Early-stage lung cancer

November 23, 2015

Kemp Kernstine, M.D., Ph.D., Chief of UT Southwestern’s Division of Thoracic Surgery, is one of the world’s foremost authorities on video-assisted thoracic surgeries (VATS), having performed hundreds of the minimally invasive procedures. At UT Southwestern, about 85 percent of thoracic surgery patients have a minimally invasive procedure— even if their disease is locally advanced.

Minimally invasive techniques, dedicated surgeons characterize surgical treatments

The most advanced minimally invasive surgical techniques, used routinely at UT Southwestern to resect early-stage lung cancers, are sparing patients much of the pain and debility that can accompany open thoracotomy.

Dr. Kemp Kernstine, Chief of UT Southwestern’s Division of Thoracic Surgery, has been on the leading edge of this paradigm shift in lung cancer resection. In 1992, Dr. Kernstine and a colleague performed one of the earliest video-assisted lobectomies, a minimally invasive procedure, in the Northeast. He’s done hundreds of video-assisted thoracic surgeries (VATS) since and 10 years later became an early developer of robotic lobectomy techniques.

“With VATS, there were aspects of efficiency and detail that could be even better, so when robotics came along, it just made sense,” he says.

Patients undergoing robotic VATS spend less time in surgery than with open thoracotomy, while blood loss and infection risk potentially are reduced. Patients are typically home in three days, back to work in a couple of weeks, and often off pain medication within about a week, Dr. Kernstine says.

At many institutions, lung cancers are resected by cardiothoracic surgeons whose caseload is dominated by heart procedures, says medical oncologist Dr. Jonathan Dowell, who specializes in lung cancer and mesothelioma. But patients at UT Southwestern benefit from the vast experience of dedicated thoracic surgeons—Dr. Kernstine and Dr. Scott Reznik. “That’s a key difference,” Dr. Dowell says.

The thoracic surgery team performs about 150 surgeries for thoracic malignancies each year at UT Southwestern, about 100 more at Parkland Memorial Hospital, and 100 at the Dallas VA Medical Center.

At UT Southwestern, roughly 85 percent of thoracic surgical patients have a minimally invasive procedure—thoracoscopic, robotic, or a combination—even if their disease is locally advanced. By contrast, nationwide only about half of thoracic surgeons in a recent survey were performing lobectomies using VATS or robotic VATS— and among them, only about one-fifth used VATS in 80 percent or more of cases (Cao, Chest, 2014).

Of surgeons in the survey who never performed a VATS lobectomy, many cited a lack of opportunities to learn the procedure. Dr. Kernstine is spearheading efforts at UT Southwestern to change that.

“We really perfected the details of the robotic procedure and are now teaching it regularly to our trainees,” he says. “They are removing lobes in one-third the time it would take to do an open procedure, learning how to make it an efficient and extraordinarily safe process.” Dr. Kernstine also goes to other hospitals, and even abroad, to train surgeons, while many come to UT Southwestern to observe and learn.

Patients with early-stage cancers also benefit from UT Southwestern’s academic research environment. Their cases frequently are presented at Simmons Cancer Center’s multidisciplinary lung tumor conference (see multidisciplinary approach to care), at which a range of lung cancer experts develop individualized treatment strategies. “Often there are questions, if it’s a marginally resectable tumor, about whether the patient should receive chemotherapy and/or radiation before surgery to improve the likelihood of a successful resection,” Dr. Dowell says. Resected tumor tissue is subjected to a rigorous molecular analysis to inform further treatment decisions, and with patients’ consent the tissue is also used for research.

Important research questions include the optimal use of molecularly targeted therapies in early-stage lung cancer, notes medical oncologist Dr. David Gerber. A new, five-year study that Dr. Gerber co-chairs, called ALCHEMIST, aims to help. Up to 8,000 patients nationwide will be enrolled in the trial, in which resected lung tumor tissue will be checked for dozens of molecular alterations, with targeted therapies used in certain cases. Other research aims to determine whether patients can benefit from new therapies given before surgery.

“What we need to remember,” Dr. Gerber says, “is that even stage I lung cancer has survival rates that could be markedly improved.”

Radiotherapy: Leading-edge tools to supplant—and supplement—surgery Pioneering radiotherapy research at Simmons Cancer Center has opened the door to a potential cure for early-stage lung cancer patients too frail to undergo surgery. Such patients might have COPD or heart or renal issues that simply make surgery too risky.

Four specialist radiation therapy physicians in the Department of Radiation Oncology focus on lung cancer, a level of expertise rare in most centers. “They are innovators,” Department Chair Dr. Hak Choy says of his colleagues, noting that the research on inoperable patients, using stereotactic ablative radiotherapy (SABR), has established UT Southwestern as the global expert in the field.

Each year, stage I non-small cell lung cancer is diagnosed in about 25,000 U.S. patients, and more than 5,000 of them are medically inoperable, says radiation oncologist Dr. Robert Timmerman. At the three-year mark, Dr. Timmerman and his colleagues found that SABR (also known as SBRT) eliminated the primary tumor in 98 percent of such patients and roughly doubled survival rates, to about 60 percent, compared with the previous usual care. “That changed the standard of care for those patients,” he says.

Now, after seven years of follow-up, high rates of tumor control have persisted, and worries about a surge of late toxic events have proved unfounded. “What we’re proud of is the fact that SABR is now used worldwide,” Dr. Timmerman says, adding that UT Southwestern has by far the most experience with the therapy (he estimates he personally has treated around 1,000 patients). “We’ve trained hundreds of physicians, physicists, and dosimetrists across the U.S. and around the world.”

Patients benefit from the vast experience of UT Southwestern’s thoracic surgeons, who, as a team, have perfected the details of robotic procedures and are now teaching the art to other surgeons, at home and abroad.

A key question soon to be addressed is whether—in borderline operable, early-stage lung cancer patients—SABR is equivalent to or better than surgery with respect to tumor control, survival, and toxicity. “We think SABR will be quite competitive, but we’ve never had a head-to-head study with surgery to address these questions in such a patient population,” says radiation oncologist Dr. Puneeth Iyengar. UT Southwestern researchers hope to lead a nationwide, randomized phase III trial enrolling about 600 such patients to answer that question.

Meanwhile, along with chemotherapy, radiotherapy remains an important treatment for patients whose cancers are revealed after surgery to be more extensive than pre-surgical evaluation indicated. And to further help prevent recurrence, UT Southwestern is poised to begin offering intraoperative brachytherapy, where the tumor bed is treated with special applicators or radioactive seeds at the time of surgery. Another technique is endobronchial brachytherapy, used sometimes to treat the surgical margin after a large lobar resection or pneumonectomy, says brachytherapy specialist Dr. Michael Folkert.

As for the future, the department’s radiation oncologists are exploring the power of SABR in metastatic lung cancer (see late-stage lung cancer). And they are aiming to develop SABR and other radiotherapy procedures using protons instead of photons—lowering dose to healthy tissues—once a new proton therapy center opens in 2017. Research by UT Southwestern radiation oncologist Dr. Ken Westover and others has shown that protons can deliver SABR to lung cancer patients who are even more frail than those who typically receive the therapy. “If a patient has very poor lung function, if the tumor is in a tricky location, or if patients have sensitive implantable devices like a pacemaker, protons can give you a very sharp dose gradient, allowing you to treat these otherwise untreatable patients,” he says.

The university already is on the leading edge in its technical ability to precisely target tumors while sparing normal tissue. Most radiation oncology facilities have just one or two of the multimillion-dollar machines used to treat cancer; UT Southwestern has a toolbox of nine, all with the latest imaging capabilities, and can choose the optimal one for each individual case.

“We reinvest our resources to continually update to the latest technology for patient care,” Dr. Choy says. “That’s our drug; that’s our knife.”