68Ga-NODAGA-Exendin-4 PET/CT Findings in a Case of Metastatic Insulinoma With Refractory Hypoglycemia Controlled by 90Y Transarterial Radioembolization.

ABSTRACT: Metastatic insulinomas can cause recurrent hypoglycemia requiring continuous IV glucose infusion. Various medical and chemotherapeutic treatment options are used to reduce the patient's risk of death due to hypoglycemia. Treatment-resistant hepatic metastatic insulinomas may benefit clinically from 90Y transarterial radioembolization therapy. In this case, we present a case of liver metastatic insulinoma that achieved clinical improvement after 2 cycles of 90Y microspheres transarterial radioembolization, and the presence of active metastases was demonstrated with 68Ga-NODAGA-exendin-4 PET/CT imaging.

Bilateral Adrenal Metastasis of Prostatic Adenocarcinoma on 68 Ga-PSMA PET/CT Imaging.

ABSTRACT: An 84-year-old man with prostate adenocarcinoma underwent 68 Ga-PSMA PET/CT due to PSA recurrence. Foci of 68 Ga-PSMA uptake were observed in bilateral adrenal glands. Adrenal MRI showed metastasis only in the left adrenal gland. Metastatic 68 Ga-PSMA uptake was also observed in the mediastinum and bone. Enzalutamide treatment was started. Follow-up 68 Ga-PSMA PET/CT scan showed regression in both adrenal gland metastases and other metastases.

The potential role of 68Ga-FAPI-04 PET/CT for screening malignancy in suspected colonic lesions.

AIM: Benign colonic lesions like tubular adenoma may show intense uptake on F-18-FDG PET/CT and can be mistaken for malignancy. In this study, we evaluated the role of 68Ga-FAPI-04 PET/CT for discriminating the benign and malignant colonic lesions. METHODS: Forty patients with diagnosis of colorectal cancer who had undergone 18F-FDG-PET/CT and 68Ga-FAPI-04 PET/CT for initial staging were retrospectively analyzed. The unexpected foci of uptake in colon on 18F-FDG PET/CT were compared with 68Ga-FAPI-04 PET/CT with lesion and background SUVmax. RESULTS: The primary colorectal lesion SUVmax on both PET/CTs was similar. A total of 9 incidental colon lesions in 7 patients were detected showing intense 18F-FDG uptake and no 68Ga-FAPI-04 uptake. All of the lesions were consistent with tubular adenoma histopathologically. CONCLUSION: 68Ga-FAPI PET/CT may have a crucial role for discrimination of benign and malignant colonic lesions and avoid the unnecessary interventions and extended surgeries in patients with colorectal cancer.

Cutaneous Metastase of Rectal Neuroendocrine Carcinoma Revealed on 18F-FDG PET/CT.

Rectal neuroendocrine carcinomas constitute <1% of all neuroendocrine carcinomas and <1% of all gastrointestinal tract malignancies. Cutaneous metastases of rectal neuroendocrine carcinoma are rarer than visceral metastases. We represent a 71-year-old man who was diagnosed with neuroendocrine tumor grade 3 originating from the rectum 1 year ago. He was referred for 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography for restaging after 6 cycles of chemotherapy and radiotherapy. Intensely increased 18F-FDG uptake in the right cutaneous inguinal region was consistent with neuroendocrine carcinoma metastasis with biopsy from the same region.

68Ga-PSMA and 68Ga-FAPI-04 PET/CT Findings With 18F-FDG PET/CT in a Patient With Recurrent Prostate Cancer.

ABSTRACT: A 79-year-old man with prostate cancer was evaluated with 68Ga-prostate-specific membrane antigen (PSMA), 68Ga-FAPI-04, and 18F-FDG PET/CT scans since a rise in prostate-specific antigen was seen at last control while receiving chemotherapy. Abnormal FDG uptakes were observed in the tumoral areas of the left half of the prostate and walls of the bladder, although PSMA and FAPI activity were absent or lower in the relevant tumoral areas. Restaging 68Ga-PSMA and 18F-FDG PET/CT scans were obtained on the patient whose progression continued after transurethral tumor resection. Herein, we present a case proving intraindividual tumor heterogeneity in prostate cancer underwent PET/CT imaging with 3 different radiopharmaceuticals.

Gallbladder Metastasis From Renal Cell Carcinoma Revealed With 18 F-FDG PET/CT.

ABSTRACT: Gallbladder metastasis from renal cell carcinoma is a rare condition. To our knowledge, only 1 case has been reported with 18 F-FDG PET/CT findings. Herein, we report the case of a 53-year-old man with renal cell carcinoma, having gallbladder metastasis revealed with restaging 18 F-FDG PET/CT.

68 Ga-DOTATATE Uptake in Well-Differentiated Neuroendocrine Tumor of the External Auditory Canal.

ABSTRACT: A 38-year-old woman presented with a 4-month history of left-sided otalgia and otorrhea. Otoscopy revealed a mass in the left external auditory canal causing obliteration. A biopsy was taken, and the diagnosis was consistent with a well-differentiated neuroendocrine tumor. The patient was referred to our department for staging with 68 Ga-DOTATATE PET/CT. Increased radiopharmaceutical uptake was observed in the primary tumor and metastatic lymph nodes.

Peritoneal Tuberculosis Mimicking Peritoneal Carcinomatosis on 68 Ga-FAPI-04 and 18 F-FDG PET/CT.

ABSTRACT: We report a case of tuberculosis peritonitis in a 26-year-old woman who presented with abdominal pain, fatigue, and weight loss for the last 4 months. Abdominal US and CT demonstrated intra-abdominal massive ascites, misty mesentery, and diffuse peritoneal thickening. In addition, 3 nodular lesions were detected in the right lung. 18 F-FDG PET/CT showed hypermetabolism in lung nodules, mesenteric area, peritoneal thickening, and ascites. 68 Ga-FAPI-04 (fibroblast activation protein-specific inhibitor) PET/CT imaging was also performed; high uptakes were detected in the same regions of 18 F-FDG PET/CT. Tuberculosis diagnosis was made after histopathological examination of wedge resection of the right lung.

18F-FDG PET/CT Findings in HIV-Positive Patient With Primary Pancreas Lymphoma and CMV Pancreatitis.

ABSTRACT: A 35-year-old HIV-positive man with abdominal pain was referred to 18F-FDG PET/CT for metabolic characterization of mass in pancreas. PET/CT images showed intense FDG uptake in head of the pancreas, as well as diffuse moderate uptake throughout body and tail of the pancreas. Histopathological results revealed Epstein-Barr virus (EBV) associated large B-cell lymphoma and pancreatitis caused by cytomegalovirus.

Sigmoid Colon Carcinoma Presenting in Inguinoscrotal Hernia With FDG PET/CT.

ABSTRACT: Primary carcinoma of the sigmoid colon in an inguinal hernia is a rare condition. We present a 79-year-old man diagnosed with sigmoid colon carcinoma referred to 18F-FDG PET/CT for staging. PET/CT showed the primary lesion in the inguinal hernia into scrotum.