Inclusion Criteria:
1. Histopathologically or cytologically confirmed malignant melanoma, hepatocellular carcinoma, colorectal cancer, pancreatic cancer, breast cancer, gastric cancer, and lung cancer.
2. Aged ≥18 and ≤75 years, with no gender restrictions.
3. ECOG score of 0 or 1.
4. Expected survival time ≥6 months.
5. At least one easily accessible lesion that can be biopsied within one month before or after the PET scan. The patient consents to using archived or fresh biopsy tissue samples for relevant analysis.
6. Blood routine and liver/kidney function must meet the following criteria: Blood routine: WBC ≥ 4.0×10⁹/L or neutrophils ≥ 1.5×10⁹/L, PLT ≥ 100×10⁹/L, Hb ≥ 90 g/L; PT or APTT ≤ 1.5 ULN; Liver/kidney function: T-Bil ≤ 1.5×ULN (upper limit of normal), ALT/AST ≤ 2.5×ULN or 5×ULN (for subjects with liver metastases), ALP ≤ 2.5×ULN (if bone or liver metastases exist, ALP ≤ 4.5×ULN); BUN ≤ 1.5×ULN; SCr ≤ 1.5×ULN; At least one measurable target lesion according to RECIST 1.1 criteria.
7. Women must use contraceptive measures during the study or for six months after the study ends (effective contraceptive methods include sterilization, hormonal intrauterine devices, condoms, contraceptive pills/devices, abstinence, or partner tubal ligation, etc.). Men must agree to use contraceptive measures during the study or for six months after the study ends.
8. Able to understand and voluntarily sign the informed consent form, with good compliance.
Exclusion Criteria:
1. Pregnant or breastfeeding women, or women planning to become pregnant during the study or within three months after administration, as well as individuals donating sperm or oocytes.
2. Individuals known or suspected to be allergic to the investigational drug or any of its components.
3. Individuals with significantly abnormal liver or kidney function: serum total bilirubin (TBIL) \> 1.5 × 20 µmol/L, or aspartate aminotransferase (AST) \> 2.5 × 45 µmol/L, or alanine aminotransferase (ALT) \> 2.5 × 40 µmol/L, or serum creatinine \> 1.5 × 130 µmol/L.
4. Unable to cooperate in completing the PET scan, or suffering from claustrophobia or other conditions that prevent cooperation during the PET scan.
5. Other situations deemed inappropriate for participation in the trial by the investigator. Female patients who are pregnant or breastfeeding.
