Impact of inappropriate lymphadenectomy on lung metastasectomy for patients with metastatic colorectal cancer

Purpose To evaluate the characteristics of lymph node assessment in the Spanish Colorectal Metastasectomy Registry (GECMP-CCR) and to analyze and compare the survival of patients with pathological absence or presence of lymph node metastases (LNM) with the survival of those with uncertain lymph node status (uLNs). Methods A total of 522 patients with lung metastases from colorectal carcinoma were prospectively registered from 2008 to 2010. To confirm the pathologic absence of LNM, systematic nodal dissection or systematic sampling was required, or the lymph node status was coded as uncertain. Disease-specific survival and disease-free survival were calculated by the Kaplan-Meier method with the log-rank test for comparisons. Results Lymphadenectomy was performed in 250 (48 %) patients. LNM was found in 25 (10 %) of the patients who had lymph node assessment done. The 3- and 5-year disease-specific survival rates according to lymph node status were 73.5 and 58.3 % in the absence of LNM, 50.5 and 24.8 % when LNM was confirmed, and 69 and 44 % for those with uLNs, respectively (p = 0.006). Conclusions The presence of LNM and uLNs is associated with an increased risk of death. The association of nodal assessment at the time of metastasectomy to identify LNM helps us to refine the postoperative prognosis; therefore, its impact should be properly studied in a prospective clinical trial.