Armed with new laparoscopic and microsurgical techniques, surgeons are revisiting the use of omental flaps to safely and effectively treat lymphedema in breast cancer patients.
“Lymphedema is a horribly morbid disease without a cure,” said Alexander Nguyen, M.D., an assistant professor in the Department of Plastic Surgery at The University of Texas MD Anderson Cancer Center. Paraphrasing the consensus statement of the International Society of Lymphology, he added, “The closest thing we currently have to a cure is microsurgery.”
Vascularized lymph node transfer—in which lymph nodes are transplanted from one part of the body to another using microsurgical techniques—has been shown to improve lymphedema symptoms and reduce the volume of affected limbs. In some cases, however, the use of such flaps can cause lymphedema at the donor site.
In search of a donor site
The groin and supraclavicular lymph nodes are often used as donor sites for vascularized lymph node transfers to treat lymphedema of the arm. However, the removal of lymph nodes from these sites sometimes results in lymphedema of the leg or contralateral arm. The safety of lymph node transfers has been improved by a treatment algorithm developed by Dr. Nguyen and colleagues in the Department of Plastic Surgery. Dr. Nguyen has also worked with Franklin Wong, M.D., Ph.D., a professor in the Department of Nuclear Medicine, to map the lymph nodes in the donor sites so that surgeons can identify and spare those most essential to the limb.
Despite measures that reduce the likelihood of donor site lymphedema following lymph node harvest, the possibility remains. This is especially true for obese patients, who are at higher risk for postoperative lymphedema. “Unfortunately,” Dr. Nguyen said, “a person who is at risk for lymphedema in the upper extremity may also be at risk for lymphedema of the lower extremity.” To find lymphatic tissue that could be harvested without causing lymphedema elsewhere in the body, Dr. Nguyen revisited a donor site that had shown promise in the past: the omentum.
New techniques for an old idea
In addition to its abundant lymphatic structures, the omentum has immunogenic properties that fight infection. Dr. Nguyen reasoned that these properties would benefit patients with lymphedema, many of whom experience recurring infections in the form of cellulitis or lymphangitis.
Using the omentum as a flap donor site for lymphedema treatment was not a new idea. Surgeons performed omentum transfers to treat lymphedema of the arm and leg more than 40 years ago, but there were risks associated with the open procedure used to access the omentum and especially with the use of a pedicled flap. “Forty-plus years ago, surgeons needed to open the abdomen and didn’t transfer the omentum as a free flap; they left it attached to the blood supply,” Dr. Nguyen said. “This left a large incision to recover from and a vascular clothesline for the intestines to get twisted around, and patients had bowel obstructions and other devastating complications.” Thus, even though using the omentum as a donor site yielded good results for the lymphedema—over 50% of patients reported improvement—surgeons stopped performing the procedure because of the risks involved.
Dr. Nguyen and Hiroo Suami, M.D., Ph.D., an assistant professor in the Department of Plastic Surgery, hypothesized that modern surgical techniques could reduce these risks while improving the lymphatic quality of the flap. “We have a team of surgeons who are cross-trained in various techniques,” Dr. Nguyen said. “So we developed a procedure that combines supermicrosurgery, routine microsurgery, and laparoscopic surgery to perform a laparoscopic free omental lymphatic flap transfer.”
In the new procedure, surgeons use a minimally invasive technique to harvest the omental lymphatic tissue. “We map the lymphatic structures of the omentum,” Dr. Nguyen said, “and then we harvest the critical lymphatic structures of the right half of the omentum, which has more lymphatic structures and larger blood vessels.”
The flap is transplanted to the recipient arm or leg and can be placed proximally or distally as determined by preoperative imaging and physical examination. Microsurgical techniques are used to anastomose blood vessels in the omental flap to both an artery and a vein to provide adequate perfusion. The surgeon also performs a lymphovenous anastomosis, connecting the lymphatic vessels in the flap with the venous draining system.
The omental flap’s lymphatic structures are mapped intraoperatively using lymphography. “When we inject the indocyanine green dye into the flap, it just flies through the omentum, confirming its lymphatic effectiveness,” Dr. Nguyen said. “In lymph node transfers from other donor sites, the dye doesn’t move as quickly; it just sits there.” Similar results are seen on postoperative lymphograms.
The new procedure was first performed in November 2013 in two patients with lymphedema of the arm following surgery for breast cancer. “These patients’ lymphedema has improved, their arms are lighter, and the skin quality is better—the skin used to be like leather, and it’s now softer,” Dr. Nguyen said. He added that both patients had experienced frequent infections in their lymphedematous arms before surgery but not afterward.
Dr. Nguyen has since seen similar results in more than 20 patients treated with the procedure. Only one patient experienced flap loss, Dr. Nguyen said, and this most likely was caused by concurrent venous hypertension of the leg. None of the patients has had donor site complications.
“We’ve had success early on,” Dr. Nguyen said. “I’ve had patients who no longer wear compression garments and who are off the maintenance antibiotics they needed for recurrent infections.”
The infection-fighting properties of the omentum also make omental flaps useful for other reconstructive procedures. Dr. Nguyen said he has used laparoscopic omental flap transfers to repair pelvic defects, perform scalp reconstructions, cover chest defects, and correct breast reconstruction defects. These flaps have also been used to treat head and neck lymphedema.
For cancer survivors with lymphedema of the arm or leg, Dr. Nguyen said, the omental flap offers promise as an effective treatment without the risk of lymphedema in another limb near the donor site. “Compared to the groin or supraclavicular flap, I think that the omental flap is much more powerful,” Dr. Nguyen said. “Long term, this may be the game changer.”
Left: An omental flap removed laparoscopically is ready to be used as a free flap in a lymphedematous limb. Right: Fluorescence imaging highlights the omentum’s lymphatic structures. Images courtesy of Dr. Alexander Nguyen.
For more information, contact Dr. Alexander Nguyen at 713-794-1247.
Nguyen AT, Suami H. Laparoscopic free omental lymphatic flap for the treatment of lymphedema. Plast Reconstr Surg. 2015;136:114–118. (Supplemental video: http://links.lww.com/PRS/B336.)
OncoLog, October 2015, Volume 60, Issue 10