

2.2.2.4 Prior radiotherapy to the site which would be used for blister induction (for
benign or malignant causes).

2.2.2.5 Unrelated systemic illness which in the judgment of the Principal Investigator
(PI) would compromise the patient's ability to tolerate blister induction or are likely to
interfere with blister healing, the study procedures, or the study results.

2.2.2.6 Darkly pigmented skin in whom pigmentation changes are a likely complication

2.2.2 7 Significant skin atrophy that would interfere with blister formation.