A Clinical Analysis of 475 Cases of Colorectal Cancer

ABSTRACT

Colorectal cancer is the third most common malignant neoplasm worldwide and the fourth most common cancer in Korea. Recently, incidence of colorectal cancer is increasing steadily. Because of advances in diagnostic tools, such as colonofiberoscopy, early detection of colorectal cancers is available. The survival rates of colorectal cancer is increasing due to early detection and advances in adjuvant therapy, such as chemotherapy and radiotherapy. The clinical analysis was made on 475 patients with colorectal cancer who have been admitted and operated at the Department of Surgery, Chonnam University Hospital, from January, 1987 to December, 1996. The results were as follows: 1) The peak age group was in the sixth(29.7%) and seventh decade(29.7%) followed by the fifth decade(17.3%) of life. The male: female ratio was 1.1:1. 2) The annual incidence was increased steadily, but since 1994, plateau in incidence has occurred. 3) The most common site was the rectum(62.7%). 4) Common symptoms and signs were anal bleeding(40.1%) and abdominal pain (28.1%). According to site, anal bleeding was the most common complaint in the rectum and left sided colon and abdominal pain was in other colons and cecum. 5) The most common stage by TNM staging system was stage II (38.7%). 6) Most cases of colorectal cancer were adenocarcinoma(97.7%), well differentiated lobular adenocarcinoma(55.6%) in which was the most common histopathologic type. 7) Preoperative circulating CEA(carcinoembryonic antigen) level was checked in 396 patients(83.4%). CEA was less than 10.0 ng/ml in 295 cases(74.5%) and more than 10.0 ng/ml in 101 cases(25.6%). 8) DNA ploidy was checked in 197 cases(41.5%). There ware aneuploid in 102 cases, diploid in 95 cases. 9) Curative surgery were performed in most cases. The most common surgical procedure was low anterior resection(35.4%). 10) Postoperative complications were developed in 63 patients(13.3%). The most common complication was wound infection in 12 cases(19.0%). 11) The overall 5-year survival rate for patients with colorectal cancer was 55.9%. The difference of 5-year survival rate between diploidy and aneuploidy of DNA content was not significant statically(p=0.97). But, patients of preoperative serum CEA level over 10 ng/ml had a low survival rate compared with those under 10 ng/ml(p=0.0002). And also those of tumor size over 3 cm had a low survival rate compared with those under 3 cm(p=0.002).