Suggest Treatment For A Sebaceous Cyst In The Back
No, don't worry
Detailed Answer:
Hi and welcome.
I've reviewed the image,
No, this doesn't seem to be soft tissue sarcoma or any other malignant tumor, especially if this lasts for so long. There are also no signs of malignancy on the photo. This was probably a popped vein and subcutaneous hematoma formation after this and then hematoma became fibroma.
This is a normal sequence and more or less visible bump may persist after it. Sebaceous glands it lipoma is also possible but rarely seen on this place.
Bone growth would be hard and deeper. So I don't think that any treatment is required.
If you want to ease your mind you can do an ultrasound with a fine needle biopsy or it can be removed under local anesthesia but I don't think this is also necessary.
Feel free to ask further.
Wish you good health.
Regards