Mesenchymal tumours with melanocytic expression: a potential pitfall in the differential diagnosis of malignant melanoma

Pathology. 2023 Mar;55(2):258-268. doi: 10.1016/j.pathol.2022.12.340. Epub 2022 Dec 28.


Mesenchymal tumours with melanocytic expression can pose a diagnostic challenge because they frequently demonstrate both morphological and immunohistochemical overlap with other cutaneous melanocytic neoplasms. Therefore, they present potential pathological pitfalls that may lead to a misdiagnosis of malignant melanoma. Mesenchymal neoplasms that closely mimic melanoma include malignant melanotic nerve sheath tumour (melanotic schwannoma), epithelioid schwannoma, malignant peripheral nerve sheath, cutaneous syncytial myoepithelioma, clear cell sarcoma of soft tissue, and perivascular epithelioid cell tumour. Awareness of these melanoma mimics is necessary for establishing the correct diagnosis so that the appropriate clinical management can be rendered to the patient. This in-depth review highlights key diagnostic features and molecular genetics and also discusses the differential diagnosis and treatment of mesenchymal tumours that exhibit melanocytic expression.

Keywords: Mesenchymal tumours; malignant melanoma; melanocytic expression; melanoma mimics; pitfalls.

Publication types

  • Review

MeSH terms

  • Diagnosis, Differential
  • Humans
  • Melanocytes / pathology
  • Melanoma* / diagnosis
  • Melanoma* / genetics
  • Melanoma* / pathology
  • Skin Neoplasms* / diagnosis
  • Skin Neoplasms* / genetics
  • Skin Neoplasms* / pathology

Supplementary concepts

  • Melanoma, Cutaneous Malignant