Path Report and questions: Lentigo Maligna Melanoma

History of this newly diagnosed melanoma:
During full body scan August, 2019. Derm noted unusual pink spot on right forearm, took a photo of it, and said if it’s not a “bug bite” and doesn’t heal up we’ll watch it.
I kept an eye on it all winter: flat, pink, a little patchy, not huge.

Fast forward to March, 2020: Over four weeks it seemed to become pinker, raised now (puffy with a palpable lump), with a distinct and tiny “bug bite” hole at the top of it. Went in last week, derm said it didn’t seem to have changed much, but would do a shave biopsy cause she would be really surprised now if it wasn’t a BCC or SCC. I said, what if it’s a melanoma? Would a shave then not be indicated? She said due to COVID19 situation, and of not wanting me to chance virus exposure coming in for a second treatment visit next week, and because she would bet her life on it being a BCC or SCC she’d go ahead with a shave and then an ED and C (electrodessication and cutterage) to finish it off so I wouldn’t have to come back in again. Of course, I said OK (I have seen this derm for 25 years and she’s never steered me wrong).
Pathology report:
Clinical Data: A: Morphology: erythematous indurated plaque
Diagnosis: Rt Prox Dorsal Forearm MELANOMA, BRESLOW’S MAXIMUM THICKNESS 0.2MM, TRANSECTED BY A PERIPHERAL EDGE.

SYNOPTIC REPORT
PROCEDURE: BIOPSY, SHAVE
SPECIMEN LATERALITY AND TUMOR SITE: RIGHT PROXIMAL DORSAL FOREARM
GROSS TUMOR SIZE: NOT INDICATED
HISTOLOGIC TYPE: LENTIGO MALIGNA
BRESLOW’S DEPTH: 0.2MM
ULCERATION: PRESENT, BUT LIKELY TRAUMATIC
CLARK’S LEVEL: II
MITOITC RATE: 0/mm SQUARED
MICROSATELLITOSIS: INDETERMINATE
LYPHOVASCULAR INVASION: NOT IDENTIFIED
TUMOR INFILTRATING LYMPHOCYTES: PRESENT, NON-BRISK
REGRESSION: NOT IDENTIFIED
PRECURSOR LESION: NOT IDENTIFIED
PERIPHERAL AND DEEP MARGINS: PERIPHERAL MARGINS INVOLVED, DEEP MARGIN UNIVOLVED
STAGE: pT1a

Multiple levels reveal an elongated specimen which is focally ulcerated and covered by fibrinopurulent crust, associated with dermal collagen degeneration. There is a broad and irregular proliferation of hyperchromatic and pleomorphic melanocytes in a confluent pattern along the junction focally within the papillary dermis at a thickness of 0.2,,. There is severe solar elastosis. There is a patchy lymphohistiocytis infiltrate.

Questions for anyone who can speak to this: Lentigo maligna melanoma is a pretty rare subtype that usually arises from a brown, spreading patch. Mine was small, and pink and did not present typically, hence my dermatologist’s shock when she had to call me with the news.

1) Anyone out there with a lentigo maligna melanoma that presented atypically? If so, what was your experience?

1a) Also curious about “Desmoplasic Melanoma” and its association with Lentigo Maligna Melanoma, if you have any experience (as that is an amelanotic presentation…my pink lesion? that has gone undiagnosed???)

2) What does ULCERATION PRESENT, BUT LIKELY TRAUMATIC mean in the scheme of things?

3) Was this able to be staged because the pathologist was able to read the deep margin, even though it was a shave biopsy?

4) Do you think that ED and C treatment after the shave biopsy messed up my clinical path much?

Any and all comments, including your general interpretation, on this path report and your experience will be helpful. Of course, I will be talking with my doc soon, but wanted to get this board’s collective wisdom.

Thanks,
Sarah
Scheduled for MOHS surgery, late April.