[Neurogenic spindle-cell tumors of the mediastinum: two cases]. / Tumeurs nerveuses à cellules fusiformes du médiastin: deux observations.

INTRODUCTION: Neurogenic tumors can develop from neural cells in any location. They are commonly found, however, in the mediastinum, most often in its posterior compartment. Neurogenic tumors can be benign or malignant. In the anterior compartment, they must be distinguished from their differential diagnoses. CASES: We report one case of a malignant peripheral nerve sheath tumor in the posterior mediastinum of a 29-year-old man and another of a schwannoma of the anterior mediastinum, in an 82-year-old woman. DISCUSSION: Neurogenic tumors of spindle-shaped cells in the mediastinum are generally benign, but can be malignant. Often asymptomatic, they are usually detected on standard pulmonary radiography, but computerized tomography is necessary, supplemented by magnetic resonance imaging, especially for posterior mediastinal tumors, to provide additional information and to assess its possible extension to adjacent structures. Radiographic, clinical, and especially histopathological features are essential for diagnosis.

[Solitary fibrous tumor of the urinary bladder]. / Tumeur fibreuse solitaire de la vessie.

INTRODUCTION: A solitary fibrous tumor is a rare circumscribed neoplasm that was long known in the pleura and has now described in many organs and soft tissues. Prognosis is favorable after complete excision. CASE: We report a solitary tumor fibrous located in the bladder of a 38-year-old man with dysuria and a palpable abdominal mass. DISCUSSION: Solitary fibrous tumors are reported very rarely in the urinary bladder. They may mimic other nonepithelial tumors in this site. Diagnosis based only on pathological features is difficult. When complete excision is possible, prognosis is generally good. Outcome is more serious in approximately 10-20% of cases, and strict follow-up is required.

[Sinonasal mucosal malignant melanoma]. / Mélanomes des muqueuses nasosinusiennes.

INTRODUCTION: Mucosal melanomas are rare tumors, and primary sinonasal malignant melanomas uncommon tumors that are frequently misclassified. Differential diagnosis should rule out other sinonasal malignancies, including carcinoma, lymphoma, sarcoma, and olfactory neuroblastoma. CASE: We report two new cases of sinonasal melanoma. One involved a 68-year-old man being followed for chronic sinusitis, despite antibiotics; he presented a tumor of the right nasal cavity. The second case was that of a 77-year-old woman, referred for painful gingival swelling shown to involve osteolytic growth in the left maxillary sinus. In both cases, pathologic examination of the biopsy samples concluded that these were sinonasal malignant melanomas. DISCUSSION: Histologically, the diagnosis is very difficult because of the polymorphic features of this tumor, and immunohistochemical studies are very important. The relative inaccessibility of the mucosa to self-examination often delays diagnosis and leads to late detection and poor prognosis.

[Diagnosis of Mycobacterium genavense infection by INNO-LiPA MYCOBACTERIA Amplification v2]. / Infections à Mycobacterium genavense diagnostiquées par le test INNO-LiPA MYCOBACTERIA Amplification v2.

INTRODUCTION: Diagnosis of atypical mycobacterial infections can be facilitated by molecular biology techniques. CASES: Two severely immunodepressed patients were admitted for deterioration of their general health status. Bacteriological analysis of histopathologic fragments showed the presence of acid- and alcohol-resistant bacilli. INNO-LiPA MYCOBACTERIA Amplification v2 made it possible to diagnose Mycobacterium genavense infection. COMMENTS: M. genavense is a slow-growing atypical mycobacterium. The molecular biology techniques used by INNO-LiPA MYCOBACTERIA V2 permit its swift identification.

Follicular dendritic cell sarcoma of the tonsil: a case report.

Follicular dendritic cell sarcomas of the tonsil are very rare tumors. Only 10 cases have been published in the English-language medical literature. We present an additional case that occurred in a 27-year-old woman. She presented with a tumor of the right tonsil. Histological sections of tonsillar biopsies and tonsillectomy suggested that this tumor was a nerve sheath tumor or a malignant melanoma. Histological examination and immunohistochemical study were reviewed. The final diagnosis was follicular dendritic cell sarcoma. She underwent a transoral resection of the right oropharynx with ipsilateral selective neck dissection and postoperative irradiation. We emphasize the difficulties in diagnosing this type of tumor. The use of monoclonal specific markers is required to avoid misdiagnosis. We discuss therapeutic methods for this rare tumor for which optimal treatment has not yet been defined.

Primitive neuroectodermal tumor of the stomach.

Ewing sarcoma/primitive neuroectodermal tumor is classically a tumor of the soft tissue or bone in children and young adults, but several cases have been described in patients of all ages. Within the last decade, the clinicopathologic spectrum of Ewing sarcoma/primitive neuroectodermal tumor has been markedly expanded by recognition that the tumor may also have a visceral origin. We describe a case of primitive neuroectodermal tumor arising in the stomach of a 66-year-old woman. The neoplasm was excised using a radical surgical procedure. Microscopically, the tumor was made up of solid nests and sheets of round cells. Immunohistochemically, the tumor cells showed immunoreactivity for CD99, S100, neuron-specific enolase, and vimentin. A multiplex real-time polymerase chain reaction assay detected an EWS-ERG fusion. To our knowledge, this is the first description of a primitive neuroectodermal tumor arising in the stomach.

Rapid identification of Mycobacterium genavense with a new commercially available molecular test, INNO-LiPA MYCOBACTERIA v2.

We report a rare mesenteric localized Mycobacterium genavense infection in a severely immunocompromised human immunodeficiency virus-infected patient. An INNO-LiPA MYCOBACTERIA v2 test was performed directly on biopsy samples. This new molecular tool could be used for simultaneous identification of mycobacterium species from human specimens, but other studies are needed to validate our first results.

[An unusual mediastinal malignant tumor: thymic carcinoma]. / Une tumeur maligne rare du médiastin: le carcinome thymique.

Thymic carcinoma is a relatively rare neoplasm. Current incidence is difficult to assess. There is some controversy regarding its definition and its diagnostic criteria. We report a case of epidermoid carcinoma in a 48-year-old man located in the thymus area of the anterior mediastinum. Clinicopathological features and prognosis are reviewed.