Negative Lymph Node Count is an Independent Impact Factor for Predicting the Specific Survival of Primary Duodenal Neoplasms under Surgical Procedures.

Abstract

The work aimed to assess the influence of negative lymph node numbers on specific survival of primary duodenal neoplasms under surgical procedures. This study focused on the primary duodenal neoplasm patients that have been registered in the "surveillance, epidemiology, and end results" (SEER). First, the important factors were screened by the Kaplan-Meier (Log-rank) in R and the Cox's proportional hazards regression model. Subsequently, a nomogram was established based on key proportional hazards including the negative lymph node count. Finally, the analysis of the specific survival by Kaplan-Meier (Log-rank) and X-Tile was performed to identify the cutoff values of negative lymph node numbers. There were 463 selected patients. Five impact factors were screened including the negative lymph node count (between 10 and 32), age (< 73), differentiation of cancers (well or moderate), primary tumors' invasion to tissues' superficial parts, no distant metastasis. The C-index of the nomogram in this paper was 0.74. The negative lymph node count and the other four factors were used for predicting the specific survival of primary duodenal neoplasms under surgical treatment, and the highest 2-year cancer's specific survival occurred when the negative lymph node numbers were 10 - 32. Besides, the nomogram in this paper proved to be more useful in predicting the survival effects than the traditional American Joint Committee on Cancer classifica-tion methods.