Urine melanin is a test to determine the abnormal presence of melanin in the urine.
Thormahlen's test; Melanin - urine
How the Test is Performed
A clean-catch urine sample is needed.
How to Prepare for the Test
No special preparation is needed.
How the Test Will Feel
The test involves only normal urination.
Why the Test is Performed
This test is used to diagnose melanoma, a type of skin cancer that produces melanin. If the cancer spreads (especially within the liver), the cancer may produce enough of this substance that it shows up in the urine.
Normally, melanin is not present in urine.
What Abnormal Results Mean
If melanin is present in the urine, malignant melanoma is suspected.
There are no risks associated with this test.
This test is rarely performed as there are better diagnostic tests available.
Reviewed By: Frank A. Greco, M.D., Ph.D., Director, Biophysical Laboratory, The Lahey Clinic, Burlington, MA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.