Hepatosplenic Tuberculosis on Pretherapy and Posttherapy FDG PET/CT

Solitary Accessory Spleen-Like Metastasis Coexisted With Splenic Infarction Reveled on 18F-FDG PET/CT in a Hepatocellular Carcinoma Patient

ABSTRACT

Solitary parasplenic metastatic carcinoma may be misinterpreted as accessory spleen on CT images. In addition, elevated FDG uptake in the spleen may also mimic metastasis in patient with a history of carcinoma. Here we present a case of parasplenic metastasis coexisted with splenic infarction reveled on 18F-FDG PET/CT in a 51-year-old man with history of hepatocellular carcinoma.

The utility of F-18 FDG PET/CT for diagnosis and response evaluation of hepatosplenic tuberculosis

A 77-year-old woman underwent F-18 FDG PET/CT for evaluation of fever focus. Diffuse and intense hepatosplenic uptake was noted and lymphoma or tuberculosis was proposed. Liver biopsy revealed chronic granulomatous inflammation with Langerhans-type giant cells and necrosis. A follow-up PET/CT after anti-tuberculosis treatment revealed that the hepatosplenic uptake had resolved.

Primary Solitary Tuberculosis in the Hepatic Round Ligament Detected by 68Ga-FAPI PET/CT

ABSTRACT

A 45-year-old woman recently complained of abdominal pain, poor appetite, and weight loss. Her serum ferritin, CA199, and CA242 levels were elevated. 68Ga-FAPI PET/CT revealed a subcapsular mass in the liver, which showed a significant FAPI uptake without other abnormal activity. Postoperative pathological examination confirmed tuberculosis in the hepatic round ligament.

PET/CT Variants and Pitfalls in Liver, Biliary Tract, Gallbladder and Pancreas

A wide variety of pathological anomalies may occur in the liver, biliary system, and pancreas. It is a necessity to use many different imaging techniques in order to distinguish such varied pathologies, especially those from malignant processes. Positron Emission Tomography/Computed Tomography (PET/CT) is an imaging method that has proven its diagnostic value in oncology and can be used for different clinical purposes. Fluoro-18 fluoro-2-deoxy-D-glucose has a wide range of uses as a dominant radiopharmaceutical in routine molecular imaging, however, molecular imaging has started to play a more important role in personalized cancer treatment in recent years with new Fluoro-18 and Gallium-68 labeled tracers. Although molecular imaging has a strong diagnostic effect, the surprises and pitfalls of molecular imaging can lead us to unexpected and misleading results. Prior to PET/CT analysis and reporting, information about possible technical and physiological pitfalls, normal histological features of tissues, inflammatory pathologies, specific clinical features of the case, treatment-related complications and past treatments should be evaluated in advance to avoid misinterpretation. In this review, the physiological and pathophysiological variants as well as pitfalls encountered in PET/CT imaging of the liver, biliary tract, gallbladder, and pancreas will be examined. Other benign and malignant pathologies that have been reported to date and that have led to incorrect evaluation will be listed. It is expected that the devices, software, and artificial intelligence applications that will be developed in the near future will enable much more effective and faster imaging that will reduce the potential causes of error. However, as a result of the dynamic and evolving structure of the information obtained by molecular imaging, the inclusion of the newly developed radiopharmaceuticals in routine practice will continue to carry new potentials as well as new troubles. Although molecular imaging will be the flagship of diagnostic oncology in the 21st century, the correct analysis and interpretation by the physician will continue to form the basis of achieving optimal performance.

18F-FDG PET-CT Diagnosis of Tuberculosis in Celiac Lymph Nodes

The special location of abdominal tuberculosis makes it difficult for biopsy, while its clinical and imaging characteristics make it indistinguishable from tumors. Here, we report a female patient that was initially misdiagnosed with pancreatic cancer, but eventually correctly diagnosed with tuberculosis in the celiac lymph nodes using ¹⁸F-FDG PET–CT. She was 38 years old. Her main complaint was “deep abdominal pain and discomfort for nearly a month”, accompanied by nausea and vomiting. Diagnosis of pancreatic tumors or enlarged lymph nodes was initially made based on CT scan results. Abdominal MRI revealed enlarged lymph nodes. ¹⁸F-FDG PET–CT imaging revealed a soft-tissue mass about 2.8 cm in diameter in the hepatic hilar area with a maximum standardized uptake value (SUV_max) of 9.4, and delayed imaging measured the SUV_max at 12. Enhanced CT showed no vascular envelopment in the mass. Based on these results, the patient was diagnosed with tuberculosis in the celiac lymph nodes. Her tuberculin test was strongly positive. After 5 months of antituberculosis treatment, the mass had reduced to about 1.5 cm in diameter and SUV_max reduced to 8.1, as demonstrated by ¹⁸F-FDG PET–CT imaging. Abdominal lymph-node tuberculosis is easy to misdiagnose, but timely ¹⁸F-FDG PET–CT imaging combined with tuberculin testing may reduce misdiagnosis and mistreatment.