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in situ advice please

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in situ advice please

Posted By
8/13/2010 10:52pm
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Replies: 3

Hi there,

I was diagnosed with melanoma in situ on my upper left arm in May 2010. The original biopsy was done by the dermatologist and I went for a further excision of the area in June. The patho report of the 2nd excision stated that there were atypical melanocytes along the lateral margin. The plastic surgeon felt that with my skin type (fair and freckly) and background (Australian raised) it would be highly likely to find atypical melanocytes anywhere on my body and recommended to leave it and wait and watch. The pathologist recommended a further excision. I spoke with my primary and dermatologist and the derm spoke with the pathologist and I made the decision to go ahead with another, wider excision, in the search for the elusive clear margins. That was 2 weeks ago and I just got the report back and there are more atypical melanocytes. The plastic surgeon thinks I should leave it alone, but said he spoke with the pathologist, and it was suggested that another biopsy, perhaps a punch biopsy, could be taken on the same arm, but 2 or 3 inches away from the original site, to see if there were still atypical melanocytes. The thought is that if more atypical melanocytes are found, it could be fairly safely assumed that it is just my skin's long-term sun damage and not a reflection of any activity relating to the original melanoma. The plastic surgeon was careful to explain to me that atypical melanocytes are NOT melanoma cells, but I understand that the detramination is fairly subjective.

Does anyone have a recommendation for me or experience with similar?

Further, I asked the plastic surgeon to clarify for me that it was still considered "in situ" which he affirmed. I also asked him if a type of melanoma had been identified and he said that "in situ" is the type and that the other types (nodular, lentigo etc) only related to invasive melanoma. I wasn't aware of that.


I appreciate your responses and your help. I have been on here before with the same issues along the way, but feel I need some extra clarification with each step and I am really grateful for your support and advice.



Janner - (8/14/2010 - 12:48am)

Was the degree of atypia specified in the wide excision sample?  I think if it were mildly atypical melanocytes, I might be content to monitor the area for any pigment regrowth.  If the cells were severely atypical, I would want a re-excision now.  I suppose the punch biopsy idea might be ok, but I've never seen that technique mentioned here in the many years I've been on this site.  I have had biopsies on my back which is highly freckled and have not had the same issues with atypical cells.

I would ask for a copy of your pathology reports.  There are types of melanoma - even for in situ.  Lentigo Maligna is one type that is ONLY in situ.  It is called Lentigo Maligna Melanoma when it becomes invasive.  I have also had an in situ lesion that was considered Superficial Spreading Melanoma.  Nodular is rarely found at the in situ stage.  So maybe the communication broke down somewhere.  The pathology report should clarify that.

In the end, do what makes YOU comfortable.  If you want larger margins, then have them.  If you are tired of the cutting and are content to watch the area closely for any pigment changes, then do that.  YOU drive your care!

Best wishes,


mifis - (8/14/2010 - 8:00am)

Thanks Janner,

That certainly complicates things! I specifically asked the plastic surgeon if a type of melanoma had been diagnosed and he said that at the in situ stage there are no types. He went on to say that the various types are only diagnosed once the melanoma is invasive. That is very different from what you are saying and also very different from what I had read.

I only have the first 2 pathology reports so far. On neither of those is there a mention of the degree of atypia (or type of melanoma). The original biopsy report states "there is a residual proliferation of atypical melanocytes noted along the deraml-epidermal junction". The first wider excision states "in block 3, the residual proliferation of melanocytes is virtually transected at a lateral margin".  I have asked for the 3rd patho report to be sent to me and am waiting for it. All three of the reports were prepared by Cleveland Skin Pathology lab in Ohio and I was told that the doctors there are dermopathologists.

Thanks for your response. Any other experiences with something like this out there?



W. - (8/14/2010 - 8:19am)

I wonder whether "Mohs Surgery" could be an option for you (see ).

It is mostly used for melanoma on the face. Not sure whether they also use it for lesions on the upper arm. And it requires a specialist surgeon. But maybe it is worth investigating...