Tenosynovial giant cell tumor (TSGCT) is a rare neoplasm. Although surgical resection is the widely accepted primary treatment for TSGCT, recurrences are frequent, and patients’ joint function may be severely compromised. Previous studies reported that CSF1‐COL6A3 fusion genes were identified in approximately 30% of TSGCTs. The aim of our study was to comprehensively clarify the genomic abnormalities in TSGCTs. We performed whole exome sequencing in combination with target sequence validation on 34 TSGCT samples. RNA sequencing was also performed on 18 samples. RNA sequencing revealed fusion transcripts involving CSF1, including novel CSF1‐VCAM1, CSF1‐FN1 and CSF1‐CDH1 fusions, in 13/18 (72%) cases. These fusion genes were validated by chromogenic in situ hybridization. All CSF1 fusions resulted in the deletion of CSF1 exon 9, which was previously shown to be an important negative regulator of CSF1 expression. We also found that 12 (35%) of the 34 TSGCT samples harbored CBL missense mutations. All mutations were detected in exons 8 or 9, which encode the linker and RING finger domain. Among these mutations, C404Y, L380P and R420Q were recurrent. CBL‐mutated cases showed higher JAK2 expression than wild‐type CBL cases (p = 0.013). CSF1 fusion genes and CBL mutations were not mutually exclusive, and both alterations were detected in six of the 18 (33%) tumors. The frequent deletion of CSF1 exon 9 in the fusion transcripts suggested the importance of this event in the etiology of TSGCT. Our results may contribute to the development of new targeted therapies using JAK2 inhibitors for CBL‐mutated TSGCT.

Thirty-nine cases of primary intracranial arachnoid cyst in the elderly, including one case of our own, were analyzed. Clinical characteristics in these patients were as follows. (1) The number of patients decreased with age, but there were no differences according to sex. (2) Clinical manifestations were similar to those of chronic subdural haematoma or normal pressure hydrocephalus including dementia, urinary incontinence, and hemiparesis. General symptoms such as headache and seizures were also present. (3) Surgery was performed in most patients with generally good outcome regardless of operative procedures (capsular resection vs. shunt). (4) In some cases of advanced age, disease manifestation may have been due to slight head injuries.

Context Adults with X-linked hypophosphatemia (XLH) present complications other than osteomalacia. Objective To describe the incidence and severity of comorbidities in adults with XLH. Design Observational retrospective study. Patients A total of 25 adults with XLH with thorough investigations, including spinal computed tomography scans, X-rays of hip/knee joints and Achilles tendons, abdominal ultrasounds and audiograms. Main outcome measures The index of ossification of the anterior/posterior longitudinal ligament and yellow ligament (OA/OP/OY index) and the sum of OA/OP/OY index (OS index) were utilized to evaluate the severity of spinal ligament ossification. The Kellgren-Lawrence (KL) classification was adopted to evaluate the severity of the hip/knee osteophytes. Results The participants consisted of 13 male patients and 12 female patients from 21 families, with a median age of 43 (range, 18-72) years. In all, 20 patients (80%) showed spinal ligament ossification. The median OA/OP/OY/OS indices were 2 (0-22), 0 (0-15), 6 (0-13) and 12 (0-41), respectively. Hip/knee osteophytes were reported in 24 (96%) and 17 cases (68%). The median KL grade was 3 in the hip joint and 2 in the knee joint, and 18 cases (72%) developed enthesopathy in the Achilles tendon. Nephrocalcinosis and hearing impairment were observed in 18 (72%) and eight (32%) cases. Conclusion This study revealed a high prevalence and severity of ectopic ossification and disclosed the incidence of nephrocalcinosis and hearing impairment in adults with XLH. In cases with severe spinal ligament ossification or noticeable osteophytes around the hip/knee joints, undiagnosed XLH should be considered as a possible underlying condition.

Background Although initial trabectedin (1.2 mg/m2) is safe and effective for patients with translocation‐related sarcoma (TRS) in Japan, its efficacy in other types of soft‐tissue sarcomas (STSs) remains unknown. This study retrospectively investigated its efficacy and safety through postmarketing surveillance of trabectedin in patients with unresectable and relapsed STS. Methods One hundred forty patients received intravenous trabectedin (1.2 mg/m2 on day 1 every 21 days) over the course of 24 hours. The primary endpoint was the efficacy and safety of trabectedin. Results Grade 3 or higher adverse events occurred in 100 patients (71%) and included hepatotoxicity (37.8%), neutropenia (32.8%), and rhabdomyolysis (3.6%). Patients at high risk for grade 3 or higher rhabdomyolysis (36%) were classified by height (≥170.3 cm) and age (≤32 years) through a classification and regression tree model (area under the curve, 0.9). The overall median progression‐free survival (PFS) was 3.7 months; with respect to the histological type, the median PFS was 17.4 months for myxoid liposarcoma, 4.9 months for leiomyosarcoma, 5.6 months for synovial sarcoma, and 3.7 months for dedifferentiated liposarcoma. Histological type (liposarcoma/leiomyosarcoma [L‐sarcoma] and TRS) and grade 3 neutropenia (but not grade 4) were associated with significantly improved PFS after trabectedin treatment (P = .003, P = .04, and P = .001). The median growth modulation index (GMI) was 0.91; 37 patients (36.7%) experienced a GMI > 1.33, and among patients with solitary fibrous tumors and undifferentiated pleomorphic sarcoma, 60% and 42.9%, respectively, had a GMI > 1.33. The median overall survival (OS) was 16.4 months. A GMI > 1.33 was associated with significantly improved OS (P = .0006). Conclusions Initial trabectedin at 1.2 mg/m2 has clinically meaningful benefits for patients with L‐sarcoma and certain histological subtypes of TRS.

Negative surgical margin was associated with better survival. Coexisting conditions had an impact on outcomes in elderly soft-tissue sarcoma patients.