Inclusion Criteria

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)