This study aims to compare the diagnostic performance of 18F-FDG and 18F-FSPG PET/CT in lung, breast, and abdominal cancers before undergoing therapy. In addition, the role of 18F-FSPG PET/CT in evaluating therapy response and prognosis will also be evaluated.

Inclusion Criteria:

• Patients are given the opportunity to participate in the study if

  1. Age ≥ 20 years old.
  2. Confirmed diagnosis of primary cancer of the following: NSCLC, breast or abdominal cancers
  3. ECOG performance status 0 to 2.
  4. Life expectancy > 3 months.
  5. Consent to perform additional 18F-FSPG and 18F-FDG PET prior to therapy.
  6. Sexually active subjects agree to use condoms and/or their partners of reproductive potential to use a method of effective birth control during imaging period of 2 weeks.

Exclusion Criteria:

• Patients with any of the following conditions will be excluded

  1. Had received previous treatment (excluding neoadjuvant therapy).
  2. Pregnant or lactating women.
  3. Known malignancy in other organs.
  4. Evaluated by primary care physician as unsuitable.
  5. Known hypersensitivity to the study drug.

Patients with clinical diagnosis of NSCLC, breast, and abdominal cancers