Is the lump on my wrist cancer?

In short

Most lumps on the wrist and hand are ganglion cysts, which are benign fluid filled swellings, and no one can tell you what yours is from a description. Dr. Knight examines the lump, arranges imaging where it is needed, and sends anything he removes to the lab for a pathology report.

Written for patients by The Hand and Wrist Institute. Prepared for review by John T. Knight, MD. Last updated September 5, 2026How we write and review

Call (817) 382-6789 to have this looked at, or book online with Dr. Knight.

What a hand surgeon is actually looking at

Feel around the edges of the lump with a fingertip from your other hand. That is the first part of the exam, and Dr. Knight does three things with it. He notes where it sits, because the back of the wrist, the palm side, the base of a finger and the fingertip each have their own usual residents. He notes what it feels like, because a sac of fluid, or what we call a cyst, behaves differently under a fingertip than a solid lump of tissue does. He notes what it has done over time, because something that has grown steadily for months is a different story from something that swells with a heavy week and settles with rest. Nothing here substitutes for that exam. We are here to give you information, not to work out what your lump is over the internet.

A fluid filled cyst and a solid lump are not the same thing

This is the distinction underneath the question. A ganglion cyst is a sac of thick joint fluid.¹ A solid lump is tissue, and tissue has to be identified rather than drained. Here is what to note before your visit, as observations to hand over rather than a home test that rules anything in or out. Has it changed size at all, or has it only ever grown. Is it soft and movable under the skin, or firm and anchored in place. How long has it been there, and did anything happen to the hand first. Has the skin over it changed, or has anything in the finger become numb or weak. Bring those four answers with you.

What happens, in order

1. The exam. Dr. Knight looks at the lump, feels it, moves the joint under it, and checks the nerves and tendons around it.
2. Imaging, where the exam leaves a question. X-rays are taken in both the Southlake and Dallas offices. Advanced imaging is done at a facility a few blocks from the Southlake office and the results come back to Dr. Knight. An MRI is used to work out the makeup of a mass, and it does not always show a small cyst.
3. Watching, where that is the sensible option. A lump that is not causing symptoms and is not changing does not automatically need an operation.
4. Removal and pathology, where the lump needs to come out or needs a name. Whatever is removed goes to the lab, and that report is what identifies it.

One of the things a hand lump turns out to be is a giant cell tumour of the tendon sheath, a solid benign growth that sits on the tendon and can extend into the joint beside it. Dr. Knight has narrated one of those operations, and the identification came from the pathology report.

When to call us

• The lump has grown steadily over weeks or months rather than changing size with activity.
• It is firm, fixed in place, and does not move when you push it.
• The skin over it has changed colour, broken open, or started to drain.
• You have numbness, pins and needles, or weakness in the fingers on that side.
• The lump is painful at rest or wakes you at night.