First-in-kind NSCLC diagnostic tech may help improve patient outcomes

At the 56th Annual Meeting of The Society of Thoracic Surgeons, researchers presented a tumor-highlighting technology—OTL38—that radically improves the visualization of lung cancer tissue. This groundbreaking diagnostic tool could help physicians identify and resect more tumor cells than ever before. 

“Near-infrared imaging with OTL38 may be a powerful tool to help surgeons significantly improve the quality of lung cancer surgery by more clearly identifying tumors and allowing the surgeon to better see and completely remove them—one of the most vital components in the overall care of patients with this disease,” stated author Inderpal S. Sarkaria, MD, University of Pittsburgh Medical Center, Pittsburgh, PA. 

“Use of advanced near-infrared imaging techniques such as OTL38 may provide surgeons with powerful tools to improve the quality of lung cancer operations by better identifying small, hard-to-find tumors, finding previously undetected cancers at the time of surgery, and better assessing if the entire tumor has been removed,” he added.

Although surgery is the best chance at cure for those with early-stage NSCLC, 30% to 50% of those with the disease go on to experience recurrence, which is often due to clusters of undetected cancer cells. Therefore, complete resection of macroscopic and microscopic lesions is imperative.

X-rays, MRI, CT scans, PET scans, or ultrasound are typically used to gauge the size and location of cancer lesions before surgery. These modalities, however, are rarely used during surgery. 

OTL38 is believed to be the first targeted fluorescent marker that may be useful during surgery. In real- time, while the surgeon is operating, OTL38 detects cancerous tissue not previously seen on preoperative scans. Complete resection of cancerous tissue during surgery helps boost survival by avoiding cancer relapse and obviating any need for additional surgeries. Moreover, in many cases, preoperative biopsy is neither practical nor feasible, with intraoperative identification being the best option for identification of cancerous nodules.

In the current phase 2 clinical trial, Dr. Sarkaria and colleagues from six institutions—including the University of Pennsylvania, Harvard University, Cleveland Clinic, and MD Anderson—selected 92 patients with lung lesions who were scheduled to receive surgery for non-small cell lung cancer (NSCLC). They administered an intravenous dose of OTL38 to each patient before resection. OTL38 consists of near-infrared dye plus a targeting molecule, which binds to cancer cell receptors that are folic-acid based and glows after exposure with a specialized endoscope. This novel technology identifies otherwise hard-to-spot lesions.

The researchers made assessments in three phases. During the first phase (“lung inspection”), they used molecular imaging to identify 10 additional cancers—all of which were missed during visual inspection and palpation—in 8% of the study population. During the second phase (“lung resection”), they found that OTL38 allowed for localization of the lesions not found in 12% of the study participants. During the third phase (“specimen check”), they found that all margins were clear, and further examined resected specimens via molecular imaging. Notably, inadequate margins were found in 9% of patients. In total, OTL38 imaging improved outcomes in 26% of patients.  

“OTL38 is the first technique that is specific to imaging adenocarcinomas of the lung, which is one of the most common types of invasive lung cancer, making it unique and clinically useful in this respect,” said Dr. Sarkaria. “Localization of tumors, identification of occult tumors, and immediate tumor margin assessment during surgery for adenocarcinomas of the lung were significantly improved with the use of this technology.”   

The timing of this diagnostic innovation is, indeed, opportune, with lung screening and increased utilization of CT scans allowing cardiothoracic surgeons to visual small or undefined nodules. To boot, OTL38 may avoid the need for thoracotomy by offering a minimally invasive means to identify such nodules.