Hutch diverticulum (HD) is a rare congenital condition characterized by the herniation of the bladder’s mucosa and submucosa through the detrusor muscle fibers, encountered more commonly in children. An association between HD and situs inversus totalis (SIT) in an elderly patient has not been reported previously in the literature. We present the case of a 70-year-old male referred for routine bone scintigraphy as part of staging for lung carcinoma; thoraco-abdomino-pelvic computed tomography confirmed the staging and revealed a total transposition of the thoracic and abdominal organs, confirming SIT. This case highlights the exceptional association of HD and SIT, which was discovered incidentally in an elderly patient during metastatic staging for lung cancer. It underscores the importance of careful interpretation of scintigraphic findings, particularly when unusual radiotracer uptake is observed.
Approximately 85-90% of all rhabdomyosarcoma (RMS) cases occur in children and adolescents. In adults, RMS accounts for only 2-5% of all soft tissue sarcomas. The annual incidence in adults is 0.3-0.5 per 1,000,000 and is classified as a "very rare tumor." More than 95% of RMSs are extragastric. Primary gastric RMS is reported extremely rarely in adults, and the estimated incidence is <0.01/1,000,000/year. This rate is <0.01% of all gastric malignancies and <1% of all adult RMSs. We report the 18F-fluorodeoxyglucose positron emission tomography/computed tomography findings in an adult with primary gastric alveolar RMS, highlighting the metabolic characteristics of this extraordinarily rare malignancy.
Fat necrosis, a benign postoperative process related to tissue injury and repair, may demonstrate variable findings on functional imaging. We report a case of postoperative fat necrosis following pancreaticoduodenectomy showing intense 68Ga-FAPI uptake in the absence of significant 18F-fluorodeoxyglucose (18F-FDG) avidity. Surveillance 18F-FDG positron emission tomography/computed tomography (18F-FDG PET/CT) demonstrated only mild activity within the surgical bed maximum standard uptake value (SUVmax 2.4), while subsequent 68Ga-FAPI PET/CT revealed marked uptake corresponding to fat necrosis SUVmax 9.9, consistent with pronounced fibroblast activation during postoperative healing. Additionally, a benign left adrenal adenoma showed low 18F-FDG uptake and only minimal 68Ga-FAPI avidity (SUVmax 2.3), reflecting minimal stromal activation. This case highlights the tracer discordance between 18F-FDG and 68Ga-FAPI in fat necrosis and underscores the importance of correlating 68Ga-FAPI findings with surgical history and anatomic imaging to ensure accurate interpretation.
Dementia in individuals with Down syndrome (DS) is the leading cause of early-onset cognitive decline occurring before the age of 50. However, establishing an accurate diagnosis remains particularly challenging due to pre-existing intellectual disability, variability in baseline cognitive function, and the limited reliability of standard neuropsychological assessments. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) plays a critical role in identifying underlying neurodegenerative processes and supporting the diagnosis. We present a case of DS with multiple known and unknown pathologies identified on brain 18F-FDG PET and a confirmed diagnosis of early-onset mild Alzheimer's disease.
Cavernous sinus metastasis from follicular thyroid carcinoma (FTC) is exceedingly rare and typically indicates advanced, radioiodine-refractory disease. We report a 37-year-old man with minimally invasive FTC who was treated with total thyroidectomy, neck dissection, and cumulative radioiodine therapy totaling 720 mCi for persistent iodine-avid disease. Four years later, he developed progressive left-sided palsies of cranial nerves III, IV, and VI. Imaging revealed a cavernous sinus mass with orbital apex extension and perineural spread. Serum thyroglobulin was markedly elevated (>500 ng/mL), whereas diagnostic radioiodine scintigraphy demonstrated no uptake, a finding consistent with dedifferentiated disease. Biopsy confirmed metastatic FTC. The patient received external beam radiotherapy and systemic therapy with lenvatinib; however, the disease progressed, and he died 16 months after the diagnosis of cavernous sinus metastasis. This case highlights the aggressive potential of FTC, the limitations of radioiodine imaging in dedifferentiated disease, and the poor prognosis associated with skull-base metastases despite multimodal therapy.
