High Risk

The goal of surgery in high-risk tumors is an initial diagnostic biopsy to obtain an adequate amount of tissue for biologic studies (1 cm3; see the present chapter). Complete resection of the primary tumor is usually done after neoadjuvant chemotherapy and is the current COG recommendation. Following chemotherapy, imaging studies (computerized tomography or magnetic resonance imaging) are obtained prior to surgery and post-operatively to assess the extent of resection. Some studies suggest that the completeness of resection will have a major impact on local recurrence and ultimate survival (La Quaglia et al. 1994, 2004; Tokiwa et al. 2003). These operations are typically difficult even in the best of hands, and require careful presurgical planning and consultation among colleagues with appropriate expertise. In patients with progressive disease, surgery is generally not recommended.

11.4.4.3.1 Gross Total Resection

Neuroblastomas are infiltrative tumors that usually involve the retroperitoneum or mediastinum. Except for small adrenal primaries, none can be resected with a negative microscopic margin as is done with epithelial tumors and some sarcomas; however, in some cases all grossly visible and palpable disease in the primary site and regional lymphatics can be removed leading to the term "gross total resection." The microscopic margin is always assumed to be positive. It is noteworthy that all high-risk patients are also treated with radiation therapy. There are no studies that dissect the individual role of radiation vs surgery in the local control of neuroblastoma; however, radiation therapy alone is generally unable to induce a complete remission in soft tissue sites of gross tumor involvement in advanced-stage neu-roblastoma. In general, patients receive both modalities and any analysis should account for this colin-earity.

11.4.4.3.2 Rationale for Gross Total Resection in High-Risk Patients

High-risk patients often have extensive primary tumors as well as large metastatic deposits in regional lymph nodes and/or in bone and bone marrow. In view of this, many pediatric surgeons have rightly questioned the efficacy and safety of primary tumor resection and regional lymphadenectomy. Table 11.4.1 lists reports that refer to the role of surgery in neuroblastoma, including patients with high-risk disease. None of these reports are prospective and only a few define resection by criteria other than the operative report. Overall, the majority of studies support a role for gross total resection in the treatment of high-risk neuroblastoma. Most authors have ana

Table 11.4.2 Local control

Reference

Number

Local progression or recurrence with in complete resection (%)

Probability of primary site relapse with gross total resection (%)

0 0

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