Histomorphological Study of Lower Gastrointestinal Tract Lesions in Per Rectal Bleeding Cases

The present study on the histomorphology of lower gastrointestinal tract lesions in patients presenting with per rectal bleeding was two years (June 2015 to May 2017) cross-sectional study carried out in the department of pathology of a tertiary care hospital and included 40 cases. Constipation was the most typical associated symptom along with per rectal bleeding. Clinical details and radiological investigations helped in making the diagnosis of all lesions of the lower gastrointestinal tract causing per rectal bleeding. The mean age at presentation in benign lesions was 33 years, while the mean age at presentation in malignant lesions was 61 years. The mean age at presentation of adenocarcinoma was 62 years. Majority of cases of adenocarcinoma presented with Astler-Coller stage C1. The other malignancies of the lower gastrointestinal tract causing per rectal bleeding were clonogenic carcinoma, neuroendocrine carcinoma and moderately differentiated squamous cell carcinoma. The most common cause of per rectal bleeding amongst the lower gastrointestinal tract is a neoplastic lesion. The lesions of the lower gastrointestinal tract causing per rectal bleeding are seen more commonly in male patients with a predominant age group of above 40 years, and constipation is the most typical associated symptom in these cases. The most common cause of per rectal bleeding amongst the lower gastrointestinal tract is a neoplastic lesion.


INTRODUCTION
Rectal bleeding occurs in 20% of the population annually in India. As is believed to be a common symptom in the general population, it is still unclear which patients require investigations to exclude severe underlying pathology. (Lewis et al., 2002) Mortality for lower gastrointestinal bleeding is around 11% and reaches to 21% for the acute massive category. Khandelwal (2003) It is considered to be an important sign of colonic diseases, in particular of colorectal cancer. Histopathological study plays an important role in the proper management of cases of lower gastrointestinal tract lesions.
The present study includes the diagnosis of lower gastrointestinal tract lesions in cases of per rectal bleeding. Different types of equipment like rigid proctosigmoidoscopy, lexible sigmoidoscopy, colonoscopy and anoscopy are designed to examine the lesions of the large intestine.

Aim
To study the histopathology of various lower gastrointestinal tract lesions in patients presenting with per rectal bleeding.

Objectives
To categorize different lower gastrointestinal tract lesions leading to per rectal bleeding and assess their proportions into Nonneoplastic (that is infectious, in lammatory, idiopathic) and Neoplastic (that is benign & malignant). To correlate the histopathological indings with age, sex, site of the lesion, radiological & endoscopic indings (Wherever possible).

REVIEW OF LITERATURE
Rectal bleeding is a common symptom, but a small number of patients consult their doctors. Patients investigated in hospital represent the 'tip of the iceberg' of all people with this symptom. Although few population-based studies have investigated this issue and very little data is available (Ellis and Thompson, 2005).
A range of colonic diseases (both benign and malignant conditions) present as per rectal bleeding. Dysplasia was irst postulated to be a precursor of carcinoma in ulcerative colitis by Warren and Sommers in 1949 (Riddell et al., 1983). The most detailed account of the pathology of intestinal tuberculosis was given by Hoon et al. in 1950. (Tandon andPrakash, 1972) It was in 1925 that Crohn B.B et al. irst reported carcinoma of the large bowel in a patient with a history of ulcerative colitis. Obernderfer irst diagnosed carcinoid tumour as a speci ic entity in 1907 (Hinojosa et al., 2019). In 1932 at St. Mark's hospital in London Dr Cuthbert Dukes, pathologist, irst devised Dukes staging classi ication for colorectal carcinomas and later Gabriel, Duke, Bussey redeined the classi ication of Dukes in 1935.
Lower gastrointestinal tract extends from ligament of treitz to the anus, which includes part of the small intestine (jejunum and ileum), large intestine and anal canal (Standring et al., 2005), of blood in the veins of the hemorrhoidal plexus is usually caused by dependency. Haemorrhoids can be presented within or outside the anus. Microscopically dilated thick-walled submucosal vessels and sinusoidal spaces, often with thrombi and adjacent haemorrhage are seen. The surface epithelium may be colorectal, anorectal transitional zone-type, squamous.
Local complications of ulcerative colitis are perforation with peritonitis and abscess, toxic megacolon, venous thrombosis and carcinoma. The current risk of neoplastic change is 2%. The risk of carcinoma is higher where the entire colon is involved; when the disease is continuous, ongoing, long-standing and when the disease begins in childhood. (Morson, 1985) Diverticular disease describes the condition of having diverticula, usually asymptomatic, while diverticulitis refers to in lammation of the outpouchings (Goldstein and Ahmad, 1997). The disease occurs over the age of forty years. Naturally, the incidence of diverticulosis at autopsy is higher. The disease is characteristically multiple and involves the left side of the colon. The sigmoid colon is most commonly affected (Hughes, 1969). The complications of Meckel's diverticulum include perforation, vesico diverticular istula, ulceration, haemorrhage, intussusception, intestinal obstruction from attached bands and tumours. The ulceration is of peptic type, caused by acid secretion from the ectopic gastric mucosa and is usually in the adjacent ileum rather than in the Meckel's diverticulum itself. It may result in massive haemorrhage, particularly in children. Helicobacter pylori do not seem to be involved in the pathogenesis.
Most cases of intussusception are seen during the irst ive years of life, with over one-half occurring during the irst year. This is probably related to the fact that the amount of lymphoid tissue in the ileocecal region and the degree of projection of the valve into the cecum are at their maximum during this period and that both decrease substantially after the second year. There is now general agreement that the lymphoid hyperplasia precedes and is often the cause of the intussusception rather than the result, although secondary in lammatory changes certainly occur. This lymphoid hyperplasia, which is limited to the mucosa and submucosa, is probably of viral aetiology in many instances, as indicated by the inding of intranuclear inclusion bodies in one-third of the cases and the fact that viruses (particularly adenoviruses) have often been isolated from these children. Several cases of intussusception caused by lymphoid hyperplasia in AIDS patients have been reported. (Rosai, 2011) According to Dailey and Garret (1971), sex and age distribution of this tumour parallels that of ordinary adenocarcinoma of the rectum (Dailey and Garret, 1971). Giacchero et al. (1985) reported the maximum incidence in the age group of 41-50 years with male preponderance. According to them, the most common site for signet ring cell carcinoma is the rectum (55-56%). (Giacchero et al., 1985) Chowdhury et al. (1975) reported 15 cases of primary linitis plastica of the colon with 12 patients showing lymph node involvement and 6 with the involvement of ovaries. Hepatic metastasis which is common in usual forms of colonic carcinoma is rare in primary linitis plastica type of carcinoma. According to them, the prognosis of these patients has been low, with a survival rate between 2 weeks to 27 months. Chowdhury et al. (1975); Balthazar et al. (1979) have shown that prognosis has been poor with a mean survival of only four months after the diagnosis has been established. (Balthazar et al., 1979) According to Giacchero et al., signet ring carcinoma has high local invasiveness. (Giacchero et al., 1985)

MATERIALS AND METHODS
The present study on the histomorphology of lower gastrointestinal tract lesions in patients presenting with per rectal bleeding was a coming two years (June 2015 to May 2017) cross-sectional study carried out in the department of pathology of a tertiary care hospital. The present study included a total of 40 cases of lower gastrointestinal tract lesions causing per rectal bleeding.
Surgical specimens of all lesions from the lower gastrointestinal tract in the form of excision or resection from patients of all age groups and both sex presenting with per rectal bleeding. Clinical data of the patients in the form of their age, sex, associated complaints with a primary complaint of per rectal bleeding, complete blood count, endoscopic indings and radiologic impressions if any were obtained from the patient hospital case sheets available directly from the wards or were obtained from the medical record section.

OBSERVATION AND RESULTS
The present study on the histomorphological features of lower gastrointestinal tract lesions in patients presenting with per rectal bleeding was a prospective two years (June 2015 to May 2017) cross-sectional study carried out in the department of pathology of a tertiary care hospital and recorded total 40 cases. The present study included surgical specimens of all the lesions from the lower gastrointestinal tract in the form of excision or resection from patients of all age groups and both sex presenting with per rectal bleeding. In contrast, patients with all kind of bleeding disorders were excluded from the study.
In the present study, the histomorphological features of lower gastrointestinal tract lesions according to age and sex of the patient were analyzed. Of the total 40 cases, most of the lesions that are 15 cases (37.5%) of the lower gastrointestinal tract were observed in the age group 41 to 60 years followed by 14 cases (35%) in the age group more than 60 years. Youngest patient's age was six years while the oldest patient was of 82 years old. Mean age at presentation was 56.37 years. (Table 1) Investigations in the form of radiological imaging and endoscopic indings were available in 36 cases out of 40 (90%). In the remaining 4 cases, diagnosis of haemorrhoid was given clinically, which were then excised and sent for histopathological examination for con irmation. A radiological investigation done was in the form of mainly sigmoidoscopy in 20 cases that is (55.5%) followed by computed tomography scan (CT) in 10 cases (27.7%), magnetic resonance imaging (MRI) in 3 cases (8.3%), ultrasonography (USG) in 2 cases (5.5%) and barium enema in 1 case that is (2.7%). In all 31 malignant lesions that are in 86.11% of the lower gastrointestinal tract causing per rectal bleeding, histomorphological indings were matching with radiological imaging indings. While in remaining that is in 5 cases (2 nonneoplastic each of tuberculosis and Meckel's diverticulum, three benign that is two adenomas and one juvenile polyp) radiological indings helped to arrive at a de initive diagnosis. Histological indings were correlated with radiological indings, and the de initive diagnosis was given. (Table 2) In the present study, the distribution of growth patterns of 31 malignant lower gastrointestinal tract lesions causing per rectal bleeding were analyzed. An ulcero proliferative pattern of growth was found in the majority that is 15 cases (48%) followed by ulcero in iltrative growth pattern in 9 cases (29%). (Table 3) In the present study, out of a total of 40 cases of lower gastrointestinal tract lesions from patients with per rectal bleeding, 6 cases (15%) were nonneoplastic. Haemorrhoids were found to be the most common nonneoplastic lesions with 4 cases (66%) followed by 1 case (17%) each of tuberculosis and Meckel's diverticulum. (Table 4)

DISCUSSION
The present study on histomorphology of lower gastrointestinal tract lesions in patients presenting with per rectal bleeding was a prospective two years (June 2015 to May 2017) cross-sectional study carried out in the department of pathology of a tertiary care hospital and included total 40 cases.
In the present study, histomorphological features of lower gastrointestinal tract lesions in patients presenting with per rectal bleeding were analyzed according to the age and sex of patients. Majority of cases were from the age group of 41 to 60 years

CONCLUSION
The lesions of the lower gastrointestinal tract causing per rectal bleeding are seen more commonly in male patients with a predominant age group of above 40 years, and constipation is the most typical associated symptom in these cases. The most common cause of per rectal bleeding amongst the lower gastrointestinal tract is a neoplastic lesion. The primary cause of per rectal bleeding amongst nonneoplastic lesions of the lower gastrointestinal tract is a haemorrhoid, and male patients are commonly affected. Haemorrhoid is the commonest cause of anaemia amongst nonneoplastic lesions of the lower gastrointestinal tract causing per rectal bleeding.
Adenoma and juvenile polyp form the majority of benign lesions of the lower gastrointestinal tract causing per rectal bleeding. Malignant lesions are predominant of all neoplastic lesions of the lower gastrointestinal tract causing per rectal bleeding. Most of these are adenocarcinomas involving the rectum and sigmoid colon. Overall male preponderance is observed in these cases. Adenocarcinoma of the rectum and sigmoid colon is the commonest cause of anaemia in cases of lower gastrointestinal tract lesions presenting with per rectal bleeding.

Funding Support
The authors declare that they have no funding support for this study.