The above picture gives mnemonic for Ewing's tumor. First let us analyse the picture. Note the chick and swelling of Diaphysis of Tibia with the onion. Chick says VAC VAC VAC VACA, VAC VAC VAC AV / CV. The chick has fat and hence PAS stain positive. Note the moon and star at the top, Radio streaming music and chick fluttering it's wings up and down to the music as represented by 2 arrow marks at the left side. See the melted snow below the bone and a blood vessel from the side ( left corner )
Now, this is what the picture says: Ewings - the chick with wings; Arises from Diaphysis, most common bone is Tibia. Seen in children as represented by the chick. Onion represents the onion peel appearance in X-rays. The wings going up and down ( arrows ) represent that the size of tumor increases and decreases ( H/O Exacerbations and remissions ). The moon & star represents the clinical feature that pain is worse at night. Radio represents that the tumor is extremely radiosensitive - therefore melts like snow. Spread is by blood vessels and lymphatics. And what the chick says is the chemotherapy regimen - VAC ( Vincristine, Adriamycin, Cyclophosphamide ), VACA ( VAC + Actinomycin ), AV alternating with CV.
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