A new surgical breakthrough builds fences around tumors

Some tumors grow not as a single lump, but as tangled, vine-like networks that wrap around nerves, blood vessels, and muscles. These are plexiform neurofibromas, rare, sprawling tumors that can cause severe disfigurement, pain, and disability. For people with Neurofibromatosis Type 1 (NF1), a genetic condition that affects about one in 3,000 people worldwide, these growths can become life-altering. Removing them has always been one of the biggest surgical challenges in medicine, until now.

In a study published in the Chinese Journal of Plastic and Reconstructive Surgery, a team of surgeons from the Shanghai Ninth People's Hospital, part of the Shanghai Jiao Tong University School of Medicine, introduced an ingenious new surgical technique called FENCY ligation, and it's giving new hope to patients once considered inoperable.

The research details a method that quite literally builds a "fence" around these massive tumors before cutting them out. The results? Dramatically reduced bleeding, faster recovery, and safer surgeries for some of the most complex cases ever attempted.

Neurofibromatosis Type 1 (NF1) is a hereditary condition that causes nerve tissue to grow into benign tumors throughout the body. Most are small and harmless, but plexiform neurofibromas (PNFs) are different. They can stretch across entire regions of the body, especially the face, neck, or limbs, sometimes reaching sizes over half a meter wide or weighing more than 10 kilograms.

What makes these tumors so treacherous isn't just their size, it's their blood supply. They're filled with fragile, dilated blood vessels, turning every surgery into a potential battlefield. Surgeons have likened removing a giant PNF to "operating on a bag of live worms filled with blood." In some cases, patients can lose liters of blood within minutes if even a small vessel ruptures.

Over the years, doctors have tried everything, electrosurgery, adhesives, vessel sealers, even targeted drugs like selumetinib (a MEK inhibitor) to shrink the tumors. But for massive PNFs, surgical removal remains the only way to truly restore function and appearance. The problem has always been how to do it safely.

That's where FENCY ligation comes in, a deceptively simple idea that reimagines how surgeons prepare to remove these complex tumors.

Before cutting, the Shanghai team uses heavy silk sutures to tie off blood vessels in a "fence-like" circle around the tumor. Think of it as building a barrier, one stitch at a time, that seals off the tumor's blood supply from surrounding healthy tissue. Once this "fence" is complete, the surgeons can safely remove the tumor with far less bleeding.

In some especially vascular cases, the doctors go one step further: they perform preoperative embolization. That means using tiny metal coils to block the arteries feeding the tumor days before surgery. It's like shutting off the water mains before repairing a burst pipe.

When combined, these two techniques, embolization and FENCY ligation, proved remarkably effective.

Between 2019 and 2024, the team at Shanghai Ninth People's Hospital treated 456 patients with plexiform neurofibromas. Among them, 11 had "giant" tumors, the kind that most hospitals would consider inoperable. Seven of these patients were women, ranging in age from 9 to 44 years old. The tumors were massive: the median diameter was 30 centimeters, with one measuring over 55 centimeters** across.

Most of the tumors were on the face, often distorting vision, breathing, or swallowing. Others affected the back, limbs, or buttocks, causing severe pain or immobility. With FENCY ligation, and embolization in three of the toughest cases, the team achieved something unique. The average blood loss is only about 366 mL (less than a can of soda). The hospital stay was reduced to around 17 days. There were no serious complications, except one minor infection. Also, patient satisfaction was near-perfect, most rated their results 9 or 10 out of 10. One patient, a 23-year-old woman, had a 14-kilogram tumor removed from her back and buttocks without major bleeding. Less than two years later, she walked back into the clinic upright and smiling, her mobility restored, her life reclaimed.

For surgeons, controlling bleeding during giant tumor surgery is everything. Traditional methods, like using a tourniquet to squeeze blood flow, don't work for tumors on the face or trunk. FENCY ligation, by contrast, works anywhere, even in the body's most complex landscapes.

Patients with giant facial or body neurofibromas often face social stigma and emotional trauma, in addition to physical suffering. Many live reclusive lives, afraid to appear in public. A safer surgery means not only medical recovery but dignity. And also the chance to re-enter society, work, and relationships.

The Shanghai team's approach also offers a model for other high-risk surgeries, where complex vascular tumors must be removed without catastrophic bleeding. And as imaging and AI-assisted surgical planning evolve, FENCY ligation could become even more precise and adaptable.

Unfortunately, the FENCY ligation method takes time, sometimes hours of meticulous stitching, and requires highly trained hands. In certain areas, like near the facial nerve, the risk of temporary paralysis or gland swelling must be managed with great care.

Still, the implications are exciting. For patients living with NF1, this research offers something far more valuable than a new surgical technique, it offers hope. Hope that giant tumors no longer have to mean giant risks. Hope that a disfiguring disease can be met not with resignation, but with precision, creativity, and compassion.

If you want to learn more, read the original article titled "An innovative resection of giant neurofibromas." on Chinese Journal of Plastic and Reconstructive Surgery at http://dx.doi.org/10.1016/j.cjprs.2025.06.003.