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Simultaneous imaging of the SPECT tracer 131 I and PET tracer 18 F is important in the diagnosis of high- and low-grade thyroid cancers because high-grade thyroid cancers have high 18 F-FDG and low 131 I uptake, while low-grade thyroid cancers have high 131 I and low 18 F-FDG uptake. In this study, Na 131 I and 18 F-FDG were simultaneously imaged using the Compton-PET system, in vivo. The angular resolution and sensitivity of the Compton camera with 356 keV gamma ray measured using a 133 Ba point source were 12.3° and 2 × 10 -5 , respectively. The spatial resolution and sensitivity of PET were measured with a 22 Na point source. The transaxial and axial spatial resolutions of the PET at the center of the FOV were 1.15 mm and 2.04 mm, respectively. Its sensitivity was 1.2 × 10 -4 . In-vivo images of the 18 F and 131 I isotopes were simultaneously acquired from mice. These showed that 18 F-FDG was active in the heart, brown fat, and brain, while Na 131 I was active in the thyroid, stomach, and bladder. Artifacts were found in the Compton camera images when the activity of 131 I was much lower than that of 18 F. This study demonstrates the potential of simultaneous clinical imaging of 18 F and 131 I., (© 2024. The Author(s).)

The anti-programmed cell death-1 (PD-1) antibody nivolumab has been shown to significantly prolong the survival of patients with unresectable advanced or recurrent gastric cancer (AGC). However, immune-related adverse events (irAEs), which show different profiles from those of cytotoxic agents or conventional molecular-targeted drugs including tyrosine kinase inhibitors, have been reported. Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) is a rare autoimmune disorder with acute-onset, rheumatoid factor-negative, symmetric synovitis associated with limb edema observed in elderly persons. A case of RS3PE syndrome that developed after administration of nivolumab for advanced gastric cancer is reported. This is the first report of a case of RS3PE syndrome as an irAE caused by nivolumab in a patient with gastric cancer., Competing Interests: HA: Speakers’ bureau from Ono Pharmaceutical and Bristol-Myers Squibb, KT: Speakers’ bureau from Ono Pharmaceutical, MA: Speakers’ bureau from Bristol-Myers Squibb, HN: Honoraria from Ono Pharmaceutical and Bristol-Myers Squibb and Speakers’ bureau from Ono Pharmaceutical and Bristol-Myers Squibb, KA: Lecture fees from Ono Pharmaceutical and Bristol-Myers Squibb, EB: Honoraria from Ono Pharmaceutical and Bristol-Myers Squibb. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ohmura, Kondo, Uenomachi, Ariyama, Ito, Tsuchihashi, Ayano, Niiro, Akashi and Baba.)

In internal 131I therapy for thyroid cancer, a decision to continue treatment is made by comparing 131I scintigraphy and [18F]FDG-PET. However, with current SPECT and PET systems, simultaneous imaging of diagnostic PET nuclides and therapeutic 131I nuclides has not been achieved so far. Therefore, we demonstrated that the recently developed Compton PET hybrid camera with Ce:Gd3(Al,Ga)5O12 (GAGG)- Silicon Photomultiplier(SiPM) scintillation detectors can be used to simultaneously image 131I Compton image and 18F PET image., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Severe pneumonitis induced by nivolumab, an anti-programmed cell death-1 monoclonal antibody, is a rare but potentially fatal immune-related adverse event. In cases of steroid-refractory pneumonitis, an appropriate therapeutic strategy using anti-tumor necrosis factor-α (TNF-α) antibody has not been established. A 59-year-old female was diagnosed with hypopharyngeal squamous cell carcinoma. Previous therapies including chemoradiotherapy and throat laryngectomy were performed, but metastatic recurrence appeared in the intrapulmonary and mediastinal lymph nodes. The patient was administered nivolumab. On the 14th day of nivolumab administration, the patient experienced dyspnea and computed tomography of the chest showed multiple consolidations in the right lung. She was diagnosed with nivolumab-induced pneumonitis. Because the pneumonitis was refractory to steroid therapy, she was administered infliximab, and the pneumonitis improved. On the 72nd and 101st days of nivolumab administration, nivolumab-induced pneumonitis re-appeared with an elevated serum TNF-α concentration. In each occurrence of pneumonitis, repetitive administration of infliximab improved the pneumonitis. Repetitive administration of infliximab may be effective for treating recurrent nivolumab-induced pneumonitis that is associated with an increased serum TNF-α concentration., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Ueno et al.)

Positron-emission tomography (PET) and single-photon-emission computed tomography (SPECT) are well-established nuclear-medicine imaging methods used in modern medical diagnoses. Combining PET with 18 F-fluorodeoxyglucose (FDG) and SPECT with an 111 In-labelled ligand provides clinicians with information about the aggressiveness and specific types of tumors. However, it is difficult to integrate a SPECT system with a PET system because SPECT requires a collimator. Herein, we describe a novel method that provides simultaneous imaging with PET and SPECT nuclides by combining PET imaging and Compton imaging. The latter is an imaging method that utilizes Compton scattering to visualize gamma rays over a wide range of energies without requiring a collimator. Using Compton imaging with SPECT nuclides, instead of the conventional SPECT imaging method, enables PET imaging and Compton imaging to be performed with one system. In this research, we have demonstrated simultaneous in vivo imaging of a tumor-bearing mouse injected with 18 F-FDG and an 111 In-antibody by using a prototype Compton-PET hybrid camera. We have succeeded in visualizing accumulations of 18 F-FDG and 111 In-antibody by performing PET imaging and Compton imaging simultaneously. As simultaneous imaging utilizes the same coordinate axes, it is expected to improve the accuracy of diagnoses., (© 2021. The Author(s).)

Multi-tracer imaging can provide useful information in the definitive diagnosis and research of medical, biological, and pharmaceutical sciences. Single-photon emission computed tomography (SPECT) is one of the nuclear medicine imaging modalities widely used for diagnosis or medical research and has a multi-tracer imaging capability. One of the drawbacks of multi-tracer imaging is crosstalk from other gamma rays, which affects the reconstructed image. Scattering correction methods, such as the dual- and triple-energy window methods, are used for conventional SPECT imaging to reduce the background caused by the crosstalk. This study proposes another crosstalk reduction method. Some nuclides emit two or more gamma rays through intermediate levels. Thus, detecting these gamma rays with the coincidence method allows us to distinguish a true gamma ray signal and a background signal. The nuclide position can be estimated at the intersection of two gamma rays using collimators. We demonstrate herein simultaneous 111 In and 177 Lu imaging via the double-photon coincidence method using GAGG detectors and parallel hole collimators. The double-photon coincidence method greatly reduces the background caused by other gamma rays and offers higher-quality images than does conventional imaging.

Background: Dose modification of chemotherapy for metastatic colorectal cancer (MCRC) is often needed, especially in second-line and later-line treatments due to adverse events of previous treatment and poor patient condition. No study has focused on ramucirumab plus modified dose of FOLFIRI for MCRC, and whether low relative dose intensity (RDI) affects treatment efficacy has not been clarified., Methods: MCRC patients who received ramucirumab plus FOLFIRI, which consisted of 150 mg/m 2 of irinotecan, at six institutions were retrospectively analyzed., Results: A total of 43 patients were assessed. Median age was 63 years, and 22 patients (51%) were women. Twenty-six patients (60%) were given ramucirumab plus FOLFIRI as second-line therapy, and 17 (40%) as third or later-line. The median relative dose intensity (RDI) of irinotecan was 60.6%, which is lower than that in the pivotal phase 3 study (RAISE), and other agents showed the same trend. Median progression-free survival was 4.8 [95% confidence interval (CI) 3.2-5.7] months for all patients, 5.4 (95% CI 3.5-7.2) months for second-line patients, and 2.8 (95% CI 1.6-5.8) months for third or later-line patients. Median overall survival was 17.3 (95% CI 11.5-22.4) months for all patients. Patients with irinotecan RDI less than 60% showed similar treatment efficacy. Hematological toxicities of grade 3 or worse were observed in 21 patients, but all were manageable., Conclusion: Low RDI did not compromise the treatment efficacy of ramucirumab plus modified FOLFIRI for MCRC patients.

Purpose: Standard therapy for advanced small bowel adenocarcinoma (SBA) has not yet been established. The present study assessed the efficacy and safety of chemotherapy (CT) in association with molecular targeting approaches for SBA., Methods: The histories of 33 advanced SBA patients from six different institutions in Japan, who received CT from 2008 to 2016, were retrospectively examined for background, clinical course and outcome., Results: Median patient age was 65 years (range 39-83). Primary tumor was located in the duodenum in 21 patients (67%), the ampulla of Vater in three patients (9%), the jejunum in seven patients (21%) and the ileum in one patient (3%). Histologically, well-to-moderately and poorly differentiated adenocarcinoma were identified in 20 (61%) and nine (27%) patients, respectively. Thirteen patients received a single CT regimen, seven patients received two types of CT regimen, and 13 patients received three or more CT regimens. As first-line CT, modified FOLFOX6, capecitabine plus oxaliplatin, and S-1 plus cisplatin were employed in 13, 1, and 4 patients, respectively. The response rate (RR) and median progression-free survival (PFS) were 25% and 6.0 months, respectively. Median overall survival (OS) was 13.0 months. Nine out of the 33 patients received bevacizumab-containing CT and three received cetuximab-containing CT. Median OS of bevacizumab-containing CT patients was 21.9 months. No unexpected serious adverse events were observed., Conclusions: The analysis indicates that combination CT for advanced SBA is associated with modest efficacy and safety, and bevacizumab-containing CT may contribute to favorable outcome in these patients.