1 year old Rahul is brought with fever, fatigue, irritability, flushing, eating and bone pain. On examination a mass is palpable in the abdomen. What is he most likely suffering from?

Neuroblastoma is a malignancy arising from neural crest tissue of sympathetic ganglia or adrenal medulla. Flushing and sweating occur due to increased catecholamine secretion. Bone pain is due to metastasis. Reference: Current Diagnosis and Treatment: Paediatrics 20e chapter 29.