Soft tissue sarcomas account for a small proportion of second cancers, with an estimated frequency of < 10%. The most common histologic type of soft tissue sarcomas as second cancers include mostly high-grade sarcomas, such as rhabdomyosarcoma, malignant peripheral nerve sheath tumour, fibrosarcoma, leiomyosarcoma, synovial sarcoma, alveolar soft part sarcoma and Ewing sarcoma/primitive neuroectodermal tumour (PNET). We report a case of superficial soft tissue Ewing sarcoma/PNET as a second cancer in a young patient previously treated for Hodgkin's disease (HD). To the best of our knowledge and based on a literature search, this is the first reported case of post-irradiation soft tissue Ewing sarcoma/PNET as a second cancer arising in the same area irradiated for cure of HD.