Study of Clinicopathological Profile of Sporadic Cases of Colorectal Cancer

ABSTRACT Objectives Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the world. This study was carried out to see the epidemiological and clinicopathological profile of sporadic cases of CRC in Bangladesh. Materials and methods The patients diagnosed to have colorectal carcinoma in two private medical centers of Bangladesh from January 2012 to December 2014 were enrolled in this study. Demographic data, clinical presentations, site of lesions, and histological types were analyzed. Results Total 158 patients were included in this study. The mean age was 50.77 years and male to female ratio was 1.55:1. Rectal bleeding was the commonest symptom irrespective of age and sex followed by abdominal pain (33, 20.9%), weight loss (29, 18.3%), abdominal mass (26, 16.4%), and altered bowel habit (22, 13.9%). Common histological type was adenocarcinoma (156, 98.7%). Conclusion Colorectal cancer commonly affects males >40 years of age. Most common site of involvement is rectum, which is followed by left colon. How to cite this article Saha M, Shil BC, Saha SK, Banik RK, Perveen I, Chowdhury MKS, Nazmul Islam ASM, Saifullah ANM. Study of Clinicopathological Profile of Sporadic Cases of Colorectal Cancer. Euroasian J Hepato-Gastroenterol 2016;6(2):134-136.


INTRODUCTION
Worldwide, colorectal cancer (CRC) is the third most common cancer and the third leading cause of cancerrelated death in both males and females. 1,2 Globally, the highest incidence of CRC rates are in North America, Australia, and Europe, and the lowest rates in Africa and Asia. 3,4 Incidence of CRC worldwide is 6.5 and 7.7/100,000 females and males respectively. In developed countries, incidence varies from 50 to 60/100,000 population. 3 It is a rare diagnosis before the age of 40 years, with the incidence beginning to increase significantly between the age of 40 and 50 years and age-specific incidence rates increasing in succeeding decades thereafter. 5 It has been seen that 90% of new cases are diagnosed in patients over 50 years of age, 6 but now incidence in younger population interviewed, and demographic data, clinical and pathological reports were recorded in preformed questionnaire. Age, sex, occupation, family history of cancer (CRC and others), site of lesion, and histopathological types were recorded. Splenic flexure was taken as demarcating point of proximal and distal lesions.
Data were analyzed using Statistical Package for the Social Sciences 16 version. Chi-square test was performed to see significance, and p-value <0.05 was taken as significant.

RESULTS
A total of 158 patients with CRC were enrolled in this study. Age of the patients varied from 17 to 90 years, with mean 50.77 years. Ninety-six (60.75%) patients were male and 62 (29.25%) were female (Table 1).
Rectal carcinoma was found in 97 patients, with age varying from 17 to 90 years (mean 48.422 and standard deviation 18.42). Among them, 68 were smokers (p = 0.000) and 82 were betel nut chewers (p = 0.006). Only two patients were alcoholic. Three patients had family history of CRC. Of them, 118 were from rural areas, while rest were from urban areas (p = 0.353) ( Table 1).
In this series, 105 patients were in above 40 years age group, while remaining 53 were up to 40 years of age. Proximal colon was affected in 44 patients, while distal colon lesion involvement was in 114 patients. Among them, rectum was affected mostly (97 cases), where the difference was statistically significant (p = 0.00) ( Table 3). Overall, rectum was the most common site of lesion.
All but two were adenocarcinoma histopathologically and remaining two involving anal canal were squamous cell carcinoma.

DISCUSSION
Colorectal cancer is a major cause of morbidity and mortality throughout the world with large geographical variation. 10 Though CRC is a disease of old age, nowadays, more younger patients are affected. 11 In this study, 53 (33.6%) were within 40 years age group, which is higher than that reported from the Western world. This can be explained due to differences in population structures and in life expectancies. Mean age of CRC in our series is 50.77 years, which is earlier in comparison to non-African-Americans in the United States (70.5 years). 12 Reports from Japan and Korea 13,14 suggest that incidence of CRC is increasing in Asia. It may be due to change in food habits and lifestyle.
The most common location of CRC in this series is distal to splenic flexure. It is consistent with reports from Malaysia, Islamic Republic of Iran, Japan, Africa, India, and Egypt. [15][16][17][18][19][20] However, Western reports 21 and few reports from Korea 22 and Japan 17 show that there is a shift of tumor location to proximal part of colon. In our study, sparing rectal carcinoma, colon carcinoma was more on proximal colon (44 vs 34).
Male and female ratio was found to be 1.7:1 in our series (older group 1.62:1, younger group 1.4:1). Overall,  CRC incidence and mortality rates are about 35 to 40% higher in men than in women. The reason for this is not completely understood, but likely reflex complex interactions between gender-related differences, exposure to hormones, and risk factors 23 may be involved. Symptoms and signs at presentation are different for proximal and distal CRC. Bleeding per rectum and features of obstruction are highly suggestive of distal CRC, while abdominal pain and obstruction, anorexia, anemia, and mass are suggestive of proximal CRC. These are consistent with our series. 24 In our series, smoking and tobacco use has been found to be a statistically significant associated factor for CRC.