PET Scans Prevent Unnecessary Surgery in NSCLC

AMSTERDAM—The use of positron-emission tomography (PET) scans to stage patients with non–small-cell lung cancer (NSCLC) could prevent as many as one in five unnecessary thoracotomies, according to research presented at the ASCO meeting.

As many as 50% of patients with NSCLC undergo surgery unnecessarily, Dutch investigators pointed out, for reasons such as disease metastases unknown at time of surgery. The multi-institutional study tested the ability of PET scans to accurately determine the stage of disease and to prevent “futile thoracotomies.”

Thoracotomy was considered futile if disease was found to be benign or far advanced at the time of surgery, or if patients had recurrent disease or died within 1 year of surgery.

Adding PET to Work-up

Prior to mediastinoscopy or thoracotomy, 96 patients with potentially resectable NSCLC were randomized to a conventional work-up, and 92 received a conventional work-up plus PET scan. Most patients underwent mediastinoscopy, but some with small tumors went directly to surgery.

“We found that the number of futile thoracotomies was halved when we included PET in the workup,” reported Harm van Tinteren, MD, from the Comprehensive Cancer Center, Amsterdam. “In a large number of patients, noncurative thoracotomies were avoided. In short, PET scans stage tumors more accurately than CT scans.”

Futile thoracotomies were noted in 39 of 96 patients in the conventional work-up group (41%), and 19 of 92 patients in the PET arm (21%), for a statistically significant relative reduction of 51%, he reported.

The reduction was evident in three different phases. Preoperatively, the major contrast was seen in the occurrence of upstaging due to PET: 25 patients were upstaged in the PET arm, vs 11 in the conventional arm; 7 unexpected distant metastases and 18 positive lymph nodes were seen on PET and later confirmed. “This might suggest a better yield,” Dr. van Tinteren commented.

Surgery itself proved more futile in the conventional arm than in the PET arm, due either to extensive disease that was considered inoperable (12 vs 6) or to the presence of benign lesions (7 vs 2). There was no difference in the number of nonfutile thoracotomies according to group, he further reported.

Fewer Relapses With PET

Because PET scans more accurately determined which patients would benefit from surgery, only 4 patients in the PET group relapsed after surgery, compared with 14 patients in the conventional work-up group.

Furthermore, the study included a cost analysis, which showed that the cost of using PET—while more expensive up front—was “a wash” because of the savings realized by reducing unnecessary surgery, Dr. van Tinteren added. “We concluded that PET reduces futile thoracotomies by 50% without additional cost.”

At a press conference, it was pointed out that a Southwest Oncology Group (SWOG) survey found that 85% of group investigators currently use PET scans. SWOG concluded that PET scanning is becoming rapidly available in the United States, even to community physicians.

A national lung cancer trial is now assessing the usefulness of PET scanning for accurate restaging after chemotherapy but prior to surgery. While PET scanning has become standard for the staging of NSCLC, its role in restaging is still unsettled.