Lymph Node Evaluation as a predictor of survival after resection for colorectal cancer

Lymph Node Evaluation as a Predictor of Survival after Resection for Colorectal Cancer Giuseppe Pappalardo, MD, FACS Aldo Nunziale, MD Rome, Italy We read with great interest the article by Jan HWong and colleagues, “Lymph node counts as an indicator of quality at the hospital level in colorectal surgery.”1 If the number of lymph nodes evaluated after surgical resection of colorectal cancer (CRC) has a significant impact on survival, it represents an item frequently discussed in the last decades. There was no statistically significant difference in diseasespecific survival for N1 or N2 patients between 3 groups with median number of nodes examined, respectively, of 4, 8, 10 in Region 5 of the California Cancer Registry. These data contradict other reports, which demonstrated a dramatic impact of lymph node harvest on survival for both N1 and N2 positive disease.2 These findings in stage III disease could show an impact that transcends simple understaging and undertreatment in N negative patients with less than 12 examined nodes. At the present time, there is great confusion about lymph node counts as a predictor of survival and quality at the hospital level in CRC patients. Many factors can contribute to the difficulties in evaluating data regarding the relationships between lymph nodes and survival: the extent of lymphadenectomy, the number of nodes examined, the significance and the role of micrometastases, the ratio of positive to total nodes harvested, etc. We believe that one additional factor could be underestimated: the lack of standardization of specimen handling techniques. Should only palpable nodes be evaluated? Are fat-clearing techniques mandatory or optional? The lack of this standardization creates a bias that makes pathologic examination operator dependent. In other words, the same specimen can give different results on lymph nodes removed. Any effort to obtain a standardized pathologic examination should be made to improve results and analysis of quality in the treatment of CRC patients.