Fig. 1

a Whole body FDG PET (MIP, maximum intensity projection image, head to mid-thigh) image of a 48-year-old lady with headache and PUO. The image shows FDG avid “string of pearls sign” due to extensive supradiaphragmatic nodal lesions (arrows depict bilateral cervical, supraclavicular, pectoral, and axillary nodes) in a case of Kikuchi disease with associated meningitis. Based on PETMR, nodal biopsy, and CSF findings, the patient was appropriately managed. b FDG PET (MIP image) findings in a 61-year-old male with intermittent low-grade fever, associated generalized itching, nodular swellings in extremities, and raised inflammatory markers. Whole body FDG PETCT from head to toe was performed. The images revealed FDG avid nodal arrangement [“string of pearls sign”] in the neck and chest due to bilateral cervical, axillary, pectoral nodal involvement. There were extensive FDG avid supra and infradiaphragmatic nodal lesions along with FDG extensive cutaneous and subcutaneous nodular lesions scattered all over the body including the extremities. Mantle cell lymphoma was histologically confirmed, and the patient was subjected to chemotherapy. Thus, “string of pearls sign” is a non-specific PET finding and can be present in nodal disease of diverse etiologies