Pretreatment 18F-FDG PET/CT combined with quantification of clonal circulating plasma cells as a potential risk model in patients with newly diagnosed multiple myeloma.

PURPOSE: Both 18F-FDG PET/CT and clonal circulating plasma cell (CPC) quantification are emerging tools for multiple myeloma (MM) prognostication that have been validated in recent studies. This study investigated the value of PET/CT coupled with CPC quantification for MM prognostication that may contribute to future risk-adapted treatment. METHODS: We retrospectively analysed the prognostic relevance of a combination of pretreatment PET/CT findings and CPC levels in 163 consecutive patients with newly diagnosed, symptomatic MM receiving novel agents during induction therapies. RESULTS: High-risk PET/CT findings and elevated CPC levels were defined by the presence of >3 focal lesions with or without extramedullary disease and CPCs ≥0.10% of the total mononuclear cells evaluated, respectively. Subsequently, patients were divided into three groups: PET-CPC stage I included patients with no high-risk PET/CT findings and low CPC levels; stage III included patients with high-risk PET/CT findings and high CPC levels; and stage II included the remaining patients. The three groups of patients differed significantly in terms of both progression-free survival (PFS) and overall survival (OS) (median PFS: not reached [NR] and 36.4 and 15.9 months, and median OS: NR, NR, and 40.4 months for stages I, II, and III, respectively; P < 0.001 for both PFS and OS). This system discriminated both PFS and OS even among younger (age < 75 years) or older (≥ 75 years) patients, patients with Revised International Staging System stage II or III, and patients with or without high-risk cytogenetic characteristics. In the multivariate analysis, the PET-CPC staging system remained prognostic for both PFS and OS. CONCLUSIONS: The PET-CPC staging system predicted survival outcomes independently of established risk factors in patients with newly diagnosed MM. Pretreatment 18F-FDG PET/CT assessment combined with CPC quantification may improve the prognostication of MM and facilitate the development of novel risk-adapted approaches for MM.

Low hexokinase-2 expression-associated false-negative 18F-FDG PET/CT as a potential prognostic predictor in patients with multiple myeloma.

PURPOSE: False-negative 18F-FDG PET/CT, which is associated with low hexokinase-2 (HK2) expression in multiple myeloma (MM), is a new concept that is relevant for diagnosis and treatment response assessment. This study aimed to investigate the prognostic relevance of low HK2 expression-associated false-negative PET/CT in patients with MM. METHODS: Ninety consecutive patients, with newly diagnosed MM, receiving novel agents during induction therapy were enrolled in this retrospective study. Patients were divided into three groups according to the combination of the positivity of PET/CT and whole-body diffusion-weighted magnetic resonance imaging (DWMRI), namely, negative DWMRI, false-negative PET/CT, and positive PET/CT. RESULTS: False-negative PET/CT was observed in 12% patients who were older, had documented clinical history of smouldering MM, and showed lower HK2 expression levels than the positive PET/CT patients. False-negative PET/CT patients showed a clear trend of longer time to next treatment (TTNT) and progression-free survival (PFS) than the positive PET/CT patients (P = 0.035 and 0.071, respectively). Furthermore, TTNT and PFS of false-negative PET/CT patients were similar to those of patients without established high-risk PET/CT findings and significantly longer than those of high-risk PET/CT patients (P = 0.013 and 0.047, respectively). CONCLUSIONS: This study showed, for the first time, that low HK2 expression-associated false-negative PET/CT was associated with relatively better prognosis in patients with newly diagnosed MM, suggesting that this phenomenon may not undermine the established PET/CT-based prognostication. Furthermore, this phenomenon may be useful for identifying patients at lower risk of disease progression among those with myelomatous lesions on DWMRI.

Persistent primitive trigeminal arteries (PTA) and its variant (PTAV): analysis of 103 cases detected in 16,415 cases of MRA over 3 years.

INTRODUCTION: The primitive persistent trigeminal artery (PTA) is the most common carotid-basilar anastomosis, but because of its extremely low incidence, it is poorly understood. The purpose of this study is to clarify the features of PTA and its variants (PTAV) based on a large magnetic resonance angiography (MRA) series. METHODS: MRA was performed on continuous 16,415 patients (8,610 males and 7,805 females) between October 2005 and September 2008 using two 1.5-T systems and one 1.0-T system. These all MRAs were evaluated by neuroradiologists. RESULTS: The incidence of both PTA and PTAV was 0.68% (48 cases of PTA, 50 cases of PTAV, and five unclassified). Among them, 65 cases originated from the left internal carotid artery and 38 from the right. There were 44 cases of lateral type PTA and four cases of medial type. Hypoplasia of the basilar artery proximal to the union of PTA was recognized as follows: no hypoplasia in 12 cases, moderate hypoplasia in 22 cases, and severe hypoplasia in 13 cases. Distance from SCA and the union was an average of 6.7 mm. Four cases of pre- and postoperative cerebral aneurysms were recognized in 103 cases (3.9%). CONCLUSION: We have identified details of both PTA/PTAV. The incidence of PTA was similar to previous studies, and the co-existence of cerebral aneurysm was also similar when compared to patients in the general population without PTA or PTAV.

Imaging characteristics of the postoperative globe: a pictorial essay.

Recognizing imaging characteristics after ophthalmic surgery is necessary for radiologists to prevent misdiagnosis. We review typical appearances of intraorbital implanted devices and materials on CT and MRI with demonstration of the common surgical procedures. EX-PRESS glaucoma filtration devices appear as punctate areas of metal attenuation on CT and are typically placed at the corneoscleral junction. The imaging manifestations after cataract extraction are absence of the native lens of ovoid mass and the intraocular lens with high attenuation on CT and low signal intensity on MRI. The treatment of retinal detachment is achieved with intraocular tamponade or scleral buckling. In intraocular tamponade, the eye is filled with a bubble of gas or silicone oil. Gas results in air attenuation on CT and low signal intensity on MRI in the vitreous cavity. Silicone oil is hyperattenuating on CT and has variable intensity on MRI. In scleral buckling, the eye wall is indented with silicone buckling elements that show high or low attenuation on CT and low T1- and T2-weighted intensity on MRI. Degraded hydrogel buckling elements appear as swollen masses showing low attenuation on CT and high T2-weighted intensity on MRI.