The rare neoplasms generally do not follow a determinate development path and are often difficult to diagnose.Histologically, these malignant mixed tumours have epithelial and mesenchymal components and are very large, nodular, circumscribed, and nonulcerated. They are morphologically identical to pleomorphic adenoma and have a female predilection. They range from developing deep dermal to subcutaneous nodules and metastasise at a very high rate. Malignant mixed tumours can emerge "de nova or more rarely develop from a cartilaginous syringoma. "(IADVL, 2004)

Causes
Currently malignant mixed tumours do not have a definitive predisposing factor; however, prior physical injury has been proposed as a potential risk for the emergence of these tumours. Chondroid syringoma less than three centimetres are shown to have a heightened risk of malignancy. Other critical indicators include excessive mucoid matrix, – a connective tissue tumour with a myxoid background that is composed of "clear, mucoid substance – numerous mitoses, and poorly differentiated chondroid components." (Metzler, Schaumburg-Lever, Hornstein, and Rassner, 1996)

Diagnosis
Diagnosing malignant mixed tumours is difficult as there many types of tumours and their variants. Malignant chondroid syringoma is particularly challenging to distinguish from other skin tumours as it is prone to the absence of definitive symptoms and an ambiguous clinical presentation. Some signs that help determine diagnosis of malignancy include: "mitosis, nuclear atypia, pleomorphism, lymphatic invasion, and local recurrence" (IADVL, 2004). Though it is usually found within women in the forties, the youngest-recorded case was fourteen years old and the oldest was eighty-six.
(Ka, Gnangnon, and Diouf, 2016)

See also
List of cutaneous conditions
Neoplasm


== References ==