Abstract
BACKGROUND: The free margin of distal resection is an attempt to prevent local recurrence of the tumor and prolong survival. The recommended length of distal resection margin are varied among the researchers. This study was done to know the correlation between extents of distal intramural spread (DIS) and histology grading, stage and CEA levels of colorectal cancer. METHODS: The design of the study was a cross sectional. Sample was patients diagnosed with colon or rectal adenocarcinoma in the period of September 2017-March 2018 and underwent resection at Dr.Kariadi Hospital. Resected fresh tissue tumors were directly measured for the distal resection margin and histopathologic examination done by anatomical pathologists. This study has been approved by the ethics committee of Dr.Kariadi Hospital/Faculty of Medicine Diponegoro University. The relationship between DIS length to histology grading, tumor stage and CEA level were analyzed using Spearman's correlation test. RESULTS: The subjects of this study were 26 patients with colorectal cancer consisted of 15 men and 11 women. The average age of the patients was 53,04 years. The locations of the tumor were 17 in the rectum and 9 in the colon. The length DIS were between 1,07 and 11,49 mm. The longer DIS were occurred when the grading histology worsens, the tumor stage increases and the higher CEA levels with correlation coefficient were r = 0,77 (p < 0,001); r = 0,66 (p < 0,001) and r = 0,44 (p = 0,024) respectively. For the rectal location, the DIS length range were 0,28-10,36 mm. The longer DIS when grading histology worsens r = 0,59 (p = 0,012) and an increased tumor stage r = 0,73 (p = 0,001). The DIS length of the rectum was not proven to correlate with elevated CEA levels r = 0,14 (p = 0,588). CONCLUSION: Histological grading, tumor stage and CEA levels can be predictors of distal intramural spread (DIS) colorectal cancer. The strongest correlation were between DIS and histologic grading. Thus, in mid and lower third of the rectal cancer, the histologic grade examination is strongly recommended. Based on this study, it is recommended that in rectal cancer undergoing sphincter preserving surgery distal resection sould be more than 2 cm from the tumor margin.