A 19 years female abdominopelvic tumour appearing to arise from left ovary. CAI25 405. other markers normal. SURGICAL STAGING done. HP : POORLY DIFFERENTIATED ADENO CARCINOMA/ ALVEOLAR RHABDO MYOSARCOMA.

All other ovary normal. Advised IHC. Except WT1 all other negative. 3  months now patient is NED. What could be the diagnosis and management?