Previously Untreated Childhood Rhabdomyosarcoma
continued...
Extremity sites
The definitive surgical procedure involves wide local excision with en bloc removal of a cuff of normal tissue.[2] Complete tumor removal from the hand or foot is not feasible in most cases because of functional impairment.[17][Level of evidence: 3iiA] Primary re-excision may be appropriate in patients whose initial surgical procedure leaves microscopic residual disease that is resectable by a second procedure.[4]
Because of the significant incidence of nodal spread for extremity primary tumors (often without clinical evidence of involvement) and because of the prognostic and therapeutic implications of nodal involvement, extensive pretreatment assessment for regional nodal involvement is warranted.[18,19,20,21] The Children's Oncology Group Soft Tissue Sarcoma Committee (COG-STS) recommends systematic aggressive axillary node sampling for patients with upper-extremity primary tumors, even with clinically and radiographically negative nodes. The COG-STS also recommends inguinal and femoral triangle node sampling for patients with lower-extremity primary tumors, even with clinically and radiographically negative nodes. If clinically positive nodes are present, biopsy of more proximal nodes is recommended prior to sampling of the involved nodal region. Sentinel lymph node (SLN) mapping is employed at some centers to identify the regional nodes that are the most likely to be involved.[21,22,23,24] The contribution of SLN mapping is not yet clearly defined in pediatric patients.
Truncal sites
The surgical management of patients with lesions of the chest wall or abdominal wall should follow the same guidelines as those used for lesions of the extremities (i.e., wide local excision and an attempt to achieve negative microscopic margins). These resections may require use of prosthetic materials. Very large truncal masses should be biopsied initially. Chemotherapy, with or without RT, is then given. Initial surgery is performed if there is a realistic expectation of achieving negative margins. However, most patients who present with large tumors in these sites have localized disease that becomes amenable to complete resection with negative margins after preoperative therapy and is therefore associated with excellent long-term survival.[25,26,27,28]
Intrathoracic or intraabdominal sarcomas may not be resectable at diagnosis because of the massive size of the tumor and extension into vital organs or vessels.[29] For patients with initially unresectable retroperitoneal/pelvic tumors, complete surgical removal following chemotherapy, with or without RT, offers a significant survival advantage (73% vs. 34% to 44% without removal).[29]
With rhabdomyosarcoma of the biliary tree, total resection is rarely feasible. Outcome is good despite residual disease after surgery. External biliary drains significantly increase the risk of postoperative infectious complications. Thus, external biliary drainage is not warranted.[30]
Patients with rhabdomyosarcoma arising from tissue around the perineum or anus usually have advanced disease. These patients have a high likelihood of regional lymph node involvement, and about half of the tumors have alveolar histology. The current recommendation is to sample the lymph nodes. When feasible, without unacceptable morbidity, removing all gross tumor before chemotherapy is begun improves the likelihood of cure. In Intergroup Rhabdomyosarcoma Study Group (IRSG) Protocols I through IV, the overall survival (OS) after aggressive therapy for tumors in this location was 49%.[31]
WebMD Public Information from the National Cancer Institute
