A prospective trial comparing 1% lymphazurin vs 1% methylene blue in sentinel lymph node mapping of gastrointestinal tumors.

BACKGROUND

Methylene blue (M), as a dye in sentinel lymph node mapping (SLNM), has been introduced as an alternative to lymphazurin (L) after the recent shortage of L. M has been evaluated in breast cancer in multiple studies with favorable results. Our study compares L with M in the SLNM of gastrointestinal (GI) tumors.

METHODS

Between Jan 2005 and Aug 2008, 122 consecutive patients with GI tumors were enrolled. All patients (pts) underwent SLNM with either L or M by subserosal injection of 2-5 mL of dye. Efficacy and rates of adverse reactions were compared between the two dyes. Patients were prospectively monitored for adverse reactions including anaphylaxis, development of blue hives, and tissue necrosis.

RESULTS

Of 122 pts, 60 (49.2%) underwent SLNM using L and 62 (50.8%) underwent SLNM using M. Colon cancer (CrCa) was the most common site in both groups. The success rate of L and M in SLNM was 96.6% and 96.7%, respectively, with similar numbers of total number of lymph nodes per pt, SLNs per pt (<3), nodal positivity, skip metastasis, and accuracy. The only adverse reaction in the L group was oxygen desaturation >5% in 5% (3/60) of pts, compared with none in the M group. Cost per vial of L was $210 vs $7 for M.

CONCLUSION

The success rate, nodal positivity, average SLNs per patient, and overall accuracy were similar between L and M. Absence of anaphylaxis and lower cost make M more desirable than L in SLNM of GI tumors.