Sex differences in the changing anatomic distribution of colorectal carcinoma

Abstract

The anatomic site distribution of large bowel cancer was studied in 2079 patients between 1967 and 1980. To measure the trend in the localization of the carcinomas, the slope of the regression line of the proportions at each site over the years was computed. The large bowel was divided into five segments: cecum, ascending colon and hepatic flexure, transverse and descending colon, sigmoid and rectosigmoid junction, and rectum. A significant decrease in the proportions of cancer in the sigmoid for both sexes (slope [b] = −0.89; P < 0.001) and an increase of cecal cancer (b = 0.54; P < 0.004) was observed. Sex‐specific results indicated the diminishing proportion of sigmoid cancer in men (b = −1.04; P < 0.004) with an increase in transverse and descending colon cancer proportions (b = 0.52; P = 0.012). In women, a negative slope of ‐‐0.74 was not significant for sigmoid cancer, but cancer of the cecum showed an increase in proportions (b = 0.80; P = 0.01). The age distribution indicated a significant decrease in proportion of men older than 80 years and of women in the age group of 40 to 49 years and an increase in women older than 80 years. However, age adjustment did not change any of the previous conclusions. The observed sex differences in the changing distribution within the large bowel over a 14‐year period cannot be explained by the improvement of diagnostic tools in the last years. In view of these findings, it is important to evaluate the possible sex‐related bias in the application of screening and preventive measures as well as the changes in the ecologic features of the large intestine.

Socioeconomic variation in colon cancer tumour factors associated with poorer prognosis

“…The findings, however, are more consistent with studies showing excess risk of rectal cancer in deprived patients (Ferraroni M et al, 1989;Kee et al, 1996), and with suggestions that colon subsites should ideally be treated differently in analytical epidemiological research. There was an excess likelihood of proximal colon subsite in women, as observed previously (Vobecky et al, 1984;Jass, 1991;Levi et al, 1991;Chen et al, 1997). The lower likelihood of proximal tumours in young age contrasts with previous research showing an inconsistent effect of age (Jass, 1991).…”

Anatomical Distribution of Colorectal Carcinoma in Iran: A Retrospective 15-yr Study to Evaluate Rightward Shift

“…Studies of Crerand et al (1991) evaluating the anatomical distribution of colorectal cancer in 1553 Irish patients over a 30 years period, Lanier et al (1973) over a 25 year period and Vobecky et al (1984) over 13 year period all showed a relatively stable rate of proximal lesions. Odigie et al (2009) studied the clinicopathologic characteristic of colorectal cancer in the Guinea Savannal region between 1981-2005, they found no shift in distribution subsite in (1981-1990) and (1991-2005).…”

“…Although left sided colon cancer are still more common, several studies were done about changes in anatomical distribution of this cancer in recent years. Proximal right ward shift was proven in some of these studies (Sariego et al, 1992;Cady et al, 1993;Nazarian et al, 1993;Cheng et al, 2001) and was not observed in others (Lanier et al, 1973;Vobecky et al, 1984;Crerand et al, 1991). Some believe that the rightward shift result from an absolute decrease in left sided cancer rather than true increase in incidence rate of right-sided colorectal cancer (Saltzstein et al, 1998;Cress et al, 2000;Rabeneck et al, 2003).…”

Colorectal cancer, one entity or three

“…Numerous reports revealed an increased incidence of colon cancer and a decreased incidence of rectal cancer; and a proximal shift in the incidence of CRCs was noticed. Despite the controversy (Crerand et al, 1991;Erkek et al, 2007;Ponz de Leon et al, 2004;Vobecky et al, 1984), the shift is evidenced by various population-based studies relating to both ethnicity (White (Troisi et al, 1999), African American (Nelson et al, 1997), and Asian (Ji et al, 1998)) and geography (Rochester (Beart et al, 1983), Canada (Obrand and Gordon, 1998), and New Zealand (Jass, 1991)). Association of the subsite distribution of colorectal cancer with race, gender, age, and other epidemiological factors has been detected through population-based data (Tables 2 and 3).…”