Multidisciplinary Approach Improves Staging of NSCLC

SEATTLE-A multidisciplinaryapproach may improve clinicalstaging (cTNM) in patients withnon-small-cell lung cancer (NSCLC),Ana Rocha, MD, said at a poster sessionof the 99th International Conferenceof the American Thoracic Society(B111, poster B14). "Clinical staging isnot perfect and has been shown to beinaccurate more than 50% of the time,"Dr. Rocha said in an interview withONI. "We wanted to show that wecould do a better job with a multidisciplinaryapproach."Accurate clinical staging of NSCLCdepends on a thorough clinical evaluationand interpretation of chest CTimaging, she said. However, there areclear limitations to the accuracy of achest CT, and combined surgical andpathologic evaluations (pTNM) havebeen found to be more accurate indefining disease stage. Previous trialshave shown discordance betweencTNM and pTNM in 53% of cases."We had a lower incidence of upstaging(35%) than what is quoted inthe literature," said Dr. Rocha, a fellowin the Department of Medicine, Divisionof Pulmonary Diseases/CriticalCare Medicine, Duke UniversitySchool of Medicine. "And in a novelfinding, we found that tumors locatedon the lower lobes were more likely tobe upstaged."In a prospective cohort study, 160male patients were diagnosed with clinicalstage I/II NSCLC between September1997 and April 2002. Half ofthe patients had squamous cell cancers,56 (35%) had adenocarcinomas,14 (8.8%) had large-cell carcinomas,and 10 (6.2%) had cancers that werenot subtyped. Of 160 patients, 109(68.1%) underwent operative resectionand had pTNM determined atthat time by lymph node dissection.The cTNM corresponded to pTNMin 70 of the 109 patients (64.2%); onlyone subject was downstaged, and 38(34.9%) were upstaged. Unsuspectednodal involvement (N stage) was responsiblefor upstaging in 18 patients(47%), more extensive tumor stage(T stage) in 15 patients (40%), andboth N stage and T stage in 3 patients(8%). Metastatic disease was found in2 patients (5%).Tumors in the upper lobes weremore common (78% of cases), butthose located in the lower lobes weresignificantly more likely to be upstagedfollowing surgery (58.3% vs 28.2%,P < .006). Location in the lower lobeswas the only significant associationwith upstaging, and no association wasfound with factors such as age, smokinghistory, weight loss, tumor size,and histology."That was a robust finding evenwhen controlling for other factors,"Dr. Rocha said, "and we have to seewhat the mechanisms are for thisfinding." It is very important forclinicians to pay special attention tothese lower-lobe tumors, she added,and to be more aware that they havea greater propensity of being higherT stage.Future research may involve lookingat gene expression on lower-lobetumors as a possible explanation ofwhy they are more aggressive and havea higher rate of upstaging, she said."As a multidisciplinary group, involvingpulmonary, pathology, oncology,surgery, and radiology, we did abetter job of selecting the patientswho went on to have a surgical resection,"Dr. Rocha concluded. "Themultidisciplinary approach had abetter predictive value in terms ofselecting the population that wouldmost benefit from having surgery. Itis a major surgery, and we don't wantto send patients for surgery if theywill not have a good result."