Diagnosis and Treatment of Nasopharyngeal Carcinoma in Children and Adolescents - Recommendations of the GPOH-NPC Study Group

Nasopharyngeal carcinoma (NPC) is a rare malignant tumor arising from epithelial cells of the nasopharynx. Its incidence is highest in Southeast Asia. Age distribution of NPC is bimodal, with one peak in young adolescents and another in patients 55-59 years of age. EBV appears to be the primary etiologic agent in the pathogenesis, environmental factors such as nitrosamines and genetic factors are contributory. NPC is most commonly diagnosed in locally advanced stages, with lymph node metastases occurring in up to 90 % of patients. About 5-10 % of patients present with distant metastases. Diagnosis of NPC is made histologically, supported by an abnormal anti-EBV-VCA IgA titer and elevated plasma EBV-DNA load. Superior results in children and adolescents with advanced locoregional NPC, with overall and event-free survival rates >90 %, have been achieved by neoadjuvant chemotherapy with 5-fluoruracil and cisplatin, followed by synchronous radiochemotherapy and subsequent maintenance therapy with interferon-beta as demonstrated by the 2 prospective studies GPOH-NPC-91 and -2003. Response to therapy can be assessed by PET-imaging and in patients with complete remission after neoadjuvant chemotherapy, the radiation dose to the primary tumor can be safely reduced from 59.4 to 54.4 Gy. Since the majority of long term sequalae such as xerostomia, skin and tissue fibrosis are caused by high radiation dosages, radiotherapy modalities such as intensity-modulated radiotherapy should be used to efficiently spare non-tumorous tissue. For patients with metastatic disease and relapse, survival chances are low. New treatment strategies, such as the application of EBV-specific T-lymphocytes should be considered for these patients

Multifocal gastric gastrointestinal stromal tumors (GISTs) with lymph node metastases in children and young adults: A comparative clinical and histomorphological study of three cases including a new case of Carney triad

<p>Abstract</p> <p>Background</p> <p>Gastrointestinal stromal tumors (GISTs) are the most frequent mesenchymal tumors of the gastrointestinal tract usually occurring in the 6^thto 7^thdecade of life, while their occurrence in children is rare (1-2%).</p> <p>Carney triad (CT), a non-hereditary association of gastric GIST with pulmonary chondroma and/or extraadrenal paraganglioma, is an even much rarer disease (to date ~120 cases reported worldwide) usually affecting young adult females. Pediatric GISTs differ from CT-associated GISTs solely by the absence of other components of the triad and are completely different from sporadic GISTs of the adult. Both, pediatric and CT-GISTs, metastasize frequently to regional lymph nodes (29%) and are usually wild type (WT) for common KIT-/PDGFRA mutations.</p> <p>Case presentation and results</p> <p>We compare one new CT GIST with two pediatric/young adult multifocal gastric GISTs presenting with lymph node metastases. We put special focus on histomorphological growth pattern in the primary tumors and in the metastases.</p> <p>The two cases of pediatric/young adult GIST without the other components of CT showed all the features of the triad: female gender, young age, multifocal antral-based gastric GIST with biphasic histological growth pattern, lymph node metastases, hypercellularity and WT status for common KIT-, PDGFRA- and B-RAF mutations.</p> <p>Discussion and conclusion</p> <p>Pediatric/CT-associated GISTs and sporadic GISTs of the adults differ significantly from each other with regard to patients' age, gender, tumor localisation, histomorphological growth pattern, mutational status and risk for metastasis. Our cases of pediatric/young adult GISTs show all characteristics of CT except for the absence of other components of the triad.</p> <p>Therefore these GISTs are probably not sporadic, but may represent either early manifestation or <it>forme fruste </it>of the CT. Thus, these patients need to be regularly examined for the development of extraadrenal paraganglioma or pulmonary chondroma.</p

Genome-wide association study identifies multiple new loci associated with Ewing sarcoma susceptibility.

Ewing sarcoma (EWS) is a pediatric cancer characterized by the EWSR1-FLI1 fusion. We performed a genome-wide association study of 733 EWS cases and 1346 unaffected individuals of European ancestry. Our study replicates previously reported susceptibility loci at 1p36.22, 10q21.3 and 15q15.1, and identifies new loci at 6p25.1, 20p11.22 and 20p11.23. Effect estimates exhibit odds ratios in excess of 1.7, which is high for cancer GWAS, and striking in light of the rarity of EWS cases in familial cancer syndromes. Expression quantitative trait locus (eQTL) analyses identify candidate genes at 6p25.1 (RREB1) and 20p11.23 (KIZ). The 20p11.22 locus is near NKX2-2, a highly overexpressed gene in EWS. Interestingly, most loci reside near GGAA repeat sequences and may disrupt binding of the EWSR1-FLI1 fusion protein. The high locus to case discovery ratio from 733 EWS cases suggests a genetic architecture in which moderate risk SNPs constitute a significant fraction of risk