Lung CAD Earning a Spot in Day-to-Day Practice

Fueled by clinical studies, integration with IT and reimbursement

The integration of computer-aided detection (CAD) software into the day-to-day practice of radiology has witnessed the enthusiastic adoption of the applications for some clinical indications. Mammography CAD, which was first greeted with skepticism and suspicion by radiologists, has since enjoyed a groundswell of support. Lung CAD, thanks to diligent efforts by early adopters, is showing signs that it may be the next area of medicine to embrace widespread utilization of this technology.

According to the American Cancer Society, lung cancer is difficult to treat because it is rarely caught in its earliest stages—when treatment options are most effective. As such, only 16 percent of patients diagnosed with lung cancer have a 50 percent chance of living beyond five years.

Given those statistics, a CAD application that can improve the diagnostic certainty of a primary evaluation for lung cancer and automatically track changes in nodule size during follow-up studies should be warmly welcomed by the clinical community. Although the technology was approved by the FDA in 2001 for chest radiography, and in 2004 for CT, it has not yet achieved the support and infiltration mammography CAD enjoys.

However, an ever-growing bibliography of peer-reviewed scientific journal articles demonstrating its efficacy, the integration of applications into enterprise healthcare systems, and reimbursement for its use by more payors signals that the technology may at last be poised for mainstream adoption.

Radiography CAD gets results

A recent prospective study published in Academic Radiology (May 2008) conducted by Edwin J.R. van Beek, MD, PhD, and colleagues in the department of radiology at the Carver College of Medicine, University of Iowa in Iowa City, Iowa, provides strong support for lung CAD utilization.

Chest radiography was performed using a Siemens Medical Solutions DR unit on 324 patients for surveillance of metastatic disease with known malignancy. Their exams were interpreted by experienced pulmonary radiologists via the PACS at the facility, and utilized IQQA Chest CAD software from EDDA Technology.

The study evaluated the sensitivity and specificity of the radiologists’ diagnostic interpretations with and without the use of CAD. For studies without the assistance of CAD, the radiologists’ diagnostic performance showed a sensitivity of 63.6 percent and a specificity of 98.1 percent. However, with the addition of CAD, the radiologists demonstrated a specificity of 92.7 percent and a specificity of 96.2 percent.

“This benefit [lung CAD utilization] might have important implications, related to the identification of patients for whom therapy is failing or in the identification of early metastatic disease where different treatment regimens are still available,” the authors wrote. “Both observations should result in important management decisions, thus improving overall patient care.”

Approximately 160 miles to the northwest of the Carver College of Medicine is Hamilton Hospital, a 25-bed facility serving the rural area of Webster City, Iowa. Charles N. Heggen, MD, a radiologist with the group Iowa Radiology, has used OnGuard lung CAD technology from Riverain Medical at the facility since April 2007.

His practice decided to adopt lung CAD technology based on its success with CAD for mammography and an ongoing interest by the physicians in improving lung cancer screening for its patient population.

“All AP [anterior/posterior] or PA [posterior/anterior] chest x-rays on patients 35 years of age and older are processed with CAD,” Heggen says. “The CAD image is viewed each time a chest x-ray is reviewed. This practice has directed the interpreting radiologist’s attention toward some areas on the image that needed a closer look.”

Iowa Radiology marketed its use of lung CAD, both to its referring physician base as well as to the public via print and radio advertising, and found favorable reaction to the technology from both groups.

The group has worked diligently to ensure reimbursement for the application, educating its payors about CPT codes for the technology.

“Initially, our Medicare local fiscal intermediary denied the claims because they did not recognize the CPT codes,” he noted. “Following educational work with them, they are now covering this service. Most of our other private payors are covering the service as well.”

CT CAD: Workflow and diagnostic benefits

Thousands of miles from Iowa, Dag Wormanns, MD, medical director and head of the department of radiology at ELK Berlin Chest Hospital in Germany has found LMS lung CT lung CAD from Median Technologies to be a benefit to his practice.

Radiologists at the facility routinely use the CAD functionality prior to resection of lung metastases to ensure that the surgeon is aware of all lung lesions to be resected. In addition, he has found the tracking capabilities of the software to be a welcome addition to the department’s workflow.

“It allows for convenient comparison of previous and current examination and alleviates tracking of tumorous lesions over time during the course of treatment,” he said. “It is capable of speeding up clinical demonstrations due to the bookmarking of lesions and anatomic synchronization of previous and current examination.”

Peter Herzog, MD, a fellow of radiology at Klinikum Grosshadern, University of Munich, Germany, has found the deployment of syngo Lung CAD (CT lung CAD) from Siemens Medical Solutions has increased the diagnostic certainty of chest exams at his facility in the nine months since its deployment.

“Approximately 60,000 cases have been processed by CAD and it has helped a lot, especially in scans that were not originally performed to rule out malignancy in the chest,” he noted. “A considerable number of clinically actionable findings were obtained.”