Chondroid syringomas present as small (0.5-3 cm), painless, slow-growing masses in the head and neck region. They are typically solitary dermal or subcutaneous nodules found in middle-aged men, although cases of multiple tumors, larger tumors, and tumors in various locations, across ages, and in both sexes have been reported.
Malignant transformation of mixed tumors of the skin is very rare. Malignant forms tend to grow rapidly and occur more commonly on the lower extremities of younger females. Metastasis to regional lymph nodes, bone, and visceral organs may occur.
Chondroid syringomas are rare, representing less than 0.1% of cutaneous tumors. Given their low rate of incidence and nonspecific clinical presentation, they are rarely a preoperative diagnosis of skin tumors. Definitive diagnosis requires total excision and histopathologic examination.
D23.9 – Other benign neoplasm of skin, unspecified
302828001 – Syringoma of skin
Differential Diagnosis & Pitfalls
- Pleomorphic adenoma – Common, benign mixed tumor of salivary glands that can develop in all major and minor salivary glands.
- Epidermoid cysts – Benign cysts commonly on the face, trunk, extremities, mouth, or genitals. Often dome shaped with a punctum and expressible cheesy material.
- Lipoma – Benign, slow-growing soft tissue tumor of white fat cells that often appears on the neck, trunk, extremities, and buttocks. Nontender, mobile, solitary or multiple and usually occurs between the fourth and seventh decades of life.
- Neurofibroma – These asymptomatic skin-colored or violaceous nodules can arise anywhere on the body, most commonly on the head, neck, and upper trunk. When compressed, the buttonhole sign is a strong diagnostic clue.
- Dermoid cyst – Present at birth, these appear on the head, commonly along the lateral eyebrow.
- Dermatofibroma (histiocytoma) – A common, benign skin tumor that is often present on the extremities. Squeezing laterally on nodules will pucker skin inward in a characteristic dimple, or Fitzpatrick's sign.
- Pilar cyst – Common, benign cysts of hair follicular origin that present on the scalp. Firm, smooth, and mobile, there are often multiple cysts, and they may rupture and extrude their contents or form cutaneous horns.
- Abscess – Erythema, induration, and discomfort are often present.