THE ROLE OF PET CT IN CANCER OF UNKNOWN PRIMARY Primeri Bilinmeyen Kanserlerde PET BT'nin Rolü

Year 2023, Volume: 13 Issue: 2, 8 - 13, 15.06.2023

Ozan Kandemır Fadime Kandemir

Abstract

ABSTRACT
Objective: This study aimed to investigate the diagnostic value of positron emission tomography/computed
tomography (PET/CT) in detecting the primary focus and in suspicious foci in patients who underwent PET/
CT with a pre-diagnosis of carcinoma of unknown primary.
Material and Methods: In this retrospective study, a total of 49 patients who underwent PET/CT scan with
a prediagnosis of carcinoma of the unknown primary between 2015 and 2019, and whose clinical follow-up
and histopathological data were available, were included. PET/CT study was performed in 20 (40%) patients
after the metastatic lesion was detected as a result of pathology, and in 29 (60%) patients due to clinical
findings and imaging methods and suspicion of malignancy. The histopathological and clinical evaluation of
the patients before PET/CT and the primary surgery, histopathological examinations and clinical follow-ups
after PET/CT were examined. The success of PET/CT in detecting primary lesions and evaluating suspicious
lesions in metastatic cases was analyzed.
Results: Seventeen (34.7%) of the patients were female and 32 (65.3%) were male. A primary malignant
tumor was detected in 34 (85%) of 40 patients with PET/CT. Regional distribution in patients with primary
cancer focus; 9 pancreases, 9 lungs, 4 livers, 3 urothelial, 2 thyroids, 1 vertebra, 1 breast, 1 ovary, 1 esophagus,
1 prostate, 1 iliac bone, 1 skin, 1 stomach and 1 colon. In the follow-up of 6 cases whose primary could
not be determined; Cervical cancer was detected in 1, ovarian cancer in 1, and the primary focus could not
be detected in the clinical follow-up of 4 metastatic patients.
Conclusion: PET/CT is highly successful in detecting cancers whose primary is unknown. Therefore, PET/CT is
a diagnostic imaging method for the detection of the primary in cancer patients whose primary is unknown.

Keywords

THE ROLE OF PET CT IN CANCER OF UNKNOWN, PRIMARY, Primeri Bilinmeyen Kanserlerde PET BT

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