Diagnosis of malignant melanoma is by biopsy. A doctor should be consulted if there are any suspicious skin markings. The appearance of the growth, sore, or lump are to be examined.
A small area of a growth or the entire growth is removed and the specimen is analysed by a pathologist.
A non-invasive technique called surface microscopy (dermoscopy, and epiluminescence microscopy) is sometimes employed for early diagnosis. But biopsy remains the gold standard.
Spread of the cancer is accessed by tests like sentinel lymph node (SLN) biopsy, CT scans and other imaging modalities.