The main differential diagnosis is chondroid syringoma
, which is also known as a benign mixed tumor of the skin, and comprises of bland tumor cell nodules surrounded by a hyaline myxoid stroma commonly admixed with calcifications as well as ossifications.
The incidence of chondroid syringoma
is less than 0.01% of all primary skin tumors.4 They usually present as slow growing, painless, solid, subcutaneous or intradermal nodules with a normal margin.
mixed tumour of skin most often occurs as solitary slowly growing nodule.
Tumors Age groups (in years) 1-10 11-20 21-30 31-40 Sweat gland tumors 1 Chondroid syringoma
1 1 2 Eccrine poroma 1 1 3 Nodular hidradenoma 2 2 4 Apocrine hidrocystoma 5 Syringocystadenoma papilliferum 1 1 sebaceous gland tumors 6 Sebaceous adenoma 7 Sebaceous carcinoma Hair follicle tumors 8 Trichoepithelioma 1 1 9 Trichofolliculoma (Sebaceous) 1 1 10 Pilomatricoma 1 2 2 4 11 Proliferating trichilemmal cyst 1 Total 3 6 6 9 Sr.
: case report and review of the literature.
Based on this pathology, the definitive diagnosis was chondroid syringoma
A chondroid syringoma
is a rare mixed tumor of sweat-gland origin that has both a benign and malignant form.
(57) Mixed tumor of skin is morphologically identical to pleomorphic adenoma of the salivary gland, exhibiting secondary structures such as glands/ducts, cysts, keratinous cysts, and foci of squamous differentiation, with a mucoid stroma typically showing cartilaginous metaplasia (hence also known as chondroid syringoma
Nodular Hidradenoma 5 Malignant 1 chondroid syringoma
Mixed tumors of the salivary gland (pleomorphic adenoma) and sweat gland origin (chondroid syringoma
Auricular ossification has also been associated with inflammatory conditions such as chondritis, perichondritis, and syphilitic perichondritis, as well as with neoplasms such as nevi of the face, pilomatrixoma, and chondroid syringoma
. (4) Finally, many systemic diseases can lead to auricular ossification, including congenital plaque-like osteomatosis, Albright hereditary osteodystrophy, fibrodysplasia ossificans progressiva, Addison disease, osseous heteroplasia, and collagen vascular diseases, especially CREST syndrome and childhood dermatomyositis.
of the skin is nearly identical to PA morphologically, and PLAG1 expression can be detected by IHC; while some authors (10) have reported PLAG1 gene rearrangements, this has not been the case in all series.