Serum tryptase levels in melanoma patients: case-control study and review of the literature.

BACKGROUND: Serum tryptase results from the constant release of the enzyme from mast cells and serum tryptase levels are commonly considered to be related to the total number of mast cells. They are increased in several malignancies, as pancreatic carcinoma, angiosarcoma, hepatic carcinoma and proliferative and/or non- proliferative hematological disorders. Contrariwise, it has been reported that the number of tryptase+ and chymase+ mast cells was lower in deeply invasive melanoma compared to in-situ melanoma and dysplastic nevi. Considering the underlying pathophysiological linkages between mast cells and melanocytes and that serum tryptase is related to angiogenesis, tissue-degrading proprieties and metastatization, we have decided to evaluate serum tryptase levels in melanoma patients and in a healthy control.

METHODS: We performed a case-control study evaluating serum tryptase in melanoma and in healthy group. Starting from an initial general analysis, we have performed a sub-analysis for each sample.

RESULTS: In general population serum tryptase was statistically higher in elderly patients. Generally, in melanoma patients, median serum tryptase was in lower normal range. We found a decreasing of serum tryptase levels from the healthy control to thin (≤ 1.00 mm Breslow thickness), reaching the lowest levels in thicker melanoma (≥ 1.01 m Breslow thickness), in ulcerated and metastatic melanoma.

CONCLUSION: Tryptase may have a protective role in melanoma or, conversely, it may play a role in the early stage of the tumorigenesis. Serum tryptase is an easy and useful biomarker to better investigate melanoma biology.