What do doctors do to remove a sebaceous cyst?

Minor Surgery. A non-infected sebaceous cyst is removed under local anesthesia through a small incision placed over the cyst. The cyst needs to be removed whole to prevent recurrence, so the incision is about the length of the cyst. The sooner it is removed, the smaller the incision. Infected cysts are lanced and can be excised after the infection has healed.
With a minor surgery. Numb up the skin. Make a small incision directly over the cyst. Remove the cyst completely, including the cyst wall. Sew it up neatly.

Related Questions

How do doctors remove sebaceous cyst on the scrotum?

SEBACEOUS CYSTS. The most effective way is to excise them entirely removing the knis tissue within that caused them.
See below. Usually under local anesthesia. The cyst gets excised with a small section of surrounding skin. It's a quick and painless procedure as long as the cyst is not infected.

How can a doctor remove sebaceous cyst on scrotum?

Small incision. A sebaceous cyst has to be removed entirely. No matter where the cyst is located the entire cyst wall and contents needs to be removed. This is generally done with local anesthesia and a small incision.

Had sebaceous cyst removed from my neck a week ago by doctor, now have a lump there twice the size of the original cyst, how is this possible?

From a hematoma. It is possible that some bleeding in the area has occurred causing a hematoma. Also, it could be from an accumulation of serous fluid resulting in a seroma. Best thing to do is to go see the doctor who preformed the surgery.
Hematoma? Fluid? The space that used to hold the cyst probably filled with fluid or blood. Should go down with time. If not, see your surgeon.

I had a sebaceous cyst removed 6 weeks ago and still have a red mark from the incision/sutures. Is this normal or should I follow up with doctor?

Probably nornmal. Many scars remain reddish and firm for 3-4 months. If it is not very painful to touch, and the redness is limited to the area around the incision and isn't spreading, it is probably normal. If you have any concern, though, contact your physician.
Pretty normal... Scar maturation is a process that can take 6-12 months. Metabolic activity in a scar peaks about 6-8 weeks after the injury (or surgery) and it is common for scars to become more red, raised, and itchy at that time. It should gradually improve with the passage of time. If not, you should return to the surgeon who performed the procedure.