Case Number : Case 78 Posted By: Guest

Ruifeng Guo - OUHSC (OK, USA) Wrote:

Thanks a lot for your encouragement, Dr. McKee. I am pretty sure some of my fellow residents are also very interested in this spot diagnosis discussion. It is so great to have such a wonderful learning resource for us.

Submitted on 28/09/2010 01:20
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Phillip McKee - Overseas consultations (Arizona, USA) Wrote:

The final diagnosis is Merkel cell carcinoma with a trabecular growth pattern. The vast majority of you appreciated that this was a basaloid tumour with features of a Merkel cell carcinoma; naturally immunohistochemistry would be performed to confirm the diagnosis.

Submitted on 27/09/2010 23:46
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ANDREW DANCKWERTS - WITS UNIVERSITY (JOHANNESBURG, RSA) Wrote:

HIGH GRADE MALIGNANT NEOPLASM WITH A TRABECULAR GROWTH PATTERN: DDx - MALIGNANT MELANOMA, MERCKEL CELL CARCINOMA OR METASTATIC CARCINOMA. I WOULD LIKE TO DO IMMUNOHISTOCHEMISTRY TO CONFIRM - CK20, HMB45, S100, SYNAPTOPHYSIN, CHROMOGRANIN A, EMA.

Submitted on 27/09/2010 19:55
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Lushen Pillay - Wits Dermatology, South Africa (South Africa) Wrote:

Merkel Cell Ca

Submitted on 27/09/2010 19:55
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Phillip McKee - Overseas consultations (Arizona USA) Wrote:

Dear Ruifeng Guo, I am really pleased you are making the effort to proffer a diagnosis on this case. Please continue to do so and encourage your residents and fellows. The seasoned dermatopathologists are all heading in the right direction! Will reveal all later!

Submitted on 27/09/2010 15:36
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Yamile Corredoira - Universidad de Chile (Santiago - Chile) Wrote:

Neuroendocrine carcinoma, either metastatic or Merckel.

Submitted on 27/09/2010 14:47
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Marcela Saeb Lima - Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (Mexico City) Wrote:

Merkel cell carcinoma

Submitted on 27/09/2010 13:38
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Mona Abdel-Halim - Dermatology Department, Faculty of Medicine, Cairo University (Egypt) Wrote:

Merkel Cell Carcinoma with the rare trabecular pattern.

Submitted on 26/09/2010 20:26
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Ruifeng Guo - OUHSC (Oklahoma City, OK, USA) Wrote:

I zoomed in this picture and start realizing that a lot of nuclei are truly round, or close to round, with a little glassy chromatin,and eosiniphilic cytoplasm. After checking some books, it seems that Merkel Cell Carcinoma can also occasionaly take trabecular pattern. This makes me think that MCC should be more possible than melanoma. CK20, EMA, S100 and HMB45 should be able to tell the truth.

Submitted on 26/09/2010 06:36
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Ruifeng Guo - Pathology Department, OUHSC (Oklahoma City, OK, USA) Wrote:

Let me provide some first year resident input. Subcutaneous centered tumor,trabecular pattern, active mitosis. However, the nuclear features don't look like merkel cell carcinoma (neither round nor oval, clear space in nuclei). At the left upper corner, it looks the lymphocytes are attacking this tumor (I am not sure about the significance of this finding). Although I still haven't got a clear clue about this based on my limited knowledge, I want to make a brave guess: trabecular pattern malignant melanoma.

Submitted on 26/09/2010 05:19
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Marwa Fawzi - Dermatology Department, Faculty of Medicine, Cairo University (Egypt) Wrote:

Merkel cell carcinoma

Submitted on 25/09/2010 23:55
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