Keloid scars can be a tough problem.
It is first very important to differentiate between a hypertrophic scar and a keloid scar.
The treatment for each type is quite different.
A keloid is a progressive growth that extends past the original scar and invades and destroys normal skin and tissue.
A hypertrophic scar is just a widened thick scar due to excessive tension.
These are common on the upper back, between the breast and upper arm.
These are all areas of excessive tension.
The stimulus for a keloid is inflammation.
Anytime the skin is injured, from a cut, incision, or infection the healing process is started.
This involves a complex array of cells.
Early in the healing process mast cells release histamine.
This histamine attracts fibroblasts.
Fibroblasts are the cells responsible for the production of collagen.
Collagen is the body's building block for scar formation.
In the typical individual this histamine signal is turned off at about 6 weeks.
For the keloid former this signal never stops.
This is why a keloid scar itches.
It is a response to the histamine reaction in the skin.
More and more scar tissue is formed and formed abnormally in the keloid patient.
A good way to explain this is to consider a wound like a construction site.
Normally there is an initial flurry of activity as more material and equipment are brought in to perform the various tasks.
For a scar this peak of activity occurs at about 6 weeks.
Next the body makes enzymes that remodel the scar bringing it down to its final appearance.
This is why all incisions and wounds initially appear inflamed, and then they become thick, hard, red and raised.
This reaches a peak at 6 weeks.
The final phase of wound healing is maturation where the scar is remodeled and eventually reaches is final matured version.
There has really been very little that is new in the treatment of this condition over the past 20 years.
The standard treatment protocol involves

1. The injection of Kenalog which is a steroid
2. Radiation
3. Pressure
4. 5 FU - 5-fluorouracil

For the difficult recurrent or refractory keloids I usually suggest the following treatment protocol

1. Excision of the keloid, under minimal tension, using suture material that dissolves by hydrolysis and not by inflammation.
   The synthetic suture material dissolves by hydrolysis while the non-synthetic material such as chromic dissolves by inflammation.
   
2. At the time of excision you can consider injection with a Steroid such as Kenalog and the addition of a chemotherapeutic agent such as 5 FU.
   There have been several recent studies discussing the benefit of this additional drug therapy to the management of keloids.
   
3. Taping of the incision immediately after the procedure reduces overall tension and can be beneficial
4. Silicone gel sheeting has been advocated
5. Codran tape this tape contains Flurandrenolide which is a potent corticosteroid for topical use
6. Radiation can be effective; typically the incision will be treated with a low dose of radiation about 2 days following the excision of the keloid.
   

Any incision, to remove a keloid, can start the whole process over again.
A good evaluation by a plastic surgeon and a keen understanding of the process of keloid formation can help correct the problem, or at least make it better.