FDG PET/CT Improves Diagnosis of Synchronous Multiple Primary Malignant Neoplasms
A study published in Frontiers in Oncology reports that 18F-FDG PET/CT improves the diagnostic performance for synchronous multiple primary malignant neoplasms (SMPMNS) and is a good imaging modality for patients with SMPMNS.
Researchers from the departments of nuclear medicine and pathology at Jiangxi Provincial People’s Hospital (The First Afﬁliated Hospital of Nanchang Medical College), in Nanchang, China, retrospectively evaluated the clinical and imaging data of 37 patients with SMPMNS who had undergone18F-FDG PET/CT from October 2010 to December 2020. The study included 74 lesions identiﬁed in 37 patients with SMPMNS, with 94.6% of patients having double primary tumors. Of the incidences of SMPMNS, 18.9% occurred in the same organ system, with respiratory tumors being the most common type of neoplasm (43.2%) and the lung being the most common primary site (40.5%).
SMPMNS patients without metastases had a longer overall survival rate than those with metastases. PET/CT and conventional imaging (CI) showed poor consistency in diagnostic accuracy and diagnosis of primary lesions (diagnosed and misdiagnosed), however, the diagnostic performance of PET/CT was better than that of CI. In the diagnosis of metastases, the patient-based sensitivity, speciﬁcity, and accuracy of PET/CT were 100.0%, 81.8%, and 89.2%, respectively, while those of CI were 73.3%, 100.0%, 89.2%, respectively. The sensitivity and speciﬁcity values were signiﬁcantly different, with PET/CT having higher sensitivity (p = 0.02) and CI showing higher speciﬁcity (p = 0.02).
The authors concluded that 18F-FDG PET/CT, when combined with clinical features, can improve the diagnostic performance of SMPMNS and can reveal more primary tumors and metastatic lesions. 18F-FDG PET/CT is helpful to increasing the awareness of clinicians regarding SMPMNS and reduces the number of missed diagnosis and misdiagnosis.