[The significance of regional lymphatic tumor cell dissemination in patients with resectable non-small cell bronchial carcinoma. Results of a prospective study].

Encountering the high incidence of tumor recurrences in patients with apparently resectable non-small cell lung cancer it has to be assumed that in many patients already at the time of surgery a tumor cell dissemination has occurred, which is underestimated by current staging procedures. We therefore conducted a prospective study to assess the frequency and prognostic significance of a nodal tumor cell dissemination by using an immunohistochemical assay. Disseminated epithelial cells were demonstrated in 35 (6.2%) out of 565 lymph nodes staged as tumor free by conventional histopathology and in 27 (21.6%) out of 125 patients, respectively. In pN0 patients disseminated tumor cells were detected in 11/70 (15.7%) cases. In patients staged as pN1 and pN2 by conventional histopathology a tumor cell dissemination to additional lymph nodes was demonstrated by immunohistochemistry in 4/25 (16.0%) and in 12/30 (40.0%) patients, respectively (p = 0.019). Independent from tumor staging univariate survival analysis showed that the detection of a nodal tumor cell dissemination was associated with a reduced disease-free survival (p < 0.001). Multivariate analysis demonstrated that the detection of such cells is an independent prognostic parameter (p = 0.005). In conclusion, the use of immunohistochemistry enables to identify many patients with a widespread regional tumor cell dissemination at the time of surgery. This finding could represent a new criterion for an adjuvant therapeutic regime.