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Audrey Rousseau

Publications and source records attributed to Audrey Rousseau.

7 recordsLinked to original sources
PubMed2006

Expression of oligodendroglial and astrocytic lineage markers in diffuse gliomas: use of YKL-40, ApoE, ASCL1, and NKX2-2.

The phenotypic heterogeneity of astrocytic and oligodendroglial tumor cells complicates establishing accurate diagnostic criteria, and lineage-specific markers would facilitate diagnosis of glioma subtypes. Based on data from the literature and from expression microarrays, we selected molecules relevant to gliogenesis and glial lineage specificity and then used immunohistochemistry to assess expression of these molecules in 55 diffuse gliomas, including 8 biphasic oligoastrocytomas, 21 oligodendrogliomas (all with 1p/19qloss), 21 astrocytomas, and 5 glioblastomas. For the astrocytic lineage markers (GFAP, YKL-40, and ApoE), GFAP expression was significantly higher in the astrocytic component of oligoastrocytomas compared with the oligodendroglial part; similar patterns were detected for YKL-40 and ApoE, although the differences were not significant. GFAP, YKL-40, and ApoE reliably distinguished grade II-III oligodendrogliomas from grade II-IV astrocytomas (p < 0.0001, p = 0.002, and p < 0.0001, respectively). Among the oligodendroglial lineage markers (Olig2, Sox10, ASCL1, and NKX2-2), ASCL1 and NKX2-2 displayed significantly different immunostaining between oligodendrogliomas and astrocytomas (p = 0.017 and 0.004, respectively), but none clearly differentiated between the 2 glial populations of oligoastrocytomas. In addition to GFAP, therefore, YKL-40, ApoE, ASCL1, and NKX2-2 represent promising tumor cell markers to distinguish oligodendrogliomas from astrocytomas.

Adipokines↗
PubMed2005

Survivin expression in ganglioglioma.

Gangliogliomas are unusual central nervous system (CNS) neoplasms occurring mainly in children and young adults and inducing chronic pharmacoresistant epilepsy. These are usually well differentiated neuroepithelial tumors composed of neurons in association with neoplastic glial cells. Gangliogliomas present with favorable outcome. However, some may recur and/or progress to anaplasia and be associated with a dismal prognosis. Since histopathological features do not consistently correlate with clinical outcome, reliable prognostic factors have yet to be defined in gangliogliomas. Survivin is an anti-apoptotic protein whose expression has been found to be of prognostic significance in many human cancers, including gliomas. The objective of this study was to assess survivin expression using immunohistochemistry in 15 gangliogliomas. Ten lesions were low-grade neoplasms whereas 5 were high-grade tumors. Survivin expression appeared restricted to the neoplastic glial component and was detected in 6/15 gangliogliomas. Two additional tumors expressed survivin upon relapse. Half survivin expressing lesions displayed less than 1% immunoreactive cells. Survivin expression in more than 5% neoplastic glial cells was detected only in malignant and/or recurrent gangliogliomas. Extended lifespan in survivin expressing cells might enhance aggressive behavior in these tumors through accumulation of mutations, thereby allowing progression to malignant phenotypes. Survivin expression may carry a negative prognostic value in gangliogliomas.

Adolescent↗
PubMed2005

[Mycoses of the head and neck].

In recent years, mycoses have emerged as important infections in clinical practice. This phenomenon is explained by the ever growing number of immunocompromised patients and the increasing number of people travelling in areas where fungal diseases are endemic. Head and neck infections are common in disseminated mycoses and may simulate carcinoma or cause upper airway obstruction. The most frequent causative yeasts or yeast-like organisms include Candida albicans, Cryptococcus neoformans, Histoplasma capsulatum var capsulatum, Blastomyces dermatitidis, Paracoccidioides brasiliensis and Coccidioides immitis. Other causative fungal pathogens include Aspergillus fumigatus and less frequently, Rhizopus oryzae and Rhinosporidium seeberi. Since in most cases their pathophysiology is similar, those microorganisms share a common clinical pathological presentation. Symptoms such as dysphonia or dysphagia associated with hyperplastic and ulcerative lesions on endoscopic examination should prompt biopsies. A purulent or granulomatous inflammatory tissue reaction with pseudoepitheliomatous hyperplasia warrants caution since it may lead to a mistaken diagnosis of carcinoma. The pathologist must look carefully for microorganisms with Grocott and PAS stains. The causative agent can be identified if the pathologist is aware of the risk. Positive culture is needed to institute adequate treatment.

Aspergillosis↗
PubMed2005

Primary intracranial melanocytic tumor simulating pituitary macroadenoma: case report and review of the literature.

OBJECTIVE AND IMPORTANCE: Primary intracranial melanocytic tumors are rare lesions, sellar ones being even more exceptional. So far, six melanomas and two melanocytomas have been described in an intrasellar and/or suprasellar location. CLINICAL PRESENTATION: We report on the case of a 25-year-old Caucasian woman presenting with a 4-year history of amenorrhea and an intrasellar mass with suprasellar extension suggestive of a pituitary macroadenoma. INTERVENTION: A gross subtotal resection of a hemorrhagic tumor was performed. Histological examination revealed melanin-laden pleomorphic tumor cells that tested positive for HMB-45 and S-100 and negative for cytokeratins, thus demonstrating that the tumor was a melanocytic neoplasm. An extensive workup failed to find evidence of any other primary site. The patient received no further treatment and is alive and well after 24 months of follow-up. CONCLUSION: Primary sellar melanocytic neoplasms are extremely rare lesions and present with few differential diagnoses. Deciding whether the tumor is best classified as a melanocytoma or a melanoma may prove difficult. Wide histological variations in both melanocytomas and melanomas render careful consideration of the clinical, radiological, and gross features essential in distinguishing one from the other.

Adenoma↗
PubMed2004

Lethal pulmonary hemorrhage caused by a fulminant Stenotrophomonas maltophilia respiratory infection in an acute myeloid leukemia patient.

Stenotrophomonas maltophilia (Sm) pneumonia in immunocompromized hosts is an increasingly common nosocomial infection. Even though resistant to multiple antimicrobials, this gram-negative bacteria usually does not present with a fulminant course leading to a fatal hemorrhagic respiratory infection in neutropenic patients. We report here the case of a 63-year-old woman treated by intensive chemotherapy for acute myeloid leukemia (AML) who presented while severely neutropenic and thrombocytopenic a Sm pulmonary infection with hemoptysis leading to death in 48 h. The bronchoalveolar lavage (BAL) performed shortly before death was highly hemorrhagic and contained a striking amount of extra- and intra-cellular pathogens. Blood and BAL cultures grew S. maltophilia. Post-mortem examination revealed bilateral extensive intra-alveolar hemorrhage (IAH) associated with a great amount of microorganisms and severe bone marrow aplasia was observed without evidence of leukemia residual disease. Sm pneumonia usually does not evolve into such a devastating clinical picture although infections due to the bacteria are known to be associated with high morbidity and mortality. So far, the present observation is the fourth similar case reported in the literature. Even though an early diagnosis and an adequate antibiotic prescription may improve Sm infection prognosis, S. maltophilia proves difficult to eradicate due to a high resistance rate in part intrinsic but also in part acquired.

Acute Disease↗
PubMed2003

Spectrum of paraneoplastic neurologic disorders in women with breast and gynecologic cancer.

We conducted the current review of the paraneoplastic neurologic syndromes (PNSs) associated with gynecologic and breast carcinomas to describe their clinical and immunologic characteristics and their relative frequency. We retrospectively reviewed 92 patients whose serum was sent to our laboratories to detect onconeural antibodies and who were diagnosed as having PNSs associated with breast or gynecologic tumors. PNSs were defined as "definitive" and "possible" (atypical PNS, no onconeural antibodies, and no improvement after tumor treatment). Forty-nine patients had breast and 43 had gynecologic cancer. Sixty-three patients had onconeural antibodies (50 Yo-ab, 5 Hu-ab, 5 Ri-ab, and 3 amphiphysin-ab). Cerebellar ataxia represented 57 (62%) of all PNSs and was associated with anti-Yo in 88%. All Yo-abnegative patients had breast cancer; 4 of them had a mild cerebellar syndrome that improved after tumor treatment. Sensorypredominant neuropathies were present in 17 (18%) patients. Seven of them had Hu-ab (5) or amphiphysin-ab (2). Other PNSs were opsoclonus-myoclonus syndrome (4 cases, Ri-ab in 2), sensorimotor neuropathy (4 cases), paraneoplastic encephalomyelitis (4 cases, Ri-ab in 3), paraneoplastic retinopathy (2 cases), amyotrophic lateral sclerosis (2 cases), stiff-person syndrome (1 with amphiphysin-ab), and limbic encephalitis (1 case). All patients with gynecologic cancer presented definitive PNS, and onconeural antibodies were diagnosed in 93% of them. In contrast, 20% of PNSs associated with breast cancer were defined as possible and the incidence of onconeural antibodies was 51%, excluding the 2 patients with paraneoplastic retinopathy in whom antiretinal antibodies were not analyzed. In patients with possible PNS, a coincidental association between the tumor and the neurologic disorder cannot be excluded.

Aged↗