Improved 6-year overall survival in AT/RT - results of the registry study Rhabdoid 2007.

Atypical teratoid rhabdoid tumors (AT/RT) are characterized by mutations and subsequent inactivation of SMARCB1 (INI1, hSNF5), a predilection for very young children and an unfavorable outcome. The European Registry for rhabdoid tumors (EU-RHAB) was established to generate a common European database and to establish a standardized treatment regimen as the basis for phase I/II trials. Thus, genetic analyses, neuropathologic and radiologic diagnoses, and a consensus treatment regimen were prospectively evaluated. From 2005 to 2009, 31 patients with AT/RT from four countries were recruited into the registry study Rhabdoid 2007 and treated with systemic and intraventricular chemotherapy. Eight patients received high-dose chemotherapy, 23 radiotherapy, and 17 maintenance therapy. Reference evaluations were performed in 64% (genetic analyses, FISH, MLPA, sequencing) up to 97% (neuropathology, INI1 stain). Germ-line mutations (GLM) were detected in 6/21 patients. Prolonged overall survival was associated with age above 3 years, radiotherapy and achievement of a complete remission. 6-year overall and event-free survival rates were 46% (±0.10) and 45% (±0.09), respectively. Serious adverse events and one treatment-related death due to insufficiency of a ventriculo peritoneal shunt (VP-shunt) and consecutive herniation were noted. Acquisition of standardized data including reference diagnosis and a standard treatment schedule improved data quality along with a survival benefit. Treatment was feasible with significant but manageable toxicity. Although our analysis is biased due to heterogeneous adherence to therapy, EU-RHAB provides the best available basis for phase I/II clinical trials.

Detection of SMARCB1 loss in ascites cells in the diagnosis of an abdominal rhabdoid tumor.

We report on how MLPA and Sequencing of SMARCB1/INI1/SNF5 might be applied for initial diagnosis of rhabdoid tumor patients. These techniques were successfully used to detect loss of SMARCB1 in tumor cells of the ascites in a 3-month-old patient in which tumor biopsy could not initially be made due to life threatening intraabdominal bleedings.

Synchronous congenital malignant rhabdoid tumor of the orbit and atypical teratoid/rhabdoid tumor--feasibility and efficacy of multimodal therapy in a long-term survivor.

Among infant malignancies, congenital tumors, especially those of the central nervous system (CNS), constitute a rather unique subgroup. Poor survival rates (28% in CNS tumors) may be attributed to the aggressive biology as well as specific therapeutic limitations innate to the young age of affected patients. Our patient developed synchronous congenital tumors: an atypical teratoid/rhabdoid tumor (AT/RT) localized in the right lateral ventricle of the brain and a malignant rhabdoid tumor (MRT) in the soft tissue of the right orbit. A de novo germline chromosomal deletion in 22q encompassing the SMARCB1 gene was detected, prompting the diagnosis of a de novo rhabdoid tumor predisposition syndrome 1 (RTPS1). The patient was reported to the European Rhabdoid Registry (EU-RHAB) and treated according to the Rhabdoid 2007 recommendation. Despite the very young age of the patient, the initially desperate situation of RTPS1, and the synchronous localization of congenital rhabdoid tumors, intensive chemotherapy was well tolerated; the child is still in complete remission 5 years following diagnosis. In conclusion, RTPS1 with congenital synchronous MRTs is not necessarily associated with a detrimental outcome. Intensive multidrug chemotherapy, including high dose chemotherapy, may be feasible and justified.

Identification of genes involved in the biology of atypical teratoid/rhabdoid tumours using Drosophila melanogaster.

Atypical teratoid/rhabdoid tumours (AT/RT) are malignant brain tumours. Unlike most other human brain tumours, AT/RT are characterized by inactivation of one single gene, SMARCB1. SMARCB1 is a member of the evolutionarily conserved SWI/SNF chromatin remodelling complex, which has an important role in the control of cell differentiation and proliferation. Little is known, however, about the pathways involved in the oncogenic effects of SMARCB1 inactivation, which might also represent targets for treatment. Here we report a comprehensive genetic screen in the fruit fly that revealed several genes not yet associated with loss of snr1, the Drosophila homologue of SMARCB1. We confirm the functional role of identified genes (including merlin, kibra and expanded, known to regulate hippo signalling pathway activity) in human rhabdoid tumour cell lines and AT/RT tumour samples. These results demonstrate that fly models can be employed for the identification of clinically relevant pathways in human cancer.

Clinical and genetic features of rhabdoid tumors of the heart registered with the European Rhabdoid Registry (EU-RHAB).

Rhabdoid tumors are rare but highly aggressive malignancies of infancy and early childhood with a generally unfavorable prognosis. Despite a wide variety of anatomic locations rhabdoid tumors share mutational inactivation of the SWI/SNF (SWItch/Sucrose NonFermentable) core component gene SMARCB1 (also known as INI1, hSNF5 or BAF47) in chromosome 22. As this inactivation usually results in loss of SMARCB1 expression, detectable by an antibody against the SMARCB1 protein, the accurate diagnosis of a rhabdoid tumor may be more distinctly and frequently made. Several reports on rhabdoid tumors presenting in various anatomic sites outside the kidneys and CNS are on record. We report two cases of rhabdoid tumors originating in the heart (cardiac tissue), which were entered into the European Rhabdoid Registry (EU-RHAB). The first case presented with intracardial and -cranial lesions as well as malignant ascites, while the second patient demonstrated an isolated cardiac tumor. This induced a different therapeutic approach and subsequently different clinical course (death 7 weeks after diagnosis in patient 1). Patient 2 presented with a bifocal intracardial tumor without metastases and remains in complete remission for 46 months since diagnosis following multimodal therapy. The second case demonstrates that even in a potentially futile clinical situation early and accurate diagnosis followed by prompt and intensive multimodal therapy may offer prolonged survival, potential cure and improved quality of life.

Arsenic trioxide inhibits tumor cell growth in malignant rhabdoid tumors in vitro and in vivo by targeting overexpressed Gli1.

Rhabdoid tumors are highly aggressive tumors occurring in infants and very young children. Despite multimodal and intensive therapy prognosis remains poor. Molecular analyses have uncovered several deregulated pathways, among them the CDK4/6-Rb-, the WNT- and the Sonic hedgehog (SHH) pathways. The SHH pathway is activated in rhabdoid tumors by GLI1 overexpression. Here, we demonstrate that arsenic trioxide (ATO) inhibits tumor cell growth of malignant rhabdoid tumors in vitro and in a mouse xenograft model by suppressing Gli1. Our data uncover ATO as a promising therapeutic approach to improve prognosis for rhabdoid tumor patients.

Favorable outcome of patients affected by rhabdoid tumors due to rhabdoid tumor predisposition syndrome (RTPS).

Rhabdoid tumor predisposition syndrome is usually associated with shorter survival in patients with malignant rhabdoid tumors regardless of anatomical origin. Here we present four children harboring truncating heterozygous SMARCB1/INI1 germline mutations with favorable outcome. All four patients received multi-modality treatment, three according to therapeutic recommendations by the EU-RHAB registry, two without radiotherapy, and mean event-free survival accounts for 7 years. In conclusion, intensive treatment with curative intent is justified for children with rhabdoid tumors even if an underlying rhabdoid predisposition syndrome is demonstrated.

High-resolution genomic analysis suggests the absence of recurrent genomic alterations other than SMARCB1 aberrations in atypical teratoid/rhabdoid tumors.

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare malignant pediatric brain tumor characterized by genetic alterations affecting the SMARCB1 (hSNF5/INI1) locus in chromosome band 22q11.2. To identify potential additional genetic alterations, high-resolution genome-wide analysis was performed using a molecular inversion probe single-nucleotide polymorphism (MIP SNP) assay (Affymetrix OncoScan formalin-fixed paraffin-embedded express) on DNA isolated from 18 formalin-fixed paraffin-embedded archival samples. Alterations affecting the SMARCB1 locus could be demonstrated by MIP SNP in 15 out of 16 evaluable cases (94%). These comprised five tumors with homozygous deletions, six tumors with heterozygous deletions, and four tumors with copy number neutral loss of heterozygosity (LOH) involving chromosome band 22q11.2. Remarkably, MIB SNP analysis did not yield any further recurrent chromosomal gains, losses, or copy neutral LOH. On MIP SNP screening for somatic mutations, the presence of a SMARCB1 mutation (c.472C>T p.R158X) was confirmed, but no recurrent mutations of other cancer relevant genes could be identified. Results of fluorescence in situ hybridization, multiplex ligation-dependent probe amplification, and SMARCB1 sequencing were highly congruent with that of the MIP SNP assay. In conclusion, these data further suggest the absence of recurrent genomic alterations other than SMARCB1 in AT/RT.

Nine months to progression using fourth-line liposomally encapsulated paclitaxel against hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is the third most common cause of cancer deaths. Difficulties to diagnose HCC at early stages remain the major obstacle to curative (surgical) therapy. Therapy in advanced stages has to be considered palliative. In this situation, a considerable amount of attention should be paid to innovative treatment strategies, e.g. including antiangiogenetic drugs. RESULTS: We report on the successful treatment of a patient suffering from progressive HCC with a novel drug (EndoTAG-1, formerly named LipoPac) currently investigated in phase II studies. This drug consists of liposomally encapsulated paclitaxel. Its liposomal formulation favors the drug's adherence to the tumor neovasculature, in effect starving the tumor. CONCLUSIONS: EndoTAG-1 stopped tumor progression for 9 months in our patient. This, along with successes observed testing this drug against other indications, makes it a suitable candidate for future clinical trials.