Inclusion Criteria:

- Recipients of renal allograft with current actinic keratosis I or II or successfully
treated actinic keratosis III (inclusion possible immediately after completed wound
healing from surgical excision), invasive squamous cell carcinoma (SCC), basal cell
carcinoma and/or premalignant neoplastic skin lesions

- Age 18 years and older

- Minimum period of 6 month after renal transplantation

- Stable renal function and a calculated creatinine clearance of at least 40 ml/min

- Written informed consent

- Proteinuria ≤ 800 mg/d at time of enrolment

- Successfully treated solid tumor (no recurrence or metastasis in the last 2 years)

Exclusion Criteria:

- Current Sirolimus- or Everolimus- intake

- Instable graft function (creatinine clearance < 40 ml/min)

- Graft rejection within the 3 previous months

- Proteinuria > 800 mg/d

- Non-controlled hyperlipidemia (Cholesterol >7,8 mmol/l, Triglycerides > 4)

- Leucopenia < 2500/nl

- Thrombocytopenia < 90/nl

- Pregnancy or breastfeeding

- Women of childbearing age without highly effective contraception (= defined as those
which result in a low failure rate (i.e. less than 1 % per year))

- Known allergy to macrolides

- Current participation in other studies

- Refusal to sign informed consent form

- Neoplasm other than defined as inclusion criteria

- All contraindications to SRL (see package insert, appendix)

- Persons who are detained officially or legally to an official institute