Dual-Time-Point 18F-Fluorocholine PET/CT Improves Characterization of Thyroid Nodules in Patients Referred for Primary Hyperparathyroidism: A Proof of Concept Study.

PURPOSE: Thyroid nodules frequently coexist with primary hyperparathyroidism (pHPT). Because of the increasing use of 18F-fluorocholine (18F-FCH) PET/CT in patients with pHPT, evaluation of its clinical utility for thyroid nodules characterization in this population is of paramount importance. Herein, we investigate the value of dual-point 18F-FCH PET/CT in the diagnosis of thyroid cancer in patients referred for pHPT imaging who have thyroid nodules. PATIENTS AND METHODS: All pHPT patients who underwent a dual-time point 18F-FCH PET/CT (at 5 and 60 minutes postinjection) between July 2019 and December 2020 were analyzed. Only those with a thyroid nodule greater than 10-mm and pathological analysis (criterion standard) were included. Nodule-to-thyroid SUVmax ratio was calculated at the 2 study points, as well as the 18F-FCH washout index (WO%). RESULTS: Twenty-seven patients (32 nodules) were included in this study. The final diagnoses were as follows: 27 benign nodules including 2 NIFTPs (noninvasive follicular thyroid neoplasm with papillary-like nuclear features) and 5 cancers of follicular origin. Early uptake ratio was significantly higher in malignant lesions than in benign nodules (P = 0.0008). Thyroid cancers were also characterized by a marked 18F-FCH washout index (WO% benign vs cancer: 2.9% ± 4.1% vs 45.5% ± 13.4%, P = 0.0001). Using a WO% threshold of 22.1%, 25/27 benign nodules and 5/5 malignant lesions were accurately classified (sensitivity of 100%, specificity of 92.6%, positive predictive value of 71.4%, and negative predictive value of 100%). The false-positive findings were related to the 2 NIFTPs that share similarities with thyroid cancer. CONCLUSIONS: Our preliminary results suggest to perform a dual-time-point PET/CT acquisition protocol in pHPT patients with uncharacterized centimeter thyroid nodules. However, the real impact of these promising results should be assessed by prospective studies on a larger cohort of patients.

Bone metastases from a 1p/19q codeleted and IDH1-mutant anaplastic oligodendroglioma: a case report.

BACKGROUND: Oligodendroglioma is a rare type of primary brain tumor which, like other malignant gliomas, metastasizes very rarely even when in high-grade form. CASE REPORT: A 36-year-old white man diagnosed 29 months previously as having 1p/19q codeleted anaplastic oligodendroglioma presented bilateral cruralgia and lower limb motor deficits. A computed tomography scan showed multiple osteoblastic bone lesions. The presence of oligodendroglial cells was revealed by bone marrow biopsy and confirmed by immunohistochemical analyses. A positon emission tomography-computed tomography scan confirmed the exclusive involvement of bones. CONCLUSION: This case joins less than 20 other reported cases of oligodendroglioma bone marrow metastasis, and is one of only a handful of cases of diffuse bone metastases beyond the axial skeleton. To the best of our knowledge, the early relapse of 1p/19q codeleted anaplastic oligodendroglioma with this distribution of metastases has never been described in the literature.

Contribution of three-dimensional conformal intensity-modulated radiation therapy for women affected by bulky stage II supradiaphragmatic Hodgkin disease.

PURPOSE: To analyze the outcome and dose distribution of intensity-modulated radiation therapy (IMRT) by helical tomotherapy in women treated for large supradiaphragmatic Hodgkin's disease. MATERIAL AND METHODS: A total of 13 patients received adjuvant radiation at a dose of 30 Gy to the initially involved sites with a boost of 6 Gy to those areas suspected of harboring residual disease on the simulation CT scan. RESULTS: With a median follow-up of 23 months, the two-year progression-free survival was 91.6%, and the 2- and 3-year overall survivals were 100%. We did not report any heart or lung acute side effects. The conformity index of PTV (Planning Target Volume) was better for IMRT than for 3D-CRT (p=0.001). For the breasts, lungs, heart, thyroid and esophagus, the volume distributions favored the IMRT plans. For the breasts, the V(20Gy), V(25Gy) and V(30Gy) were 1.5, 2.5 and 3.5 times lower, respectively, for IMRT than for 3D-CRT. For the lung tissues, the V(20Gy) and V(30Gy) were 2 times and 4.5 times lower, respectively, for IMRT than for 3D-CRT. For the heart, the V(20Gy) and V(30Gy) were 1.4 and 2 times lower, respectively, for IMRT than for 3D-CRT. For the esophagus, the V(35Gy) was 1.7 lower for IMRT than for 3D-CRT, and for the thyroid, the V(30Gy) was 1.2 times lower for IMRT. CONCLUSION: IMRT by helical tomotherapy improved the PTV coverage and dramatically decreased the dose in organs at risk. The treatment was well tolerated, but a longer follow-up is necessary to prove a translation of these dosimetric improvements in the outcome of the patients.

High-frequency ultrasound detection and follow-up of Wilms' tumor in the mouse.

The goal of this study was to validate high-frequency (24 MHz) ultrasound imaging techniques for early detection and follow-up of renal tumors in a murine Wilms' tumor model (n = 26). For 11 mice, maximum tumor dimensions were estimated from images along three orthogonal axes for comparison with posteuthanasia caliper and histologic measurements. Tumor size in the 15 remaining mice was checked biweekly. The mice were then euthanized and histologic study assessed tumor position and nature. Tumors were detected in vivo between 7 to 14 days after injection of tumor-inducing cells. Tumor maximum cross-sectional area varied from 0.07 mm2 to 5.7 mm2 at the time of initial detection. The relative r.m.s. error between ultrasonic and histologic estimations of maximum cross-sectional area was estimated to be 19%. Results demonstrate feasibility of noninvasive ultrasound biomicroscopy early detection and characterization of renal tumor development for longitudinal monitoring of the same animal.