Dilemmas associated with congenital ewing sarcoma family tumors

Ubiquitin-specific proteases as therapeutic targets in paediatric primary bone tumours?

In children and young adults, primary malignant bone tumours are mainly composed of osteosarcoma and Ewing's sarcoma. Despite advances in treatments, nearly 40% of patients succumb to these diseases. In particular, the clinical outcome of metastatic osteosarcoma or Ewing's sarcoma remains poor, with less than 30% of patients who develop metastases surviving five years after initial diagnosis. Over the last decade, the cancer research community has shown considerable interest in the processes of protein ubiquitination and deubiquitination. In particular, a growing number of studies show the relevance to target the ubiquitin-specific protease (USP) family in various cancers. This review provides an update on the current knowledge regarding the implication of these USPs in the progression of bone sarcoma: osteosarcoma and Ewing's sarcoma.

Extraskeletal Ewing's Sarcoma Masquerading as Infantile Benign Neck Mass

Despite being the second most common malignant bone tumor, Ewing's sarcoma remains uncommon in younger children and seldom seen in neonates and infants. Extraskeletal locations are even rarer, hardly ever suspected, and often misdiagnosed, causing delays in management. The histologic similarities of Ewing's sarcoma to more common pediatric small-blue-round-cell tumors such as lymphoma and neuroblastoma necessitate immunohistochemistry and molecular genetics for clinching the diagnosis. We report a soft-tissue Ewing's sarcoma in a 4-month-old female infant masquerading as a benign neck mass clinically, radiologically, cytologically, and intraoperatively. We also reviewed literature for any existing guidelines on when to biopsy neck masses in the pediatric population.

Congenital sacrococcygeal PNET and chemotherapy

We present the case of a congenital localised sacrococcygeal primitive neuroectodermal tumor treated aggressively with surgical resection and modified age-appropriate adjuvant chemotherapy. The conventional combination chemotherapy of vincristine, adriamycin, cyclophosphamide, ifosfamide and etoposide was modified to a regimen including vincristine, adriamicin, cyclophosphamide and actinomycin in order to minimise the predicted toxicity in this age group. Adjuvant “induction” chemotherapy commenced at 4 weeks of age and consisted of four cycles of vincristine, adriamycin and cyclophosphamide at 50%, 75%, 75% and 100% of recommended doses (vincristine 0.05 mg/kg, adriamycin 0.83 mg/kg daily × 2, cyclophosphamide 40 mg/kg) at 3-weekly intervals. This was followed by four cycles of “maintenance” chemotherapy with vincristine (0.025 mg/kg), actinomycin (0.025 mg/kg) and cyclophosphamide (36 mg/kg) at full recommended doses. Cardioxane at a dose of 16.6 mg/kg was infused immediately prior to the adriamycin. Our patient is thriving at 19 months out from end of treatment.

An unusual case of congenital primitive neuroectodermal tumor with ocular metastasis

Primitive neuroectodermal tumor (PNET) is most common in the second decade of life. Congenital PNET is very rare. Ocular metastasis of PNET is likewise exceedingly rare; with only 5 previously published cases. We report an unusual congenital PNET of the face, which metastasized to subcutis, eyes, and brain. The primary tumor responded to chemotherapy (vincristine/doxorubicin/cyclophosphamide) with metachronous progression of ocular lesions. A therapeutic trial of intraocular bevacizumab showed no efficacy on intraocular lesions. Eventually the patient developed cerebral metastasis, and second line therapy with topotecan/cyclophosphamide was initiated. The tumor progressed and the patient died after acute herniation.

Selective pathologies of the head and neck in children: a developmental perspective

The range of pathology seen in the head and neck region is truly amazing and to a large extent probably mirrors the complex signaling pathways and careful orchestration of events that occurs between the primordial germ layers during the development of this region. As is true in general for the entire discipline of pediatric pathology, the head and neck pathology within this age group is as diverse and different as its adult counterpart. Cases that come across the pediatric head and neck surgical pathology bench are more heavily weighted toward developmental and congenital lesions such as branchial cleft anomalies, thyroglossal duct cysts, ectopias, heterotopias, choristomas, and primitive tumors. Many congenital "benign" lesions can cause significant morbidity and even mortality if they compress the airway or other vital structures. Exciting investigations into the molecular embryology of craniofacial development have begun to shed light on the pathogenesis of craniofacial developmental lesions and syndromes. Much more investigation is needed, however, to intertwine aberrations in the molecular ontogeny and development of the head and neck regions to the represented pathology. This review will integrate traditional morphologic embryology with some of the recent advances in the molecular pathways of head and neck development followed by a discussion of a variety of developmental lesions finishing with tumors presumed to be derived from pluripotent/progenitor cells and tumors that show anomalous or aborted development.

Therapy and outcome of orbital primitive neuroectodermal tumor

Primary orbital primitive neuroectodermal tumor (PNET) is rare with no reported series. We report six cases of orbital PNET treated at a tertiary care oncology center in northern India from 2003 to 2008. None of them had distant metastases. All were treated with neoadjuvant chemotherapy followed by exenteration in two, radiotherapy and adjuvant chemotherapy in five cases. Three out of six achieved complete remission at end of therapy with globe salvage in three and vision in two cases. Chemoradiotherapy may help us to avoid mutilating surgery in large or locally advanced tumors, allowing preservation of vision or the globe.