Generalized cutaneous granulocytic sarcoma with joint involvement.

Granulocytic sarcoma (GS) is a rare extra medullary solid tumour composed of immature myeloid cells. These tumours often display a greenish colour due to the enzymatic action of myeloperoxidase in the tumour cells. Hence, the term 'chloroma' was given to this lesion in 1853. GS commonly involves bone, periosteum, soft tissue, lymph node, and skin. Rare occurrences in muscle, meninges, breast, mediastinum, joints and ovary have been reported. Below-knee joint involvement in GS is unusual. We report a case of generalized cutaneous granulocytic sarcoma with ankle joint involvement who subsequently developed AML-M4.