Colorectal cancer burden and trends in a South Asian cohort: experience from a regional tertiary care center in Sri Lanka

Objective

Colorectal cancer (CRC) burden is increasing in the south Asian region due to the changing socio-economic landscape and population demographics. There is a lack of robust high quality data from this region in order to evaluate the disease pattern and comparison. Using generalized linear models assuming Poisson distribution and model fitting, authors describe the variation in the landscape of CRC burden along time since 1997 at a regional tertiary care center in Sri Lanka.

Results

Analyzing 679 patients, it is observed that both colon and rectal cancers have significantly increased over time (pre 2000—61, 2000 to 2004—178, 2005 to 2009—190, 2010 to 2014–250; P < 0.05). Majority of the cancers were left sided (82%) while 77% were rectosigmoid. Over 25% of all CRC were diagnosed in patients less than 50 years and the median age at diagnosis is < 62 years. Increasing trend is seen in the stage at presentation while 33% of the rectal cancers received neoadjuvant chemoradiation. Left sided preponderance, younger age at presentation and advanced stage at presentation was observed. CRC disease pattern in the South Asian population may vary from that observed in the western population which has implications on disease surveillance and treatment.

A rare presentation of an acute abdomen: an ileal diverticular perforation

Background

This case report highlights the value of prompt intervention of diagnostic laparoscopy in a patient suspects of having an acute abdomen due to an intestinal perforation, where there is a limitation of performing Contrast Enhanced Computed Tomography of abdomen. A previously healthy young adult presenting with an acute abdomen due to a spontaneous ileal perforation, without any associated risk factors is a rare clinical entity in a developing country. Therefore, entertaining an early diagnosis will possibly prevent a fatal consequence.

Case presentation

A male patient, 29 years old, recently diagnosed as a young hypertensive without any associated factors, currently on antihypertensive treatment, was admitted to our hospital presenting with an acute severe abdominal pain. During initial assessment, the patient was febrile (101 °F), ill looking, tachycardic (pulse rate 121 bpm) with rapid shallow breathing. Abdominal examination reviled diffuse guarding and rigidity, more severe on right iliac fossa. Following history and clinical examination probable clinical diagnosis was made as an acute appendicitis with perforation. However, ultrasonography was found to have normal appendix. Contrast Enhanced Computed Tomography was not performed as a subsequent investigation because of the impairment of renal functions of this patient. Though, non-contrast CT would have been ascertained more diagnostic yield, given the critically ill status of this patient we decided to perform urgent diagnostic laparoscopy. It reviled pus in several abdominal cavities and dense adhesions. Therefore, the procedure was converted to a laparotomy and found to have an ileal perforation with diffuse peritoneal contamination. Diseased ileal segment was resected and anastomosed. Followed by peritoneal lavage.

Conclusion

Ileal perforation due to diverticular disease in a healthy young adult is rare. This case report highlights the importance of considering this clinical entity as a differential diagnosis, the value of early diagnostic laparoscopy, especially in clinical settings with limitations to CT scan, since late diagnosis can give rise to fatal outcome.

Intestinal tuberculosis masquerading as difficult to treat Crohn disease: a case report

Background

Crohn disease has low prevalence in Sri Lanka while compared to the West, while intestinal tuberculosis is common in the region. Since clinical, endoscopic and investigation features of Crohn disease overlap with intestinal tuberculosis, differentiating these two conditions becomes a dilemma for the clinician in the intestinal tuberculosis endemic setting.

Case summary

An 18-year old Sri Lankan Muslim female presented with chronic abdominal pain and weight loss. Colonoscopy revealed an ulcerated ileocaecal valve and a terminal ileal stricture. Biopsy confirmed Crohn disease with no supportive features to suggest intestinal tuberculosis. Despite treatment with adequate immunosuppression she failed to improve and underwent a limited right hemicolectomy and terminal ileal resection. Histology confirmed intestinal tuberculosis and she made full recover with 6 months of anti-tuberculosis treatment.

Conclusion

This case illustrates the importance of reviewing the diagnosis to include intestinal tuberculosis in an endemic setting, when already diagnosed Crohn disease is treatment refractory.

Total number of lymph nodes harvested is associated with better survival in stages II and III colorectal cancer

BACKGROUND

Lymph node status is important in staging colorectal cancer (CRC). Presence of metastatic nodes differentiates stage III from stage II. The role of adjuvant therapy is still unclear in stage II CRC. Inadequate node sampling may result in inaccurate staging.

METHOD

Records of 131 patients with stages II and III CRC who underwent curative resection, having five or more lymph nodes harvested from the specimen, were prospectively followed up and analyzed. The Kaplan-Meier method was used to analyze survival, based on groups of serially ascending values of lymph nodes harvested. Regression analysis was performed by Cox proportional hazards ratio model with right-censored CRC survival data at a 10 % significance level. The effect of nodal harvest on survival was adjusted for age, sex, preoperative carcinoembryonic antigen (CEA) level, neoadjuvant chemoradiation, pathological tumor stage, histological type, differentiation, margin positivity, angioinvasion, perineural invasion, and lymphovascular infiltration.

RESULTS

The total population showed improved survival with 14 or more nodes harvested (p= 0.005). For both rectal (n= 83; p= 0.03) and colon cancers (n= 46; p= 0.08), most significant survival benefits were seen with over 14 nodes harvested, irrespective of the stage. With multiple regression analysis, advanced age (p= 0.003), male sex (p= 0.017), lymphovascular infiltration (p= 0.015), and preoperative CEA levels (p= 0.096) were found to be other significant factors. The lymph node effect remained significant (HR = 0.19, p= 0.004) after adjusting for the above factors.

CONCLUSION

A lymph node harvest of 14 or more resulted in better survival outcome from CRC in this population. Staging of the disease could be accurate with increased nodal harvesting.

Subclinical mucosal inflammation in diarrhea-predominant irritable bowel syndrome (IBS) in a tropical setting

BACKGROUND AND AIMS

There is evidence for low-grade inflammation in the pathophysiology of post-infectious irritable bowel syndrome (IBS). We assessed the degree of subclinical intestinal mucosal inflammation in diarrhea-predominant IBS (IBS-D) in a tropical setting.

MATERIAL AND METHODS

In a prospective study over 1 year, we investigated 49 patients with IBS-D (cases; median age 34 years (range 18-59); M:F 36:13), diagnosed on Rome III criteria. 14 individuals with a family history of colon cancer (median age 46.5 years (range 23-56); M:F 6:8) were selected as controls. Stools of cases and controls were tested for calprotectin. During colonoileoscopy, serial biopsies were obtained. Mucosal mast cells, neutrophils, eosinophils and lymphocytes/plasma cell infiltrate were quantified. Tissue expression of IL-8 and IL-10 was assessed in biopsies by semi-quantitative RT-PCR.

RESULTS

A history suggestive of an episode of infectious diarrhea (ID) was present in 16/49 cases and 0/14 controls (p = 0.013). In cases, there were significantly more mucosal mast cells in the ileum and all segments of colon and significantly more eosinophils in the cecum. Tissue expression of IL-8 was significantly higher and IL-10 significantly lower in cases compared with controls (target/standard cDNA ratio, median (range) IL-8: 1.25 (0.75-2) vs. 0.85 (0.63-1.3), p < 0.0001, Mann-Whitney U test; IL-10: 0.33 (0-0.63) vs. 0.55 (0.5-0.7), p < 0.0001). There was a significant inverse correlation between IL-8 and IL-10 expression (Pearson correlation, (-) 0.509; p < 0.01).

CONCLUSION

There was evidence of subclinical intestinal mucosal inflammation in patients with IBS-D. The finding of increased eosinophils is novel, and may be of special relevance to IBS-D in the tropics.

Histopathology reporting in colorectal cancer: a proforma improves quality

AIM

The histopathology report is vital to determine the need for adjuvant therapy and prognosis in colorectal cancer (CRC). Completeness of those in text format is inadequate. This study evaluated the improvement of quality of histopathology reports following the introduction of a template proforma, based on standards set by the Royal College of Pathologists (RCP), UK.

METHOD

Sixty-eight consecutive histopathology reports based on 19 items for rectal cancer (RC) and 15 items for colon cancer (CC) using the proforma were prospectively analysed and compared with results of a previous audit of 82 consecutive histopathology reports in text format. The percentage of reports containing a statement for each data item for both series was compared using the Normal test for difference between two proportions. Completeness of each report was assessed and a percentage score (percentage completeness) was given. Mean percentage completeness was calculated for each format and compared using the two sample t-test.

RESULTS

Except for comments on the presence of 'histologically confirmed liver metastases' in CC and RC, 'distance from dentate line' and 'distance to circumferential margin' in RC, all other items were commented in more than 90% of reports, where 71% of the items based on the minimum data set were present in all reports. Compared to prose format, the mean percentage completeness (SD) improved from 74% (8) to 91% (4) (P < 0.0001) and from 81% (5) to 99% (1) (P < 0.0001) for RC and CC respectively in template proforma format.

CONCLUSION

A template proforma and surgeon's contribution in relation to operative findings improves the quality of the histopathology report in CRC.

Neoadjuvant therapy for rectal cancer down-stages the tumor but reduces lymph node harvest significantly

PURPOSE

The impact of neoadjuvant therapy (NAT) for rectal cancer on lymph node yield is not well known. This study evaluates the impact of NAT on tumor regression and lymph node harvest.

METHODS

The subjects were 40 patients with rectal cancer; 20 receiving high-dose, long-course neoadjuvant therapy, and 20 age- and sex-matched controls who did not receive neoadjuvant therapy. Tumor regression (TRG) was graded from 1 to 5 as: TRG1, no residual tumor cells; TRG2, occasional residual tumor cells with marked fibrosis; TRG3, marked fibrosis with scattered tumor cells or groups; TRG4, abundant cancer cells with little fibrosis; TRG5, no tumor regression. We also evaluated the number of lymph nodes retrieved from excised specimens, the size of the largest node, and the extent of lymph node involvement by the tumor.

RESULT

Tumor regression was seen in all patients; as TRG1 in 6 (30%), TRG2 in 2 (10%), TRG3 in 3 (15%), and TRG4 in 9 (45%). The median nodal harvest was 4 (range (0-12) in the NAT group vs 9 (range 1-19) in the control (P = 0.001). The median size of the largest lymph node was 5 mm (range 2-12 mm) in the NAT group vs 9 mm (range 4-15 mm) in the control group (P = 0.004). Tumor-positive nodes were identified in 4 of 17 of the NAT group patients and in 9 of the 20 controls (P = 0.308).

CONCLUSION

Although NAT down-stages rectal cancer, it results in a significantly low yield of lymph nodes, which are also significantly smaller than those in nonirradiated controls. Therefore, surgeons and histopathologists must ensure adequate sampling and accurate staging is done for patients with irradiated rectal cancer.

Comparison of one week and two weeks of triple therapy for the eradication of Helicobacter pylori in a Sri Lankan population: a randomised, controlled study

INTRODUCTION

Resistance of Helicobacter pylori to antibiotics may be particularly high in parts of the tropics. Infection may prove difficult to eradicate in such situations, and there is some evidence of benefit in increasing the duration of treatment (triple therapy) from 1 week to 2 or 3 weeks.

AIM

To assess the efficacy and tolerability of 1 week versus 2 weeks of triple therapy for eradication of H. pylori in a Sri Lankan population.

METHODS

Eighty two patients aged 18-70 years with gastritis or peptic ulcer and testing positive for H. pylori infection were randomly allocated to two treatment groups. Both groups received omeprazole 20 mg, clarithromycin 250 mg, and tinidazole 500 mg. Group A (n = 42) received the trial medication twice daily for 1 week and the Group B (n = 40) twice daily for 2 weeks. H. pylori eradication was defined as a negative 14C labelled urea breath test at 2 weeks after completion of the therapy.

RESULTS

H. pylori infection was eradicated in 36 (85.7%) patients in Group A and 36 (90%) patients in Group B (p = 0.9). Twenty three (55%) patients in Group A and 17 (43%) in Group B reported adverse effects attributable to trial medication (p = 0.387); none were serious. Three (7.5%) patients in Group B discontinued treatment due to adverse events that developed on days 7, 9 and 10.

CONCLUSION

Twice daily treatment with clarithromycin, tinidazole, and omeprazole for 1 week is well tolerated and provides as good a rate of H. pylori eradication as 2-week therapy in Sri Lankan patients.