We reported a 35 year old breast cancer patient who was referred to our nuclear medicine department for sentinel node mapping. She was planned to undergo mastectomy and lymphatic mapping. A dose of Tc-99m Phytate was injection in the peri-areolar region in an intra-dermal fashion. Two hours post-injection no sentinel node was visible in the axilla. Due to a high liver uptake, inadvertent intra-vascular injection was suspected and another dose of the radiotracer was injected in the breast. Lymphoscintigraphy two minutes post-injection showed an axillary sentinel node. Our case underscores the importance of second radiotracer injection in case of sentinel node non-visualization.