At the dawn of the third decade of the century, the concept of vision as it applies to both practical application and imagination seems fitting for Penn Otorhinolaryngology – Head and Neck Surgery (Penn ENT).
Trans oral robotic surgery (TORS), invented at Penn ENT in the first decade of the century was created, in part, to permit a greater field of vision for surgeons performing minimally invasive surgeries of the head and neck. Today, a second innovation developed at Penn, TumorGlow, is allowing Penn ENT surgeons to visualize and interpret tumor margins to better ensure complete resection. Both innovations owe their origin to the commitment, perception and intuition of the departments' surgeons.
Karthik Rajasekaran, MD, FACS, is in a unique position to appreciate both the recent history of Penn ENT and the challenges of head and neck surgery. A head and neck oncologic and reconstructive surgeon, Dr. Rajasekaran is Co-Director of the Head and Neck Oncologic and Reconstructive Fellowship, as well as Director of Facial Trauma and Director of Quality Improvement for Penn ENT. He recently spoke about how advances in head and neck surgery, including TORS and TumorGlow, are moving the field forward.
Tumors that involve the head and neck typically affect structures that are crucial for speech and swallowing. The goal of any surgery is to maximize oncologic control and minimize surgical resection. Often times, the decisions on where to make incisions and how much tissue to cut are based on tactile perception and with the use of preoperative scans like CTs and MRIs. "This isn't a perfect science, and though we are able to obtain excellent oncologic and functional outcomes, there is always room to enhance the care we are able to provide our patients," says Dr. Rajasekaran.
Enter TumorGlow.
Developed almost a decade ago at Penn Medicine, TumorGlow is an intraoperative, near-infrared fluorescence imaging modality that does just what its name suggests — it makes tumor tissues glow, enhancing the identification of ideal margins for resection. First applied in lung cancers, TumorGlow and its techniques have been adapted at Penn for neurosurgery, abdominal surgery, and other areas. In obstetrics and gynecological surgery it was recently accorded FDA approval for ovarian cancer.
In head and neck surgery at Penn ENT, TumorGlow is being used for two important initiatives. The first involves enhancing surgical accuracy in tumor margin resection, an effort, Dr. Rajasekaran says, that is allowing surgeons to refine their surgical technique. Still in early investigations in this context, he adds, the data looks very good, and the value of the technology is evident.
The second research initiative for TumorGlow at Penn ENT involves discovery for tumors of unknown primary.
"Head and neck surgery patients often present with a cancerous lymph node that appears as a neck mass," says Dr. Rajasekaran. "As surgeons, we know that the origin of the cancer is in either the tonsil or the base of the tongue, but these primary tumors are often so small, only one to two millimeters, that PET and CAT scans and MRIs can't detect them. The tissue all looks the same."
In this instance, he continues, TumorGlow allows surgeons to find the primary, and potentially limit the amount of surgery needed for resection, a capability no other imaging modality has at this time.
Differentiators
While surgical volume and experience have long been known to have an equation with positive outcomes, [1-4] head and neck tumors can present a conundrum in their rarity.
"Head and neck cancers comprise only 5 percent of all cancers," says Dr. Rajasekaran. "So what you have are very serious cancers in extremely difficult locations that can have functional and cosmetic effects - but that aren't especially common."
This dearth can mean that these cancers, even at high-volume centers, can present issues for surgeon experience.
"I did my residency at an institution with a very high volume for surgery," Dr. Rajasekaran recalls, "but there were cancers that I seldom encountered there, though I see them relatively often here."
That Penn ENT has one of the largest surgical volumes in the country today can be attributed, in part, Dr. Rajasekaran says, to TORS.
"I did my Fellowship here because I wanted to learn TORS at the source," he says. Dr. Rajasekaran was not alone. In fact, during the early years of TORS, hospitals and medical centers across the country sent surgeons to Penn to learn robotic head and neck surgery, and in so doing created a conduit for patient referrals.
"This large volume has allowed us to really push the boundaries and acquire the experience that's needed to gain proficiency in surgery," he says, adding that TumorGlow has had a part recently in further refining surgical acumen.
"Experience helps a great deal," he observes. "But there's always room for improvement in surgical technique, and this is a part of what TumorGlow allows us to do."
Clinical Trials
Just as TORS was defined through a series of clinical trials, studies are underway at Penn ENT to clarify the applications for TumorGlow. The Phase 2a ONCO-NANO trial, for example, involves evaluating the safety, timing and performance of TumorGlow for the detection of cancers in patients with solid tumors undergoing routine surgery. Grant applications are in submission to study TumorGlow in head and neck surgery, and investigator-initiated studies are in the works.
A further consideration at Penn ENT addresses the needs of patients confronting potentially disfiguring surgeries.
"Our interest today is not only to cure these cancers, but to do so in a way that preserves the quality of life of our patients," Dr. Rajasekaran says. "We want our patents to be able to go out and eat dinner in public. So we are now administering surveys to assess these metrics, as well as functionality. And from these surveys, we're trying to figure out how to improve and enhance patient quality of life."
TumorGlow has a role in QOL, as well, Dr. Rajasekaran concludes: "If you can cut less and preserve more normal tissue, intuitively, you'll see better cosmetic and functional outcomes for people who might otherwise have had much more morbid surgery."
References
- HPB (Oxford). 2021 Nov 1;S1365-182X(21)01669-5. doi:10.1016/j.hpb.2021.10.015.
- Scand J Gastroenterol.2021 Dec 6;1-5. doi: 10.1080/00365521. 2021.2012592.
- Eur J Cardiothorac Surg. 2021 Nov 29;ezab490. doi:10.1093/ejcts/ezab490.
- N Engl J Med. 2003 Nov 27;349(22):2117-27. doi:10.1056/NEJMsa035205.