F-flurodeoxyglucose (FDG) positron emission tomography(PET)/ computed tomography(CT) and
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F-fibroblast activation protein inhibitor (FAPI) PET/CT for patients with suspected recurrence of abdominal and pelvic malignant tumors after treatment.
Methods:
The clinical follow-up results
pathological data
and
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F-FDG PET/CT and
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F-FAPI PET/CT imaging results of patients with clinically suspected recurrence/metastasis of abdominal and pelvic malignant tumors after treatment who were admitted to the Sun Yat-sen University Cancer Centre from September 2021 to February 2024 were reviewed and analyzed. The patient’s medical history and clinical follow-up results were collected. The patient’s lesions were measured with the maximum standard uptake value (SUV
max
) and calculated the tumor-to-background ratio (TBR). SUV
max
and TBR were analyzed by Violin Plot and paired t-test. The diagnostic efficacy of
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F-FDG PET/CT and
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F-FAPI PET/CT was statistically compared.
Results:
Of the 64 patients (33 males
31 females) with clinically suspected recurrence/metastasis after treatment for abdominal and pelvic malignant tumors
52 had metastasis confirmed by clinical or pathological examination. There was no significant difference in SUV max between the two images (
P
>0.05). In the Violin Plot
the median SUV
max
of
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F-FAPI PET/ CT was higher than that of
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F-FDG PET/CT
and the distribution was more concentrated. TBR was statistically significant (
P
<0.000 1)
and the TBR of
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F-FAPI PET/CT was higher than that of
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F-FDG PET/CT. The sensitivity of
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F-FDG PET/CT and
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F-FAPI PET/ CT for diagnosing metastasis was 55.8% (29/52) and 88.5% (46/52)
the specificity was 83.3% (10/12) and 58.3% (7/12)
and the accuracy was 60.9% (39/64) and 82.8% (53/64)
respectively.
Conclusion:
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F-FAPI PET/CT is superior to
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F-FDG PET/CT for patients with suspected recurrence of abdominal and pelvic malignant tumors after treatment
especially in peritoneal metastases
and can be used as a complementary method when the