David Chang MD

Supermicrosurgery: A New Way to Open Clogged Drains

As many as 25 to 30 percent of women who have breast cancer surgery with lymph node removal and radiation therapy develop lymphedema — a disorder in which lymph fluid accumulates, leading to chronic swelling in the upper arm.

There is no cure. The disorder is difficult to manage. Current therapies use physical manipulation with compression bandages, massage and exercise to lessen symptoms. Many novel approaches to treat or prevent lymphedema have been developed and tested, but with little or no success.

In the last five years, however, “supermicrosurgical” modifications to a 50-year-old procedure — originally known as lymphaticovenous anastamosis — have made the original procedure more effective. Using a microscope and specially designed instruments, surgeons can now reroute the fluid from plugged lymphatic vessels into a nearby blood vein.

These reconstructive procedures, still quite rare, are becoming an attractive option for women when medical treatment does not provide adequate relief.

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The University of Chicago Medicine recently recruited a pioneer in what is now called lymphaticovenular bypass. In September, David Chang, MD, FACS, formerly a professor of surgery at the MD Anderson Cancer Center, came to UChicago. Chang has been a key player in introducing this complex procedure to U.S. operating rooms, and is one of a few surgeons in the country, and the only one in Illinois, who performs it routinely.

“Lymphedema is like a massive traffic jam with no exit,” Chang said. As this protein-rich fluid flows into, but not out of the arm, it causes swelling. This becomes painful and can feed repeated infections.

“Our procedure does a lot to help relieve the problem by offering the fluid a way out,” Chang said. “While it does not totally eliminate the condition, there is very little downside for the patient. We often see significant improvement.”

In a lymphaticovenular bypass, surgeons first use a fluorescent green die to map the lymphatic system in the affected arm. Following this map, they make several small incisions in the swollen arm and use tiny microsurgical instruments under the microscope to connect blocked lymphatic vessels — as small as 0.3 mm in diameter — to a nearby vein.

lymphedema

A patient with a persistent 32% increase in volume received five bypasses, five years after the onset of lymphedema. This produced a 61% excess volume reduction when measured 15 months after treatment. Her left arm is now only 12.6% larger than her right arm.

 

Early attempts at building a new drainage system failed because the surgeons connected the lymph system to large deep vessels with greater pressure levels.

Chang’s team uses lymphatic vessels that lie just under the skin and connects them to smaller veins, also near the surface. These have low pressures, which means less risk of venous backflow. And because lymphedema begins at the shoulder and slowly moves down the arm, surgeons tend to focus on vessels close to the wrist.

The new connection allows much of the excess lymph fluid to drain out of the limb. The procedure usually requires two to five such micro-bypasses and takes about four hours. Patients are discharged in less than 24 hours.

In 2010, Chang and colleagues published a study of 20 consecutive lymphedema patients treated with this technique. Their swollen arms were, on average, 34 percent larger than their normal arm. The average patient was 54 years old and had suffered from lymphedema for almost five years. Ten patients had stage II lymphedema and 10 has stage III.

Soon after treatment, 19 of the 20 patients reported improved symptoms — less pain, lighter weight, softer skin. When tested three months after surgery, 13 patients had measureable improvements, including a 36 percent average volume reduction in their affected arms. After six months, that rose to 39 percent volume reduction. It declined slightly, to 35 percent, at one year. A larger study, following almost 90 patients, is still underway and producing similar results.

Since then, Chang and colleagues have learned how to predict which patients will benefit most. Patients with stage 1 or stage 2 lymphedema lose more than half of their excess volumes: a 58 percent reduction at three months and 61 percent at 12 months. Those with stage 3 or stage 4 lymphedema however, saw limited change.

“What we learned from this study is that not every lymphedema patient is a candidate for this operation,” Chang said. “Our approach is best suited for patients with stage 1 or stage 2 lymphedema, before the disease progresses to more severe forms, with widespread fibrosis, that are extremely difficult to treat.”

“Because our follow-up data are preliminary, it remains unclear whether lymphaticovenular bypass provides a benefit beyond 5 to 10 years in breast cancer patients with lymphedema,” Chang cautioned. Long-term data and better preoperative and postoperative evaluation methods are needed.

He is extending this approach, testing whether lymph-node clusters transferred from the armpit to the ankle can prevent swelling in the legs following pelvic surgery for gynecological or pancreatic cancers.

It may also work in the other direction, moving lymph nodes from the groin to the axilla to prevent the disorder in breast cancer patients.

“There is always room for improvement in this realm,” Chang said. Certain features of the lymphatic system, such as its transparency, fragility, and numerous valves, have made it difficult to study, but this is an area that will evolve. Different techniques will boost our understanding of the lymphatic system and lymphedema prevention and treatment.”

About the Author

Posted on:
October 3, 2013

Author:
John Easton
Sr. Science Writer

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