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Breast Cancer, Lymph Node Biopsy, and Dissection

In addition to removing the breast cancer through a mastectomy or lumpectomy, doctors need to know whether the cancer has spread beyond the breast. This is done by removing one or more lymph nodes from under your arm on the same side of the affected breast.

Lymph node biopsy and dissection has two main purposes. It removes the breast cancer that may have spread into the armpit (axilla). And it allows the surgeon to stage your cancer by learning how far the cancer has spread. There are two ways to remove and test lymph nodes:

  • Axillary node dissection. This involves removing at least six of the lymph nodes under the arm. These nodes are then sent to a lab where they are checked for cancer. Axillary node dissection is a very reliable way to check the extent of your cancer, but it has a longer recovery and poses complications such as lymphedema (swelling of the arm) or nerve damage compared to sentinel node biopsy.
  • Sentinel node biopsy. In this surgery, a special blue dye and/or a radioactive substance is first injected into the breast in the region of the tumor to determine which lymph nodes are the first to receive drainage from the breast. These nodes would potentially be the first to be invaded by cancer cells. One to three sentinel nodes are usually removed and tested for cancer. Studies show sentinel node biopsy is just as accurate as axillary node dissection in diagnosing cancer, and has fewer complications.

If an axillary node dissection was performed, a drain is placed under the arm to remove fluids that may accumulate and cause swelling and the wound is then closed. After this procedure, you will need to stay in the hospital one to two nights or longer if reconstruction is done. Many women go home with the drain in place. Your doctor will remove it a few days later. Women can soon begin simple exercises taught by a physical therapist to relieve the muscle soreness and tightness common after mastectomy. Pain medication can be taken as needed. Some swelling is common. Additional exercises are possible once stitches are removed. Complete healing takes about six weeks.

Before breast cancer surgery, print out these Questions to Ask so you can better understand your care.

Also before surgery, your doctor should provide:

  • Specific instructions to follow in the days before surgery
  • An overview of the surgical procedures
  • Information about recovery and follow-up care

After surgery, watch for complications such as infection or swelling in your arm or hand. Call your doctor immediately if you see signs of swelling, a build-up of fluid, redness, or other symptoms of infection.

WebMD Medical Reference

Reviewed by Sujana Movva, MD on July 02, 2014

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