Current management of pediatric soft tissue sarcomas

Abstract

Pediatric soft tissue sarcomas are a group of malignant neoplasms arising within embryonic mesenchymal tissues during the process of differentiation into muscle, fascia and fat. The tumors have a biphasic peak for age of incidence. Rhabdomyosarcoma (RMS) is diagnosed more frequently in younger children, whereas adult-type non-RMS soft tissue sarcoma is predominately observed in adolescents. The latter group comprises a variety of rare tumors for which diagnosis can be difficult and typically requires special studies, including immunohistochemistry and molecular genetic analysis. Current management for the majority of pediatric sarcomas is based on the data from large multi-institutional trials, which has led to great improvements in outcomes over recent decades. Although surgery remains the mainstay of treatment, the curative aim cannot be achieved without adjuvant treatment. Pre-treatment staging and risk classification are of prime importance in selecting an effective treatment protocol. Tumor resectability, the response to induction chemotherapy, and radiation generally determine the risk-group, and these factors are functions of tumor site, size and biology. Surgery provides the best choice of local control of small resectable tumors in a favorable site. Radiation therapy is added when surgery leaves residual disease or there is evidence of regional spread. Chemotherapy aims to reduce the risk of relapse and improve overall survival. In addition, upfront chemotherapy reduces the aggressiveness of the required surgery and helps preserve organ function in a number of cases. Long-term survival in low-risk sarcomas is feasible, and the intensity of treatment can be reduced. In high-risk sarcoma, current research is allowing more effective disease control.

Keywords: Pediatric tumor; Rhabdomyosarcoma; Soft tissue sarcoma; Non-rhabdomyosarcoma pediatric soft tissue tumor

Core tip: The manuscript describes current management of pediatric soft tissue sarcomas, a large group of rare tumors in pediatric age group. The group has two main categories; rhabdomyosarcoma (RMS) and non-RMS pediatric soft tissue tumors. Treatment of these tumors is in multidisciplinary fashion comprising of surgery, chemotherapy and radiation therapy. Decision making in management protocol for each patient is based on the risk determined by various clinical and pathological parameters. For cases with low-risk, surgical removal is usually adequate when adjuvant chemoradiation are proven helpful in cases with significant risk of recurrence. The overall survival in these tumors has become brighter in the recent decades.