Influence of Preoperative Chemoradiotherapy on the Number of Lymph Nodes Retrieved in Rectal Cancer

• DOI: 10.1097/sla.0b013e3181e61e33
• Publication Date: 2010-07-20T10:37:14Z
• Authors: Yun Hyung Ha; Seung-Yong Jeong; Seok-Byung Lim; Hyo Seong Choi; Yong Sang Hong; Hee Jin Chang; Dae Yong Kim; Kyung Hae Jung; Jae-Gahb Park
• Keywords: Adult; Aged, 80 and over; Male; Rectal Neoplasms; Radiotherapy Dosage; Middle Aged; Combined Modality Therapy; 3. Good health; 03 medical and health sciences; 0302 clinical medicine; Risk Factors; Lymphatic Metastasis; Antineoplastic Combined Chemotherapy Protocols; Humans; Lymph Node Excision; Regression Analysis; Female; Aged; Retrospective Studies

To evaluate the relation of preoperative chemoradiotherapy to the number of lymph nodes retrieved in curative intent surgery for rectal cancer.Current guidelines recommend evaluation of least 12 to 14 lymph nodes in rectal cancer. It is well known that lymph nodes retrieval is affected by many factors.This was a retrospective study of 615 patients who underwent curative intent surgery for primary rectal cancer. Preoperative chemoradiotherapy involving 50.4 Gy fractionated radiotherapy and concurrent chemotherapy was performed in patients with locally advanced rectal cancer (clinically T3 or T4). We explored associations between the number of lymph nodes retrieved in the pathologic specimen and patient demographics (age, gender, body mass index [BMI]), treatment (surgeon, sphincter-saving, preoperative chemoradiotherapy), and tumor-related variables (location, stage, histology). After adjustment for other factors, we compared the mean number of obtained lymph nodes between patients treated with preoperative chemoradiotherapy and those treated without preoperative chemoradiotherapy.Univariate analysis demonstrated that age, BMI, preoperative chemoradiotherapy, location, and stage significantly related the number of lymph nodes retrieved. Multivariate analysis revealed age, BMI, preoperative chemoradiotherapy, and stage as independent factors influencing the number of lymph nodes retrieved. The mean number of lymph nodes adjusted for age, BMI, and stage was significantly lower in patients treated with preoperative chemoradiotherapy than in those treated without preoperative chemoradiotherapy (14.5 vs. 21.5, P < 0.001). The reduction rate by preoperative chemoradiotherapy was 32.6% (7/21.5). In patients who underwent preoperative chemoradiotherapy, advanced age (P < 0.001) and high BMI (P = 0.037) were associated with decreased number of retrieved lymph nodes.Preoperative chemoradiotherapy significantly decreased the number of retrieved lymph nodes by approximately 33%. Therefore, the recommended number of retrieved lymph nodes should be adjusted when rectal cancer is treated with preoperative chemoradiotherapy.