<s>[INST] context: Neuroblastoma is a cancer often found in the small glands on top of the kidneys (adrenal glands). It can develop in the stomach, chest, neck, pelvis and bones. Children aged five or younger are most commonly affected. Most children with neuroblastoma in Noh America have been treated according to the In the previous COG risk system, each child was assigned to a low-risk, intermediate-risk, or high-risk group (refer to Tables INSS stage. Age. International Neuroblastoma Pathologic Classification (INPC). Ploidy. Amplification of the MYCN oncogene within tumor tissue.[Other biological factors that influenced treatment selection in previous COG studies included unbalanced 11q loss of heterozygosity and loss of heterozygosity for chromosome 1p.[Generally, treatment is based on whether the tumor is classified as low, intermediate, or high risk, as follows: Low risk. For patients with low-risk tumors, the approach is either observation or resection, with chemotherapy restricted to symptomatic patients with low-risk biology. Five-year overall survival (OS) was 97% in a large COG study.[Intermediate risk. For patients with intermediate-risk tumors, chemotherapy is often given before definitive resection, and the number of chemotherapy cycles is based on clinical and tumor biological risk factors and response to therapy. In recent studies, select patients have been observed without undergoing chemotherapy or attempted resection. The 3-year OS rate for intermediate-risk patients was about 96% in a large COG study.[High risk. For high-risk patients, treatment has intensified to include chemotherapy, surgery, radiation therapy, myeloablative therapy and stem cell transplant (SCT), isotretinoin, and immunotherapy, resulting in survival rates of about 50%. Statistically significant improvement in survival was observed in a randomized phase III COG study ( COG Risk-Group Assignment Treatment Options COG = Children's Oncology Group; GM-CSF = granulocyte-macrophage colony-stimulating factor; 131I-MIBG = iodine I 131-metaiodobenzylguanidine; SCT = stem cell transplant. Recurrent Neuroblastoma Locoregional recurrence in patients initially classified as low risk Metastatic recurrence in patients initially classified as low risk Locoregional recurrence in patients initially classified as intermediate risk Metastatic recurrence in patients initially classified as intermediate risk Recurrence in patients initially classified as high risk Recurrence in the central nervous system <a style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font: inherit; veical-align: baseline; color: ; text-decoration-line: none;" href=" therapeutic approaches</a>. Refer robbins 8/e p477 [/INST] question: Spontaneous regression though rare is seen in | options: A: Burkits lymphoma B: Wilms tumor C: Neuroblastoma D: Melanoma | answer: C </s>