Sentinel biopsy is most effective in :

Restricting unnecessary lymph node dissection reduces the surgical morbidity in early vulval cancer. Lymphatic mapping and sentinel node biopsy (frozen section) before or during surgery help in carrying out adequate surgical procedure with good prognosis. Mapping is done by: Intraoperative intradermal injection of blue dye around the tumour. A detection rate of 100% is repoed. Labelling tissues with radioactive tracer and localization with a hand-held detector. Lymphoscintigraphy has also 100% detection rate. Reference: Shaw's Textbook of Gynaecology 16th edition page no 479