The patient is a 73 year old woman with a pigmented macule at the commisure of the lip for a number of years. The lesion measured 2 mm in diameter and it was excised with a 3 mm punch. She has Type II skin and has had BCC of her nose treated with Mohs surgery a number of years ago. She is in good general health.
Photos taken after suture removal.
Pathology: There is a confluent junctional proliferation of pleomorphic melanocytes
that exhibit pagetoid upward migration on a background of epidermal atrophy and solar elastosis.
These are the features of the lentigo maligna variant of melanoma in situ.
Diagnosis: Melanoma-in-situ, Lentigo maligna type
Question: This is an early lesion and surgical treatment may be overkill. What are your thoughts re: imiquimod, vs. Mohs (with MART-1), vs. watchful waiting?The rate of progression of LM to LMM is estimated to be ~ 3.5% per year. (Menzies SW, PMID 31095041 ) Does this information nudge one towards imiquimod over Mohs surgery?
