FDG–PET findings associated with various medical procedures and treatments

Abstract

Abstract[18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) is a well-established modality with high sensitivity for the diagnosis and staging of oncologic patients. FDG is taken up by the glucose transporter of the cell membrane and becomes trapped within the cell. In addition to malignant neoplasms, active inflammatory lesions and some kinds of benign tumors also accumulate FDG. Moreover, the degree of uptake into normal organs and tissues depends on various physiological conditions, which is affected by various medical procedures, treatments, and drugs. To avoid misleading interpretations, it is important to recognize possible situations of unexpected abnormal accumulation that mimic tumor lesions. In this review, we present various FDG findings associated with surgical or medical procedures and treatments. Some findings reflect the expected physiological reaction to treatment, and some show inflammation due to prior procedures. Occasionally, FDG–PET visualizes other disorders that are unrelated to the malignancy, which may be associated with the adverse effects of certain drugs that the patient is taking. Careful review of medical records and detailed interviews of patients are thus necessary.

Examination of iatrogenic FDG accumulation after COVID-19 vaccination

“…Following vaccine injection into the deltoid muscle (DM), a physiological immunogenic response occurs, leading to reactive ipsilateral axillary lymphadenopathy (2). 18 F-uorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) plays a critical role in diagnosing and accurately staging various types of cancers as well as in monitoring therapy response (3). Although accurate nodal staging is advantageous, reactive lymph nodes due to in ammation can cause false-positive results in FDG-PET/CT assessments (4,5).…”

Diffuse bone marrow uptake on 18F-fluorodeoxyglucose positron emission tomography/computed tomography with copper-deficiency anemia

“…Growth factors, such as granulocyte colony-stimulating factor and erythropoietin, have been documented to induce such a pattern [ 5 , 6 ]. Similarly, bone marrow recovery following chemotherapy-induced hypoplasia or systemic inflammation can enhance the uptake [ 7 , 8 ]. While this patient received erythropoietin for anemia associated with chronic renal failure, its administration did not appear to influence 18 F-FDG uptake, as it resolved despite increasing erythropoietin doses.…”

Common and Uncommon Mimics of Thoracic Malignancy on PET/CT: Part 2—Pearls and Pitfalls of Lung Parenchyma and Mediastinum

“…Misinterpretations may lead to prolongation of chemotherapy or unnecessary therapy, biopsy, needle aspiration, or thymectomy (Figure 12). 22,23…”

“…Misinterpretations may lead to prolongation of chemotherapy or unnecessary therapy, biopsy, needle aspiration, or thymectomy (Figure 12). 22,23 Granulomatous lymphadenitis is a benign cause of mediastinal lymphadenopathy. This may be caused by infections such as fungal and mycobacterial infections and sarcoidosis.…”