What is the use of injecting Methylene Blue dye in a Breast cancer surgery?

Ans. (c) Sentinel lymph node biopsy(Ref. Sabiston 20th ed; pg. 849-850.)SENTINEL LYMPH NODE BIOPSY* Now done in Stage I patients with clinically node negative patients as a part of Nodal staging to prevent morbidity due to unnecessary axillary surgery* Technique of injecting methylene or isosulfan blue dye peritumorally and locating the blue node (suspected sentinel node - first node to be drained by the tumor) and doing excision biopsy with frozen section to rule out malignant deposits.* For better accuracy, lymphoscintigraphy can aid.2.5mCiTc99m sulphur colloid 1 day prior to surgery +Peritumoral injection of 3-5ml isosulfan blue dye inside OT|Gamma probe to locate the hot spot||* Hot spot picked up* Incision and locate the blue node and excise it* Check for Radioactivity in bed* No hot spot* Excise primary which might decrease background* Radioactivity shine||* Activity is Present* Further nodes resected until residual radioactivity <10% of the 10 sec ex vivo count of most radioactive SLN* No activity* Send for Frozen ||Positive - Do Standard ALNC Negative - Close the Wound * IDEAL - 2 - 3 sentinel nodes per patient to be dissected