Objective: In the differential diagnosis between uterine fibroids and uterine sarcomas, realworld magnetic resonance imaging (MRI) diagnostic information is scarce; furthermore, high diagnostic sensitivity is important in clinical practice. We previously developed a diagnostic algorithm to detect uterine sarcoma with high sensitivity using simple MRI images and serum lactate dehydrogenase (LDH) levels. In this multicenter study, we investigated the preoperative diagnosis of sarcoma in the real world and further validated the usefulness of our diagnostic algorithm. Methods: Of 154 uterine sarcomas and 154 uterine fibroids treated at 15 centers between January 2006 and December 2020, 139 sarcomas (16 smooth muscle tumors of uncertain malignant potential) and 141 fibroids with diffusion-weighted imaging information were included in the analysis. The diagnostic algorithm was validated by 3 radiologists who were blinded to the clinical information and pathologic diagnoses and who read the MRIs. Results: The sensitivity/specificity of preoperative diagnosis was 77.7%/92.9% for the preoperative report; 92.1%/72.3% for algorithm A; and 82.0%/85.8% for algorithm B (McNemar’s test p<0.05). Comparison of overall survival rates among 3 groups (Group 1: negative A, Group 2: positive A and negative B; Group 3: positive B) using algorithms A and B showed p=0.012. On multivariate analysis, stage, and serum LDH level were independent prognostic factors. Conclusion MRI is useful for preoperative diagnosis of uterine sarcoma, and the sarcoma diagnostic algorithm presented in this study is an option for diagnosing sarcoma with greater sensitivity. This information should be shared with patients.

Objective: DNA methyltransferase 1 (DNMT1) is crucial to maintaining methylation during DNA replication and DNA repair. DNMT1 mutations have been identified in two neurological syndromes, including hereditary sensory and autonomic neuropathy type IE (HSAN IE) with dementia and hearing loss and autosomal dominant cerebellar ataxia, deafness and narcolepsy. It is likely that DNMT1 mutations lead to various symptoms of the central and peripheral nervous system. The aim of this study was to examine the clinical characteristics, especially the initial symptoms, in the cases of DNMT1 mutations. Methods: We investigated the clinical manifestation and examination findings of four cases of HSAN IE from one family with the DNMT1 mutation c.1531Y>C (p.Try511His). Results: All four cases exhibited sensory neuropathy, cerebellar ataxia, and hearing loss, all of which were demonstrated by the audiograms. The initial symptoms of the four cases included hearing loss (n=1), gait disturbance (n=1), and depressive mood (n=2). Depressive symptoms are reported in some cases with HSAN IE, however, there are currently no published reports that describe them as primary symptoms. The CSF orexin level was measured in three cases, revealing normal values in two cases and intermediate values in one case, in which the patient exhibited rapid eye movement (REM) sleep behavior disorder. Conclusion: Our findings suggest that in cases with HSAN IE or the DNMT1 mutation, psychiatric symptoms should be taken into account as one of the initial manifestations of the disease.