To provide the evidence of predicting and preventing the postoperative recurrence by investigating the relationship between the recurring types of colorectal carcinoma (CRC) after radical resection and clinicopathologic factors.
Data from 464 CRC patients in stage I–III, who were admitted to our hospital during a period from January 1998 to December 2002 and underwent radical surgery, were collected, and retrospective analysis of the clinicopathologic data from 90 out of the 464 CRC patients, who developed postoperative recurrence was conducted. The 90 patients were divided into 2 groups based on the recurrence time (RT). Those with a RT of ≤ 30 months were classified into the early recurrence (ER) group and those with RT of > 30 months were classified into late recurrence (LR) group. The χ2 test was used for univariate analysis, and binomial logistic regression analysis for multivariate analysis.
There were 78 patients (86%) in the ER group and 12 (14%) in the LR group. The median recurrence time (MRT) was 35.1 months, 13.6 months, and 12.9 months in CRC patients with stage-I, stage-II and stage-III, respectively. There were significant differences in RT among the groups (P = 0.001). In the 90 patients, the MRT was 17.4 months. The median time (MT) was 16.9 months in patients with regional recurrence, 13.3 months in patients with single recurrence, and 7.7 months in patients with multiple metastases. Univariate analysis indicated that the depth of tumor infiltration, the number of positive lymph nodes, and the macroscopic types of the primary tumor were the factors affecting the relapse of the tumor. The multivariate analysis revealed that the depth of tumor infiltration was the independent factor affecting the time of ER (P = 0.049).
Most of CRC patients receiving radical surgery for colorectal cancer occur recurrence within 30 months after the first operation, nevertheless, LR occurs in some CRC patients over 30 months after the surgery. The time interval varies in different types of recurrence. Distant metastasis is seen mainly in the cases with postoperative ER, and regional recurrence in the cases with LR. The depth of tumor infiltration is an independent predictor affecting the postoperative RT of CRC, and the tumor infiltration into, or beyond the seromembranous layer is considered as independent factor affecting the ER of CRC.