A 56 year old woman presented with a history of a lump in the breast for 2 weeks. A fine needle aspiration confirmed the diagnosis of breast carcinoma for which she underwent modified radical mastectomy. She has a 3.5cm X 2 cm grade three infiltration duct carcinoma that was ER -ve, PR -ve and HER2 -ve. She had 5 positive axillary nodes with perinodal extension. She was initiated in chemotherapy with FEC (Epirubicin 100mg/mg/m2, Cyclophosphamide 500mg/m2 and 5-Fluorouracil 500mg/m2). She developed tongue pigmentation which increased with each cycle turning the entire tongue bleu-black after four cycles when this picture was taken.