Malignant Chondroid Syringoma (Malignant Mixed Tumor of Skin), from the CureRays guide library.

Malignant chondroid syringoma is a very rare, aggressive sweat-gland skin cancer made of both gland-like and cartilage-like tissue; wide surgical removal is the main treatment, with radiation added when surgery can't fully control it or the cancer reaches lymph nodes.

What it is.

A chondroid syringoma is normally a harmless skin lump — a 'mixed tumor' that contains both sweat-gland tissue and a cartilage-like background. Rarely, a malignant version develops: the malignant chondroid syringoma, also called a malignant mixed tumor of the skin. It tends to occur on the trunk and limbs (somewhat more often than the head and neck, where the benign version is common) and is more aggressive than its benign cousin. Because it is exceedingly rare, treatment isn't guided by large trials but by the principles for aggressive skin adnexal cancers: remove it completely with a wide margin, check the lymph nodes, and add radiation for incomplete removal, high-risk features, or nodal spread. This tumor deserves respect — reported cases show a substantial rate of local recurrence and of spread to lymph nodes, lungs, and bone — so complete surgery and long-term follow-up are essential.

How radiation treats it.

Radiation damages the DNA inside cancer cells so they can no longer divide. For this rare skin cancer, radiation is generally added after surgery to clean up microscopic cells that may linger at the edges of the removal or in nearby lymph nodes, improving local control. Modern machines shape the beam — electrons for shallow skin targets, x-rays for deeper ones — concentrating the dose on the at-risk tissue while sparing the surrounding skin and organs. Treatment is painless, given as a series of short daily sessions, and leaves no radioactivity in your body.

The ways we can treat it.

Adjuvant external-beam radiation. After surgery, shaped electron or x-ray beams treat the tumor bed and any involved node region to destroy microscopic cells left behind, lowering the chance of local recurrence.

Radiation for nodal or bone spread. Focused radiation can control disease in lymph nodes or relieve pain from spread to bone, delivered over a series of painless daily sessions.

Questions we hear often.

Is this related to a benign skin lump I might have heard of? Yes. The benign version, a chondroid syringoma or 'mixed tumor,' is a common harmless skin nodule. The malignant version is very rare and far more aggressive. Sometimes it develops within a benign lump that suddenly starts to grow.

What is the main treatment? Complete surgical removal with a wide margin is the cornerstone. Mohs surgery may be used in sensitive areas. Because the tumor can spread to lymph nodes, those are checked, and radiation is added for high-risk features or nodal involvement.

Does it tend to come back? It can. Reported cases show a meaningful rate of local recurrence and of spread to lymph nodes, lungs, and bone. That's why complete surgery, careful node evaluation, and long-term follow-up are so important.

This guide is informational only. It is not medical advice — please confirm anything here with your care team.