A phase 2 double blind randomised study of PraevoSkin,a melatonin containing emulsion, in the prevention of radiation induced dermatitis.

Inclusion Criteria:

1. Female patients at least 18 years with unilateral breast cancer following lumpectomy +/- chemotherapy.
2. Planned to receive 50 Gy whole breast irradiation +/- boost to tumor bed.
3. ECOG PERFORMANCE STATUS 0-1.
4. Capable of giving written informed consent and following instructions for applying study emulsion or placebo as per control.
5. No co-morbidities known to affect radiotherapy reactions.
6. No co-existing acute or chronic skin disease.
7. No evidence of infection or inflammation of breast to be treated.
8. Not receiving chemotherapy during radiotherapy course.Biological therapy (e.g. Herceptin) or hormone therapy will be allowed during the study.

Exclusion Criteria:

1. Chemotherapy within 4 weeks prior to planned start of radiation or chemotherapy planned during radiation.
2. Prior radiotherapy to any site.
3. Collagen vascular disease.
4. Diabetes mellitus requiring medication.
5. Uncontrolled hypertension.
6. Participation in other clinical study.
7. Any contra-indicating to treatment with Melatonin.
8. History of allergy to peanuts or fragrances.
9. History of severe allergic reactions (e.g. asthma).

Female patientsplanned to receive whole breast radiation.