A rare cause of Sister Mary Joseph's nodule.

Sister Mary Joseph's nodule is an important physical sign. It usually represents umbilical metastasis of intra abdominal malignancy. Its association with intra abdominal desmoplastic small round cell tumour is extremely rare. We describe a rare case of sister Mary Joseph's nodule associated with desmoplastic small round cell tumour. We conclude that differential diagnosis of Sister Mary Joseph's nodule should include desmoplastic small round cell tumour, especially in adolescents and young adults.