DISEASE CHARACTERISTICS:

• Patient

  • Confirmed diagnosis of basal cell nevus syndrome (BCNS)

  • Known patched (PTCH) gene mutation

    • Must have full sequence of coding exons with intron/exon junctions in the PTCH gene OR prior genetic testing confirming PTCH mutation by the Yale University DNA Diagnostics Laboratory

• Age- and sex-matched healthy participant (control)

  • Unaffected relative of patient OR normal healthy volunteer with no family history of BCNS or features of BCNS

    • No unrelated healthy participant meeting any of the following clinical criteria for BCNS:

      • Lamellar calcification of the falx cerebri
      • Prior odontogenic keratocyst or any jaw cyst for which a histopathologic diagnosis cannot be ascertained
      • Palmar or plantar pits typical of BCNS
      • More than 3 basal cell carcinomas (BCC) in a lifetime or 1 BCC under the age of 30
      • History of medulloblastoma

    • No unrelated healthy participant with 2 or more of the following features:

      • History of ovarian or cardiac fibroma
      • Mesenteric or pleural cysts
      • Polydactyly
      • Macrocephaly determined after adjustment for height
      • Craniofacial features of BCNS, including cleft palate, frontal bossing, hypertelorism, iris coloboma or other developmental defects of the eye, or coarse facies
      • Vertebral anomalies, including spina bifida occulta outside the lumbar region
      • Bifid or splayed ribs
      • Other radiographic findings, including bridging of the sella turcica, nonlamellar calcification of the falx cerebri, or flame-shaped lucencies in the phalanges = 1-3 BCCs over the age of 30

PATIENT CHARACTERISTICS:

• WBC ≥ 4,000/mm³
• Neutrophil count ≥ 2,000/mm³
• Platelet count ≥ 150,000/mm³
• Hemoglobin ≥ 11.5 g/dL
• Bilirubin 0.3-1.0 mg/dL
• AST 17-59 U/L
• PTT 10-13 seconds OR INR 1.0-1.4
• Creatinine clearance > 50 mL/min
• Cholesterol < 350 mg/dL
• Triglycerides < 400 mg/dL
• Not pregnant or nursing
• Negative pregnancy test
• Fertile participants must use effective contraception for ≥ 1 month before, during, and for ≥ 12 weeks after study treatment
• No active infection
• No alcohol or drug abuse
• No psychiatric disorder or mental deficiency that would preclude study compliance
• No uncontrolled hypertension (i.e., blood pressure > 140/90 mm Hg on > 2 measurements)
• No chronic active infection requiring treatment
• No untreated reactive purified protein derivative of tuberculin (PPD)
• No HIV-1 infection
• No infection requiring antibiotics within the past 30 days
• No other skin disease affecting broad areas of the body, including the region to be treated and biopsied
• No known hepatitis B or C infection (detectable RNA off antiviral therapy)
• No immune deficiency disorder
• No known hypersensitivity to sirolimus or macrolide antibiotics (e.g., erythromycin, azithromycin, or clarithromycin)
• No cancer within the past 5 years except basal cell skin cancer

PRIOR CONCURRENT THERAPY:

• At least 1 month since prior investigational drugs
• No concurrent dietary supplements, including Hypericum perforatum (St. John's wort) or megadose vitamins
• No other concurrent immunosuppressive medications, including corticosteroids
• No concurrent medications known to interfere with sirolimus metabolism
• No concurrent anticoagulants
• No concurrent acetylsalicyclic acid or other drugs affecting platelet function or number
• No routine (i.e., > 2 doses/week) use of nonsteroidal anti-inflammatory drugs

• No drugs or substances that would effect sirolimus blood concentrations, including any of the following:

  • Nicardipine
  • Verapamil
  • Clotrimazole
  • Fluconazole
  • Itraconazole
  • Troleandomycin
  • Cisapride
  • Metoclopramide
  • Clarithromycin
  • Erythromycin
  • Bromocriptine
  • Cimetidine
  • Danazol
  • HIV-protease inhibitors (e.g., ritonavir or indinavir)
  • Phenobarbital
  • Carbamazepine
  • Phenytoin
  • Rifabutin
  • Rifapentine
  • Grapefruit juice
  • Vaccinations (especially live vaccines)