OBJECTIVETo analyze the impact of meticulousness of pathologists on the lymph node harvest after radical resection of invasive rectal carcinoma.

METHODSFrom January 2008 to May 2009, the clinical data of rectal cancer patients undergone operation were reviewed retrospectively. After multidisciplinary cooperation on rectal cancer, a new rule was applied to request the pathologists to find no less than 15 nodes in single colorectal specimen from January 2009. Patients were divided into two groups (2008 group and 2009 group) and the node harvest numbers were compared. Excluded criteria were recurrent colorectal tumor, Tis tumor, R(1) or R(2) resection, tumor resection transanally or endoscopically, the cases enrolled in other prospective research, synchronous diseases affecting the surgical procedure for the rectal cancer (familial adenomatous polyposis, synchronous colorectal carcinoma) and rectal cancer receiving neoadjuvant chemoradiation. Statistical analysis was performed using One-Sample Kolmogorov- Smirnov test, Mann-Whitney test, Independent-Samples T test and Chi-Square test(SPSS 15.0).

RESULTSA total of 232 patients were identified, including 76 cases in the 2009 group and 156 cases in 2008 group. The lymph node retrieval in the 2009 group was significantly more than that in 2008 group (16.0+/-0.3 vs 11.4+/-0.3, P<0.01). A significantly higher percentage of patients was found in 2009 group with a lymph node harvest equal to or more than 12 nodes (72/76 vs 71/156, P<0.01). There were no significant differences in gender (46/76 vs 86/156, P=0.436), age (58.1+/-1.3 vs 59.2+/-1.1, P=0.527), distance from tumor to anal verge (7.4+/-0.4 vs 7.1+/-0.3, P=0.761), proportion of sphincter-sparing surgery (67/76 vs 140/156, P=0.715), ratio of well and moderate differentiated tumors (68/76 vs 125/156, P=0.074) and overall TNM stage (P=0.167) between the two groups.

CONCLUSIONSThe lymph node harvest in 2009 group is significantly more than that in 2008 group. The good performance of pathologists could produce adequate number of lymph nodes for rectal cancer without neoadjuvant chemoradiation.