Current Radiopharmaceuticals - Volume 15, Issue 4, 2022

Although metabolic tumor volume (MTV) assessed with pretreatment 18F-FDG PET/CT has shown significant prognostic value across many lymphoma types, it is still not used in clinical practice due to technical concerns and the lack of standardisation. Numerous studies on the prognostic value of MTV in lymphomas have been published in recent years, but there is still no full agreement on the best methodology for MTV calculation. In this paper, we reviewed the methodological aspects of MTV assessment and reported recent works about its impact on outcome in lymphomas, with a focus on Hodgkin lymphoma (HL) and diffuse large B cell lymphoma (DLBCL).

There has been impressive growth in the use of radiopharmaceuticals for therapy, selective toxic payload delivery, and noninvasive diagnostic imaging of disease. The increasing timeframes and costs involved in the discovery and development of new radiopharmaceuticals have driven the development of more efficient strategies for this process. Computer-Aided Drug Design (CADD) methods and Machine Learning (ML) have become more effective over the last two decades for drug and materials discovery and optimization. They are now fast, flexible, and sufficiently accurate to accelerate the discovery of new molecules and materials. Radiopharmaceuticals have also started to benefit from rapid developments in computational methods. Here, we review the types of computational molecular design techniques that have been used for radiopharmaceuticals design. We also provide a thorough examination of success stories in the design of radiopharmaceuticals, and the strengths and weaknesses of the computational methods. We begin by providing a brief overview of therapeutic and diagnostic radiopharmaceuticals and the steps involved in radiopharmaceuticals design and development. We then review the computational design methods used in radiopharmaceutical studies, including molecular mechanics, quantum mechanics, molecular dynamics, molecular docking, pharmacophore modelling, and datadriven ML. Finally, the difficulties and opportunities presented by radiopharmaceutical modelling are highlighted. The review emphasizes the potential of computational design methods to accelerate the production of these very useful clinical radiopharmaceutical agents and aims to raise awareness among radiopharmaceutical researchers about computational modelling and simulation methods that can be of benefit to this field.

Background: Nuclear medicine or diagnostic radiology personnel are always exposed to low-level radiation from radionuclides used in medical diagnostics, which lead to potential biological hazards or effects. Objective: External exposure for workers in two nuclear medicine centers was measured by recruiting 120 patients. Methods: Three nuclear medicine examinations were performed using F18-FDG PET/CT,^99mTc- MDP bones scan, and ^99mTc thyroid scan by a digital radiation dosimeter. Results: The average received accumulative radiation dose for workers was found to be 0.838±0.17, 0.527±0.11, and 0.270±0.05 μSv for F18-FDG PET/CT, ^99mTc-MDP bones scan, and ^99mTc thyroid scan, respectively. The annual effective dose for workers was estimated to be 2.09±0.42, 1.34±0.27, and 0.68±0.14 mSv, respectively. Moreover, the average patient-to-staff dose coefficients were found to be 0.024±0.005, 0.003±0.001, and 0.007±0.002 μSv m²/MBq h for F18- FDG PET/CT, ^99mTc-MDP bones scan, and ^99mTc thyroid scan, respectively. Conclusion: It is clear from the results that the radiation doses received by workers during the nuclear medicine imaging examinations were less than the doses recommended by the International Commission on Radiological Protection (ICRP) for such examinations.

Background: Radiopharmaceuticals are used for the diagnosis, treatment, staging, and follow- up of various diseases. However, there is concern that the ionizing radiation (gamma rays, α and ß particles) may result in the exposure of radiographers with limited knowledge of the principles of radiation protection and safety, raising the risk of cancer induction. Objective: The aim of the study is to investigate the knowledge and level of radiation safety awareness among radiographers at a tertiary hospital. Methods: It is an analytical cross-sectional study. A validated two-part questionnaire was administered to consenting radiographers at a Nuclear Medicine Department. Part 1 gathered demographic information (age, gender, work experience, attendance to/or passing ionizing radiation protection courses), and part 2 covered questions related to knowledge and level of awareness of radiation protection principles. Results: Five radiographers voluntary participated (2/5 males and 3/5 females). Three age groups were distinguishable, 21-30, 41-50 and 51-60 years. In the age group of 21-30 years, there was one male with just over 4 years of experience while in the age group 41-50, there were three females with less than three years of experience, and in the age group 51-60, there was one male radiographer with over 20 years of experience. All the radiographers showed a high level of awareness and knowledge of radiation safety principles. Conclusion: Education coupled with training in radiation protection is an essential tool for instilling radiation awareness among the radiographers. However, education alone is not enough; further skills in the preparation and administration of radiopharmaceuticals will reduce the exposure.

Purpose: Despite advances in medical technology, radiation-induced dermatitis occurs in 95% of cancer patients receiving radiation therapy. Currently, there is no standard and effective treatment for the prevention or control of radiation dermatitis. The aim of this study was to determine the efficacy of nano-curcumin in alleviating the radiation-induced skin reactions (RISRs) in breast cancer patients. Methods: A randomized, triple-blinded, placebo-controlled clinical trial was performed on 42 patients with breast cancer. The patients were randomly allocated to receive radiotherapy plus placebo (control group) and radiotherapy plus 80 mg/day nano-curcumin capsules (treatment group) up to two weeks after the end of treatment. Then, the RISRs (graded by the radiation therapy oncology group (RTOG) scale) and pain level of the patients were evaluated at baseline and weekly. Finally, the results were analyzed by T-test and Pearson chi-square test. Results: According to the RTOG scale, 0%, 14.28%, and 85.71% of patients in the control group showed grades 0, 1, and 2 RISRs, respectively. In the treatment group, it was observed that 9.52%, 47.61%, and 42.85% of patients had grades 0, 1, and 2 RISRs, respectively. Compared to the control group, it was found that concomitant use of the nano-curcumin supplement did not significantly reduce the RISR severity during the first to sixth weeks (P > 0.05); however, there was a significant difference at week 7 (P = 0.01). Moreover, the patient-reported pain, as the secondary endpoint, was significantly reduced in the treatment group compared with the control group (P < 0.05). Conclusions: In general, it was found that the administration of nano-curcumin could alleviate radiation- induced skin toxicity of breast cancer patients, but this effect was not significant.

Background: The worldwide usage of [¹⁸F]-sodium fluoride in clinical applications has increased the interest in the facility of its production. The development of a new automated method for multi-preparations of [¹⁸F]-NaF and [¹⁸F]FDG on an Explora FDG4 module is described. Explora FDG4 is one of the most widely used synthesizers for FDG production in daily routine use and is specifically designed to run up to four different productions with a single module. Therefore, slight modifications are carried out in order to increase the potential of the synthesizer to perform more radiopharmaceuticals. Methods: A fully automated method for multi-preparations of [¹⁸F]-NaF and [¹⁸F]FDG using Explora FDG4 was developed. Slight modifications to the Explora’s hardware and software configuration were applied. A new elution vial for NaF preparation was installed and connected to the free position to MVP1. Quality control was carried out using the standard analytical methods applied for GMP production. Results: This modification successfully provides preparation of [¹⁸F]-NaF without affecting the daily FDG production using one set preparation. [¹⁸F]-NaF was obtained in a high radiochemical yield (>90%, n=100) in 10 min total preparation time. The quality control results for both obtained products, FDG (RCP >95%) and NaF (RCP >98%), showed that the radiopharmaceuticals were in compliance with USP and Ph.Eur. specifications and compatible with clinical applications. Conclusion: A rapid and simple method for multi preparations of [¹⁸F]-NaF and [¹⁸F]FDG using a single Explora module was designed. Yet, the chemistry module has the potential to generate more radiopharmaceuticals to decrease the cost of preparation of [¹⁸F]-NaF compared to the cassette-based synthesizers, reducing radiation exposure resulting from manual preparations and increasing the reproducibility of [¹⁸F]-NaF preparation.