Colorectal carcinoma in Lagos and Sagamu, Southwest Nigeria: A histopathological review

The African Research Group for Oncology: A decade fostering colorectal cancer research in Nigeria

The African Research Group for Oncology (ARGO) was formed in 2013 to undertake methodologically rigorous cancer research in Nigeria, and to strengthen cancer research capacity in the country through training and mentorship of physicians, scientists, and other healthcare workers. Here, we describe how ARGO's work in colorectal cancer (CRC) has evolved over the past decade. This includes the consortium's scientific contributions to the understanding of CRC in Nigeria and globally and its research capacity-building program.

EpCAM expression negatively regulates E-cadherin function in colorectal carcinomas

Background

This study aimed to characterise epithelial cell adhesion molecule (EpCAM) expression patterns in colorectal carcinomas (CRC) from Nigerian patients, its association with E-cadherin and tumour characteristics, to forecast patient selection for anti-EpCAM therapy among whom no data existed previously.

Methods

Tissue microarray blocks of formalin-fixed and paraffin-embedded CRC tissues, with their non-cancer margins of resection, were sectioned and stained with EpCAM and E-cadherin primary antibodies. Scoring for antibody staining was done semiquantitatively by combining staining proportion and intensity. The outcome was correlated with patient age, gender and tumour histological parameters with p ≤ 0.05 regarded as statistically significant.

Results

Sixty-three carcinoma tissues had staining status for the two markers and were included in this study. Of these, 36 (57.1%) showed positive EpCAM expression (immunoscore ≥3) out of which 83% (30/36 positive cases) were overexpressed (combined immunoscore ≥4) while 12 (19%) tissues were positive for E-cadherin. Non-tumour margins of resection tissues showed less EpCAM positivity in 24% (6/25) of histospots. The difference in staining between tumour and non-tumour margin tissues with EpCAM was significant (p < 0.001). Also, EpCAM overexpression was significantly associated with reduced E-cadherin (p < 0.035) expression in tumour cells. Tumour extent within the gut wall was equal (50% each) for early and late pT stages among EpCAM overexpressing tumours but two-thirds (8/12) of cases expressing E-cadherin had later pT stage paradoxically, while distant metastasis was negligible among tumours bearing both markers. Also, tumours overexpressing EpCAM had significant association with tumour-associated lymphocytes (p < 0.02 each).

Conclusion

CRC in this study preferentially overexpress EpCAM over E-cadherin whose strong cell-cell contact inhibitory role is weakened even when expressed, resulting in further local tumour spread. This, and the observed immune response, supports targeted therapy among eligible patients.

Epidemiology and genetics of early onset colorectal cancer—African overview with a focus on Ethiopia

Colorectal cancer (CRC) is a common cause of cancer-related death worldwide, with high rates of late diagnosis and increased mortality in sub-Saharan Africa. Furthermore, there is an alarming uptrend in the incidence of early onset colorectal cancer (EOCRC) across the globe, thus necessitating the need for early screening in general and special populations. There is, however, limited data available on the incidence and genetic characteristics of EOCRC from resource-poor countries, particularly Africa. Moreover, there is lack of clarity if recommendations and mechanisms proposed based on data from resource-rich countries applies to other regions of the world. In this review, we appraise the literature on EOCRC, its overall incidence, and genetic components as it pertains to sub-Saharan Africa. In addition, we highlight epidemiologic and epigenetic findings of our EOCRC cohort in Ethiopia.

Evaluation of the preventive potential of graded dietary inclusion of Hyphaene thebaica (Linn) fruit in rat model of colon carcinogenesis

The preventive effect of Hyphaene thebaica fruit in colon carcinogenesis was evaluated in Wistar rats at 0, 2.5, 5 and 10% inclusion rates for twelve weeks with concomitant 72-h intra-rectal N-methyl-N-nitrosourea (MNU) instillations. Indices of antioxidant status and carcinogenesis were analyzed using spectrophotometric, ELISA, histological and immunohistochemical techniques. The fruit protected against lipid peroxidation and level of early biomarkers of colon carcinogenesis, accompanied by decrease in some endogenous antioxidant enzymes functionality. It also prevented colon tissues against MNU-induced severe inflammations and damage to the mutL-homolog 1 (MLH1) gene. There was significant negative correlation between endogenous antioxidant enzyme activities and carcinoembryonic antigen (CEA) as well as lipid peroxidation, but relationship between total polyphenols and percentage expression of MLH1 proteins as well as endogenous antioxidant enzyme activities was positive. These results validate the folkloric use of H. thebaica fruit in the management of colorectal disorders. PRACTICAL APPLICATIONS: Hyphaene thebaica fruit which is widely consumed in northern Nigeria and other countries of sub-Saharan Africa is rich in fiber and antioxidant polyphenols. These two classes of compounds have demonstrated capacity to prevent colorectal cancer and cancer of other sites. Therefore, the validated protective Hyphaene thebaica fruit suggests that it can be processed for inclusion in beverages/diets as functional foods for prevention and management of colorectal disorders.

Drinking Water Source, Chlorinated Water, and Colorectal Cancer: A Matched Case-Control Study in Ethiopia

BACKGROUND

There is no study conducted on the association between disinfection byproducts (DBPs) in chlorinated drinking water and colorectal cancer (CRC) in Ethiopia. Therefore, this study aimed to determine the relation between chlorine based DBPs in drinking water and CRC in Addis Ababa, Ethiopia.

METHODS

A facility based matched case control study was conducted involving 224 cases and 448 population controls from June 2020 to May 2021. Cases were defined as histologically confirmed CRC cases. Cases were matched with controls by residence, age, and sex using frequency and individual matching. Geocoding of cases, health facility, and georeferencing of controls were carried out. Data was collected using a pretested structured questionnaire. Pearson Chi square and Fisher's exact tests were employed to assess associations. Stratified analysis was used to detect confounding factors and effect modification. A multivariable conditional logistic regression was used to identify risk factors of CRC.

RESULTS

Of 214 CRC cases, 148 (69.2%) used chlorinated water whereas out of 428 controls 161 (37.6%) used chlorinated water. In the final regression model, drinking chlorinated surface water (adjusted matched odds ratio [adjusted mOR] = 2.6; 95% CI 1.7-4.0), history of swimming (adjusted mOR = 2.4; 95% CI 1.4-4.1), years at the place of current residence (adjusted mOR = 1.5; 95% CI 1.1-2.2), hot tap water use for showering (adjusted mOR; 3.8 = 95% CI 2.5-5.9) were significantly associated with CRC. The stratified analysis confirmed that smoking and meat ingestion were not effect modifiers and confounders.

CONCLUSION

Drinking chlorinated water for extended years is a significant risk factor for CRC in Addis Ababa, Ethiopia. In addition, hot tap water use for showering, and swimming history are risk factors for CRC. This information is essential to design integrated interventions that consider chlorination by-products and exposure routes toward the prevention and control of CRC in Ethiopia. Initiating alternative methods to chlorine disinfection of drinking water is also essential.

Fecal Immunochemical Test as a Screening Method for Colorectal Cancer in University College Hospital Ibadan, Nigeria

PURPOSE

Colorectal cancer (CRC) is a disease of public health importance because of the increasing incidence of the disease and presentation in advanced stage of the disease in Western Africa. CRC is amenable to screening because of the long course of premalignant lesions before final development of the disease. Despite this, the practice of CRC screening is inadequate at the sites in this study. The fecal immunochemical test (FIT) is one of the recommended noninvasive methods for CRC screening. It has a sensitivity of 96%, specificity of 90%, and an overall accuracy of 95%. We aimed to determine the practicability of FIT for CRC screening in patients aged 40 to 75 years who attended primary care clinics in the University College Hospital, Ibadan, Nigeria.

PATIENTS AND METHODS

A total of 422 patients selected by systematic random sampling were recruited and offered free FIT screening. Participants with a positive finding had additional GI examination, including a digital rectal examination, proctoscopy, and colonoscopy, if no lesion was biopsied during proctoscopy.

RESULTS

The mean (± standard deviation) age of the respondents was 62 ± 9.61 years. The prevalence of a positive FIT in the study was 10.1%. The FIT was not completed by 3.8% of patients, and the rate of completion of additional evaluation after a positive FIT reduced as the investigations became invasive, with 36.8% and 71.1% noncompletion rates for proctoscopy and colonoscopy, respectively.

CONCLUSION

A FIT-based screening for age and risk-appropriate patients is practical in this environment, where the capacity and acceptability of colonoscopy are limited.

Cyclooxygenase-2 expression in colorectal carcinoma, adenomatous polyps and non-tumour bearing margins of resection tissues in a cohort of black Africans

Background

Emerging data suggest a negative role of cyclooxygenase-2 (COX-2) in colorectal carcinomas (CRC). Investigating this in developing communities such as ours helps to contribute to existing understanding of these lesions.

Methods and findings

Formalin-fixed paraffin-embedded CRC colectomy tissues and their corresponding non-tumour margins of resected tissues were sectioned and stained with COX-2 antibody. Adenomatous polyp tissues from non-cancer bearing individuals were similarly processed for comparison. COX-2 expression was scored for percentage (< 5% = 0; 6%-25% = 1; 26%-50% = 2; 51%-75% = 3; 76%-100% = 4) and intensity (no staining = 0; yellow = 2; yellowish-brown = 3, brown = 4). Total immunoscore (percentage + intensity score) ≥ 2 was regarded as positive COX-2 expression. Outcome was statistically evaluated with clinicopathological data to determine COX-2 expression-associated and predictor variables. Ninety-five CRC cases and 27 matched non-tumour tissues as well as 31 adenomatous polyps met the inclusion criteria. Individuals with CRC had a mean age of 56.1 ± 12.6 years while those with adenomatous polyps had a median age of 65 years (range 43–88). COX-2 was differentially overexpressed in CRCs (69/95; 72.6%) and in adenomatous polyps (17/31; 54.8%) than in non-tumour tissues 5/27 (18.5%); p < 0.001). The difference in COX-2 expression between CRC and polyps was non-significant (p > 0.065). Tumour grade, advanced pT-stage, tumour-infiltrating lymphocytes, and dirty necrosis were also significantly associated with COX-2 expression (p < 0.035; 0.043, 0.035 and 0.004, respectively). Only dirty necrosis and Crohns-like lymphocytic aggregates predicted COX-2 expression (p < 0.05).

Conclusion

This study showed a progressive increase in COX-2 expression from normal to adenomatous polyp and CRC tissues, this being associated with poorer prognostic indicators. Although COX-2 appears early in CRC, it may play a secondary role in promoting tumour growth and invasiveness.

Demographic, clinical and pathological characterisation of patients with colorectal and anal cancer followed between 2013 and 2016 at Maputo Central Hospital, Mozambique

Purpose

The aim of this study was to investigate colorectal cancer (CRC) data and anal cancer data from Maputo Central Hospital (MCH), the largest hospital and a reference for oncological diseases in Mozambique, with the aim of characterising the disease profile in view to define an appropriate control programme.

Methods

MCH records from the Pathology and Surgery Services and MCH Cancer Registry database were assessed to obtain retrospective clinical and pathologic data of patients with CRC or anal cancer admitted to and treated between 13 December 2013 and 23 March 2016.

Results

The female gender was more prevalent (54.8%), even when anal cancers were excluded. Median age was 54 years (20–99). Most patients (51.6%) lived in the city of Maputo. The most common presenting symptom was found to be rectal bleeding. Adenocarcinoma was the most frequent histological type, and the most prevalent anatomical site was the rectum. Most of the cases were diagnosed at MCH in advanced stages. Colostomy was the most frequent surgical procedure and performed in 38.7% of the patients. Most cases of anal cancer occurred in human immunodeficiency virus-infected patients. Most patients had a poor prognosis due to advanced stage at first diagnosis.

Conclusion

We observed an increase in cases of CRC and anal cancer in Mozambique and mostly diagnosed at advanced stages, which anticipates a dismal prognosis. Our data supports the urgent need of a comprehensive public health programme dedicated to solving this growing concern.

Clinicopathological spectrum of colorectal cancer among the population of the KwaZulu-Natal Province in South Africa

Introduction

the burden of colorectal carcinoma (CRC), once considered rare in Africa, may be changing with the disease being increasingly diagnosed and there is a suggestion that age and race influence tumour behaviour. We sought to describe the clinicopathological spectrum of CRC among the different race and age groups in a South African setting.

Methods

analysis of prospectively collected data from an on-going colorectal cancer database, including demographics, clinical presentation, site, staging and grading on all patients enrolled over an 18-year period.

Results

a total of 2232 patients with CRC were accrued over the study period (Africans, 798; Indians, 890; Coloureds, 104; and Whites, 440). Mean age was 57.7 (SD 14.4) but varied considerably by race (p < 0.001) with Africans being significantly younger. Young adults (aged < 40 years) totalled 305 and older patients (aged > 40 years) totalled 1927. The proportion of young patients (< 40 years old) was 28%, 7%, 9% and 3% among Africans, Indian, Coloured and White patients respectively. There were minimal variations in anatomical sub-site distribution. There was no difference in tumour stage between the various races and between older and young adults. Mucinous differentiation was more common in Africans and in young patients and poor differentiation was more common in African patients. Africans had a significantly lower resection rate compared to the other race groups (p < 0.001). Younger patients had a significantly lower resection rate compared to the older age group (p < 0.001).

Conclusion

African patients were the youngest compared to the other race groups. Mucinous differentiation predominated in Africans and young adults. Poor differentiation predominated in Africans. Resection rate was lower for African patients and in young patients.

PERIOPERATIVE MORBIDITY AND MORTALITY AFTER EMERGENCY AND ELECTIVE COLON AND PROXIMAL RECTAL SURGERY IN IBADAN

OBJECTIVE

While the epidemiology of benign colonic pathologies has not significantly changed in our region, colorectal cancer has steadily increased with a majority of patients presenting with late stage disease particularly large bowel obstruction. This study reviews the outcome of emergency and elective colon and proximal rectal cases with regards to perioperative morbidity and mortality.

SETTING

All patients who had surgery for symptoms of lower gastrointestinal tract disease (caecum and proximal rectum) between January 2008 and January 2018 at University College Hospital, Ibadan were included. Data regarding elective or emergency presentation, peri-operative findings, operative details and postoperative course were recorded prospectively.

RESULTS

Out of the 1618 patients with symptoms, 817 were operated on as emergencies (38.1%) and electives (61.9%). The median age of patients who had emergency and elective surgery were 56 (33-81) and 59 (27-87) respectively (p-0.05). Right hemicolectomy (152; 18.6%) was the commonest procedure, followed by anterior resection (115; 14.1%) and colostomy (114; 13.9%). Overall morbidity was 13.7% (elective 4.2%; emergency 9.5%), while mortality was 6.8% (elective 2.1%; emergency 4.7%). The commonest morbidities were superficial surgical site infection (SSSI) and wound dehiscence. Bowel perforation or gangrene was the most significant predictor of mortality.

CONCLUSION

Large bowel obstruction complicated with perforation and gangrene is a major risk factor for morbidity and mortality in colorectal surgery.

Treatment of colorectal cancer in Sub-Saharan Africa: Results from a prospective Nigerian hospital registry

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer worldwide. Mortality for CRC is improving in high income countries, but in low and middle income countries, rates of disease and death from disease are rising. In Sub-Saharan Africa, the ratio of CRC mortality to incidence is the highest in the world. This study investigated the nature of CRC treatment currently being offered and received in Nigeria.

METHODS

Between April 2013 and October 2017, a prospective study of consecutively diagnosed cases of CRC was conducted. Patient demographics, clinical features, and treatment recommended and received was recorded for each case. Patients were followed during the study period every 3 months or until death.

RESULTS

Three hundred patients were included in our analysis. Seventy-one percent of patients received a recommended surgical operation. Of those that didn't undergo surgery as recommended, 37% cited cost as the main reason, 30% declined due to personal reasons, and less than 5% absconded or were lost to follow up. Approximately half of patients (50.5%) received a chemotherapy regimen when it was recommended, and 4.1% received radiotherapy when this was advised as optimal treatment. With therapy, the median overall survival for patients diagnosed with stage III and stage IV CRC was 24 and 10.5 months respectively. Overall, we found significantly better median survival for patients that received the recommended treatment (25 vs 7 months; P < .01).

CONCLUSIONS

A number of patients were unable to receive the recommended treatment, reflecting some of the burden of untreated CRC in the region. Receiving the recommended treatment was associated with a significant difference in outcome. Improved healthcare financing, literacy, training, access, and a better understanding of tumor biology will be necessary to address this discrepancy.

Demographic and Clinicopathological Patterns of Colorectal Cancer at the National Cancer Institute, Sudan

Background:

Colorectal cancer is a common type of cancer worldwide, including in Sudan. However, few studies have assessed its demographic, clinical and pathological patterns in the Sudanese population.

Objective:

To assess the demographic, clinical and pathological patterns in patients with colorectal cancer at National Cancer Institute, University of Gezira, Sudan.

Methods:

This retrospective, cross-sectional study analyzed the data of all colorectal cancer patients who presented to National Cancer Institute, University of Gezira, between January 2016 and December 2017. National Cancer Institute, University of Gezira, is one of the two National Cancer Institutes in Sudan and receives patients from across Sudan. The demographic, clinical and pathological information were extracted from the patients’ files.

Results:

A total of 163 colorectal cancer patients who presented to National Cancer Institute during the study period and met the inclusion criteria were included in this study. Most patients were aged >40–69 years (58.8%), were male (53.4%) and from Central Sudan (65.6%). About 44% of the patients were diagnosed 6–12 months from the disease onset and 26.8% after >12 months. Change in bowel habits (51.5%), rectal bleeding (42.3%) and abdominal pain (32.5%) were the most common clinical presentations. About 58% of the patients did not undergo per rectal examination during their initial presentation. Rectum was the most common site of tumor (58.9%), and the majority of patients had Grade I adenocarcinoma (50.3%). Duke's Class B (38%) and Class C (31%) were the most common stages of the patients’ tumor, and signet ring carcinoma was found in 4.9% of the patients.

Conclusion:

This study found that in Sudan, colorectal cancer patients most commonly present late after the onset of symptoms, with an advanced stage and aggressive pattern as well as the proportion of younger patients is high. Further, per rectal examination is often not performed during the initial presentation.

A Rural-Urban Comparison of Knowledge, Risk- Factors and Preventive Practices for Colorectal Cancer among Adults in Lagos State

Objective:

To assess and compare the knowledge, risk-factors and preventive practices for colorectal cancer among adults in Lagos State.

Material and methods:

This was a cross-sectional comparative study conducted among 607 respondents selected from one rural (Ikorodu) and one urban (Surulere) LGA using a multistage sampling technique. Data were collected using a pre-tested questionnaire administered by trained research assistants between April and September 2017.Data was analyzed using Epi-info statistical software version 3.5.1. Univariate and bivariate analysis was carried out and -p values of ≤0.05 were considered statistically significant.

Results:

Respondents’ knowledge of colorectal cancer was generally low, (rural-78.2%, urban- 62.2%, p<0.001). Urban respondents were significantly more knowledgeable than their rural counterparts (rural- 21.8%, urban- 37.8%, p<0.001). The presence of CRC risk-factors were higher among urban respondents (urban-49.3%, rural-42.6%, p= 0.09), however this difference was not statistically significant. Preventive practices were generally poor in both groups, although more (18.1%) urban respondents significantly took preventive actions against CRC compared with rural (6.9%) respondents, (p<0.001).Increasing levels of education were significantly associated with higher knowledge level in both groups (p≤0.05).

Conclusion:

The level of knowledge of colorectal cancer was generally poor in both groups but significantly poorer among rural respondents. The presence of known risk- factor was higher among urban respondents while preventive practices were poor in both groups.

Assessment of risk factors affecting mortality in patients with colorectal cancer

INTRODUCTION

The most important risk factors for colorectal cancer are age, high ASA score, anemia, low albumin, tumor stage, histopathological properties, tumor's relationship with adjacent tissues, positivity of surgical borders and timing of the surgical procedure.

AIM

To determine possible risk factors for mortality in patients undergoing colorectal cancer surgery.

MATERIAL AND METHODS

The medical records of 101 consecutive patients who underwent colorectal cancer surgery at the Department of Surgery, Sutcu Imam University Faculty of Medicine, Kahramanmaras, Turkey between January 2008 and November 2015 were retrospectively reviewed. The patients were divided into two groups: surviving (n = 76) and deceased (n = 25) groups. The groups were compared in terms of several demographic, clinical, biochemical, and histopathological parameters. In addition, risk factors for mortality were analyzed with multivariate analysis. SPSS 22.2, PAST 3, and MedCalc 14 software packages were used for statistical analyses.

RESULTS

The surviving and deceased groups significantly differed with respect to age (p = 0.001), hemoglobin (p = 0.001), lymph node positivity (p = 0.009), positive lymph node/total lymph node ratio (p = 0.012), thrombocyte count (p = 0.047), lymphovascular invasion (p = 0.028), urgency of admission (emergency/elective) (p = 0.036), and postoperative carcinoembryonic antigen (CEA) level (p = 0.002). A receiver operating characteristics curve was drawn to determine the cut-off values of various parameters including age (63), hemoglobin (12.8), node positivity (3), positive/total lymph node ratio (0.435) and thrombocyte count (308), with age (p < 0.001), hemoglobin (p < 0.001), node positivity (p = 0.025) and positive/total lymph node ratio (p = 0.024) being significantly different. A multivariate analysis revealed that age (p = 0.049), hemoglobin (p = 0.045), and positive/total lymph node ratio (p = 0.025) were independent risk factors for mortality.

CONCLUSIONS

This study shows that older age, lower hemoglobin level, and high positive/total lymph node ratio were independent risk factors for mortality among colorectal cancer patients.

The shifting epidemiology of colorectal cancer in sub-Saharan Africa

The perception that colorectal cancer is rare in sub-Saharan Africa is widely held; however, it is unclear whether this is due to poor epidemiological data or to lower disease rates. The quality of epidemiological data has somewhat improved, and there is an ongoing transition to western dietary and lifestyle practices associated with colorectal cancer. The impact of these changes on the incidence of colorectal cancer is not as evident as it is with other non-communicable diseases such as diabetes. In this Viewpoint, we discuss the epidemiology of colorectal cancer in sub-Saharan Africa. Colorectal cancer in this region frequently occurs at an early age, often with distinctive histological characteristics. We detail the crucial need for hypothesis-driven research on the risk factors for colorectal cancer in this population and identify key research gaps. Should colorectal cancer occur more frequently than assumed, then commensurate allocation of resources will be needed for diagnosis and treatment.

THE DISTRIBUTION, HISTOLOGIC PROFILE AND CLINICAL PRESENTATION OF GASTROINTESTINAL MALIGNANCIES IN LAGOS, NIGERIA

BACKGROUND

Gastrointestinal malignancies have continued to record higher incidence and therefore pose significant public health burden in terms of morbidity and mortality.

AIM

To evaluate the sociodemographic, histologic and clinical distribution of patients with gastrointestinal malignancies diagnosed between July 2009 and March 2016.

SETTING

Lagos University Teaching Hospital, Idi-Araba, south-west Nigeria.

METHODOLOGY

Using a retrospective study design, all the patients with histologic diagnosis of gastrointestinal malignancies were recruited and their bio-data, clinical, histologic and treatment data were extracted from their hospital records.

RESULTS

Of the 106 cases of gastrointestinal malignancies in this study, the age range was 30-82 years with a mean of 55.9±13 years and a peak age bracket of 50-59 years; the male/female ratio was 1.2:1. The most common sites were colorectum (79.3%), stomach (7.6%), anus (6.6%), liver (4.7%), and pancreas (0.9%). Adenocarcinoma was the most common histologic subtype (89.62%), followed by squamous cell carcinoma (2.83%) and gastrointestinal stromal tumors (1.89%). The most common complaints were abdominal pain (54.7%), constipation (38.7%), palpable abdominal swelling/masses (35.9%), bleeding (33.0%), and weight loss (17.0%). The tumors were treated with chemotherapy, surgery, and radiotherapy, either singly or in combination, in 97.2%, 83.0%, and 30.2% respectively.

CONCLUSION

In this study, colorectal cancers are still the most prevalent type of gastrointestinal malignancies with a male preponderance, and individuals between 40-59 years are at greater risk. The significant involvement of individuals who constitute the bulk of the workforce and are the most productive labor in the country points at the need to develop strategies aimed at reducing the incidence of gastrointestinal malignancies.

Clinicopathologic review of polyps biopsied at colonoscopy in Lagos, Nigeria

Introduction

Colorectal polyps are known precursors of colorectal cancers. The increase in utilization of colonoscopy in Nigeria has meant a rise in the recently reported incidence of these lesions. The aim of this study is to evaluate the clinicopathological profile of colorectal polyps biopsied during the inaugural 12 month period of colonoscopy from a private endoscopy suite in Nigeria.

Methods

This is a retrospective review of all the clients who had polyps diagnosed at colonoscopy over a 12 month period (August 2014 –July 2015) at a private endoscopy suite in Lagos, Nigeria. This analysis of prospectively collected data was performed using clinical information from the endoscopy logs and pathology database system of a private endoscopy suite based in Lagos, Nigeria.

Results

A total of 125 colonoscopies were carried out over the stated period. Of these, 14 individuals had a total of 18 polyps- 4 clients (28.6% of the persons with polyps) had two polyps each. The polyp detection rate was 11.2% while the polyp per colonoscopy rate was 14.4%. Of these clients, males were 10 in number; giving a male to female ratio of 2.5:1. Their ages ranged from 37 to 77 years (mean= 57.3 years). The presenting complaint at colonoscopy was hematochezia in 11 (78.6%), new onset constipation in 2 (14.2%) and peri-anal pain in 1 patient (7.1%). The polyps were distributed as follows; 2 (11.1%) in the ascending colon, 1 (5.6%) each in the transverse and descending colons, 8 (44.4%) in the sigmoid colon, 6(33.3%) located in the rectum. Hence, there was left sided (15 of 18= 83.3%) preponderance. Pathologically, tubular (adenomatous) polyp with or without low grade dysplastic changes was diagnosed in 6 of the 18 polyps (giving an adenoma detection rate of 4.8%), 4 (22.2%) were inflammatory polyps, 1 (5.6%) was malignant and another had the rare inflammatory fibroid polyp. Five (27.8%) of the specimens were reported as non-specific colitis.

Conclusion

The study supports the present wisdom that polyps are clearly less prevalent in our environment when compared to the Western world. The increased prevalence with advancing age, in male subjects and of left sided lesions, is also in keeping with previous results from our environment. A case is also advanced for the increased deployment of endoscopy as a tool for the detection of these polyps and ultimately, the reduction of colorectal cancer in our population.

The incidence and histo-pathological characteristics of colorectal cancer in a population based cancer registry in Zimbabwe

BACKGROUND

Data on colorectal cancer (CRC) in sub-Saharan Africa is mainly based on hospital series which suggest low incidence and frequent early onset cancers. This study characterises colorectal cancer in a population-based cancer registry in Zimbabwe.

METHODS

Cases of CRC recorded by the Zimbabwe National Cancer Registry between 2003 and 2012 were analysed. Demographic and pathological characteristics were compared according to ethnicity and age. Trends in age standardised incidence rates (ASR) were determined.

RESULTS

There were 886 and 216 cases of CRC among black Africans and Caucasians respectively, and 26% of the black Africans were younger than 40 years. Signet ring cell carcinomas were more common among black Africans compared to Caucasians (4% vs 1%, p=0.027). ASR increased by 1.9%/year and 3.9%/year among black African males and females respectively.

CONCLUSION

CRC incidence is rising among black Africans and has unique demographic and pathological characteristics.

Colorectal Carcinomas in Uyo City, Southern Geopolitical Zone of Nigeria: A Review of Clinicopathological Characteristics and Literature

Colorectal carcinomas (CRC) were initially thought to be rare in Africa including Nigeria, but recent studies have shown a reverse trend in our environment. This study is aimed to identify the clinical and pathological characteristics of CRC diagnosed between July 2006 and June 2015 in the University of Uyo Teaching Hospital, and a Private Specialist Laboratory, Uyo, Akwa Ibom State, Nigeria. All histological diagnosed cases of CRC seen in the two laboratories (University teaching and a private facility) in Uyo, Akwa-Ibom state, Nigeria during the study period were retrieved noting their bio-data, pathological and clinical variables. A total of 45 patients of age range 26-80 years with a mean of 55.9 years (SD 3.9) and a male to female ratio of 1.4:1 were seen. The two most common age groups affected in CRCs were 61-70 years (28.9%) and 51-60 years (24.4%) respectively. Majority of CRC patients were older than 40 years (86.7%) with identifiable predisposing factors being tubulo-villous adenoma (4 cases, 8.8%), villous adenoma (2 cases 4.4%), polyposis syndromes (2 cases, 4.4%) and schistosomiasis (1 case, 2.2%). Features of large intestinal obstruction were the most common presenting symptom of CRC (53.3%). Rectal bleeding, alteration in bowel habit and fecal incontinence were other symptoms, accounting for 33.3%, 8.9% and 4.4% of cases respectively. Left-sided CRCs were commoner (68.9%) with the majority appearing as annular-constricting type macroscopically (60.0%). Recto-sigmoid region was the preponderant site involved in CRC (29 cases, 64.5%). Adenocarcinoma (84.4%) was the most frequent histological subtype. Mucinous carcinoma, signet ring carcinoma and carcinoid tumor were other histologic subtypes seen in 8.9, 4.4 and 2.2% of cases respectively. The 22.0% of CRC patients presented at advanced stages of the disease. It can be concluded that majority of CRC patients were older than 40 years (86.7%) with features of intestinal obstruction (53.3%) and adenocarcinoma (84.4%) being the predominant mode of clinical presentation and histological subtype respectively.

Diagnostic Value of Endorectal Ultrasound in Preoperative Assessment of Lymph Node Involvement in Colorectal Cancer: a Meta-analysis

BACKGROUND

Nodal invasion by colorectal cancer is a critical determinant in estimating patient survival and in choosing appropriate preoperative treatment. The present meta-analysis was designed to evaluate the diagnostic value of endorectal ultrasound (EUS) in preoperative assessment of lymph node involvement in colorectal cancer.

MATERIALS AND METHODS

We systematically searched PubMed, Web of Science, Embase, and China National Knowledge Infrastructure (CNKI) databases for relevant studies published on or before December 10th, 2014. The sensitivity, specificity, likelihood ratios, diagnostic odds ratio (DOR) and area under the summary receiver operating characteristics curve (AUC) were assessed to estimate the diagnostic value of EUS. Subgroup analysis and meta-regression were performed to explore heterogeneity across studies.

RESULTS

Thirty-three studies covering 3,016 subjects were included. The pooled sensitivity and specificity were 0.69 (95%CI: 0.63-0.75) and 0.77 (95%CI: 0.73-0.82), respectively. The positive and negative likelihood ratios were 3.09 (95%CI: 2.52-3.78) and 0.39 (95%CI: 0.32-0.48), respectively. The DOR was 7.84 (95%CI: 5.56-11.08), and AUC was 0.80 (95%CI: 0.77-0.84).

CONCLUSIONS

This meta-analysis indicated that EUS has moderate diagnostic value in preoperative assessment of lymph node involvement in colorectal cancer. Further refinements in technology and diagnostic criteria are necessary to improve the diagnostic accuracy of EUS.

A comparison of colorectal cancer in Nigerian and North American patients: is the cancer biology different?

BACKGROUND

Of the 24 million people predicted to have cancer by 2050, 70% will live in low- and middle-income countries (LMIC). As a result, cancer care is becoming a priority for health care systems in West Africa. This study compares the presentation and pattern of spread of colorectal cancer (CRC) observed in a hospital in West Africa with that of a North American referral center.

METHODS

Data on all adults presenting with CRC at a hospital in Nigerian patients (West Africa; 1990-2011) and all adults with stages III or IV CRC at a specialty hospital in (New York City, New York, North America; 2005-2011) were examined retrospectively. Demographic data, stage of disease, site of metastasis, and survival were compared.

RESULTS

There were 160 patients identified in West Africa and 1,947 patients identified in North America. Nigerian patients were younger (52 vs 59 years; P < .01) and presented with a later stage of disease (58% stage IV vs 47%; P < .01). Site of disease presentation was different between West African and North American patients (P < .01); 2.2% of West African patients presented with liver metastases only compared with 48.1% of North American patients. Conversely, 61.3% of patients in West Africa presented with peritoneal metastases only compared with 5.4% in North America. Overall survival stratified by stage at presentation (III/IV) showed worse prognosis for patients in either stage subgroup in Nigeria than North America.

CONCLUSION

We found differences in the presentation, metastatic pattern, and outcomes of CRC in Nigerian (West Africa) when compared with New York City (North America). Late detection and differential tumor biology may drive the differences observed between the sites. Future studies on early CRC detection and on tumor biology in LMIC will be critical for understanding and treating CRC in this region.

Clinicopathological patterns and challenges of management of colorectal cancer in a resource-limited setting: a Tanzanian experience

Background

Colorectal cancer is one of the most common cancers worldwide and its incidence is reported to be increasing in resource-limited countries, probably due to the acquisition of a western lifestyle. However, information regarding colorectal cancer in Tanzania and the study area in particular is limited. This study was conducted in our local setting to describe the clinicopathological pattern of colorectal cancer and highlight the challenging problem in the management of this disease.

Methods

This was a retrospective study of histologically confirmed cases of colorectal cancer seen at Bugando Medical Center between July 2006 and June 2011. Data were retrieved from patients’ files and analyzed using SPSS computer software version 17.0.

Results

A total of 332 colorectal cancer patients were enrolled in the study, representing 4.7% of all malignancies. Males outnumbered females by a ratio of 1.6:1. The median age of patients at presentation was 46 years. The majority of patients (96.7%) presented late with advanced stages. Lymph node and distant metastasis at the time of diagnosis was recorded in 30.4% and 24.7% of cases, respectively. The rectosigmoid region was the most frequent anatomical site (54.8%) involved and adenocarcinoma (98.8%) was the most common histopathological type. The majority of adenocarcinomas (56.4%) were moderately differentiated. Mucinous and signet ring carcinomas accounted for 38 (11.6%)and 15 (4.6%) patients, respectively. Three hundred and twenty-six (98.2%) patients underwent surgical procedures for colorectal cancer. Only 54 out of 321 (16.8%) patients received adjuvant treatment. Postoperative complication and mortality rates were 26.2% and 10.5%, respectively. The overall median duration of hospital stay was 12 days. Only nine out of 297 survivors (3.0%) were available for follow-up at the end of 5 years. Cancer recurrence was reported in 56 of 297 survivors (18.9%). Data on long-term survival were not available as the majority of patients were lost to follow-up.

Conclusions

Colorectal cancer is not uncommon in our environment and shows a trend towards a relative young age at diagnosis and the majority of patients present late with advanced stage. There is a need for screening of high-risk populations, early diagnosis and effective cost-effective treatment and follow-up to improve outcome of these patients.

Miniprobe endoscopic ultrasonography has limitations in determining the T stage in early colorectal cancer

Background/Aims

Mini-probe endoscopic ultrasonography (mEUS) is a useful diagnostic tool for accurate assessment of tumor invasion. The aim of this study was to estimate the accuracy of mEUS in patients with early colorectal cancer (ECC).

Methods

Ninety lesions of ECC underwent mEUS for pre-treatment staging. We divided the lesions into either the mucosal group or the submucosal group according to the mEUS findings. The histological results of the specimens were compared with the mEUS findings.

Results

The overall accuracy for assessing the depth of tumor invasion (T stage) was 84.4% (76/90). The accuracy of mEUS was significantly lower for submucosal lesions compared to mucosal lesions (p=0.003) and it was lower for large tumors (≥2 cm) (p=0.034). The odds ratios of large tumors and submucosal tumors affecting the accuracy of T staging were 3.46 (95% confidence interval [CI], 1.05 to 11.39) and 6.25 (95% CI, 1.85 to 25.14), respectively. When submucosal tumors were combined with large size, the odds ratio was 14.67 (95% CI, 1.46 to 146.96).

Conclusions

The overall accuracy of T stage determination with mEUS was considerably high in patients with ECC; however, the accuracy decreased when tumor size was >2 cm or the tumor had invaded the submucosal layer.

Estimating the incidence of colorectal cancer in Sub-Saharan Africa: A systematic analysis

Background

Nearly two–thirds of annual mortality worldwide is attributable to non–communicable diseases (NCDs), with 70% estimated to occur in low– and middle–income countries (LMIC). Colorectal cancer (CRC) accounts for over 600 000 deaths annually, but data concerning cancer rates in LMIC is very poor. This study analyses the data available to produce an estimate of the incidence of colorectal cancer in Sub–Saharan Africa (SSA).

Methods

Data for this analysis came from two main sources: a systematic search of Medline, EMBASE and Global Health which found 15 published data sets, and an additional 42 unpublished data sets which were sourced from the IARC and individual cancer registries. Data for case rates by age and sex, as well as population denominators were extracted and analysed to produce an estimate of incidence.

Results

The crude incidence of CRC in SSA for both sexes was found to be 4.04 per 100 000 population (4.38 for men and 3.69 for women). Incidence increased with age with the highest rates in Southern Africa, particularly in South Africa. The rates of CRC in SSA were much lower than those reported for high–income countries.

Conclusion

Few health services in SSA are equipped to provide timely diagnosis and treatment of cancer in SSA. In addition, data collection systems are weak, meaning that the available statistics may underestimate the burden of disease. In order to improve health care services it is vital that accurate measurements of disease burden are available to policy makers.

Nutritional status of older persons presenting in a primary care clinic in Nigeria

The study objective was to determine the nutritional status and its association with sociodemographic characteristics and health complaints of older persons presenting at the General Outpatients Department (GOPD) Clinic of University College Hospital (UCH), Ibadan, Nigeria. A cross-sectional descriptive design was used to select 500 consecutively presenting participants aged 60 years and older between September and December, 2009. The Mini-Nutritional Assessment (MNA) tool and body mass index were used to assess undernutrition and overweight, respectively. The prevalence of nutritional problems was 61.9% (undernutrition = 7.8% and overweight = 54.1%). Being unmarried (P < 0.001), engagement in a job after the age of 60 years (P < 0.001), constipation (P = 0.009), rectal bleeding (P = 0.008), and oral problems (mouth, teeth, and tongue) were significantly (P < 0.001) associated with undernutrition. Younger age (P = 0.050) and female gender (P = 0.011) were significantly associated with being overweight. Logistic regression analysis showed being unmarried OR = 1.355 (95%CI 1.075-1.708) to be the most important factor for the development of undernutrition. The high prevalence of nutritional problems in this study underscores the need for intervention in this population. Correlation analysis (Pearson's) showed a positive association between BMI and MNA scores (r = 0.152, P = 0.001).

Colorectal cancer and pollution

The incidence of colorectal carcinoma is increasing in young patients, in contrast to the well established wisdom that it is exclusively diagnosed in patients older than 40 years. In this survey, we examined all possible risk factors, and we recommend a number of measures for early detection in young patients who are at risk of developing this malignant tumor.

Colorectal carcinoma: Importance of colonic environment for anti-cancer response and systemic immunity

The intestinal environment is considered to play an important role both in colorectal tumor development and in the evolution and modulation of mucosal immunity. Studies in animals reared in germ-free (GF, without any intestinal microflora) versus conventional (CV, with regular microflora in bowel) conditions can aid in clarifying the influence of bacteria on carcinogenesis and anti-cancer immune responses in situ. The lower incidence of colon cancers and better immunological parameters in GF animals versus CV ones after chemically-induced carcinogenesis raises questions about specific characteristics of the immunological networks in each respective condition. Different levels of tolerance/regulatory mechanisms in the GF versus CV animals may influence the development of immune responses not only at the level of mucosal, but also at the systemic, immunity. We hypothesize that GF animals can better recognize and respond to evolving neoplasias in the bowel as a consequence of their less-tolerogenic immunity (i.e., due to their more limited exposure to antigens to become tolerated against at the intestinal level). In this paper, we review the role of bacteria in modulating gut environment and mucosal immunity, their importance in cancer development, and aspects of immune regulation (both at local and systemic level) that can be modified by bacterial microflora. Lastly, the use of GF animals in comparison with conventionally-raised animals is proposed as a suitable and potent model for understanding the inflammatory network and its effect on cancer immunity especially during colorectal cancer development.

Familial Adenomatous Polyposis with Synchronous Invasive Colonic Carcinomas and Metastatic Jejunal Adenocarcinoma in a Nigerian Male

Familial adenomatous polyposis is rare. Three cases were previously reported in Nigeria. An intriguing feature of this case is an ulcerated jejunal carcinoma which was metastatic rather than synchronous carcinoma. This patient presented with partial large bowel obstruction and the pathological analysis revealed 4 invasive adenocarcinomas, 3 in the colon and 1 in the jejunum (Dukes stage D). Palliative pancolectomy and jejunal tumour resection with chemotherapy was offered to him. He died eight months after surgery from disease progression. The challenges of managing a hereditary cancer syndrome in a resource poor country are highlighted.