Prolonged skin staining after intradermal use of patent blue in sentinel lymph node biopsy for breast cancer

Aims To investigate the duration of staining of the skin after intradermal injection of patent blue during sentinel lymph node biopsy (SLNB) for breast cancer. Methods The clinical data of 33 consecutive patients who underwent a SLNB in combination with breast conserving therapy (BCT) in our hospital were retrospectively reviewed. Also, patients were interviewed at intervals of 3 months until the blue staining of their skin had disappeared. Results At mean follow-up of 18 months (range: 12–28) patent blue was visible at the site of injection after 3, 6, 9 and 12 months in 70, 64, 44 and 41% of the patients, respectively. Conclusions Use of the intradermal injection technique of patent blue during sentinel lymph node biopsy in BCT may result in remarkably long discolouring of the skin at the site of injection.