A Kinder Cut: Advances in Surgery for Head and Neck Cancer
Before the development of chemotherapy, radiation therapy, and targeted treatments for cancer, there was surgery. And today, the physical removal of cancerous tissue remains a cornerstone of treatment for most tumor types.
But cutting into the body comes with many risks, and it leaves its mark. In parallel with their colleagues working on the systemic treatment of cancer, academic surgeons have been performing research to improve the outcomes of surgical oncology, attempting to minimize damage, maximize effectiveness, and improve reconstruction of damaged tissue.
For example, for tumors at the base of the skull, "Traditionally…they would have to open up the face and even maybe remove part of the face to get at these tumors, or come in from above, opening up the skull and moving the brain aside," explains Dr. Carter Van Waes, chief of the Head and Neck Surgery Branch at the National Institute on Deafness and Other Communication Disorders. "It was successful in curing many patients or…palliating the disease, but the functional and aesthetic outcomes were short of what people desired."
The next surgical revolution came in the 1980s and 90s, with the rise of minimally invasive endoscopy applied to head and neck surgery. The endoscope allows surgeons to operate through existing openings, such as the nose and mouth, or through relatively small incisions, potentially reducing surgical morbidity.
Recently, the Southwest Oncology Group tested endoscopic transoral (through the mouth) surgery in a phase II clinical trial for patients with early-stage laryngeal cancer. Although the trial did not have a standard, open-surgery control group, says senior study investigator Dr. David Schuller from Ohio State University, "Subjectively we're seeing absolutely no difference in terms of survival outcomes, but certainly are impressed with the decreased morbidity, the decreased length of hospital stay, and the decrease of blood loss. So we're cautiously optimistic.
"If we could continue to use surgical modalities to help us with cytoreduction at the same time that we decrease morbidity - enabling the patients to move on quickly to nonsurgical adjuvant therapies - that's the hope," he continues. Investigators are now experimenting with robotics-assisted endoscopic surgery in the head and neck region, to assess its feasibility and potentially increased surgical precision in small physiologic spaces.
Putting the Pieces Back Together
Fortunately, reconstructive surgery for the head and neck region has also made great strides in the past 20 years. Before modern tissue transfer techniques became possible, simple skin and nonvascular bone grafts were used to close a remaining defect and prevent infection. But these techniques were not adequate to restore normal appearance, and in the case of bone grafts, were often reabsorbed by the body.
An important advance in surgical reconstruction came with the development of pedicled (attached) regional flap transfer, which allowed surgeons to cut a piece of tissue from a nearby structure (such as a chest muscle) and move it, still attached to its blood supply, to the site of the surgical defect.
Though a vast improvement over nonvascular grafts, this technique was limited to nearby donor tissue. Additionally, the flaps could have problems healing, particularly from tension caused by the attachment to the donor site or damage to the recipient site from radiation therapy. These problems were addressed by the development of free tissue transfer, in which microvascular surgeons remove a piece of muscle, bone, or both, from elsewhere in the body, along with the associated blood vessels, and reattach those blood vessels at the transplant site.
"More and more head and neck surgeons have become trained in microvascular techniques, and I think, once a critical mass of microvascular surgeons was available to perform these procedures and analyze the effect of these reconstructions - showing their superiority in many instances - that really allowed it to become standard [care]," explains Dr. Theodoros Teknos, chief of Head and Neck Oncologic Surgery at the University of Michigan.
Free-flap transfer can also be combined with dental and facial prosthetics, to include artificial ears, eyes, teeth, or other body parts and provide a more natural appearance for patients.
Looking to the future, says Dr. Teknos, "The next big phase in reconstruction is going to be tissue engineering." To avoid the donor-site damage that can be caused by harvesting muscle or bone for free-flap transfer, and to provide more personalized reconstructions, investigators are experimenting with growing custom bone, using adult stem cells, or protein or gene therapy.
Recently, investigators in Germany succeeded in growing a new jaw bone for a man who had undergone an extensive tumor surgery. The researchers filled a custom mesh cage with bone mineral blocks, bone marrow containing hematopoietic stem cells, and bone morphogenic protein and implanted it into the patient's back muscle, creating a new piece of custom-fitted bone with a healthy blood supply that they successfully transferred to the jaw.
For both future ablative and reconstructive advances, participation from all the associated specialties will remain essential. "Bringing together the thought leaders from all over the country, from all of the disciplines…not just the therapeutic, but also the rehabilitative and the quality-of-life expertise…I think that's what's going to accelerate the productivity in clinical research," concludes Dr. Schuller.