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Objective: To investigate the prevalence of lymph node metastases and long-term outcome as well as to determine prognosticators in patients undergoing systematic lymph node dissection and pulmonary metastasectomy of colorectal cancer. Methods: We retrospectively reviewed our prospective database of 165 patients with colorectal cancer undergoing pulmonary metastasectomy and systematic lymph node dissection with curative intent from 1999-2009. Results: The prevalence of lymph node metastases was 22.4%. Lymph node metastases were more often detected in case of rectal cancer (30,2% rectum vs. 11,6% colon, p= 0,005), segmentectomy/lobectomy for pulmonary metastasectomy (27,5% segmentectomy/ lobectomy vs. 12,5% wedge resection / laser resection, p= 0,031) and the number of metastases above 10 (45,5% number of metastases above 10 vs. 20,8% number of metastases 1-9, p= 0,071), respectively. Median survival for all patients was 64 months. Lymph node metastases were associated with inferior but promising survival (44 vs. 78 months, p= 0.03). Rectal cancer, M-status of the primary tumor, number of pulmonary metastasis and disease progression during pre-metastasectomy chemotherapy were independent significant prognosticators. No significance was found between the type of metastases, was it synchronous or metachronous lung and liver metastases (just lung 78 months, metachronous lunge and liver 74 months, synchronous lung and liver 63 months, p= 0,527). 66% of our resections were anatomic segmentectomy or lobectomy, neither wedge resection nor laser resection were possible in this cases. For this reason the growth of the metastases requests a lymph node dissection, because a segmentectomy and a lobectomy are just possible after dissecting the lymph nodes. Conclusions: Lymph node metastases are associated with inferior but promising long-term survival justifying aggressive pulmonary metastasectomy in selected patients. Systematic lymph node dissection should be recommended due to high prevalence of lymph node metastases in case of rectal cancer, required anatomic resections and multiple metastases. Rectal cancer, M-status of the primary tumor, number of pulmonary metastasis and disease progression during pre-metastasectomy chemotherapy were independent negative predictors of survival.