Perivascular epithelioid cell tumors (PEComas) of the bone and soft tissue: a Japanese Musculoskeletal Oncology Group (JMOG) multi-institutional study.

PURPOSE: Perivascular epithelioid cell tumors (PEComas) of the bone and soft tissues are rare mesenchymal neoplasms, some of which are malignant. However, their clinical and pathological characteristics remain unclear. This study was performed to investigate the clinical and pathological characteristics of PEComas in bone and soft tissues by leveraging information from the Japanese Musculoskeletal Oncology Group. METHODS: Nine patients, including four male and five female patients with a median age of 50 years, were retrospectively reviewed. PEComas of the visceral organs, including the uterus and retroperitoneum, were excluded. RESULTS: Eight tumors arose in the soft tissue and one in the bone, with a mean size of 8.8 cm. Four patients showed local recurrence or distant metastasis. The 1-year survival rate was 78%. Pathologically, eight tumors were classified as malignant and one as having uncertain malignancy potential. Half of the tumors showed high MIB-1 index values of > 30%. Immunohistochemically, the melanocyte marker HMB45 was expressed in 89% of the cases, and muscle-specific markers were expressed only in 30-50% of the cases. Transcription factor binding to IGHM enhancer 3 (TFE3) expression was positive in 100% of the patients. Tumors with high expression of TFE3 were classified as PEComas with malignant potential according to Folpe's classification. CONCLUSIONS: Bone and soft tissue PEComas may have a higher malignancy potential than other visceral PEComas and are more likely to develop as TFE3-rearranged PEComas.

Femoral osteomyelitis caused by oral anaerobic bacteria with mixed bacteremia of Campylobacter rectus and Parvimonas micra in a chronic periodontitis patient: a case report.

BACKGROUND: Campylobacter rectus is a gram-negative rod, and Parvimonas micra is a gram-positive coccus, both of which are oral anaerobes that cause chronic periodontitis. Chronic periodontitis can cause bacteremia and systemic diseases, including osteomyelitis. Hematogenous osteomyelitis caused by anaerobic bacteria is uncommon, and to date, there have been no reports of mixed bacteremia with C. rectus and P. micra. Here, we report the first case of osteomyelitis of the femur caused by anaerobic bacteria with mixed bacteremia of C. rectus and P. micra caused by chronic periodontitis. CASE PRESENTATION: A 75-year-old man with chronic periodontitis, hyperuricemia, and benign prostatic hyperplasia was admitted to the hospital with a fracture of the left femur. The patient had left thigh pain for 4 weeks prior to admission. Left femoral intramedullary nail fixation was performed, and a large amount of abscess and necrotic tissue was found intraoperatively. The cultures of abscess specimens were identified as P. micra, Fusobacterium nucleatum, and C. rectus. C. rectus and P. micra were also isolated from blood cultures. C. rectus was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16 S ribosomal RNA sequencing. Sulbactam-ampicillin was administered for approximately 1 month, after which it was replaced by oral clavulanic acid-amoxicillin for long-term suppressive treatment. CONCLUSIONS: Only five cases of bloodstream infection with C. rectus have been reported, and this is the first report of mixed bacteremia with P. micra. Clinicians should consider that chronic periodontitis caused by rare oral anaerobic bacteria can cause systemic infections, such as osteomyelitis.

Efficacy of auranofin as an inhibitor of desmoid progression.

Anticancer drugs and molecular targeted therapies are used for refractory desmoid-type fibromatosis (DF), but occasionally cause severe side effects. The purpose of this study was to identify an effective drug with fewer side effects against DF by drug repositioning, and evaluate its efficacy. FDA-approved drugs that inhibit the proliferation of DF cells harboring S45F mutations of CTNNB1 were screened. An identified drug was subjected to the investigation of apoptotic effects on DF cells with analysis of Caspase 3/7 activity. Expression of ß-catenin was evaluated with western blot analysis, and immunofluorescence staining. Effects of the identified drug on in vivo DF were analyzed using Apc1638N mice. Auranofin was identified as a drug that effectively inhibits the proliferation of DF cells. Auranofin did not affect Caspase 3/7 activity compared to control. The expression level of ß-catenin protein was not changed regardless of auranofin concentration. Auranofin effectively inhibited the development of tumorous tissues by both oral and intraperitoneal administration, particularly in male mice. Auranofin, an anti-rheumatic drug, was identified to have repositioning effects on DF. Since auranofin has been used for many years as an FDA-approved drug, it could be a promising drug with fewer side effects for DF.

Factors Affecting Delay in Initial Treatment of Patients with Soft Tissue Sarcomas.

Background: Soft tissue sarcomas (STS) are rare, and little is known about the factors that affect the delays in the initial treatment. The aim of this study is to quantify the period between onset of symptoms and start of treatment of STS and determine the factors affecting delays in initial treatment. Methods: This is a retrospective study of all STS treated in our institution between October 2009 and March 2019. We analysed patient record to determine the period from onset of symptoms to start of initial treatment. We also collected data with regard to patient characteristics and features of the tumour. Tumours were classified into upper extremity, lower extremity, trunk and others based on location of the tumour. Statistical tests were done to identify factors that affected delay in initial treatment. Results: The study included 134 patients (76 male and 58 female) with STS with an average age of 56.6 years. The tumours involved the upper extremity in 20 patients, lower extremity and trunk in 50 patients each and other areas in 14 patients. The most frequent histological subtypes were liposarcomas (n = 31, 23.5%) and undifferentiated pleomorphic sarcomas (n = 24, 18.2%). Initial treatment was delayed by an average of 9.9 months for all groups. The period of treatment delay for tumours involving the upper extremity was shorter (7.9 months) and these tumours were smaller at initial presentation (57.6 mm) compared to tumours in other locations (p < 0.05). Other factors that were positively associated with treatment delays were a history of diabetes mellitus (p = 0.037) and smoking (p = 0.026). Conclusion: Patients with upper-extremity STS may have the benefit of a relatively better prognosis as they present earlier and with a smaller tumour. In addition, factors, such as diabetes and smoking, which indicate a low interest in health also influenced the delay in the initial treatment. Level of Evidence: Level III (Therapeutic).

Recurrent giant cell tumour of the distal ulna after en bloc resection with preoperative denosumab use.

In recent years, denosumab has been used to treat giant cell tumour of bone (GCTB) not only in cases where surgery is complicated but also preoperatively to decrease the preoperative grade or to facilitate surgery for Campanacci grade II and III cases. However, there are no clear protocols regarding the preoperative use of denosumab before en bloc resection. There are a few reports of recurrent cases after en bloc resection; however, the association with the use of denosumab is unknown. We present the clinical, radiological and histopathological findings of a case of Campanacci grade III GCTB at the distal end of the ulna, which resulted in soft tissue recurrence after en bloc resection with the preoperative use of denosumab.

Trends in diagnostic and therapeutic strategies for extra-abdominal desmoid-type fibromatosis: Japanese musculoskeletal oncology group questionnaire survey.

OBJECTIVE: The mainstay of treatment modality for extra-abdominal desmoid-type fibromatosis (DF) has shifted from surgery, which often impairs ADL/QOL, to conservative treatment including active surveillance. In the present study, we conducted a longitudinal survey on the diagnosis and treatment of DF at facilities belonging to the Japanese Musculoskeletal Oncology Group, which is a research group of facilities specializing in the treatment of bone and soft tissue tumors in Japan to clarify the transition of medical care for extra-abdominal DF. METHODS: The same questionnaire was administered in 2015 and 2018, and responses were obtained from 46 (69%) of 67 facilities and 42 (53%) of 80 facilities in 2015 and 2018, respectively. RESULTS: Although immunostaining for ß-catenin was often used for the pathological diagnosis in both 2015 and 2018, CTNNB1 mutation analysis was not performed either in 2015 or in 2018. As for the treatment strategy for resectable cases, surgical treatment including wide resection was selected at 11 facilities (24% of respondents) in 2015, and further decreased to 5 facilities (12%) in 2018. Conservative treatment with active surveillance or medical treatment was the most common treatment for both resectable and difficult-to-resect cases. COX-2 inhibitors and tranilast were often used in the drug treatment of both resectable and difficult-to-resect cases. Few facilities provided radiotherapy, methotrexate and vinblastine, or DOX-based chemotherapy for refractory cases in both 2015 and 2018. CONCLUSIONS: A good trend was found in the questionnaire survey. It will be further necessary to disseminate clinical practice guidelines to physicians more widely, and to have them understand and implement the most up-to-date medical practice strategies for this rare disease.

Less-invasive fascia-preserving surgery for abdominal wall desmoid.

The mainstay of treatment for desmoid has been shifted to active surveillance (AS). However, surgery is still being performed on abdominal wall desmoid with a wide surgical margin. The purposes of this study are to clarify the treatment results of less-invasive, fascia preserving surgery for patients with abdominal wall desmoid, and to propose a new treatment modality. Since 2009, 34 patients with abdominal desmoid have been treated in our institution. Among them, as a final treatment modality, 15 (44%) were successful with AS, 15 were subjected to less-invasive surgery, and 4 methotrexate and vinblastine treatment. The clinical results of less-invasive surgery were clarified. In the surgical group, although the surgical margin was all microscopic positive (R1), only one patient (6.7%), who has the S45F mutation type of CTNNB1, showed recurrence, at a mean follow-up of 45 months. There were no patients with familial adenomatous polyposis (FAP)-related desmoid in this cohort. Only two patients (13%) required fascia lata patch reconstruction after removal of the tumor. In patients with non FAP-related abdominal wall desmoid, less-invasive, fascia preserving surgery is recommended as a favorable option as active treatment. Based on the results of this study, multi-institutional further research is warranted with an increased number of patients.

Current practice patterns of osteoporosis treatment in cancer patients and effects of therapeutic interventions in a tertiary center.

Cancer and osteoporosis have high incidence rates in older populations. However, the treatment of osteoporosis among cancer patients has not been adequately described. Our purpose was to clarify the current practice patterns of osteoporosis treatment among cancer patients in an academic cancer center, and to analyze the efficacy of treatment interventions. Patient records from April 2009 to March 2018 were retrospectively reviewed, and the study included a total of 316 cancer patients with osteoporosis. After patients' data extraction, the patients were divided into two groups, with (n = 144) or without treatment (n = 172), and compared the outcomes of these groups to evaluate the medication effect. The primary outcome was new radiographic fragility fractures during the study period. The related factors associated with fracture injuries and the rate of adverse events, such as osteonecrosis in the jaw and atypical femoral fractures, were analyzed. The rate of treatment intervention was 45.6% among the patient groups. Among patients in the study group, breast cancer patients (n = 107) were mostly treated (n = 79, 73.8%) with oral bisphosphonate. A significant difference in new fracture rate was observed between the two groups (treatment group, 30.6%; non-treatment group, 54.7%), and the risk of fracture was 42% lower in the treatment group (hazard ratio, 0.58; 95% confidence interval, 0.39-0.86; p<0.05). Previous chemotherapy, steroid use, and older age were significantly associated with increased rate of new fragility fractures. The adverse event rate was 3.5% (presented in five cases). Older cancer patients who receive chemotherapy or steroids are strongly recommended undergo bone quality assessment and appropriate osteoporosis treatment to improve their prognosis.

Phase II clinical trial of pazopanib for patients with unresectable or metastatic malignant peripheral nerve sheath tumors.

Malignant peripheral nerve sheath tumor (MPNST) often does not respond well to chemotherapy and develops against a background of NF1. The purpose of our study was to examine the efficacy of pazopanib against MPNST. Our study was designed as a physician-initiated phase II clinical trial in patients with advanced MPNST. Patients were registered from 11 large hospitals. The primary endpoint was set to clarify the clinical benefit rate (CBR) at 12 weeks according to response evaluation criteria in solid tumors (RECIST). Progression-free survival (PFS), overall survival (OS) and the CBR based on modified Choi evaluation at week 12 were set as secondary endpoints along with treatment-related safety. The study enrolled 12 patients. Median age was 49 years. Seven had Grade 2 and five Grade 3 according to the FNCLCC evaluation. Median follow-up period was 10.6 months. CBR at 12 weeks was both 50.0% (RECIST and Choi). The median PFS was 5.4 months for both RECIST and Choi, and the median OS was 10.6 months. Of special interest, the median PFS was 2.9 months for patients with FNCLCC Grade 2 and 10.2 months for Grade 3 (both RECIST and Choi). Grade 4 adverse events of neutropenia and lipase elevation were noted in one patient each. The results of this pazopanib therapy were generally better than those of any of the other single molecular targeted therapies reported previously. Although accumulation of more cases remains necessary, we conclude pazopanib treatment for MPNST to be a safe and promising treatment after doxorubicin-based chemotherapy.

Desmoid with biweekly methotrexate and vinblastine shows similar effects to weekly administration: A phase II clinical trial.

Low-dose methotrexate (MTX) plus vinblastine (VBL) chemotherapy is an effective treatment for desmoid-type fibromatosis (DF). However, previous reports have described a weekly regimen, with no reports available on a biweekly one. The aim of this study was to determine the clinical outcomes of a biweekly regimen in a cohort prospectively treated in our single institution. Since 2010, we have prospectively treated refractory DF patients with biweekly MTX (30 mg/m2 ) + VBL (6 mg/m2 ). Efficacy, progression-free survival (PFS), and correlating factors were analyzed. Adverse events (AEs) were recorded. In total, 38 patients received low-dose MTX + VBL therapy, and its efficacy was assessed in 37 of them. Nineteen (51%) patients showed partial response (PR). Clinical benefit rate was 95%. PFS at 5 y was 80.8%. In PR cases, median time to response was 10 mo. Longer duration of therapy was significantly associated with the response of PR (P = .007) by univariate analysis. There was no clear association between various clinicopathological factors, including tumor size, location, catenin beta-1 (CTNNB1) mutation status with effect. Only 3 AEs of grade 3/4 were observed. Tumor regrowth after MTX + VBL discontinuation was observed in 5 (20%) of 25 patients. Biweekly administration of MTX + VBL chemotherapy was well tolerated compared with weekly administration, and its efficacy was anticipated in DF patents, although the time needed to achieve a response may be relatively long. The treatment interval should be determined taking into account both the condition of the tumor and the patient's preference.

Risk factors of local recurrence after surgery in extraabdominal desmoid-type fibromatosis: A multicenter study in Japan.

This study was undertaken to clarify the risk factors, including the mutation status of CTNNB1, for the local recurrence after surgery of the rare disease desmoid-type fibromatosis. It was designed as a multiinstitutional joint research project with 7 major centers in Japan participating. The committee members of 7 major medical centers specializing in bone and soft tissue tumors formed this study group to develop clinical care guidelines. Of 196 cases with specimens and medical records collected from the 7 institutions, 88 surgically treated ones were analyzed regarding clinicopathologic prognostic factors including CTNNB1 mutation status. Excluding R2 cases (n = 3), 5-year local recurrence-free survival (LRFS) was 52.9%. No case had received pre- or postoperative radiotherapy. Univariate analysis revealed that extremity location (P < .001) and larger size (8 cm or more, P = .036) were significant adverse risk factors for LRFS. Multivariate analysis indicated that extremity location (P < .001) was a significantly adverse factor in addition to recurrent tumor (P = .041), S45F mutation (P = .028), and R1 surgical margin (P = .039). Preoperative drug treatment, including nonsteroidal antiinflammatory drugs, did not reduce the incidence of local recurrence (P = .199). This is the first study to analyze the factors correlating with outcomes of surgical treatment, including CTNNB1 mutation status, in a relatively large number of cases from an Asian country. Tumor location was found to be the most influential prognostic factor for local recurrence, similar to the results from Europe and North America. The development of more sensitive method(s) for determination of CTNNB1 mutation is a priority for future study.

Is mutation analysis of ß-catenin useful for the diagnosis of desmoid-type fibromatosis? A systematic review.

BACKGROUND: An accurate diagnosis is crucial to determine the treatment modality for desmoid-type fibromatosis, although the histopathological diagnosis is occasionally difficult to make. Many desmoid-type fibromatosis have been reported to have hotspot mutation of ß-catenin gene (CTNNB1). In the present study, we performed a systematic review to verify the usefulness of CTNNB1 mutation analysis in the diagnosis of desmoid-type fibromatosis. METHODS: A literature search from January 1990 to August 2017 was conducted. Three reviewers independently assessed and screened the literature for eligibility and determined the final articles to be evaluated. Data regarding the sensitivity, specificity, accuracy and usefulness of CTNNB1 mutation analysis in the diagnosis of desmoid-type fibromatosis were recorded. We rated each report according to the Grading of Recommendations Development and Evaluation approach. RESULTS: The search yielded 90 studies, seven of which were included after the first and second screenings. The positive rate of CTNNB1 mutation in desmoid-type fibromatosis was 86.8%, but the cohort of six of the seven reports was already diagnosed histopathologically as desmoid-type fibromatosis. Therefore, the usefulness of CTNNB1 mutation analysis in a cohort that is difficult to diagnose histopathologically is not clear in this review. Nevertheless, CTNNB1 mutation showed very high specificity in desmoid-type fibromatosis, indicating the usefulness of CTNNB1 mutation analysis in its diagnosis in combination with histological examination. CONCLUSION: Because the lack of data precludes any useful comparison with histological diagnosis, the evidence level is low. However, considering its specificity, CTNNB1 mutation analysis may be useful in cases in which the histopathological diagnosis is difficult.

Is tumour location a prognostic factor for pharmacological treatment in patients with desmoid-type fibromatosis? a systematic review.

BACKGROUND: The mainstay of the treatment for desmoid-type fibromatoses has been shifting from surgery to drug treatment, making accurate prediction of the efficacy of drug treatment of extreme importance. On the other hand, desmoid-type fibromatoses arise everywhere in the body. The purpose of this systematic review was to address the clinical question of whether tumour location has an impact on the efficacy of drug treatment. METHODS: A literature search from January 1990 to August 2017 was conducted. Four reviewers independently assessed and screened the literature for eligibility and determined the final articles. They rated each report according to the Grading of Recommendations Development and Evaluation approach. Based on the quality of 'Body of Evidence', our clinical guideline committee developed a recommendation for the clinical question. RESULTS: In total, 128 articles were extracted. After the screenings, 5 were chosen for the final evaluation. The drugs used in these articles were one each of toremifene, sorafenib, and methotrexate and vinblastine and of meloxicam. There were no randomized controlled trials, and two prospective and three retrospective case series were included. Therapeutic effects were observed slightly more markedly in extremity using meloxicam or methotrexate and vinblastine. In contrast, the efficacy of toremifene was slightly higher in non-extremity. However, the evidence level of all of the reports was judged to be low. CONCLUSIONS: Considering the low evidence level, we concluded that the site-specific therapeutic effects of drugs could not be confirmed in desmoid-type fibromatoses.

Functional evaluation following deltoid muscle resection in patients with soft tissue sarcoma.

BACKGROUND: The present study aimed to determine functional outcomes in patients undergoing deltoid muscle resection for soft tissue sarcoma. METHODS: Between 2002 and 2014, 18 patients with soft tissue sarcoma of the shoulder who underwent wide resection including the deltoid muscle, and were followed up for more than 12 months, were retrospectively included in the study. In all, 11 patients were male and 7 were female. The median age was 59 years, median follow-up duration was 37 months. The extent of resection of deltoid muscle, with or without rotator cuff damage, reconstruction methods, adjuvant therapy, oncological outcomes, and the International Society of Limb Salvage (ISOLS) score as functional outcomes were analyzed. RESULTS: Six patients underwent total resection, and twelve underwent partial resections of deltoid muscle. The rotator cuff was resected in four patients. Soft tissue reconstruction was performed in 17 patients using a pedicled latissimus dorsi muscle flap. Two local recurrences and three distant metastases occurred during follow-up. Median overall survival was 72 months. The mean ISOLS score was 25.0 points (±4.6points). Univariate analysis revealed that there was no significant difference in ISOLS score regarding the extent of deltoid muscle resection. Multivariate analysis identified only combined resection of the rotator cuff as a significant prognostic factor for poor functional outcomes (P < 0.001). CONCLUSIONS: The extent of resection of the deltoid muscle might not affect the functional outcomes determined by ISOLS score. If the rotator cuff is resected concurrently, satisfactory functional outcomes might not be obtained.

Forced expression of KIAA1199, a novel hyaluronidase, inhibits tumorigenicity of low-grade chondrosarcoma.

Hyaluronan (HA) has been shown to play crucial roles in the tumorigenicity of malignant tumors. Chondrosarcoma, particularly when low-grade, is characterized by the formation of an extracellular matrix (ECM) containing abundant HA, and its drug/radiation resistance has become a clinically relevant problem. This study aimed to evaluate the effects of a novel hyaluronidase, KIAA1199, on ECM formation as well as antitumor effects on chondrosarcoma. To clarify the roles of KIAA1199 in chondrosarcoma, mouse KIAA1199 was stably transfected to Swarm rat chondrosarcoma (RCS) cells (histologically grade 1). We investigated the effects of KIAA1199 on RCS cells in vitro and an autografted model in vivo. HA binding protein (HABP) stainability and ECM formation in KIAA1199-RCS was markedly suppressed compared with that of control cells. No significant changes in messenger RNA expression of Has1, Has2, Has3, Hyal1, or Hyal2 were observed. KIAA1199 expression did not affect proliferation or apoptosis but inhibited migration and invasion of RCS cells. In contrast, the expression of KIAA1199 significantly inhibited the growth of grafted tumors and suppressed the stainability of alcian blue in tumor tissues. Although there was no direct inhibitory effect on proliferation in vitro, induction of KIAA1199 showed the antitumor effects in grafted tumor growth in vivo possibly due to changes in the tumor microenvironment such as inhibition of ECM formation. Forced expression of KIAA1199 exhibits antitumor effects on low-grade chondrosarcoma, which has chemo- and radio-therapy resistant features. Together, KIAA1199 could be a novel promising therapeutic tool for low-grade chondrosarcoma, mediated by the degradation of HA.

Factors contributing to the systemic clearance of infliximab with long-term administration in Japanese patients with Crohn's disease: Analysis using population pharmacokinetics
.

OBJECTIVE: Crohn's disease (CD) is a chronic inflammatory gastrointestinal disease with repeated cycles of exacerbation and remission. Infliximab (IFX), a chimeric anti-TNF-α monoclonal antibody, has been widely used for the treatment of CD. However, no study in Japanese CD patients receiving continuous IFX for more than 1 year has been reported. To avoid therapeutic failure during long-term administration in Japanese CD patients, we evaluated the variable factors of IFX pharmacokinetics and the optimal trough IFX concentration at 8 weeks after administration. MATERIALS AND METHODS: Population pharmacokinetic (PPK) analysis was performed using the nonlinear mixed-effect model based on the IFX serum concentration in 832 samples from 121 patients. A one-compartment model was used to examine interindividual variability in the systemic clearance (CL) of intravenously administered IFX. RESULTS: PPK estimates (estimated value, RSE%) were total clearance (CL: 0.018 L/h, 9.1) and volumes of distribution (Vd: 7.35 L, 12.0). Interindividual variability for CL and Vd of 0.11 and 0.16, respectively, was found. Body weight, antibody to IFX (ATI), and albumin level were factors affecting the IFX CL. IFX CL was greater in the ATI-positive than in the ATI-negative group. CL was also greater in nonremission patients. There was a significant association between the predicted serum IFX trough concentration at 8 weeks and therapeutic response with long-term continuous administration (p < 0.05), with a higher concentration at 8 weeks seen in the remission group. CONCLUSION: Using these variables including body weight, ATI, and albumin level, the IFX dose could be calculated for individual CD patients to achieve the optimal therapeutic range.

Efficacy of low-dose chemotherapy with methotrexate and vinblastine for patients with extra-abdominal desmoid-type fibromatosis: a systematic review.

OBJECTIVE: The treatment modality for desmoid-type fibromatosis has shifted from surgery to conservative treatment. This systematic review aims to evaluate the efficacy of low-dose chemotherapy with methotrexate and vinblastine for patients with extra-abdominal desmoid-type fibromatosis. METHODS: We searched the pertinent literature from January 1990 to August 2017. Two reviewers evaluated and screened the literature independently for eligibility and extracted data. We evaluated the quality of body of evidence and made a recommendation according to the Grading of Recommendations Development and Evaluation methodology. RESULTS: The search yielded 40 studies, 9 of which were included after the first and second screenings. There were three prospective case series but no randomized controlled trials among the nine studies. There was no case-control report (vs. no treatment). According to Response Evaluation Criteria in Solid Tumors criteria, the mean response rate (complete remission or partial response) was 36% (11-57%). Including stable disease, namely, clinical benefit was consistently as high as 85% (69-100%). Mean adverse event rate of G3 or G4 according to CTCAE was 31%. One study reported improvement of pain (87.5%) because of this chemotherapy. CONCLUSION: The efficacy of this chemotherapy was convincing. However, the overall evidence was weak, and this chemotherapy is not covered by insurance in Japan; we only weakly recommend low-dose chemotherapy with methotrexate and vinblastine in patients with extra-abdominal desmoid-type fibromatosis.

MRI characteristics predict the efficacy of meloxicam treatment in patients with desmoid-type fibromatosis.

INTRODUCTION: This study aimed to determine the clinical significance of MRI characteristics as a possible predictor of responsiveness to meloxicam treatment in patients with desmoid-type fibromatosis (DF). Additionally, it analysed the correlation between CTNNB1 mutation status and signal intensity of MRI. METHODS: Forty-six patients consecutively treated with meloxicam composed this study. The low-intensity area (LIA) on T2-weighted MRI was determined. We divided patients into two groups based on the efficacy of meloxicam: a clinical benefit group (CB group, including CR: complete response; PR: partial response; and SD: stable disease) and non-clinical benefit group (NB group, including PD: progressive disease). Correlations of the efficacy with LIA and CTNNB1 mutation status with LIA were investigated. RESULTS: In total, 11, 17 and 18 patients showed PR, SD and PD, respectively. The mean LIA ratio before treatment was significantly higher (P < 0.001) in the CB group than in the NB group. For predicting the efficacy, sensitivity was 68%, and specificity was 89% when setting the cut-off value as 20% for LIA. Mean changes in the LIA ratio before and after treatment were significantly higher (P = 0.01) in the CB group than in the NB group. Mean LIA ratio before treatment was significantly lower (P < 0.001) in the S45F mutation group than in the other mutation group. In multivariate analysis, the LIA ratio before treatment was a significant predictor of responsiveness (P = 0.02). CONCLUSIONS: MRI characteristics were a useful predictor of the efficacy of meloxicam in DF patients. It may be possible to predict the clinical outcome more accurately when combined with other factors, such as CTNNB1 mutantion status.

Long-term effect of NUDT15 R139C on hematologic indices in inflammatory bowel disease patients treated with thiopurine.

BACKGROUND AND AIM: A missense variant of the nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15) gene (R139C) predisposes Asian patients with inflammatory bowel disease (IBD) to thiopurine-induced leukopenia. This study evaluates the long-term effect of NUDT15 R139C heterozygosity on hematological parameters during thiopurine administration. METHODS: We enrolled 83 Japanese IBD patients who were on anti-tumor necrosis factor-α agents and had used thiopurine. NUDT15 R139C was genotyped by polymerase chain reaction. We retrospectively reviewed patient clinical charts to collect data on white blood cell (WBC) count, mean corpuscular volume (MCV), hemoglobin, and platelet count during the 24 months following thiopurine initiation. RESULTS: The included patients had either Crohn's disease (54; 65.1%) or ulcerative colitis (29; 34.9%). Genotyping of NUDT15 R139C identified 62 patients (74.7%) of genotype C/C and 21 (25.3%) of genotype C/T. The median dose of thiopurine was lower in the C/T group than in the C/C group after starting thiopurine. At 6 months, the mean WBC count of the C/T group became significantly lower than that of the C/C group (P = 0.008) and remained lower through the 24 months. The C/T group developed grade 2-4 leukopenia by 6 months, which persisted through 12-24 months. The mean MCV in the C/T group became higher than that of the C/C group after 3 months. CONCLUSIONS: NUDT15 R139C heterozygosity affected the WBC count and MCV for 24 months after thiopurine administration. Our results indicate that careful monitoring of leukopenia and dose adjustment are necessary throughout treatment in IBD patients heterozygous for the NUDT15 R139C.

Is immunohistochemical staining for ß-catenin the definitive pathological diagnostic tool for desmoid-type fibromatosis? A multi-institutional study.

Immunohistochemical staining with anti-ß-catenin antibody has been applied as a diagnostic tool for desmoid-type fibromatoses (DFs). In recent years, specific gene mutation (CTNNB1) analysis has also been reported to be useful for diagnosis of DF; however, the association between CTNNB1 mutation status and immunohistochemical staining pattern of ß-catenin is rarely reported. The purposes of this study are to clarify the relationship of the staining pattern of ß-catenin with the CTNNB1 mutation status and various clinical variables, and to investigate the significance of immunohistochemical staining of ß-catenin in cases diagnosed as DF. Between 1997 and 2017, 104 cases diagnosed as DF from 6 institutions in Japan were enrolled in this study: Nagoya University, National Cancer Center Hospital, Niigata University, Okayama University, Kyushu University, and Cancer Institute Hospital. For all cases, immunohistochemical staining of ß-catenin and gene mutation analysis of CTNNB1 were performed. Of 104 cases, 87 (84%) showed nuclear staining of ß-catenin, and 95 (91%) showed positive staining in the cytoplasm. The proportion of cases showing strong nuclear staining of ß-catenin was significantly higher in the cases with S45F than in those with T41A or wild type. The proportion of cases stained strongly in the cytoplasm rather than in the nucleus was significantly higher in the group of T41A than that of S45F or wild type. Among 17 cases in which nuclear immunostaining was absent, CTNNB1 mutation was observed in 5 cases (29.4%). There were unignorable cases of DF with negative ß-catenin immunostaining despite a definitive clinical and pathological diagnosis of DF and/or positive CTNNB1 mutation.