Treatment of Melanoma Excision Wound With 50% Zinc Chloride Solution Astringent-Mohs Melanoma Surgery Without the...

BACKGROUND: Dr. Frederic Mohs believed that surgery can spread a melanoma; to prevent this, he applied an inactive black paste vehicle containing the active ingredient 50% zinc chloride solution to melanomas to kill and fix (i.e., preserve) tissue; this is termed fixed-tissue surgery. A statistically significant, 53-percent, five-year melanoma survival improvement in 103 consecutive cases was reported for fixed-tissue surgery compared to five-year survival for cases treated with conventional surgery (p=0.003). Nine physicians, including the author, contributed to a melanoma registry of 179 cases between 1981 and 1991, and in 64 five-year determinate cases of thin melanomas (<0.85mm), survival was improved by 60 percent with zinc chloride paste simply applied after excision to the open fresh-tissue wound compared to conventional surgery (95.7% five-year survival with zinc chloride applied to the excision wound vs. 88.9% five-year survival with conventional fresh-tissue excision only, hazard ratio 0.37). When applied to an open fresh excision wound in either a solution or paste form, zinc chloride penetrates instantly; the author has found both forms to be equally effective. In solution form, the application technique is simple and similar to the astringent 20% aluminum chloride solution applied with sterile gauze or Q-tip, but the inactive paste vehicle requires special dressings. Additionally, the inactive paste used by Mohs contains stibnite antimony; therefore, it cannot be formulated to USP standards and is not recognized by the FDA as a generally safe substance. However, zinc chloride is recognized by the FDA as a generally safe substance, and the 50% solution can be formulated by a compounding pharmacist to USP standards. 50% zinc chloride solution penetrates deeply and kills tissue and should not be used without previous biopsy confirmation of melanoma or melanoma in situ. The killing of tissue on the melanoma excision wound by the zinc chloride causes the wound to become deeper and wider, and therefore a smaller and thinner excision margin can be removed.