DISCUSSION
This case illustrates the phenomenon—known as regression—in which part or all of a cutaneous melanoma is rendered invisible over time by the reaction of the immune system (although not before it has a chance to spread). Not uncommonly, these patients are diagnosed with metastatic melanoma and no primary lesion is ever discovered.
A variation on this theme is the so-called amelanotic melanoma, which can present initially in a wide variety of forms—papules, nodules, or macules; in shades of pink, blue, white, or "flesh." But unlike our patient, these cases do not involve regression.
This patient and his wife assumed that because the primary lesion had essentially disappeared, it must have been safe. And of course, they failed to connect it with the new axillary nodule.
At this writing, the extent of the patient’s disease remains to be defined by imaging studies (PET and CT scans). But given the facts of the case, his prognosis at best is guarded. A more hopeful view is that he is living in a time of meaningful discovery of better treatments for advanced melanomas.
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