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Solitary pulmonary nodules (SPNs) measuring 8 to 30 mm in diameter require further workup to determine the likelihood of malignancy.

Modern radiotherapy delivers treatment plans optimised on an individual patient level, using CT-based 3D models of patient anatomy. This optimisation is fundamentally based on simple assumptions about the relationship between radiation dose delivered to the cancer (increased dose will increase cancer control) and normal tissue (increased dose will increase rate of side effects). The details of these relationships are still not well understood, especially for radiation-induced toxicity. We propose a convolutional neural network based on multiple instance learning to analyse toxicity relationships for patients receiving pelvic radiotherapy. A dataset comprising of 315 patients were included in this study; with 3D dose distributions, pre-treatment CT scans with annotated abdominal structures, and patient-reported toxicity scores provided for each participant. In addition, we propose a novel mechanism for segregating the attentions over space and dose/imaging features independently for a better understanding of the anatomical distribution of toxicity. Quantitative and qualitative experiments were performed to evaluate the network performance. The proposed network could predict toxicity with 80% accuracy. Attention analysis over space demonstrated that there was a significant association between radiation dose to the anterior and right iliac of the abdomen and patient-reported toxicity. Experimental results showed that the proposed network had outstanding performance for toxicity prediction, localisation and explanation with the ability of generalisation for an unseen dataset.

Background: A systematic literature review of the performance of 18Fluorine-fluciclovine PET/CT for imaging of men with recurrent prostate cancer was performed. Methods: Scientific literature databases (MEDLINE, ScienceDirect and Cochrane Libraries) were searched systematically during Oct 2020 using PRISMA criteria. No limit was put on the date of publication. Prospective studies reporting a patient-level 18F-fluciclovine detection rate (DR) from ≥25 patients with recurrent prostate cancer were sought. Proceedings of relevant meetings held from 2018 through Oct 2020 were searched for abstracts meeting criteria. Results: Searches identified 321 unique articles. In total, nine articles (six papers and three conference abstracts), comprising a total of 850 patients met inclusion criteria. Most studies (n= 6) relied on ASTRO-Phoenix Criteria, EAU-ESTRO-SIOG, and/or ASTRO-AUA guidelines to identify patients with biochemical recurrence. Patients’ PSA levels ranged from 0.02–301.7 ng/mL (median level per study, 0.34–4.10 ng/mL [n= 8]). Approximately 64% of patients had undergone prostatectomy, but three studies focused solely on post-prostatectomy patients. Adherence to imaging protocol guidelines was heterogeneous, with variance seen in administered activity, uptake and scan times. Overall patient-level DR varied between studies from 26% to 83%, with 78% of studies reporting a DR > 50%. DR was proportional to PSA, but even at PSA < 0.5 ng/mL DR of up to 53% were reported. Prostate/bed DR (n= 7) ranged from 18% to 78% and extra-prostatic rates (n= 6) from 8% to 72%. Pelvic node and bone lesion DR ranged from 8% to 47% and 0% to 26%, respectively (n= 5). 18F-Fluciclovine PET/CT was shown to impact patient management and outcomes. Two studies reported 59–63% of patients to have a management change post-scan. A further study showed significant increase in failure-free survival following 18F-fluciclovine-guided compared with conventional imaging-guided radiotherapy planning. Conclusions: 18F-Fluciclovine PET/CT shows good performance in patients with recurrent prostate cancer leading to measurable clinical benefits. Careful adherence to recommended imaging protocols may help optimize DR.

The purpose of these guidelines is to assist specialists in Nuclear Medicine and Radionuclide Radiology in recommending, performing, interpreting and reporting 18F-fluciclovine PET/computed tomography. It should be recognised that adherence to the guidance in this document will not assure an accurate diagnosis or a successful outcome. These guidelines will assist individual departments in the formulation of their own local protocols. The guidelines apply to studies on adults. All that should be expected is that the practitioner will follow a reasonable course of action based on current knowledge, available resources and the needs of the patient in order to deliver effective and safe medical care.

Introduction

MRI–guided radiation therapy for treating pelvic tumors offers superior soft-tissue contrast, improved organ motion visualization, and the potential to image tumor phenotypic characteristics with real-time online adaptation of treatment plans to potentially decrease toxic effects and improve oncologic outcomes.

AbstractBackground:Riedel’s thyroiditis is characterised by chronic inflammatory invasive fibrosclerosis of the thyroid gland, surrounding structures, and extrathyroidal fibrosis. We present a case of Riedel’s thyroiditis associated with nodular fibrosis of the lungs and liver. Case:A 40-year-old woman presented with a 3-month history of neck swelling, difficulty swallowing and breathlessness on exertion. Core biopsy of the goitre revealed dense fibrous tissue with mixed chronic inflammatory cells. A staging computed tomography scan revealed a large thyroid mass encasing the oesophagus and compressing the trachea, multiple bilateral pulmonary nodules with no evidence of lymphadenopathy, and multiple suspicious nodular lesions in the liver. A thorascopic biopsy of a lung lesion in its entirety revealed a hyalinising lung lesion with no evidence of malignancy. Following the introduction of levothyroxine replacement, symptomatic improvement occurred in parallel with improvements in imaging. Conclusion:To our knowledge, this is the first description of Riedel’s thyroiditis presenting with nodular extrathyroidal fibrosis, and which showed resolution following institution of levothyroxine.Copyright © 2012 European Thyroid Association Published by S. Karger AG, Basel

The emergence of hybrid imaging, combining anatomical computed tomography (CT) and functional single-photon emission computed tomography (SPECT), has greatly expanded the armoury available to image disease. Integrated SPECT-CT is a dual-modality technique, which improves the sensitivity and specificity of existing radionuclide studies and enables characterization of equivocal findings detected by conventional imaging. There is a wide range of established and emerging clinical applications for SPECT-CT, which were reviewed in detail at a symposium organized by the British Institute of Radiology in March 2012. A series of articles were commissioned as an adjunct to the symposium and to raise awareness of the clinical utility of this technique. The focus of this article is on less commonly used and emerging clinical applications of hybrid SPECT-CT in a spectrum of benign and malignant conditions. The article will illustrate the incremental value of the technique in a variety of clinical applications.

Background:Riedel’s thyroiditis is characterised by chronic inflammatory invasive fibrosclerosis of the thyroid gland, surrounding structures, and extrathyroidal fibrosis. We present a case of Riedel’s thyroiditis associated with nodular fibrosis of the lungs and liver. Case:A 40-year-old woman presented with a 3-month history of neck swelling, difficulty swallowing and breathlessness on exertion. Core biopsy of the goitre revealed dense fibrous tissue with mixed chronic inflammatory cells. A staging computed tomography scan revealed a large thyroid mass encasing the oesophagus and compressing the trachea, multiple bilateral pulmonary nodules with no evidence of lymphadenopathy, and multiple suspicious nodular lesions in the liver. A thorascopic biopsy of a lung lesion in its entirety revealed a hyalinising lung lesion with no evidence of malignancy. Following the introduction of levothyroxine replacement, symptomatic improvement occurred in parallel with improvements in imaging. Conclusion:To our knowledge, this is the first description of Riedel’s thyroiditis presenting with nodular extrathyroidal fibrosis, and which showed resolution following institution of levothyroxine.

Multiple endocrine neoplasia (MEN) is characterized by the occurrence of two or more tumors that may be associated with hyperfunction and malignancy. MEN is caused by genetic defects, and two major types, MEN 1 and MEN 2, are recognized. Each type is characterized by the development of tumors within specific endocrine organs. A multidisciplinary approach involving cooperation between endocrinologists, surgeons, oncologists, and radiologists is pivotal for optimizing patient treatment. Imaging plays a vital role in the diagnosis and management of the disease. To contribute effectively, however, the radiologist must understand the range of anatomic and functional imaging modalities used in the assessment of endocrine disorders. In addition, knowledge of the optimal techniques for evaluating the pituitary, thyroid, parathyroid, pancreatic, adrenal, and foregut carcinoid tumors that occur in these MEN syndromes is essential. Finally, an understanding of the spectrum of disease and of the manifestations of each component is crucial for accurate detection, staging, and surveillance in this diverse patient group. © RSNA, 2006