title: [Malignant transformation of an eccrine spiradenoma].
abstract: BACKGROUND
  Malignant eccrine spiradenoma is a rare and aggressive tumor, developed on the epithelium of eccrine sweat glands. Typically, it occurs after malignant transformation of benign eccrine spiradenoma, but sometimes it happens de novo.
  
  
  METHODS
  We report a case of malignant eccrine spiradenoma in a 62-year-old woman. The patient presented a rapid increase in size of a long-standing tumoral lesion of her forearm. There was no secondary lesion on the chest, abdomen or pelvis at the CT-scanner. Cutaneous biopsy of the lesion was performed and showed a carcinoma with no contact with epidermis. On this biopsy, we could not affirm if the tumor was a metastatic process or a primary tumor of the skin. Histologic examination of the surgical removal of the tumor showed an undifferentiated carcinoma with adjacent nodules of eccrine spiradenoma. Immunohistochemical assessment of Ki67 expression showed a weak expression (5%) in the benign spiradenoma nodules and a high rate expression (80%) in the malignant neoplasm. The final diagnosis was an undifferentiated carcinoma arising from preexisting benign spiradenoma.
  
  
  CONCLUSIONS
  Malignant eccrine spiradenoma is not frequent and is rarely described in the international literature that may lead to diagnostic difficulties.
authors.affiliation: Service de pathologie, centre hospitalier Lyon sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Bénite, France. Electronic address: julienjacquemus@yahoo.fr.
authors.forename: J
authors.initials: J
authors.lastname: Jacquemus
authors.affiliation: Service de dermatologie, centre hospitalier Lyon sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Bénite, France.
authors.forename: S
authors.initials: S
authors.lastname: Dalle
authors.affiliation: Service de dermatologie, hôpital Édouard-Herriot, 5, place d'Arsonval, 69003 Lyon, France.
authors.forename: M
authors.initials: M
authors.lastname: Faure
authors.affiliation: Service de pathologie, hôpital Édouard-Herriot, 5, place d'Arsonval, 69003 Lyon, France.
authors.forename: B
authors.initials: B
authors.lastname: Chouvet
authors.affiliation: Service de chirurgie, centre hospitalier Lyon sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Bénite, France.
authors.forename: O
authors.initials: O
authors.lastname: Beatrix
authors.affiliation: Service de pathologie, centre hospitalier Lyon sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Bénite, France.
authors.forename: B
authors.initials: B
authors.lastname: Balme
mesh_terms: D018250:Acrospiroma / Q000473:pathology* / Q000601:surgery; D001706:Biopsy; D002277:Carcinoma / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D005542:Forearm / Q000473:pathology; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D013544:Sweat Gland Neoplasms / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome
keywords: Carcinome sudoral; Eccrine spiradenoma; Malignant transformation; Spiradenocarcinoma; Spiradénocarcinome; Spiradénome eccrine; Sudoral carcinoma; Transformation maligne