Clinical Nuclear Medicine最新文献

Purpose: This study aims to evaluate the outcome and renal safety of prostate-specific membrane antigen (PSMA)-radioligand therapy (RLT) in patients with metastatic castration-resistant prostate carcinoma (mCRPC) and preexisting renal impairment.

Methods: Ninety-four patients with preexisting renal impairment were included in this retrospective analysis. Inclusion criterion was a glomerular filtration rate (GFR) of ≤60 mL/min (equivalent to Common Terminology Criteria of Adverse Events [CTCAE] ≥2). Patients underwent either [177Lu]Lu-PSMA-617 RLT exclusively (n = 63) or additionally in augmented manner with [225Ac]Ac-PSMA-617 (n = 31). The median number of administered cycles was 4 (range, 1-16 cycles) with a mean cumulative activity of 29.9 ± 16.3 GBq (range, 6.9-87.2 GBq) [177Lu]Lu-PSMA-617. Main blood parameters of interest were creatinine, cystatin C, and the respective GFR values. Changes in GFR were categorized according to CTCAE v5.0.

Results: In the entire cohort, mean best PSA response was -56.73% ± 45.71%, with 63 of 94 patients (67%) experiencing partial remission. The median progression-free survival and overall survival were 6.7 and 14.1 months, respectively. Under PSMA-RLT, 5 of 94 patients (5.3%) improved to CTCAE grade 0, and 23 of 94 (24.5%) improved to CTCAE grade 1. Three of 94 patients (3.2%) improved from CTCAE grade 3 to grade 2, and only 5 of 94 (5.3%) decreased. The majority (58/94 [61.7%]) of patients stayed stable in terms of CTCAE grading.

Conclusion: PSMA-RLT is an effective and safe treatment in mCRPC patients with preexisting impaired renal function (CTCAE ≥2). In daily clinical practice, patients should not be categorically excluded from enrolment to PSMA-RLT due to renal impairment.

Abstract: A 75-year-old man with a previous history of left nephrectomy for clear cell renal cell carcinoma in remission was underwent 68 Ga-DOTATATE PET/CT imaging for evaluation of pancreatic body lesion. It showed a mass with intense 68 Ga-DOTATATE uptake in the pancreatic corpus. During the follow-up of the patient who did not want to undergo surgery, 18 F-FDG PET/CT scan was performed due to the increase in the size of the mass, and mild FDG uptake was detected in the pancreatic corpus lesion, and histopathological examination was confirmed as renal cell carcinoma metastasis.

Abstract: Primary extraosseous Ewing sarcoma of the nasal cavity is rare. A 17-year-old man underwent 18F-FDG and 68Ga-FAPI-04 PET/CT for a nasal mass. The mass showed avid FDG uptake but weak FAPI uptake. Endoscopic endonasal biopsy confirmed the diagnosis of Ewing sarcoma.

Abstract: A 47-year-old woman, recently diagnosed with breast cancer, underwent staging. A whole-body bone scan revealed an unexpected focal 99mTc-MDP uptake in her right ovary. Extensive literature review suggested various malignant pathologies for this incidental ovarian uptake. Despite inconclusive results from other imaging modalities, the multidisciplinary tumor board recommended right ovarian resection due to a history of abnormal uterine bleeding. The final pathology confirmed an adult-type granulosa cell tumor. Interestingly, subsequent surgery performed for staging purposes found no additional tumor sources. This case highlights the enhanced diagnostic value of hybrid imaging in bone scintigraphy.

Abstract: Intratracheal ectopic thyroid tissue is an extremely rare condition with limited cases reported in the literature. It can be asymptomatic or present with symptoms such as dysphagia, bleeding, dysphonia, dyspnea, and a sensation of a foreign body in the throat, depending on its localization. Due to its various clinical presentations, it poses a diagnostic dilemma. Herein, we aimed to present the contribution of thyroid scintigraphy and SPECT/CT to the diagnosis and management of a case with follicular carcinoma in the orthotopic thyroid gland as well as an ectopic intratracheal thyroid causing cough and airway obstruction mimicking a subglottic mass.

Abstract: Extraosseous manifestations are found in less than 5% of patients with multiple myeloma. They can arise in any tissue, and their presence has been associated with more aggressive disease. We present FDG PET/CT findings of immunoglobulin A κ multiple myeloma with innumerable hypermetabolic right lower extremity lesions of cutaneous and subcutaneous involvement of plasmablastic plasma cell myeloma in a 44-year-old man.

Abstract: Hypertension in younger children is usually secondary to various disorders. A previously healthy 5-year-old girl was diagnosed with stage 2 hypertension. Her personal and family history was noncontributory, and she was normal on physical examination. Blood tests revealed a strongly elevated renin and slightly increased aldosterone, suggesting a renovascular cause. Nevertheless, color Doppler ultrasound, CT, and MR angiography were normal. A DMSA renal scan with and without captopril was performed with results suggestive of a right intrarenal segmental artery branch stenosis, which was corrected with arteriography. A captopril DMSA can be helpful in localizing smaller intrarenal artery branch stenoses.

Abstract: A patient with left upper quadrant breast cancer who had 18F-FDG PET/CT imaging underwent 68Ga-Trivehexin PET/CT. 68Ga-Trivehexin PET/CT showed higher radiotracer accumulation in the primary tumor, left internal mammary lymph nodes, and axillary lymph nodes compared with 18F-FDG PET/CT. However, Trivehexin uptake was not observed in FDG-positive lymph nodes in the mediastinum and left hilar region. Benign cytological findings were noted in the biopsy of the subcarinal lymph node. This case demonstrates that the use of 68Ga-Trivehexin PET/CT in suspicious lymph nodes in areas difficult to biopsy in breast cancer cases can contribute to accurate staging.

Abstract: A 43-year-old woman presented with an anorectal mass at which time excision was performed, and biopsy revealed anorectal mucosal melanoma (AM), anal subtype. Postexcision, 18F-FDG PET/CT identified residual melanoma, confirmed on biopsy. Recurrence was monitored every 3 months using 18F-FDG, which identified a perirectal lymph node 2.5 years later positive for metastatic melanoma. Given the rarity of AM and often delayed diagnosis, patients often present with metastases, resulting in poor prognosis. This unique case of metastatic AM with prolonged survival of 7 years to date supports the implementation of 18F-FDG in the diagnostics and monitoring of AM.

Abstract: In the evolving landscape of precision oncology, this review delineates the role of radiopharmaceuticals targeting the norepinephrine transporter (NET), with a particular focus on the current clinical application of 123I-MIBG diagnostic imaging and 131I-MIBG therapeutics, in particular for pheochromocytoma, neuroblastoma, or paraganglioma. We will also highlight recently introduced 18F-labeled NET targeting imaging radiotracers, which would offer unparalleled resolution, enhanced tumor localization, and staging properties. Complementing these novel second-generation PET agents in a theranostic approach, astatine-211 meta-astatobenzylguanidine (211At-MABG) would leverage the advantages of alpha-particles to selectively target and eradicate NET-expressing tumor cells with minimal off-target effects.