RELEVANCE OF REGIONAL LYMPHATIC TUMOR-CEL L DISSEMINATION IN PATIENTSWITH RESECTABLE NON-SMALL-CELL LUNG-CANCER - RESULTS OF A PROSPECTIVE-STUDY

Encountering the high incidence of tumor recurrences in patients with apparently resectable nonsmall cell lung cancer it has to be assumed t hat in many patients already at the time of surgery a tumor cell disse mination has occurred, which is underestimated by current staging proc edures. We therefore conducted a prospective study to assess the frequ ency and prognostic significance of a nodal tumor cell dissemination b y using an immunohistochemical assay. Disseminated epithelial cells we re demonstrated in 35 (6.2 %) out of 565 lymph nodes staged as tumor f ree by conventional histopathology and in 27 (21.6 %) out of 125 patie nts, respectively. In pNO patients disseminated tumor cells were detec ted in 11/70 (15.7 %) cases. In patients staged as pN1 and pN2 by conv entional histopathology a tumor cell dissemination to additional lymph nodes was demonstrated by immunhistochemistry in 4/25 (16.0 %) and in 12/30 (40.0 %) patients, respectively (p = 0.019). Independent from t umor staging univariate survival analysis showed that the detection of a nodal tumor cell dissemination was associated with a reduced diseas e-free survival (p < 0.001). Multivariate analysis demonstrated that t he detection of such cells is an independent prognostic parameter (p = 0.005). In conclusion, the use of immunohistochemistry enables to ide ntify many patients with a widespread regional tumor cell disseminatio n at the time of surgery. This finding could represent a new criterion for an adjuvant therapeutic regime.