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 Table of Contents  
ORIGINAL ARTICLES
Year : 2021  |  Volume : 1  |  Issue : 1  |  Page : 19-25

Demographic profile and clinicopathological patterns of colorectal cancer in subhimalayan North India


1 Department of Radiation Oncology and Nuclear Medicine, Dr Rajendra Prasad Government Medical College, Kangra at Tanda, Himachal Pradesh, India
2 Department of Pathology, Dr Rajendra Prasad Government Medical College, Kangra at Tanda, Himachal Pradesh, India

Date of Submission30-Jun-2021
Date of Acceptance04-Dec-2021
Date of Web Publication06-Jan-2022

Correspondence Address:
Dr. Muninder Negi
Department of Radiation Oncology and Nuclear Medicine, Dr Rajendra Prasad Government Medical College, Ground Floor, Super Speciality Block, Kangra at Tanda 176001, Himachal Pradesh.
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/bjoc.bjoc_18_21

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  Abstract 

Background: Despite colorectal carcinoma being one of the common cancers with an increasing incidence over the past few decades, there are only a few studies that have assessed its demographic, clinical, and pathological profile in the north Indian population. Objective: To assess the demographic and clinicopathological patterns of colorectal cancer (CRC) among patients in the subhimalayan region of North IndiaMaterials and Methods: This retrospective cross-sectional study analyzed the data of 244 patients with CRC who were referred to a state-owned medical college in Himachal Pradesh, India, between January 2016 and April 2020. Demographic, clinical, and pathological information was extracted from patient record files. Results: The mean age of patients in the study was 51.2 years, with an age range from 19 to 81 years. Approximately 48% of the patients were aged between 40 and 60 years, 15% were younger than 40 years, 56% of the patients were male, and 44% of the patients were female. Rectal bleeding (~46%), change in bowel habits (~41%), and abdominal pain (39%) were the common clinical symptoms. Overall, 73% of the patients were diagnosed at a mean duration of five months after the onset of their symptoms, and approximately 36% of the patients were in stage II and 48% were in stage III at the time of diagnosis. Colon carcinoma accounted for 76% of the patients, 17% had rectal carcinoma, 5% had carcinoma of recto-sigmoid, and 2% of the patients were diagnosed with ano-rectal carcinoma. Histopathologically ~ 81% patients had adenocarinoma, 14% had mucous carcinoma, 3% had signet ring carcinoma, and 2% had NET. Conclusions: In the subhimalayan region in North India, CRC has a higher male gender predominance, with a substantial number of patients younger than 40 years. Most of the cases are diagnosed after a mean duration of five months of the symptoms. Colon carcinomas are more common than rectal carcinomas, with left-sided colon carcinomas being more common than right-sided colon carcinomas. The majority of tumors are adenocarcinomas, whereas mucinous carcinomas are less common and signet ring carcinomas are rare. A greater number of patients with right-sided colon carcinomas have a higher stage and a more aggressive tumor grade at the time of diagnosis. The study also shows that there is a need to be more vigilant for colorectal carcinoma in patients with lower GIT symptoms and it lays emphasis on a colorectal screening program in such patients, to enable early detection of this tumor.

Keywords: Clinicopathological, colorectal cancer, demographic, subhimalayan North India


How to cite this article:
Gupta N, Verma S, Negi M, Devi S. Demographic profile and clinicopathological patterns of colorectal cancer in subhimalayan North India. Bengal J Cancer 2021;1:19-25

How to cite this URL:
Gupta N, Verma S, Negi M, Devi S. Demographic profile and clinicopathological patterns of colorectal cancer in subhimalayan North India. Bengal J Cancer [serial online] 2021 [cited 2022 May 21];1:19-25. Available from: http://www.bengaljcancer.org/text.asp?2021/1/1/19/335057




  Introduction Top


CRC is the third most commonly diagnosed cancer worldwide, with 1.8 million cases diagnosed every year. It is the second most leading cause of cancer-related mortality, causing 862,000 deaths. The estimated number of cases diagnosed worldwide in the year 2018 were 10.2% of all new cancer cases.[1]

In India, colorectal carcinoma is one of the top five frequent cancers and it contributed to 6.5% and 3.4% of all new carcinoma cases among male and female patients, respectively, in the year 2018.[2] CRC is generally considered as a cancer of old age, with peak incidence in the fifth decade.[3] However, the incidence of CRC has been increasing in the younger population, especially in developing countries, including the Asian continent, which is attributable to a change in lifestyle and dietary habits.[4],[5],[6],[7] Population-based time trend studies show a rising trend in the incidence of CRC in India.[8] Limited data from rural population-based registries indicate that the incidence rate of rectal cancer is disproportionately higher in rural India.[9],[10],[11] The five-year survival of CRC in India is lowest in the world, approaching to less than 40%. In fact, the CONCORDE-2 study reveals that the five-year survival of rectal cancer in India is actually declining in some registries.[12]

The CRC originates from epithelial tissue of the colon, and it may be found on either the right or the left side of the colon. Depending on location, CRCs differ in terms of disease progression, treatment response, and overall survival. The difference between these tumors can be attributed to different anatomical and developmental origin, differential molecular expression, various other carcinogenic factors (such as difference in bacterial population on the two sides of the colon, or exposure to distinct nutrients and bile acids), or a combination of all that has been just cited.[13]

There are a few published studies from India on patients with CRC, but studies on the demography and clinical presentation of patients with CRC in north India are lacking. Therefore, the profile of patients with CRC in this region is largely unknown. Hence, we have conducted a baseline study to assess the demographic and clinical profile of patients with CRC, which may help for planning strategies to tackle this disease.


  Materials and Methods Top


Study design and setting

To assess the demographic and clinicopathological pattern of CRC in a subhimalayan region in North India. We have conducted this retrospective, cross-sectional, hospital-based study and analyzed the data of 244 patients with CRC.

Study population and data collection

The study included the data of all patients with lower GIT symptoms who presented to the institute and were diagnosed with CRC, between January 2016 and April 2020. The demographic data of all patients (i.e., age, gender) as well as the specific location of lesions within colorectal loops, histopathological type, and grades were obtained. This study was approved by the research committee of the institute.

Statistical analysis

Data were analyzed by using SPSS version 20 (IBM, Armonk, NY,USA). All data are represented as simple frequencies and percentages.


  Results Top


A total of 278 patients presented with lower GIT symptoms between January 2016 and April 2020. All the patients had undergone CECT of the abdomen and pelvis along with colonoscopic examinations and were subsequently confirmed histopathologically as having colorectal carcinoma. Of these, 34 patients were excluded from the study due to insufficient data/missing records; therefore, a final analysis was done on 244 patients.

There were 136 (~56%) male and 108 (~44%) female patients. The mean age was 51.2 years, with an age range from 19 to 83 years. The demographic profile of patients included in the study is shown in [Table 1].
Table 1: Demographic profile of the study population

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Out of 244 patients, 178 (~73%) were diagnosed with CRC after four to six months of the onset of their symptoms, 39 (~16%) were diagnosed later than six months, and 27 (~11%) were diagnosed within one to two months of the disease onset. In terms of chief complaints, bleeding per rectum (~ 46%), altered bowel habits (~ 41%), and pain in the abdomen (~ 39%) were the common symptoms at the time of presentation.

CRC was the initial provisional diagnosis in 63 (~26%) patients referred to the institute whereas fissures, hemorrhoids, IBD, or intestinal tuberculosis accounted for the majority (74%) of the initial provisional diagnosis. Positive family history of a GIT tumor/malignancy was documented in six (~2%) patients, whereas 83 (~ 34%) patients had no family history of malignancy. However, in a large number of patients (156, ~64%), the documentation of family history of a GIT disease was missing.

On radiological imaging and colonoscopy, 146 (~60%) patients had a lesion on the left-sided colonic loops (left colorectal carcinoma [LCRC]) whereas 98 (~40%) patients had right-sided colonic lesions (right colon carcinoma [RCRC]). The pattern of colorectal carcinoma in the study population with respect to the side of involvement, subsite wise and histopathological specific distribution of lesions in percentage terms is shown in [Figure 1].
Figure 1: Percentage of left- vs. right-sided CRC, subsite and histopathological type specific distribution of lesions in the study population

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In terms of the genderwise distribution of lesions, among males, the ascending colon (~31%) followed by the sigmoid (~15%) were more commonly involved at primary sites; however, in female patients, the rectum and the anorectum (~30%), followed by the sigmoid colon (~19%) were the common primary sites involved [Figure 2].
Figure 2: Distribution of CRC subsites among male and female patients

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With respect to TNM staging, overall, eight (~3%) patients were in stage I, 89 (~ 36%) in stage II, 115 (~48%) in stage III, and 32 (~13%) in stage IV disease at the time of presentation. The stagewise distribution of patients with RCRC and LCRC is shown in [Figure 3].
Figure 3: Number of patients in different TNM stages among right vs. left CRC patients

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Histopathologically, 198 (~ 81%) patients were diagnosed with adenocarcinomas, 34 (~14%) with mucinous carcinoma, eight (~3%) with signet ring histology, and four (~2%) with NET of the rectum. The histopathological subtype and differentiation grades of the lesions are shown in [Table 2].
Table 2: Histopathological types and differentiation of CRC lesions in the study

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  Discussion Top


CRC is a common cancer worldwide that can affect any age group and affect both genders.[14] It is one of the five common cancers in India.[2] However, the studies pertaining to demographic, clinical, and pathological patterns of CRC in the north Indian population are scarce. Moreover, to the best of our knowledge, no such study has been carried out in the rural region of north India in the past.

In our study, a higher number of patients with CRC were male (56%), with a male-to-female ratio of 1.26:1. These findings are similar to the findings in a few other studies on the Indian population, such as those by Patil et al.[15] and Suryadevara,[16] which had a similar male-to-female distribution pattern of CRC. Also, in the global scenario, CRC has been documented to be more common among men in most of the regions.[17]

The mean age of patients in our study was 51.4 years. Forty-eight percent of patients were in the age group of 40–60 years, 15% of patients were younger than 40 years, and 37% were older than 60 years. Overall, 64% of the patients were younger than 60 years of age. The findings are somewhat similar to those in a study by Patil et al.,[15] where mean age was found to be 47.2 years, and 35% of the patients were younger than 40 years of age, whereas 80% were younger than 60 years. In another study in eastern India,[18] the mean age at presentation was reported to be 47.01 years, whereas it was found to be 58.4 years in a retrospective descriptive analysis[19] of 220 cases with CRC diagnosed at colonoscopy over a five-year period. Some other studies from different parts of India have raised the concern of the onset of CRC in a younger age group in India.[19],[20] Furthermore, in most developing countries, diagnosis occurs at a relatively younger age than in developed countries.[16],[21],[22]

The patients commonly presented with clinical symptoms of bleeding per rectum (~46%), altered bowel habits (41%), and pain in the abdomen (~ 39%). This is similar to the symptoms of colorectal carcinoma reported in some of the other studies.[16],[23],[24]

A large number of patients in the study presented relatively late, after a mean duration of five months of their symptoms. This pattern was similar to findings in some other studies on patients with CRC in India, such as those by Patil et al.[15] and Suryadevara et al.,[16] which reported the mean duration of symptoms to be four and six months, respectively. The reason for such late presentation could be attributed to illiteracy and low educational levels, resulting in low health awareness and knowledge among the patients, which leads them to either initially ignore their symptoms or at the most seek local indigenous treatments resulting in a delayed diagnosis. Further, in the subhimlayam region, being a hilly terrain, patients have to travel long distances, often from remote areas, to access adequate health-care facilities, resulting in a delayed diagnosis. Most of the patients with a delayed diagnosis were initially misdiagnosed for hemorrhoids, fissures, inflammatory bowel disease, or intestinal tuberculosis whereas CRC was considered as an initial diagnosis in only 63 (~26%) of the referred patients. These findings highlight a need among health professionals to be more vigilant for colorectal carcinoma in patients with lower GIT symptoms. Also, there is a need for a colorectal screening program such as occult fecal blood testing or colonoscopy in patients with lower GIT symptoms, which would enable an early diagnosis and treatment of CRC.

The available literature reports 5% to 10% of cases with CRC as being hereditary in origin. In our study, positive family history of a colonic tumor was found in six (~2%) patients, whereas a substantial number of patient records lacked this information. This is possibly attributable to the reason that initial OPD assessment of patients visiting the referral institute was carried out by resident doctors in different years of their training and hence the documentation of family history was missed out in many patients. This stresses the need for educating the clinicians about the need for taking detailed family history in all cases of CRC.

CRC has been classified into RCRC and LCRC. RCRCs are located within the colon, which includes the proximal two-thirds of the transverse colon, ascending colon, and cecum. LCRCs occur within the colon, which includes the distal third of the transverse colon, splenic flexure, descending colon, sigmoid colon, and rectum.[25],[26] Besides the difference in their origin, these tumors exhibit a different histology. Right-sided tumors show sessile serrated adenomas or mucinous adenocarcinomas, whereas left-sided tumors show tubular, villous, and typical adenocarcinomas.[27] Because of their polypoid morphology, LCRC are easier to detect with colonoscopy in the early stages of carcinogenesis. The RCRC lesions have a flat morphology that is difficult to detect. Further, patients with RCRC tend to have advanced and bigger tumors, which are often poorly differentiated.[28],[29]

Metastatic pattern also varies depending on the primary location of the CRC. RCRCs more often metastasize to the peritoneum, whereas a greater proportion of LCRC metastasizes to the liver and the lung.[9] The differences in molecular characteristics such as the expression of EGFR and EGFR ligands and KRAS mutations result in differences in treatment response, clinical outcome, and prognosis in patients with CRC, with RCRC displaying a markedly worse prognosis.[30],[31],[32] Several studies have also reported differences in treatment outcomes with EGFR and VEGF inhibitors in patients with CRC, with anti-EGFR such as cetuximab providing a clinical benefit to patients with LCRC who have the RAS WT mutation; however, this benefit is not relevant for patients with RCRC.[33] Similar results were obtained with CRYSTAL and FIRE trials as well.[34]

In our study, 60% of the patients had LCRC, whereas 40% of the patients had RCRC. Colonic carcinoma was found in 76% of the patients, whereas rectal carcinoma was found in only ~17%, anorectal in ~2%, and recto-sigmoid carcinoma in ~ 5% of the patients. These findings are different from those reported by Patil et al.,[15] where though the left colon was also the more commonly involved site, yet the most common primary site was the rectum (41%) followed by the recto-sigmoid (21%), anorectum (13%), and colon (25%) with only 18% patients having a primary tumor in the right colon. Also, in a few other Indian studies such as those by Suryadevara et al.[16] and Sudarshan et al.,[20] the rectum was reported to be the most common site (~ 80% of patients) whereas colon cancer was found in ~20% patients only. This difference in the findings of our study with a higher prevalence of colonic carcinoma as compared with rectal carcinoma in other studies, along with a relatively higher percentage of right colon involvement, could be because of dietary or genetic factors in the study population but it needs further studies to determine the exact etiopathological factors involved.

A majority of patients with CRC were diagnosed in stage II (89 patients ~36%) or III (115 patients ~ 48%) of the disease, whereas diagnosis at an early stage (stage I) was much less (~3.2%). The findings are similar to those of a study by Patil et al.[15] and show that a vast majority of the patients had a relatively advanced stage of the disease at the time of presentation. This could be attributed to the lack of population-based screening and also socioeconomic factors as previously discussed, which lead to a delayed access to health care. Further, it was seen that a greater percentage of patients with RCRC had a higher stage of disease at the time of diagnosis. The findings of the present study are similar to some of the other studies[35],[36],[37] that report more advanced stages in patients with RCRC, in contrast to LCRC.

The most common histopathological type of the tumors in this study was adenocarcinoma (~81%) followed by mucinous carcinoma (~14%), whereas signet ring carcinoma and NET were much less common. This is in agreement with the results of other studies,[17],[18],[21],[22] where adenocarcinoma was the most common histopathological type, followed by mucinous carcinomas whereas signet ring carcinomas, lymphomas, and NET were much less common. Similarly, other studies have shown that the signet ring type comprises only about 1% of all colorectal carcinomas.[38],[39],[40]

With respect to tumor differentiation, a greater number of patients with RCRC had a higher grade of carcinoma compared with the patients with LCRC. Again, the results of our study are consistent with some of the other studies in the literature reporting a comparatively higher grade of tumor in patients with RCRC compared with patients with LCRC.[35],[36],[37] It is well known that low-grade carcinomas are associated with better treatment outcomes and higher quality of life compared with higher grade carcinomas.


  Conclusions Top


CRC is a common cancer with a rapidly increasing incidence worldwide, including India. Though CRC is often considered a tumor of the elderly population, the disease has been affecting the younger population as well. The current study found that CRC is the most common in those aged between 40 and 60 years but is not uncommon in patients younger than 40 years of age and can occur in virtually any age group. Patients with CRC are diagnosed relatively late after the onset of their symptoms, often at an advanced stage (mostly in stage II or III). Since 5% to 10% of the CRCs are hereditary, a proper evaluation of family history is important in these patients. Unfortunately, even in tertiary centers such as ours, documentation of this aspect of CRC was inadequate.

Therefore, keeping in view the findings of our study, trainees and physicians working at various health institutions need to be more vigilant for CRC, especially in patients with suspicious lower GIT symptoms. Also, the assessment and documentation of family history needs to be improved, once a diagnosis of CRC is settled. Further, there is a need to initiate CRC screening program in the region, so as to enable early detection of the disease, which would result in a more favorable treatment outcome in these patients.

Limitations of the study

Our study was retrospective in nature and limited to a single institute with a moderate sample size. To further analyze the data on CRC among patients in the region, a larger sample size with a wider area coverage would be needed. Therefore, in future, further studies, including multicenter studies, should be conducted in order to study the demographics and clinicopathological patterns of CRC in the rural regions of north India.

Ethical considerations

Ethical approval for this study was obtained from the research committee of the institute. The patient data have been kept completely anonymous, for ethical reasons. No patient consent was required, as this was a retrospective study.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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