68 Gallium-Fibroblast Activating Protein Inhibitors-46 Positron Emission Tomography - Computerized Tomography for Molecular Assessment of Fibroblast Activation and Risk Assessment in Solid Tumors

Inclusion Criteria:

1. Patients must have histologically or cytologically solid tumors at any stage, if biopsy is no feasible for technical reason or risk benefit balance, patients may be enrolled if CT or MRI strongly suggest oncological lesion;
2. 18-Fluorine-2-fluoro-2-deoxy-D-glucose fluorodeoxyglucose Positron emission tomography / Computerized tomography or other clinical practice morpho-functional imaging scan dubious or inconclusive;
3. Male or Female, aged\>18 years
4. Eastern Cooperative Oncology Group (ECOG) performance status \<2 (see Appendix A)
5. A female participant is eligible to participate if she is not pregnant and not breastfeeding. If female of childbearing potential highly effective birth control methods, according to guideline "Recommendation related to contraception and pregnancy testing in clinical trials", (See Appendix D) are mandatory. Highly effective birth control methods are required beginning at the screening visit and continuing at least 6 months following last treatment with study drug. Male patient and his female partner who is of childbearing potential must use 2 acceptable methods of birth control (1 of which must include a condom as a barrier method of contraception) starting at screening and continuing throughout the study period and for 6 months after final study drug administration. Two acceptable methods of birth control thus include Condom (barrier method of contraception) and one of the following is required ( established use of oral, or injected or implanted hormonal method of contraception by the female partner; placement of an intrauterine device (IUD) or intrauterine system (IUS) by the female partner; additional barrier method like occlusive cap with spermicidal foam/gel/film/cream/suppository in the female partner; tubal ligation in the female partner; vasectomy or other procedure resulting in infertility (eg., bilateral orchiectomy), for more than 6 months.
6. Participant is willing and able to give informed consent for participation in the study.

Exclusion Criteria:

1. Participation in another clinical trial with any investigational agents within 30 days prior to study entry or 5 half lives of the study drug.
2. Medical or psychological conditions that would not allow the participant to understand, or sign the informed consent
3. History of allergic reactions attributed to compounds of similar chemical or biologic composition to Fibroblast Activating Protein Inhibitor or other agents used in the study.
4. Inability to remain still for the entire duration of the exam
5. Life expectancy \< 6 months
6. Eastern Cooperative Oncology Group (ECOG) performance status \> 2
7. Patient with compromised renal function (Creatinine\> 2 mg/ml)
8. Patient with altered hepatic function (AST and Alanine Aminotransferase \> 2.5 respect to upper normal limits)
9. Pregnancy and lactation
10. Subject deprived of its freedom by administrative or legal decision or who is under guardianship