Assessment of MYCN amplification status in Tunisian neuroblastoma: CISH and MLPA combining approach

Background: Neuroblastoma [NB] shows a complex combination of genetic aberrations. Some of them represent poor genetic prognosis factors that require specific and intensive chemotherapy. MYCN amplification consists of the major bad outcome prognostic factor, it is indeed frequently observed in aggressive neuroblastomas. To date different methods are used for MYCN status detection

Objectives: The primary aim of our study was to provide a critical assessment of MYCN status using 2 molecular techniques CISH and MLPA. We also focused on the correlation between neuroblastoma genetic markers and patient's clinical course among 15 Tunisian patients

Methods: we developed a descriptive study that includes 15 pediatric Tunisian patients referred to our laboratory from 2004 to 2011. We reported the analysis of fresh and FFPE NB tumors tissues

Results:No significant correlation was found between COG grade and patients overall survival. Assessment of NMYC gene copy number by kappa statistic test revealed high concordance between CISH and MLPA tests [kappa coefficient = 0.02]

Conclusion: Despite misdiagnosing of MYCN status fewer than 5 copies, MLPA remains an effective molecular technique that enables a large panel of genomic aberrations screening. Thus combining CISH and MLPA is an effective molecular approach adopted in our laboratory. Our results allow pediatric oncologists to set up the first Neuroblastoma therapeutic strategy based on molecular markers in Tunisia

[Epidemiological, clinical features therapeutic results and evolution of gastrointestinal stromal tumour: about 25 cases]

Gastrointestinal stromal tumors [GIST] are mesenchymal tumors occuring in the majority of cases in the stomach and small intestine, rarely in rectum, colon, esophagus or mesentery. They are derived from cells of cajal or their precursor, and are typically CD117/KIT + [95%], CD34 + [70%]. aims: is to study the epidemiological, clinical, therapeutic and evolution of astrointestinal stromal tumors. Retrospective study including all patientswith the diagnosis of GIST supported in the department of gastroenterology and surgery in universital hospital of Monastir. 25 patients were included, 12 men and 13 women with an average age of 60.5 years. Digestive symptomatology was dominated by gastrointestinal bleeding [n = 12] and abdominal pain [n = 12]. The tumor was discovered incidentally in two patients. The small intestine was the most common site of the tumor [n = 10], followed by the stomach in 9 patients, rectum in two patients, the colon [n = 1], the bulb of water [n = 1], duodenum [n = 1] and liver in a patient. The tumor size ranged from 0.8 to 24 cm. GIST was localized in 16 patients, in whom therapeutic care based mainly on surgery and optimal broad. It was metastatic in 9 patients, in whom treatment using imatinib as first-line in 4 of them with a good response in 3 patients and the possibility of R0 surgery in one patient, initial stabilization and then a secondary exhaust in a patient. The first surgery was necessary in 5 patients in complicated situation or if diagnostic doubt. The best characterization of GIST thanks to advances in cancer research has led to improved treatment of these tumors. Surgery is the standard treatment in localized forms. Imatinib is the standard treatment in metastatic GIST first line as well as adjuvant after surgery

[Internal mammary lymph node invasion in breast cancer: myth or reality]

The internal mammary nodes are often underestimated as breast cancer lymphatic pathway spread. It is yet the first site of lymphatic invasion in central or internal tumors and the second site in external tumors. The intra-thoracic situation of internal mammary nodes explains partly, the difficulty of its exploration. To evaluate the risk of internal mammary node invasion, some predictive factors are established [tumor size, internal or central tumor location, axillary node invasion and young age]. Prognostic and therapeutic impact of invasion justifies its systematic research. Without exploring internal mammary nodes status, TNM classification remains, incomplete. CT scanner, magnetic resonnance imaging, positron emission tomography scanner and sentinel node exploration technique are helpful to explore this region and to adapt its irradiation

[Central neurocytoma: a study of five cases]

Central neurocytoma is a very rare brain tumour recently described. The diagnosis rests on the data provided by anatomopathological examination and immunohistochemestry. We report a retrospective study of five cases of neurocytoma diagnosed in the Pathological laboratories of Anatomy and Cytology of Habib Bourguiba and Fattouma Bourguiba Hospitals over a period of two years [1999/2000]; this study was based on clinical, radiological and anatomopathological data. It was about three women and two men with an average age of 29 years [17 to 49 years] The tumor was located in the side ventricles in three cases. Two differential diagnoses were often discussed: oligodendroglioma and ependymoma. Immunohistochemistry showed an expression of the synaptophysine in every case. The treatment was exclusively surgical and the course was favorable with an average follow up of 48 months; only one case of relapse was noted of 36 months after the diagnosis

Hepatic and thoracic metastases from a meningeal haemangiopericytoma

Meningeal haemangiopericytomas are more aggressive than typical meningiomas, with a high rate of recurrence and distant metastasis. We report a case of recurrent meningeal haemangiopericytoma associated with hepatic and thoracic metastasis. Although local growth control of the meningeal tumour was obtained by tumor removal in a 33-year-old woman, the tumour was locally recurrent and metastasised extracranially within a period of 13 years. We emphasise the importance of complete removal at the first operation and subsequent radiation therapy to prolong the time to recurrence and extend survival