Neuroendocrine neoplasms (NEN) are rare tumors arising from neuroendocrine cells. NEN are ideally suited for a theragnostic approach due to their specific expression of somatostatin receptors (SSTR). SSTR imaging of NEN dates back to the 1980s, but has evolved recently due to the introduction of more sensitive SSTR PET radiotracers.
View Article and Find Full Text PDFPeptide receptor radionuclide therapy (PRRT) has become mainstream therapy of metastatic neuroendocrine tumors not controlled by somatostatin analog therapy. Currently, beta particle-emitting radiopharmaceuticals are the mainstay of PRRT. Alpha particle-emitting radiopharmaceuticals have a theoretic advantage over beta emitters in terms of improved therapeutic efficacy due to higher cancer cell death and lower nontarget tissue radiation-induced adverse events due to shorter path length of alpha particles.
View Article and Find Full Text PDFThe checkpoint immunotherapeutic pembrolizumab induces responses in a small minority of patients with metastatic castration-resistant prostate cancer (mCRPC). Radium-223 (R223) may increase immunogenicity of bone metastases and increase pembrolizumab (P) activity. In a randomized phase II study, we assessed the effect of R223+P compared with R223 on tumor immune infiltration, safety, and clinical outcomes in patients with mCRPC.
View Article and Find Full Text PDFPurpose: The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part I of a three-part series focusing on treatment decision-making at the time of suspected biochemical recurrence (BCR) after radical prostatectomy (RP). Please refer to Part II for discussion of treatment delivery for non-metastatic BCR after RP and Part III for discussion of evaluation and management of recurrence after radiotherapy (RT) and focal therapy, regional recurrence, and oligometastasis.
View Article and Find Full Text PDFPurpose: The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part III of a three-part series focusing on evaluation and management of suspected non-metastatic recurrence after radiotherapy (RT) and focal therapy, evaluation and management of regional recurrence, management for molecular imaging metastatic recurrence, and future directions. Please refer to Part I for discussion of treatment decision-making and Part II for discussion of treatment delivery for non-metastatic biochemical recurrence (BCR) after radical prostatectomy (RP).
View Article and Find Full Text PDFPurpose: The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part II of a three-part series focusing on treatment delivery for non-metastatic biochemical recurrence (BCR) after primary radical prostatectomy (RP). Please refer to Part I for discussion of treatment decision-making and Part III for discussion of evaluation and management of recurrence after radiotherapy (RT) and focal therapy, regional recurrence, and oligometastasis.
View Article and Find Full Text PDFThe clinical use and prognostic value of interim FDG-PET/CT (iPET/CT), which is performed after treatment initiation but prior to its completion, varies by lymphoma subtype. Evidence supporting the prognostic value of iPET/CT is more robust for classical Hodgkin lymphoma (cHL), and in this lymphoma subtype, response-adapted treatment approaches guided by iPET/CT are a widely used standard of care for first-line therapy. The data supporting use of iPET/CT among patients with non-Hodgkin lymphoma (NHL) is less well-established, but failure to achieve complete metabolic response on iPET/CT is generally considered a poor prognostic factor with likely consequences for progression free survival.
View Article and Find Full Text PDFBackground: 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 (SUV) is associated with decreased survival.
View Article and Find Full Text PDFRationale And Objectives: To understand the current state of radiology residents' exposure to nuclear medicine and molecular imaging (NM/MI), determine key factors that may attract more trainees into the field, and identify differentiating aspects between those specializing in NM/MI and those who are not.
Materials And Methods: An anonymous web-based survey was sent to contacts at all diagnostic radiology residency programs in the United States for dissemination to their residents, collecting information about trainees' NM/MI exposure during residency and factors that may attract them to NM/MI.
Results: A total of 198 trainees responded to the survey, 34 of whom plan on pursuing a career in NM/MI.
Background/aims: Gastric emptying scintigraphy is commonly performed to assess for dysmotility. A standardized meal with associated threshold criteria was established in 2000 to enable robust interpretation. However, no guidance is available to interpret results when patients do not ingest the entire meal.
View Article and Find Full Text PDFRadiation therapy is an integral component of the treatment of breast cancer. The indications and type of radiation therapy vary depending on disease invasiveness and stage. Imaging is the cornerstone for radiation therapy planning.
View Article and Find Full Text PDFBRAF-targeted kinase inhibitors (KIs) are used to treat malignancies including BRAF-mutant non-small cell lung cancer, colorectal cancer, anaplastic thyroid cancer, and, most prominently, melanoma. However, KI selection criteria in patients remain unclear, as are pharmacokinetic/pharmacodynamic (PK/PD) mechanisms that may limit context-dependent efficacy and differentiate related drugs. To address this issue, we imaged mouse models of BRAF-mutant cancers, fluorescent KI tracers, and unlabeled drug to calibrate in silico spatial PK/PD models.
View Article and Find Full Text PDFImportance: Neoadjuvant immunotherapy is a novel approach with the potential to improve outcomes for patients with oral cavity squamous cell cancer (OCSCC). Adverse events of varying severity are reported with immunotherapy, and a biomarker to predict response would be clinically useful to avoid toxic effects in those unlikely to benefit.
Objective: To correlate changes on fluoro-[18F]-deoxy-2-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) scans with primary tumor pathologic response and immunologic biomarkers in patients with OCSCC receiving neoadjuvant immunotherapy.
A 67-year-old man with metastatic lung adenocarcinoma was initially treated with whole-brain radiotherapy for intracranial metastases, followed by chemotherapy and pembrolizumab. After completing 2 years of systemic therapy, the primary right lung lesion was biopsy-proven to have residual adenocarcinoma, which was then treated with radiation (6000 cGy in 15 fractions). Follow-up serial FDG PET/CT showed radiation fibrosis.
View Article and Find Full Text PDFHematologic malignancies are a broad category of cancers arising from the lymphoid and myeloid cell lines. The 2016 World Health Organization classification system incorporated molecular markers as part of the diagnostic criteria and includes more than 100 subtypes. This article focuses on the subtypes for which imaging with positron emission tomography/computed tomography (PET/CT) has become an integral component of the patient's evaluation, that is, lymphoma and multiple myeloma.
View Article and Find Full Text PDFPurpose: We prospectively evaluated the feasibility of SPECT-CT/planar organ dosimetry-based radiation dose escalation radioimmunotherapy in patients with recurrent non-Hodgkin's lymphoma using the theranostic pair of In and Y anti-CD20 ibritumomab tiuxetan (Zevalin) at myeloablative radiation-absorbed doses with autologous stem cell support. We also assessed acute non-hematopoietic toxicity and early tumor response in this two-center outpatient study.
Methods: 24 patients with CD20-positive relapsed or refractory rituximab-sensitive, low-grade, mantle cell, or diffuse large-cell NHL, with normal organ function, platelet counts > 75,000/mm, and <35% tumor involvement in the marrow were treated with Rituximab (375 mg/m) weekly for 4 consecutive weeks, then one dose of cyclophosphamide 2.
The appropriate selection of patients to undergo hematopoietic stem cell transplant (HSCT) is critical due to the risk of treatment-related morbidity and mortality. The prognostic value of FDG-PET/CT in response assessment in hematologic malignancies is well-established and has led to numerous investigations into the role of FDG-PET/CT in the evaluation of patients in the setting of HSCT. This article discusses the most common indications for autologous stem cell transplant (autoSCT) in which FDG-PET/CT has been evaluated, including for lymphoma and multiple myeloma.
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