The role of radiation therapy in pediatric mucoepidermoid carcinomas of the salivary glands.

OBJECTIVE: To investigate the role of radiation therapy in rare salivary gland pediatric mucoepidermoid carcinoma (MEC). STUDY DESIGN: A French multicenter retrospective study (level of evidence 4) of children/adolescents treated for MEC between 1980 and 2010 was conducted. RESULTS: Median age of the 38 patients was 14 years. Parotid subsite, low-grade, and early primary stage tumors were encountered in 81%, 82%, and 68% of cases, respectively. All except 1 patient were treated by tumoral surgical excision, and 53% by neck dissection (80% of high grades). Postoperative radiation therapy and chemotherapy were performed in 29% and 11% of cases. With a median 62-month follow-up, overall survival and local control rates were 95% and 84%, respectively. There was 1 nodal relapse. Lower grade and early stage tumors had better survival. Postoperative radiation therapy and chemotherapy were associated with similar local rates. Patients with or without prior cancer had similar outcomes. CONCLUSIONS: Pediatric salivary gland MEC carries a good prognosis. Low-intermediate grade, early-stage tumors should be treated with surgery alone. Neck dissection should be performed in high-grade tumors. Radiation therapy should be proposed for high grade and/or advanced primary stage MEC. For high-grade tumors without massive neck involvement, irradiation volumes may be limited to the primary area, given the risk of long-term side effects of radiation therapy in children. Pediatric MEC as second cancers retain a similar prognosis. Long-term follow-up is needed to assess late side effects and second cancers.

[Glyoxal: a possible polyvalent substitute for formaldehyde in pathology?]. / Le glyoxal : un possible substitut polyvalent du formaldéhyde en anatomie pathologique ?

The quest for formaldehyde substitutes is motivated by two fundamental developments: the OSHA regulation standard declaring it hazardous and advocating its substitution with less dangerous chemicals and the fact that formalin is a poor preserver of nucleic acids. Among the non-alcoholic formalin substitute, glyoxal has been hailed as the best alternative. In this work, we showed that glyoxal-containing fixatives are not plausible polyvalent substitution options.

[Detection of apoptosis in vivo: comparison of different methods in histological sections of subcutaneous xenografts of HT29 human colon adenocarcinoma]. / Quantification de l'apoptose in vivo: comparaison de méthodes de détection sur coupes histologiques de tumeurs xénogreffées issus de la lignée cellulaire humaine d'adénocarcinome colique HT-29.

UNLABELLED: Apoptosis detection in histological section is very important, but usual methods (TUNEL and morphologic changes) are controversial. Immunohistochemical stains of activated proteins during apoptosis improve detection of cell death in tissue sections. Activated caspase-3 and cleaved cytokeratin-18 are more and more used. OBJECTIVE: This study compared immunohistochemical markers (activated caspase-3, cleaved cytokeratin-18 and two antibodies not yet evaluated: activated caspase-7 and cleaved PARP-1), cellular morphology and TUNEL. MATERIAL AND METHODS: Tumour xenografts of the human colon cancer cell line HT29 were used, treated by photodynamic therapy, to obtain large numbers of cells undergoing apoptosis. Apoptotic cells were quantified and apoptotic indices were determined for each marker. RESULTS: Comparison of apoptosis index indicated statistically best sensibility with activated-caspase-3 and cleaved-cytokeratin-19. CONCLUSION: Immunohistochemistry for activated caspase-3 and cleaved cytkeratin-18 appear to be an easy, sensitive, and reliable method for detecting and quantifying apoptosis in this model. There are therefore recommended for the detection and quantification of apoptosis in tissue sections. Other markers as cleaved PARP-1 and activated caspase-7 can be an interessant solution: advantages and inconvenience for each methods are exposed.

Small vessel replacement by human umbilical arteries with polyelectrolyte film-treated arteries: in vivo behavior.

OBJECTIVE: The aim of this study was to evaluate the patency of human umbilical arteries treated with polyelectrolyte multilayers (PEMs) after rabbit implantation. BACKGROUND: The development of small-caliber vascular substitutes with high patency after implantation remains a real challenge for vascular tissue engineering. METHODS: Cryopreserved human umbilical arteries were enzymatically de-endothelialized and the luminal surfaces were coated with poly(styrene sulfonate)/poly(allylamine hydrochloride) (PSS/PAH) multilayers. The PEM-untreated arteries and PEM-treated rabbit carotids were used as graft control. The native rabbit carotids were bypassed by grafts. RESULTS: The Doppler ultrasound evaluation, performed in vivo, showed that all PEM-treated grafts remained patent during the full experimental period, whereas after only 1 week, no blood circulation was detected in untreated arteries. Scanning electron microscopy and histological graft examination showed pervasive thrombus formation on the luminal surface of untreated arteries after 1 week and clean luminal surface for treated arteries for at least up to 12 weeks. The arterial wall cells were identified through alpha-smooth muscle actin alphaupsilondelta platelet endothelial cell adhesion molecule-1 expression. The smooth muscle cells positive to alpha-smooth muscle actin were identified in adventitia and media and the endothelial cells positive to platelet endothelial cell adhesion molecule in intima. Von Kossa reaction didn't reveal any calcium salt deposits on the wall arteries, suggesting a good wall remodelling with no sign of graft rejection. CONCLUSIONS: The in vivo evaluation of human umbilical arteries treated with PSS/PAH multilayers demonstrated a high graft patency after 3 months of implantation. Such modified arteries could constitute a useful option for small vascular replacement.

Immunohistochemical markers to distinguish between hemangioblastoma and metastatic clear-cell renal cell carcinoma in the brain: utility of aquaporin1 combined with cytokeratin AE1/AE3 immunostaining.

Distinguishing hemangioblastomas from metastatic clear-cell renal cell carcinomas (CCRCCs) in the brain is a diagnostic challenge owing to similar clinical and morphologic presentations. Inhibin-alpha and aquaporin1 were shown as positive markers of hemangioblastoma, but are not totally reliable distinguishing hemangioblastoma from metastatic CCRCC. This study shows that the diagnosis can be achieved using a combination of markers. To identify the panel of markers useful for this differential, 67 hemangioblastomas and 34 metastatic CCRCCs were analyzed using a panel of antibodies including aquaporin1, inhibin-alpha, D2-40, cytokeratin AE1/AE3, epithelial membrane antigen, and CD10. The study confirms the usefulness of aquaporin1 (97% sensitivity, 83% specificity) and inhibin-alpha (88% sensitivity, 79% specificity) as positive markers of hemangioblastoma and shows that aquaporin1 is a superior positive marker versus inhibin-alpha for the differential. Positivity of tumor cells with cytokeratin AE1/AE3 is the signature of a metastatic CCRCC (100% specificity, 88% sensitivity) and CD10 expression as well (100% specificity, 79% sensitivity). The combined use of aquaporin1 and AE1/AE3 yields a high degree of sensitivity and specificity to differentiate between hemangioblastoma and metastatic CCRCC. All tumors but one aquaporin1 positive and cytokeratin AE1/AE3 negative (65/66) correspond to hemangioblastomas (97% sensitivity, 97% specificity, 98.5% diagnostic positive predictive value). Tumors with the opposite profile, aquaporin1 negative, and cytokeratin AE1/AE3 positive, (25/25), correspond to metastatic CCRCC (74% sensitivity, 100% specificity, 100% diagnostic positive predictive value). In summary, aquaporin1 is the most sensitive positive marker of hemangioblastoma. Despite its moderate specificity, when used in combination with epithelial marker AE1/AE3, it allowed to reliably distinguish hemangioblastoma from metastatic CCRCC.

Contribution of NADH dehydrogenase subunit I and cytochrome C oxidase subunit I sequences toward identifying a case of human coenuriasis in France.

Coenuriasis is a parasitic disease induced by larval taeniid tapeworms that is rarely observed in humans. In December 2005, a case was diagnosed in Nancy, France, after surgical excision of a cyst on a 24-yr-old woman returning from the Côte d'Ivoire. Morphological and epidemiological criteria suggested that the infection was due to Taenia serialis. Molecular analysis of NADH dehydrogenase subunit I (NDI) and cytochrome c oxidase subunit I (COI) sequences was also in favor of T. serialis identification, but the absence of available genetic data on T. brauni and T. glomeratus and the small number of published sequences for T. serialis and T. multiceps must be considered with caution. The NDI partial sequences presented more variations within species of Taenia than the COI sequences, which make them more useful targets for species identification and analysis of intraspecific polymorphisms. The present study points to the usefulness of molecular biology tools to help make up for the shortcomings of the commonplace parasitological diagnosis for coenuriasis.

[Primary clear cell sarcoma of the ileum]. / Sarcome à cellules claires primitif de l'iléon.

Clear cell sarcoma or malignant melanoma of soft tissue is a high-grade sarcoma with melanocytic differentiation, essentially involving tendons and aponeuroses of distal extremities in young adults. Visceral locations are exceptional and only 8 cases involving the gastrointestinal tract are reported in the literature. We present a case of an ileal clear cell sarcoma discovered in a 26-year-old woman. Moreover, we emphasize on the diagnosis difficulties of this rare type of sarcoma, characterized by the specific translocation t(12;22)(q13;q12).

[Molecular consequences of fixation and tissue processing: the examples of nucleic acids and proteins]. / Les conséquences moléculaires de la fixation et de l'inclusion: exemple des acides nucléiques et des protéines.

The scientific usefulness of the molecular data obtained from tissue analysis is related directly to the quality of the tissue specimen. The most ideal tissue specimen is the one that carries a complete and unaltered representation of the tissue in vivo. The aim of this review is to provide an overview of the effects of fixation and tissue processing on the content and integrity of nucleic acid and proteins.

Mucoepidermoid carcinoma of salivary glands in the pediatric age group: 18 clinical cases, including 11 second malignant neoplasms.

BACKGROUND: Salivary gland tumors represent 1% of head and neck tumors, with only 5% of these occurring in patients younger than 20 years. Mucoepidermoid carcinoma (MEC) is one of the most frequent salivary gland cancers among adults and children. METHODS: This survey was conducted among 34 French pediatric oncology departments. From 1980 to 2000, 18 cases were reported. RESULTS: Treatment included surgery or radiotherapy, or both. The 5-year survival rate was 93.7%. Eleven patients had been previously treated by radiotherapy and/or chemotherapy for a first malignant tumor, specifically, lymphoid leukemia (n = 4), lymphoma (n = 3), brain tumor (n = 2), sarcoma (n = 1), and retinoblastoma (n = 1). CONCLUSIONS: MEC is very rare in the pediatric age group. Treatment involves surgical removal of the tumor plus radiotherapy, according to histologic staging. MEC has a good prognosis in young patients. The survival rate does not differ in the subgroup of patients with MEC as a secondary tumor.

[Systemic metastasis at the time of diagnosis of a glioblastoma]. / Glioblastome avec métastases systémiques d'emblée.

Metastatic gliomas are quite rare. We report a case of glioblastoma multiforme with bone marrow metastasis at the time of diagnosis, revealed by a bicytopenia. An autopsy was performed and several visceral metastases were discovered in the lung, the mediastinal lymph nodes and in the spleen.