Finding the Unknown Primary in Head & Neck Cancer
In mid-summer 2010, 46-year-old Houstonian Paul Wyett found a found a small lump on his neck that he thought was an ingrown hair. “It swelled up and then went away but never completely disappeared,” he says.
His primary care physician suspected a nerve fiber tumor and referred him to an otolaryngologist, who did a needle biopsy that produced inconclusive results. “But we learned that the tumor was touching Paul’s carotid artery and invading the jugular vein, neither of which sounded good to us,” says his wife Adrienne Leigh.
Wyett underwent resection of the neck mass, and the final pathology report showed that the tumor was squamous cell carcinoma. Based on the report, his physicians sent Wyett to Ron Karni, MD, an assistant professor in the Department of Otorhinolaryngology-Head and Neck Surgery at UTHealth and a board-certified otorhinolaryngologist at Memorial Hermann-Texas Medical Center.
During his initial consultation with Wyett, Dr. Karni learned that while his patient had evidence of squamous cell carcinoma of the neck, the primary site had not been identified. “Despite the accuracy of today’s imaging studies, an estimated 10 percent of head and neck cancers present to physicians without an identified primary site,” he says. “Paul’s office examination, which included endoscopy, did not reveal an obvious lesion, but on careful review of his CT and PET scans, I noticed a subtle abnormality in the region of his left tonsil and tongue base.”
The plan of care for oropharyngeal cancer is dependent on staging, and because most head and neck cancers present as late stage with metastasis, treatment includes chemotherapy and radiation therapy. “Patients with an unidentified primary site of malignancy in the mouth or throat face radiation therapy that includes all the mucosal membranes from the back of the nose to the chest,” Dr. Karni says. “Radiation therapy of this magnitude is often toxic and can produce severe mucositis, difficulty swallowing, throat pain and weight loss. But surgery and a lesser dose of radiation may be possible if we can locate the primary site.”
In reviewing treatment options with Wyett and his wife, Dr. Karni offered them an innovative solution to the problem of the unknown primary site: the use of the da Vinci Surgical System. Approved by the FDA in December 2009 for transoral robotic surgery (TORS) for resection of tumors of the tongue and throat, the da Vinci robot offers advantages beyond traditional surgical approaches to the throat, especially in the region of the tonsil and tongue base.
“Instead of having to divide the lower lip or divide the mandible in the midline, we can approach these tumors directly through the mouth,” Dr. Karni says. “The challenge in treating tumors of the neck transorally is to achieve adequate visualization of the tumor for resection despite the sharp angles between the oral cavity and pharynx. The robot’s camera allows us to see around structures such as the tongue, and provides a highly magnified three-dimensional view. In this case, I felt strongly that the da Vinci’s capabilities would allow me to locate Paul’s lesion and remove it.”
The Wyetts also felt good about the robotic-assisted option. “We had a high level of confidence in Dr. Karni,” Adrienne Leigh says. “He was very good about walking the fine line between making the treatment decision for us and educating us about all our options so that we could make our own informed decision. It was very much a collaborative approach. In the end we thought, ‘Why not take advantage of this innovation?’ We liked the doctor, and we liked the way the procedure was being outlined. It just seemed to fit.”
Dr. Karni took Wyett to the OR on September 10, 2010. Using the da Vinci robot, he was able to identify, within half an hour, a 4-millimeter ulcer in the inferior pole of the patient’s tonsil near the tongue base. Using a laser specifically adapted to the robotic arm, he removed the lesion, a tumor measuring 1.7 centimeters that was buried between the tonsil and tongue base, along with a negative margin of tissue surrounding it. He also used the robot to perform a neck dissection, removing lymph nodes in the left neck to contain the spread of cancer.
Wyett was able to eat immediately following surgery. “Because we were able to identify and remove the primary site, Paul is undergoing a lower dose of radiation focused on a smaller area of his neck,” Dr. Karni says. “This novel minimally invasive approach to oropharyngeal cancer is allowing patients who qualify for the surgery to speak, swallow and breathe immediately after the procedure with very few side effects.”
“Dr. Karni is definitely leading the pack when it comes to transoral robotic surgery,” says Etan Weinstock, MD, an assistant professor in the Department, who has pursued subspecialty training in head and neck surgical oncology with a fellowship at The University of Texas M. D. Anderson Cancer Center. “But as a technology applied to otorhinolaryngology, robotic-assisted surgery is still in its infancy. Our main goal as physicians is always to offer the patient the greatest chance of survival and the lowest possible treatment morbidity. For early-stage disease, survival is equivalent between surgery and chemotherapy/radiation. For late-stage disease, you have to do chemotherapy and radiation regardless. For patients with advanced disease, adding surgery may increase the risk of morbidity.”
More than 85 percent of cancers of the oropharynx are basal tongue cancers, usually squamous cell, Dr. Weinstock says. “But about 70 percent of patients who present with oropharyngeal cancers have stage 3 or stage 4 disease that has spread locally in the head and neck, and about 20 percent of them will develop distant metastases. The patients I’m seeing have very advanced oropharyngeal cancer. For these patients I recommend the gold-standard treatment protocol, which has a 30-year track record of success. With this protocol, the prognosis remains relatively good even with advanced disease. Stage 1 and some select stage 2 tumors may be amenable to robotic surgery, but in the event of advanced disease the patient will require the chemo-radiation protocol anyway.
“Ron is innovative, and robotics is a great tool,” he adds. “We still need more conclusive data on morbidity and survival rates following transoral robotic surgery.”
Dr. Karni points to emerging data in the literature on the efficacy of TORS for oropharyngeal cancer. “We’re just now beginning to report results showing that robotic surgery is producing good outcomes. It’s my belief that TORS is going to change the playing field between physicians and oropharyngeal cancer. It gives us another tool as surgeons and gives our patients a precise minimally invasive approach with few side effects.”
“The bottom line is that we can offer our patients the organ preservation protocol with chemotherapy and radiation, as well as minimally invasive endoscopic surgery and robotic-assisted surgery,” says Martin J. Citardi, MD, professor and chair of UTHealth Otorhinolaryngology and chief of otorhinolaryngology at Memorial Hermann-TMC. “Every patient’s cancer is different. We always ask ourselves, ‘What is my chance of curing this cancer? How can I produce the best outcome for the patient? What treatment will result in the fewest side effects for this particular patient?’ The treatment protocol we select is a function of staging, anatomy, pathology, the physician’s intuition based on experience and the wishes and comfort of the patient.”
Wyett finished his radiation therapy the week after Thanksgiving 2010. “From what we understand, Paul has a good prognosis,” his wife says. “The first problem is finding the primary site. The next question is can you resect to negative margins? Then it’s a matter of whether you can remove the lymph nodes. This particular cancer responds well to chemotherapy and radiation but it’s one of the toughest treatments to undergo. It’s been a lot for us to deal with.
“I will say that the attitude you go into treatment with really makes a difference,” she adds. “From the get-go Paul said, ‘The odds of getting cancer today are pretty high and apparently, this is my turn. We’ll get through it.’”
Dr. Karni’s clinical interests include general otorhinolaryngology, robotic-assisted and minimally invasive approaches to surgery, management of thyroid and parathyroid disorders including diagnostic ultrasonography, head and neck cancer, treatment of salivary gland disorders, surgery of the nose and paranasal sinuses, evaluation of voice and swallowing problems including transnasal esophagoscopy, and sleep medicine.