A 76 yr old woman had a wide local excision and ipsilateral groin dissection for a moderately-differentiated squamous cell carcinoma of the right vulva. The tumour was 2.2 cm. maximal diameter and extended to within 2mm of the deep resection margin. All other margins were well clear of tumour. Metastatic carcinoma with extra capsular spread was identified in one of eleven lymph nodes that were removed.What would be your rationale and goals of treatment?