Vicarious excretion of 99mTc-pyrophosphate in the gallbladder.

Vicarious excretion of tracer and contrast media is a known phenomenon and is not fully understood [1,2]. We report a case of unexpected vicarious excretion of 99mTc-pyrophosphate in the gallbladder seen on a scan performed to evaluate suspected cardiac amyloidosis, which is the first report of this phenomenon to the best of our knowledge.

Widespread Reactive Lymphatic and Splenic FDG Avidity After mRNA COVID Vaccination.

ABSTRACT: A 75-year-old woman with history of metastatic lung adenocarcinoma in remission develops new widespread FDG-avid lymphadenopathy in the neck, chest, abdomen, and pelvis on surveillance PET/CT, as well as intense FDG uptake in the spleen, without evidence of local recurrence. Short-term follow-up PET demonstrates near-complete resolution of FDG-avid lymphatic and splenic FDG avidity without interval change in management. Further history reveals that the patient received her fifth dose of COVID mRNA vaccine 6 days before the abnormal PET. Although unilateral axillary adenopathy after COVID vaccination is well-recognized, this widespread symmetric lymphatic and splenic FDG avidity is a significantly rarer phenomenon.

Renal Collision Tumor: A Case of Small Cell Lung Cancer Metastasis to Renal Angiomyolipoma.

ABSTRACT: A 68-year-old woman presented with chest pain and shortness of breath. Imaging revealed a left hilar mass biopsy-proven as small cell cancer. Concurrently, a macroscopic fat-containing renal lesion consistent with an angiomyolipoma was observed. Systemic therapy achieved stability in the lungs and bones, and palliative radiation targeted the left hilum. However, progressive lung disease and brain metastases necessitated stereotactic radiosurgery for brain lesions. Notably, the renal angiomyolipoma exhibited increased soft tissue component and new focal uptake on FDG PET/CT. Biopsy confirmed metastatic small cell lung cancer within the renal lesion. This case highlights a rare occurrence of a renal collision tumor involving small cell cancer and angiomyolipoma.

Hepatic Small Vessel Neoplasm Mimics Prostate Cancer on 18 F-DCFPyl PET/CT.

ABSTRACT: 18 F-DCFPyl is a Food and Drug Administration-approved radiotracer that targets prostate-specific membrane antigen and is used in the detection of recurrent or metastatic prostate cancer. As its use has increased, a growing number of nonprostatic disease entities have been identified that express prostate-specific membrane antigen and can mimic prostate cancer. Thus, the interpreting physician must also consider other variables such as serum prostate-specific antigen levels and the distribution of uptake to avoid an inappropriate diagnosis of metastatic prostate cancer. We describe 18 F-DCFPyl uptake associated with a hepatic small vessel neoplasm, an association previously undescribed in the literature.

Current and upcoming radionuclide therapies in the direction of precision oncology: A narrative review.

As new molecular tracers are identified to target specific receptors, tissue, and tumor types, opportunities arise for the development of both diagnostic tracers and their therapeutic counterparts, termed "theranostics." While diagnostic tracers utilize positron emitters or gamma-emitting radionuclides, their theranostic counterparts are typically bound to beta and alpha emitters, which can deliver specific and localized radiation to targets with minimal collateral damage to uninvolved surrounding structures. This is an exciting time in molecular imaging and therapy and a step towards personalized and precise medicine in which patients who were either without treatment options or not candidates for other therapies now have expanded options, with tangible data showing improved outcomes. This manuscript explores the current state of theranostics, providing background, treatment specifics, and toxicities, and discusses future potential trends.

Higher SUVmax on FDG-PET is associated with shorter survival in adrenocortical carcinoma.

BACKGROUND: Adrenocortical carcinoma (ACC) is an aggressive, rare malignancy. 2-deoxy-2-[18F]-fluoro-d-glucose positron emission tomography (FDG-PET) assesses tumor metabolism and glucose utilization. We hypothesized that higher maximum standard uptake value (SUVmax) is associated with decreased survival. METHODS: We performed a retrospective analysis of patients with ACC. Included patients (n = 26) had an FDG-PET scan available with a documentable SUVmax. Patients were dichotomized into "High" (≥8.4, n = 12) and "Low" (<8.4, n = 14) SUVmax. Univariate analysis and survival analysis were performed to compare groups. RESULTS: Demographics between groups were equivalent. The high SUVmax cohort demonstrated lower survival (median 479 days or 15.7 months) compared to the low group (median 1490 days or 48.6 months, p = .01). Log-Rank curve confirmed differences in survival (p = .007). CONCLUSIONS: Higher SUVmax was associated with significantly worse survival in ACC and may reflect a more aggressive phenotype. FDG-PET may provide clinically useful information to determine prognosis and treatment. Further studies should prospectively evaluate using FDG-PET/CT in ACC.

COVID Lessons Continue: Postvaccination Somatostatin Receptor-Positive Axillary Nodes on DOTATATE Imaging.

ABSTRACT: COVID vaccination has begun in most of the countries. Older population and high-risk groups are prioritized for vaccination. Postvaccination imaging in cancer patients may show effects of the immune response to the vaccine. As such, it is important to know the timing and laterality of the vaccination as the reactive lymph nodes in the ipsilateral axilla can be seen on the imaging. We present a case of DOTATATE-avid nonpathologically enlarged lymph nodes in ipsilateral axilla and linear tracer uptake in the deltoid muscle on a patient imaged for a recent diagnosis of rectal neuroendocrine neoplasm.

Neoadjuvant Nivolumab or Nivolumab Plus Ipilimumab in Untreated Oral Cavity Squamous Cell Carcinoma: A Phase 2 Open-Label Randomized Clinical Trial.

Importance: Novel approaches are needed to improve outcomes in patients with squamous cell carcinoma of the oral cavity. Neoadjuvant immunotherapy given prior to surgery and combining programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) immune checkpoint inhibitors are 2 strategies to enhance antitumor immune responses that could be of benefit. Design, Setting, and Participants: In this randomized phase 2 clinical trial conducted at 1 academic center, 29 patients with untreated squamous cell carcinoma of the oral cavity (≥T2, or clinically node positive) were enrolled between 2016 to 2019. Interventions: Treatment was administered with nivolumab, 3 mg/kg, weeks 1 and 3, or nivolumab and ipilimumab (ipilimumab, 1 mg/kg, given week 1 only). Patients had surgery 3 to 7 days following cycle 2. Main Outcomes and Measures: Safety and volumetric response determined using bidirectional measurements. Secondary end points included pathologic and objective response, progression-free survival (PFS), and overall survival. Multiplex immunofluorescence was used to evaluate primary tumor immune markers. Results: Fourteen patients were randomized to nivolumab (N) and 15 patients to nivolumab/ipilimumab (N+I) (mean [SD] age, 62 [12] years; 18 men [62%] and 11 women [38%]). The most common subsite was oral tongue (n = 16). Baseline clinical staging included patients with T2 (n = 20) or greater (n = 9) T stage and 17 patients (59%) with node-positive disease. Median time from cycle 1 to surgery was 19 days (range, 7-21 days); there were no surgical delays. There were toxic effects at least possibly related to study treatment in 21 patients, including grade 3 to 4 events in 2 (N), and 5 (N+I) patients. One patient died of conditions thought unrelated to study treatment (postoperative flap failure, stroke). There was evidence of response in both the N and N+I arms (volumetric response 50%, 53%; pathologic downstaging 53%, 69%; RECIST response 13%, 38%; and pathologic response 54%, 73%, respectively). Four patients had major/complete pathologic response greater than 90% (N, n = 1; N+I, n = 3). With 14.2 months median follow-up, 1-year progression-free survival was 85% and overall survival was 89%. Conclusions and Relevance: Treatment with N and N+I was feasible prior to surgical resection. We observed promising rates of response in both arms, supporting further neoadjuvant studies with these agents. Trial Registration: ClinicalTrials.gov Identifier: NCT02919683.

Multimodality imaging of endocrine immune related adverse events: a primer for radiologists.

Immune-related endocrine adverse events occur in up to one third of patients treated with immune checkpoint inhibitors. The purpose of this article is to provide a comprehensive review of the multimodality imaging features of the different immune-related endocrine adverse events. In this article, we will introduce the different types of immune checkpoint inhibitors used in clinical practice, and for each endocrine organ affected we will describe the clinical presentation, the multimodality imaging features at presentation and after treatment, and the possible differential diagnosis.

Diffuse Large B-Cell Lymphoma in the Era of Precision Oncology: How Imaging Is Helpful.

Diffuse large B cell lymphoma (DLBCL) is the most common histological subtype of Non-Hodgkin's lymphoma. As treatments continues to evolve, so do imaging strategies, and positron emission tomography (PET) has emerged as the most important imaging tool to guide oncologists in the diagnosis, staging, response assessment, relapse/recurrence detection,and therapeutic decision making of DLBCL. Other imaging modalities including magnetic resonance imaging (MRI), computed tomography (CT), ultrasound, and conventional radiography are also used in the evaluation of lymphoma. MRI is useful for nervous system and musculoskeletal system involvement and is emerging as a radiation free alternative to PET/CT. This article provides a comprehensive review of both the functional and morphological imaging modalities, available in the management of DLBCL.