Purpose: Patients with recurrent high-grade glioma have poor prognosis and limited treatment options. This pilot study evaluated the feasibility and potential clinical benefit of 177 Lu-PSMA therapy in this patient population. Patients and Methods: Eligible patients were selected for treatment based on positive 68 Ga-PSMA-PET findings. 177 Lu-PSMA (7.4 GBq/200 mCi) was administered at 6–8-week intervals and continued as long as well-tolerated. The safety, tolerability, and efficacy of 177 Lu-PSMA were assessed in each treatment cycle using PET/MRI, SPECT/CT, blood tests, neurological tests, and patient-reported outcome measures. Results: Ten patients were enrolled (WHO grade 4 glioblastoma, n=6; WHO grade 4 astrocytoma, n=1; WHO grade 3 astrocytoma, n=3). 68 Ga-PSMA-PET before treatment demonstrated tumor uptake in 9 patients (median SUV max : 6.4, IQR: 4.2–9.0). Six patients received treatment (20 cycles total; range: 1–7 per patient). Median absorbed dose per cycle was 0.9 Gy (IQR: 0.8–1.1) for tumors, 2.6 Gy (IQR: 1.9–3.2) for kidneys, and 1.7 Gy (IQR: 1.5–2.2) for parotid glands. No CTCAE grade 3–4 toxicities occurred. The most common patient-reported symptoms were fatigue, transient xerostomia, and nausea. Median survival from treatment initiation was 187 days (range: 87–756) and the median progression-free survival was 45 days (range: 41–335). MRI (RANO 2.0) demonstrated stable disease in half of the patients during all or part of the treatment course. Conclusions: 177 Lu-PSMA therapy was feasible and well-tolerated. Radiologic stabilization was observed in a subset of patients, but strategies to increase tumor dose delivery may be needed to improve efficacy.
Solitary ectopic insulinomas without concurrent pancreatic or gastrointestinal lesions are exceedingly rare. We report the 18 F-NOTA-exendin-4 PET/CT findings of a solitary ectopic insulinoma in a 68-year-old woman with a 10-year history of recurrent hypoglycemic syncope. Endogenous hyperinsulinemia was confirmed, but conventional imaging and laparoscopic pancreatic exploration were negative. PET/CT revealed a solitary intense focus in the para-abdominal aortic region. Surgical resection confirmed a solitary ectopic insulinoma, and postoperative hypoglycemia resolved. This case highlights the value of 18 F-NOTA-exendin-4 PET/CT in identifying occult solitary ectopic insulinomas when conventional imaging and surgical exploration are unrevealing, enabling curative resection.
68 Ga-PSMA-11-PET/CT is widely used for staging prostate cancer but may also detect nonprostatic malignancies owing to prostate-specific membrane antigen (PSMA) expression in tumor neovasculature. Here, we report a case of a newly diagnosed high-risk prostate adenocarcinoma that underwent staging 68 Ga-PSMA-11-PET/CT. In addition to the primary prostatic lesion, PSMA-expressing lesions were identified in the sternum and right thyroid lobe. While skeletal involvement was initially presumed metastatic prostate cancer, further evaluation revealed follicular variant papillary thyroid carcinoma. This case highlights an important diagnostic pitfall and demonstrates the value of PSMA-PET/CT in uncovering clinically occult synchronous malignancies.
This report highlights the potential role of [ 68 Ga]Ga-FAP-2286 PET/CT in the early detection of active tumor recurrence in a 64-year-old woman with glioblastoma multiforme (IDH-wild type, WHO grade IV), preceding definitive radiologic evidence of disease progression. Following confirmation of recurrence, the patient underwent combined chemotherapy and [ 177 Lu]Lu-FAP-2286 radioligand therapy, resulting in a favorable partial molecular and anatomic response as demonstrated by serial PET/CT and MRI examinations. This case illustrates the potential theranostic value of FAP-targeted imaging and radionuclide therapy in the management of recurrent glioblastoma.
Purpose: This study was designed to investigate the detection rate and tumor uptake of 18 F-AlF-NOTA-De-FAPI PET/CT in newly diagnosed high-risk prostate cancer (PCa), compared with 68 Ga-PSMA-11 and 18 F-FDG PET/CT. Patients and Methods: This study enrolled 48 patients with biopsy-diagnosed, treatment-naive high-risk PCa who underwent 18 F-AlF-NOTA-De-FAPI, 68 Ga-PSMA-11, and 18 F-FDG PET/CT between April and December 2024. A head-to-head comparison of detection rate and tumor uptake was performed among the 3 tracers. In addition, 18 F-AlF-NOTA-De-FAPI and 68 Ga-PSMA-11 dual-tracer PET was used to characterize the imaging phenotypes of each lesion and interlesional heterogeneity. Results: A total of 477 lesions were detected by the 3 PET tracers. 68 Ga-PSMA-11 exhibited the highest overall detection rate (96.4%), followed by 18 F-AlF-NOTA-De-FAPI (81.1%) and 18 F-FDG (66.0%). A total of 17 68 Ga-PSMA-11-negative lesions were identified in 8 patients, all of which were detected by 18 F-AlF-NOTA-De-FAPI, whereas only 12 were detected by 18 F-FDG. Combined 68 Ga-PSMA-11 and 18 F-AlF-NOTA-De-FAPI PET identified all lesions detected by triple-tracer PET. Based on relative tracer dominance of dual-tracer PET, patients were classified as PSMA-dominant (n=23), FAPI-dominant (n=5), or mixed phenotype (n=20). The mixed phenotype with marked interlesional heterogeneity might be associated with more advanced clinical characteristics, with a higher proportion of metastatic disease and a greater metastatic burden. Conclusions: 18 F-AlF-NOTA-De-FAPI is a promising PET tracer for newly diagnosed high-risk PCa. It may improve the detection rate of 68 Ga-PSMA-11-negative lesions and provide complementary information that could reflect interlesional heterogeneity. The clinical value of combining 18 F-AlF-NOTA-De-FAPI and 68 Ga-PSMA-11 PET requires further validation in larger prospective cohorts.
