[New in the current WHO classification (2020) for soft tissue sarcomas]

The current WHO classification for tumors of soft tissue and bone includes numerous new entities, most often defined by novel molecular findings. In this article, we present translocation-positive tumors to broaden the spectrum of monomorphic mesenchymal neoplasias. The undifferentiated small round cell sarcomas are now assembled in their own separate chapter to underline their occurrence in both soft tissue and bone, emphasizing their morphologic, molecular, and biologic differences. Another interesting new group are tumors with GLI1 activation, which, however, have not yet been included into the WHO classification. NTRK-driven tumors present with a potential therapeutic target for several established inhibitors. Finally, there have been novel findings in rhabdomyosarcomas allowing more precise subtyping associated with different biological behavior.

Rhabdomyosarcoma of the maxillofacial region in children and adolescents: Report of 9 cases and literature review

OBJECTIVE

To review clinical presentation, histology, treatment and survival for pediatric maxillofacial rhabdomyosarcoma (RMS) and evaluate the role of surgical treatment.

STUDY DESIGN

Retrospective analysis of medical charts.

METHODS

Files of patients, treated for primary maxillofacial RMS from 1997 to 2016, were examined for clinical presentation, staging, histology, treatment protocol and complications, recurrence and final outcome.

RESULTS

Our cohort included 4 male and 5 female patients (mean age 8.47 years). One tumor, occupying the infratemporal space, was parameningeal; the other 8, located at the mandible (4) or the maxilla/zygomatic bone (4) were non-parameningeal. All patients received chemotherapy preoperatively. Surgery was performed in 7 patients, of whom 4 received postoperative radiotherapy. The histological type was alveolar (5) or embryonal (4). Overall survival hitherto was 66,6%, depending on histology (40% and 100% for the alveolar and embryonal type respectively).

CONCLUSIONS

Pediatric maxillofacial RMS originated mostly from the facial skeleton and most tumors were non-parameningeal. The alveolar type was slightly more common. An individualized multidisciplinary approach combining chemotherapy and local control mostly with surgery and selectively with radiotherapy has proven successful for the treatment of non-orbital, non-parameningeal maxillofacial RMS. Histology was a major treatment determinant and the most important prognostic factor.