Case discussion: How would you treat this patient? [20 March]

This week’s case discussion, submitted by Dr Robert Teunisse, features an 80-year-old male patient with a past history of two melanomas in situ.

Dr Teunisse noted two suspicious lesions on the patient’s back during his routine skin check. The first is on the right scapula. What do you make of this lesion? What would you do next?

(We will cover the second suspicious lesion in next week’s case discussion, coming Monday, 27 March.)

case discussion


Here is the pathology report!

case discussion

For further information on this topic, you may be interested to learn more about the HealthCert Professional Diploma program in Skin Cancer Medicine.

case discussion


Would you like to obtain advice or share your experience with your colleagues in the weekly blog case discussion, moderated by Dr Terry Harvey?

 Participate with your cases so that we can learn together!

Submit your case here or send details to [email protected]





Leave a Reply

Your email address will not be published. Required fields are marked *

28 comments on “Case discussion: How would you treat this patient? [20 March]

  1. Asymmetrical shape, features and colours
    Border iiregular and blurred in places
    Multi colours
    Diameter greater than 5mm
    Elevation asymmetrical
    ?? Melanoma in situ or superficial spreading

    1. Hi Sheena

      Can a melanoma be both in situ AND superficial spreading?

      What is the different between melanoma histological subtypes and melanoma depth?

      Which is which from your comment?


      1. Follow up question on melanoma in situ: if a melanoma grows laterally but does not invade the basement membrane would that be a melanoma that is both in situ and spreading?

        1. Hi Kim

          “Superficial Spreading” is a histological subtype of melanoma. It is defined by the growth pattern seen histologically, and not by whether a melanoma is in situ or invasive.

          Superficial spreading melanoma starts off in situ, but can become invasive. So you can have both an “in situ superficial spreading melanoma” or an “invasive superficial spreading melanoma”.

  2. A chaotic lesion. Having a sharp boarder some crypts and millia like cysts, could fit an irritated seborrheic keratosis. However some possible Melanoma clues re blue eccentric structure. Some thickening of the net work. Milky red areas with some polymorphic BVs. Asymetrical and variable globules. Impression = a melanoma until proved otherwise, hence a 2mm margin elliptical excision.

    1. Hi Graham

      I think you’ve correctly identified some important features of seborrheic keratosis in the images. The question then always comes down to weight these features against some features that can be seen in melanoma.

      Some melanoma clues are more sensitive than others, and some melanoma clues are more specific than others. There are many situations like this where knowing the difference can be useful


  3. With his history and the Dermoscopy appearance this lesion requires an
    Excisional biopsy to rule out melanoma

  4. With that history and the doppled pigmentation, with asymmetry , suspicious for another melanoma –excision biopsy

  5. The patient need to do excision biopsy. I look for information I hope to make use of this tendency to encourage the immune system to attack melanoma cells. The other observation is that when poisonous snake is attached to a cells surface it attracts the attention of T lymphocytes.

  6. suspicious irregular lesion
    dark spots , blood vessels
    need excision biopsy, with 5 mm margin
    high risk patient

  7. The lesion is certainly irregular enough to to an excisional biopsy with 2mm margin. I think this is pretty clear.

    I think the only thing too add is whether you just go ahead and take a 5-10mm excisional biopsy to save the patient further surgery. Given the location and the subsequent low morbidity from a larger excision I would be very tempted to do this.

    1. Hi Anonymous

      I would be careful trying to ‘bend the rules’.

      If you performed a 10mm margin because you thought this was invasive melanoma, and then the result was invasive melanoma of 1.5mm Breslow – you have actually decreased the accuracy of future staging through sentinel lymph node biopsy. This can cause headaches with staging and at worst limit patient access to adjuvant treatments.

      If you perfomred a 10mm margin excision and the result is seborrheic keratosis – you have performed a very large procedure for a lesion that required no treatment at all.

      2mm margin excisional biopsy remains the recommended method for diagnosis of suspicious pigmented lesions.

      1. Seriously , just why are so many people so keen to charge for excision when shave will tell you what it is .
        Of course if one cannot confidently identify a sebK give the dermatoscope to someone else!
        There is but one reason to excise a pigmented lesion and that is because it is considered a skin cancer (MM or pigmented BCC) then the appropriate margins are required , if you cannot close the hole then let someone who can do so do it .
        SLNB is still prognostic and only still confirms the prognosis based on both Clarks (for those who know the anatomy of skin) or Breslows (for those whom have just learned to use a ruler) .
        If you are going to give someone the JAK remember it is still done more in hope than certainty.

        1. Hi Tom

          Thanks for your comments. There are plenty of opinions on both sides of the shave vs excision debate.

          I tend towards excisions where able for a number of reasons – including one related to what you have mentioned there in that I am suspecting a cancer. If I perform an excision with 2mm margins, and the pathologist incorrectly diagnoses a dysplastic naevus when the lesion was in fact a melanoma; then I have already provided the patient with 95% of the important melanoma treatment by excising the lesion.

          I’ve spoken to a patient just today who expressed his frustration at the broad flat shave scars (performed elsewhere) on his body that were slow to heal, and explained how much easier it was for him to take care of an excision wound with internal sutures. I find this is not uncommon among patients who have had shave saucerizations. If I perform a 10x10mm and 1mm thick saucerization shave excision and a 2mm excisional biopsy with internal sutures distal to someone’s knee – which is going to require more aftercare and dressings?

          I do think there are times where a shave excision is a useful option (e.g. large facial lesions, areas where full thickness excision may carry high morbidity, or where a patient can’t return (or I can’t trust them to return) for an excision procedure for logistic reasons). However with the resources I have available a full thickness 2mm excisional biopsy remains easy and fast to perform and thus I favour it and national guidelines reflect that also.

          I can’t justify a 10mm margin excision on an undifferentiated lesion though!

  8. 5mm brown-black macula on right upper back of 80 yo male with Fitzpatrick 2-3 skin and past history of 2 melanomas.
    Dermoscopy with chaos (asymmetry of colour) and clues (eccentric structureless area, thick lines reticular, grey/blue structures, vessel polymorphism).
    This lesion is suspicious.
    Requires excision bx with 2mm margin.

  9. 6 x 4 mm irregular pigmented lesion R upper back approx. mid-clavicle region. Sun damaged skin w. multiple lentigo and scar from possible previous excision 3 cm superior.

    Eccentric irregular darkly pigmented area L inferior part of lesion with blue/grey/white veil parts, thickened network superior and other parts. Areas of regression, Polymorphous vessels – glomerular, comma and possibly hairpin like appearance.

    Chaos and clues in abundance. MM until proven otherwise. Only reasonable differential I can think of is traumatised Seb K. Excise with 2 mm margins

  10. Past h/o melanoma, irregular border, variable colour,complete loss of pattern, Melanoma will be my first diagnosis. To determine the level,staging, depth, I suggest an excisional biopsy with 2 mm margin and then final treatment depending upon the result.

  11. The lesion is asymetrical and multi coloured with irregular pigment network and peripheral radial streaming with blue-grey veil indicating high chance of Melanoma -in-situ or superficial spreading melanoma.

  12. Hi Everyone

    This lesion showed a lot of hallmark features for seborrheic keratosis.
    – milia cysts
    – abrupt borders
    – structureless brown pigmentation

    The vascular areas centrally for me are most consistent with an seborrheic keratosis and angioma collision lesion. This isn’t uncommon as they occur through very similar distributions.

    I don’t see an specific melanoma clues here, only sensitive ones that occur in many other lesions also. Structureless areas and thickened reticular lines both occur in seb K. These can be great mimics, and there are obviously some seborrheic keratoses that unfortunately need excision to exclude melanoma.

    Finding melanoma can sometimes be the easy part. The tough part can be accurately diagnosing benign lesions to decrease the costs, surgical scars, and surgical risk you exposre your patients to in the process.