The purpose of this study is to assess the dosimetric properties of the positron emission tomography (PET) imaging probe 18F labeled Picolinamide (18F-P3BZA) and preliminarily evaluate its diagnosis value in melanoma patients.

50 patients with pathology diagnosed melanoma will be enrolled for the clinical study. If agree to take part in this study, the patient will be performed with 18F-P3BZA PET/CT scan and 18F-FDG PET/CT scan in the other day before and after surgery. Next, all of the resected tissues from the patients will be checked with pathology.

6 of 50 patients are performed for whole-body PET scans at 0, 15, 30, 45, 60, and 120 minutes and a CT scan at 60 minutes after tracer injection (mean dose, 5.0 ± 0.5 mCi in 2.0 ± 0.5ml) will be performed. During the imaging period, 1 mL blood samples will be obtained for time-activity curve calculations at 1, 5, 10, 30,60, 90, 120, and 180 minutes after injection. The estimated radiation doses will be calculated by using OLINDA/EXM software.

The images produced by these scans will be compared to see the diagnosis value of 18F-P3BZA.

Screening Tests:

Women who decide to take part in this study will be asked if they think they might be pregnant at the start of the study. All of them must have a negative blood pregnancy test (Human chorionic gonadotropin, HCG).

PET-CT Scan Procedure:

Before the PET-CT scan is performed, patient will be asked to remove any metallic objects when she/he arrive at the PET-CT Center. After a property rest, he/she will be injected with about 5mCi 18F-P3BZA. The first scan will take at 60 minutes after injection and a delay scan will take at 120 minutes after injection. Each PET/CT scan will take about 20 minutes.

After 18F-P3BZA scan, the patient will be asked to avoid stressful exercise. Starting about 12 hours before 18F-FDG scan, he/she will be asked to limit the amount of carbohydrates until the scans are done.

Follow-Up Visits:

Patients' primary care physician will follow-up them for next 24 hours. After then, they may order additional imaging or surgical results after this study for follow-up purposes. The study doctor will review these results to compare them with the PET-CT images. The study doctors will also review the results of any biopsies you may have had as a result of PET-CT findings.

This is an investigational study. PET-CT and CT scans are FDA approved and commercially available.

Inclusion Criteria:

• patients with melanoma: diagnosed by pathology and ready for surgery

Exclusion Criteria:

• patients with melanoma: refuse or cannot endure surgery
• pregnant women