[Diagnostic challenge of biphenotypic sinonasal sarcoma]. / Défi diagnostique du sarcome nasosinusien biphénotypique.

Sinonasal biphenotypic sarcoma has recently been described and included in the 2017 WHO classification. It is a low-grade sarcoma which is characterized by PAX3 rearrangements. It remains a diagnostic challenge because of its scarcity, and its considerable histologic overlap with other cellular spindle cell neoplasms. The histologic features, the immunoprofile and the main differential diagnoses of sinonasal biphenotypic sarcoma are presented through a case.

A Novel ALK-THBS1 Fusion in a Laryngeal Inflammatory Myofibroblastic Tumour: A Case Report and Literature Review.

Inflammatory myofibroblastic tumor (IMT) is an uncommon neoplasm most frequently seen in the abdomino-pelvic region and lungs of children and young adults. Laryngeal tumors are rare. We present a case of a 23-year-old patient with a 5 month history of laryngitis and aphonia unresolved by corticotherapy. Laryngoscopy revealed a small, non-ulcerated, subepithelial, polypoid mass arising from the right vocal cord. The diagnosis of IMT with ALK expression was supported by histopathologic and molecular analysis. The THBS1 fusion partner was identified by RNA-sequencing analysis for the first time in a laryngeal IMT. This fusion partner has only been identified in six uterine IMTs thus far. Conservative excision of the lesion yielded excellent functional results for the patient. The voice was preserved and no recurrences were seen after 6 months of follow-up.

Diagnostic Reliability of Leptomeningeal Disease Using Magnetic Resonance Imaging.

Brain metastases are seen in 20%-50% of patients with metastatic solid tumors. On the other hand, leptomeningeal disease (LMD) occurs more rarely. The gold standard for the diagnosis of LMD is serial cerebrospinal fluid (CSF) analyses, although in daily practice, the diagnosis of LMD is often made by neuroimaging. Leptomeningeal metastases (LM) have been a relative contra-indication to radiosurgery. It can be noted that focal LMD can be difficult to distinguish from a superficially located/cortical-based brain metastasis which is not a contra-indication for radiosurgery. Hence, justifying the need of a reliable diagnosis method. The goal of this study was to determine the inter-observer reliability of contrast-enhanced magnetic resonance imaging (gdMRI) in the differentiation of focal cortical-based metastases from leptomeningeal spread. This is a retrospective review of a prospectively collected database of patients with brain metastases. A total of 42 cases with superficial lesions were selected for review. Additionally, eight control cases demonstrating deep and/or white-matter based lesions were included in the study. Three neuroradiologists and three radiation oncologists were asked to review each study and score the presence of LM. Inter-observer agreement was calculated using group-derived agreement coefficients (Gwet's AC1 and Gwet's AC2). Pair-wise inter-observer agreement coefficients never reached substantial values for trichotomized outcomes (LMD, non-LMD or indeterminate) but did reach a substantial value in a minority of cases for dichotomised outcomes (LMD or non-LMD). The control subgroup analysis revealed substantial agreement between most pairs for both trichotomized and dichotomised outcomes. We observed low inter-observer agreement amongst specialists for the diagnosis of focal LMD by gdMRI. Neuroimaging should not be relied upon to make treatment decisions, notably to deny patients radiosurgery.

Primary cardiac B cell lymphoma: Manifestation of Felty's syndrome or TNFα antagonist.

Primary cardiac B cell lymphoma is rare. To date, fewer than 90 cases have been described in the literature. We report a 67-year-old woman with a 30-year history of rheumatoid arthritis, who had received treatment with leflunomide for 10 years and infliximab for 2 years. Secondary Felty's syndrome appeared. She was admitted to the hospital for abdominal pain. Investigations disclosed a 5cm cardiac mass in the right atrium. Histopathologic examination of tissue specimens obtained at surgical myocardial biopsy demonstrated primary cardiac B cell lymphoma. The other iatrogenic lymphoproliferative disorders are reviewed. This lesion might be a manifestation of long term TNFα antagonists treatment.

White matter lesions in FTLD: distinct phenotypes characterize GRN and C9ORF72 mutations.

Frontotemporal lobar degeneration (FTLD) has a high frequency of genetic forms; the 2 most common are GRN (progranulin) and C9ORF72 mutations. Recently, our group reported extensive white matter (WM) lesions in 4 patients with FTLD caused by GRN mutation, in the absence of noteworthy cardiovascular risk factors,(1) in line with other studies in GRN mutation carriers.(2,3) Here we compared the characteristics of frontal WM lesions in patients with behavioral variant of FTLD (bv-FTLD) caused by GRN and C9ORF72 mutations.