COMPARISON OF IMAGING TNM [(I)TNM] AND PATHOLOGICAL TNM [PTNM] IN STAGING OF BRONCHOGENIC-CARCINOMA

Objective: Precise tumor (T) and nodal N staging is imperative in non- small cell Inn cancer (NSCLC) as it determines subsequent treatment, c ertainly when considering neoadjuvant treatment for stage IIIA or IIIB disease. To determine the accuracy of present-day computed tomographi c (CT) scanning a prospective study was performed comparing imaging TN M [(i)TNM] and pathological TNM [pTNM]. Methods: In 74 patients with N SCLC without distant metastases (i)TNM was determined oil CT findings. The TNM system advocated by the American Joint Committee on Cancer wa s used. All patients underwent cervical mediastinoscopy. When superior mediastinal nodes were negative this was followed by thoracotomy and pathological examination of the resected specimen and lymph nodes to d etermine pTNM. Results: The agreement between (I)TNM and pTNM was only 35.1%. The primary tumor (T) was correctly staged in 54.1%, overstage d in 27.0% and understaged in 18.9% of the patients. Invasion of chest wall, pericardium and of major mediastinal structures (T3, T4) was no t reliably detected by CT scan. Sensitivity and specificity of CT rega rding hilar and mediastinal lymph node staging were 48.3 and 53.3%, po sitive and negative predictive value 40 and 61.1% and its overall accu racy 51.4%. The nodal (N) factor was correctly determined by CT scan i n 35.1%, overstaged in 44.6%, and understaged in 20.3% of the patients . Conclusions: Even with present-day CT scanners (i)TNM provides no ac curate staging and routine mediastinoscopy is necessary for precise me diastinal lymph node staging. Likewise, (i)T3 and (i)T4 determinations are unreliable and should not contraindicate thoracotomy. (C) 1997 El sevier Science B.V.