Adenoma Detection is Increased in the Setting of Melanosis Coli

Colonoscopic Resolution of Melanosis Coli After Cessation of Senna Laxative Use

Melanosis coli occurs with the administration of stimulant laxatives for the relief of constipation. However, the duration of macroscopic improvement of melanosis coli after discontinuation of anthracene laxatives is not well understood. We describe the case of an 81-year-old female diagnosed with melanosis coli via colonoscopy who had been taking senna laxatives for 5 years. Seven months after cessation of senna laxatives, colonoscopy showed no melanosis coli in the colon. This impressive report describes the observation of melanosis coli with colonoscopy; 7 months after the withdrawal of senna stimulant laxatives, melanosis coli resolved.

Melanosis coli: a contrast effect or an oncogenic effect? A large-scale retrospective cohort study

BACKGROUND

Melanosis coli is characterized by brown mucosa with pigmentation. Studies have showed an increased adenoma detection rate in melanosis patients, whether it is caused by a contrast effect or an oncogenic effect is still controversial. The detection of serrated polys in melanosis patients remains unknown.

AIMS

The study aimed to clarify the correlation of adenoma detection rate with melanosis coli and discuss outcomes in less-experienced endoscopists. Serrated polyp detection rate was also been investigated.

METHODS

A total of 2150 patients and 39,630 controls were enrolled. A propensity score matching method was used to balance covariates between the two groups. The detection of polyps, adenomas, serrated polyps, and their features was analyzed.

RESULTS

The polyp detection rate (44.65% vs 41.01%, P = 0.005) and adenoma detection rate (30.34% vs 23.92%, P < 0.001) were significantly higher, and the serrated polyp detection rate (0.93% vs 1.58%, P = 0.033) was significantly lower in melanosis coli. The percentage of low-risk adenomas (44.60% vs 39.16%, P < 0.001) and polyps with 6 to 10 mm in size (20.16% vs 16.21%, P < 0.001) were higher in melanosis coli. The detection of large serrated polyps was lower (0.11% vs 0.41%, P = 0.026) in melanosis coli.

CONCLUSION

Melanosis coli correlates with an increased adenoma detection rate. The detection of large serrated polyps was lower in melanosis patients. Melanosis coli may not be considered a precancerous lesion.

Sustained ameliorating effects and autonomic mechanisms of transcutaneous electrical acustimulation at ST36 in patients with chronic constipation

BACKGROUND AND AIMS

The treatment of chronic constipation is still a great challenge in clinical practice. This study aimed to determine the efficacy and sustained effects of transcutaneous electrical acustimulation (TEA) at acupoint ST36 on the treatment of chronic constipation and explore possible underlying mechanisms.

METHODS

Forty-four patients with chronic constipation were recruited and randomly assigned to a TEA group or sham-TEA group. A bowel diary was recorded by the patients. The Patient Assessment of Constipation Symptom (PAC-SYM) and the Patient Assessment of Constipation Quality of Life (PAC-QoL) questionnaires were administered during each visit. Anal and rectal functions were evaluated with anorectal manometry. Autonomic functions were assessed by the special analysis of heart rate variability derived from the ECG recording.

RESULTS

Compared with sham-TEA, 2-week TEA treatment significantly increased the number of spontaneous bowel movements (SBMs) (5.64 ± 0.54 vs. 2.82 ± 0.36, P < 0.001) and lowered the total scores of PAC-SYM (0.90 ± 0.14 vs. 1.35 ± 0.13, P < 0.001) and PAC-QoL (0.89 ± 0.13 vs. 1.32 ± 0.14, P < 0.05). TEA improved symptoms, as reflected by a reduction in the straining (P < 0.001), the incomplete defecation (P < 0.05), the frequency of emergency drug use (P < 0.05), the days of abdominal distension (P < 0.01) and an increase in intestinal satisfaction (P < 0.01). Interestingly, the effects of TEA on the improvement of weekly SBMs sustained four weeks after the cessation of treatment (P < 0.001). Anorectal manometry indicated that 2-week treatment of TEA lowered the threshold of first sensation (P < 0.05), desire of defecation (P < 0.01) and maximum tolerable volume (P < 0.001) compared with sham-TEA group. TEA also significantly enhanced vagal activity, reflected by high-frequency band of heart rate variability, compared with sham-TEA (57.86 ± 1.83 vs. 48.51 ± 2.04, P < 0.01).

CONCLUSION

TEA ameliorates constipation with sustained effects, which may be mediated via improvement of rectal sensitivity and enhancement of vagal activity.

CLINICAL TRIAL REGISTRATION

[https://clinicaltrials.gov/], identifier [ChiCTR210004267].

Case report: Melanosis coli combined with colon cancer, causality or coincidence?

The habitual use of laxative containing anthraquinone glycosides is considered to be the main cause of melanosis coli (MC). In the past, most scholars considered MC to be a benign and reversible disease. However, new evidence has emerged that MC may increase the risk of colon cancer. Here, we report a case of a 48-year-old woman diagnosed with MC and colon cancer. Through a literature review of previous basic and clinical studies, we summarize existing evidence that reveals the possible association between MC and colon cancer. Although this case cannot establish causality between MC and colon cancer, a high level of clinical vigilance for occurrence of colon cancer in patients with MC should be maintained.

Melanosis coli: A factor not associated with histological progression of colorectal polyps

OBJECTIVE

In this study we aimed to investigate the association of melanosis coli (MC) and the colorectal polyp detection rate (PDR).

METHODS

In all, 1104 MC patients and 62 181 non-MC participants were enrolled. And 2208 controls were matched by participants' age and gender, and quality of bowel preparation using the propensity score matching (PSM) method. Additionally, 490 polyps in MC and 980 in controls matched by age and gender, and size and location of polyps were analyzed. The association of PDR and pathological features of polyps with MC were also analyzed.

RESULTS

MC patients showed a higher PDR (44.3% vs 39.3%, P = 0.006) and detection rate of low-grade adenoma (45.4% vs 36.7%, P = 0.002) but fewer large polyps (≥10 mm) (18.8% vs 26.9%, P = 0.001), fewer polyps in the left colon (33.5% vs 40.0%, P = 0.018), and a lower detection rate of advanced adenoma/adenocarcinoma (17.4% vs 24.3%, P = 0.003) than the matched controls. On multivariate logistic regression analysis, MC was independently associated with an increased PDR (odds ratio 1.184, 95% confidence interval 1.045-1.343, P = 0.008). Analysis targeting polyps showed that there were significant differences in age, gender, location, and pathology (P < 0.001) between polyps with and without MC. However, after adjusting for participants' age and gender, size and location of polyps, there was no difference between the two groups in pathology (P = 0.635).

CONCLUSION

MC is independently associated with increased colorectal PDR, but not with histological progression of polyps.

Colorectal neoplasms in melanosis coli: a survey in Japan and a worldwide meta-analysis

PURPOSE

The association between melanosis coli (MC) and colorectal neoplasms remains unclear. Thus, we primarily aimed to clarify the epidemiology of MC in the Japanese population, identify the relationship between the use of anthranoids and MC, and determine the prevalence of detected intestinal lesions in patients with MC. We subsequently conducted a meta-analysis of published data, including our results, to summarize the influence of MC on the prevalence of colonic neoplasms.

METHODS

We conducted a retrospective survey in Japan to investigate the effects of MC on intestinal disorders. The prevalence of colorectal neoplasms and ileal ulcers was evaluated by colonoscopy, and the clinical characteristics of the participants were investigated using an electronic database. Odds ratios for colorectal neoplasms were calculated. We also performed a meta-analysis using Review Manager to reveal the comprehensive relationship between MC and colorectal neoplasms.

RESULTS

We enrolled 690 Japanese participants in the primary study. The prevalence of regular anthranoid use was significantly higher in the MC group than in the control group (50.9% vs. 6.5%, p < 0.01). Hyperplastic/inflammatory polyps and adenomas were more frequently detected in the MC group than in the control group. In a meta-analysis of five studies, a significantly higher prevalence of hyperplastic/inflammatory polyps and adenomas was reported in the MC group than in the control group, while the incidence of adenocarcinoma was not significantly different between the two groups.

CONCLUSION

Although hyperplastic polyps and adenomas were more frequently detected in MC patients, MC was not associated with an elevated risk of colorectal cancer.

Melanosis coli: a case report

Background

Melanosis coli is a benign condition characterized by deposition of lipofuscin in colonic mucosa due to long-term laxative use.

Case presentation

Here I am reporting a case of an 85-year-old man who presented with constipation, with a history of long-term herbal medication intake as laxatives, and upon evaluation, he was found to have melanosis coli.

Conclusion

Melanosis coli is a common adverse effect of chronic laxative use which is more common in elderly population with constipation.

Comprehensive evaluation of the learning curve to achieve satisfactory adenoma detection rate

BACKGROUND AND AIM

The number of colonoscopies required to reach satisfactory adenoma detection rate (ADR) is not well established. The aim of this study was to identify the appropriate number of procedures required to attain satisfactory ADR for those well-trained endoscopists who have a cecal intubation rate (CIR) ≥ 90% and start to perform colonoscopy independently.

METHODS

All endoscopists with compelete independent colonoscopy data during career in our database were enrolled. The number of procedures required to achieve ADR ≥ 20% was identified by cumulative summation (Cusum), learning curve Cusum (LC-Cusum), and moving average method. Mixed effect logistic regression model was developed to determine the relationship between endoscopist as well as patient-related factors and adenoma detection.

RESULTS

A total of 24 943 procedures and 14 endoscopists were enrolled. By Cusum analysis, the interest point was at 207 procedures. By LC-Cusum analysis, 71% (10/14) and 86% (12/14) of endoscopists had attained satisfactory ADR after 200 and 300 procedures, respectively. By moving average method, endoscopists reached a mean ADR of 20% at 216 and 261 procedures over blocks of 50 and 100 procedures, respectively. The total number of procedures, number of daily procedures, patient age and gender, bowel preparation, sedation, and diverticulosis were significantly associated with adenoma detection.

CONCLUSIONS

This is the first study to investigate the learning curve of ADR for those well-trained endoscopists who have a CIR ≥ 90% and start to perform colonoscopy independently. Two hundred procedures might be an optimal number required to reach an ADR ≥ 20%.

Melanosis coli: A comprehensive review

Melanosis coli (MC) is a common condition characterized by a black or brown pigment deposited in the colorectal mucosa. It is a reversible condition that is influenced by many factors, such as living habits and bowel function. However, the epidemiology and etiology of MC are still unclear. Most studies show that there is a significant correlation between the use of anthraquinone laxatives and the occurrence of MC. At present, the mechanism of the apoptosis theory is widely recognized as regards the pathogenesis of MC. There is no specific clinical manifestation of MC, and its diagnosis is mainly based on a complimentary examination, such as endoscopic and histopathological tests. General treatment, such as changing living habits, is preferred, and medical or surgical treatment should not be considered in the absence of serious malignancy. The aim of this review is to systematically present and outline the concepts of the epidemiology, etiology, histopathology, pathogenesis, clinical manifestations, diagnosis and treatment of MC, in order to improve the understanding of this condition.

Retrospective study on melanosis coli as risk factor of colorectal neoplasm: a 3-year colonoscopic finding in Zhuhai Hospital, China

BACKGROUND

Melanosis coli (MC) is a colonoscopic finding in which the colonic mucosa appears darkly pigmented than usual and generally caused by extended anthranoid laxative use.

METHODS

We performed a retrospective study at Zhuhai Hospital to investigate the risk of MC for CR neoplasm development. A total of 12,776 patients who underwent colonoscopy from 2013 to 2016 including 250 diagnosed with MC and 500 controls were included in this study. Odds ratios (OR) and 95% confidence intervals (95%CI) for associations of MC with CR neoplasm detection were estimated using univariate and multivariable multinomial logistic analyses for known risk factors.

RESULTS

The presence of MC was associated with a significant increase in the CR neoplasm detection rate compared with controls (OR = 1.701, 95% CI = 1.252-2.31; P = 0.001). The effect was also observed in different tumor sites, age group, gender, and lifestyle. Using univariate multinomial analysis, patients with MC were significantly associated with both hyperplastic polyp (OR = 2.069, 95% CI = 1.253-3.415; P = 0.005) and low-grade (LG) adenoma (OR = 1.585, 95% CI = 1.115-2.254; P = 0.010). However, there was no significant difference with adenocarcinoma (OR = 1.701, 95% CI = 0.990-2.924; P = 0.055). Using multivariate multinomial analysis, MC patients remained associated with increased hyperplastic polyp (OR = 1.870, 95% CI = 1.119-3.125; P = 0.017) and LG adenoma (OR = 1.474, 95% CI = 1.027-2.114; P = 0.035), but not adenocarcinoma (OR = 1.620, 95% CI = 0.914-2.871; P = 0.098). A significant increase in CR neoplasm rate was observed with drinker, smoker, and elderly patients but not with gender.

CONCLUSION

Patients with MC were more likely to have both hyperplastic polyp and LG adenoma. If confirmed, such findings could suggest the discontinuation of anthranoid laxative use particularly in the elderly.

Quantitative Analysis of Melanosis Coli Colonic Mucosa Using Textural Patterns

Melanosis coli (MC) is a disease related to long-term use of anthranoid laxative agents. Patients with clinical constipation or obesity are more likely to use these drugs for long periods. Moreover, patients with MC are more likely to develop polyps, particularly adenomatous polyps. Adenomatous polyps can transform to colorectal cancer. Recognizing multiple polyps from MC is challenging due to their heterogeneity. Therefore, this study proposed a quantitative assessment of MC colonic mucosa with texture patterns. In total, the MC colonoscopy images of 1092 person-times were included in this study. At the beginning, the correlations among carcinoembryonic antigens, polyp texture, and pathology were analyzed. Then, 181 patients with MC were extracted for further analysis while patients having unclear images were excluded. By gray-level co-occurrence matrix, texture patterns in the colorectal images were extracted. Pearson correlation analysis indicated five texture features were significantly correlated with pathological results (p < 0.001). This result should be used in the future to design an instant help software to help the physician. The information of colonoscopy and image analystic data can provide clinicians with suggestions for assessing patients with MC.

Melanosis Coli: A Helpful Contrast Effect or a Harmful Pigmentation?

Background

Melanosis coli, a brown discoloration of colonic mucosa, is considered as a benign condition mainly observed in patients under chronic anthranoid laxatives. Recent data link this condition with an increased adenoma detection rate. Moreover, its tumorigenic potential and possible association with the development of colorectal cancer remains uncertain. We conducted this study to compare the polyp detection rate and colorectal cancer diagnosis in patients with melanosis against matched control group without melanosis.

Patients and methods

A retrospective single-center study. Patients diagnosed with melanosis coli on colonoscopy over a 15-year period were included. Each melanosis coli patient was matched with three controls by age, gender, setting (inpatient/outpatient), and procedure's indication. Polyp detection rate and diagnosis of colorectal cancer were recorded and compared between the groups before and after adjustment for bowel preparation.

Results

A cohort of 718 patients with melanosis and 2154 controls were included. The polyp detection rates were 33.4% and 21.8% of melanosis and control groups, respectively (P < .001). Melanosis coli, however, was associated with less diagnosis of colorectal cancer than controls (0.3% vs 3.9%; P < .001). In multivariate analysis, melanosis diagnosis on endoscopy was significantly associated with higher polyp detection rate (odds ratio [OR] = 1.986, 95% confidence interval [CI]: 1.626-2.425; P value < .01).

Conclusions

Melanosis coli is not associated with increased diagnosis of colorectal cancer. It is associated, however, with enhanced polyp detection likely due to chromo-endoscopy-like effect.

Gender, age, and concomitant diseases of melanosis coli in China: a multicenter study of 6,090 cases

BACKGROUNDS AND AIMS

Melanosis coli (MC) is a noninflammatory, benign, and reversible colonic disorder, but its detection rates in China are unclear. We therefore aimed to analyze the epidemiological characteristics of MC in China.

METHODS

We assessed the detection rates, associated factors and concomitant diseases of MC in the patients who underwent colonoscopy at eight medical centers across five regions of China between January 2006 and October 2016. All data were procured from the electronic database established at each participating institutions.

RESULTS

Among the 342,922 included cases, MC was detected in 6,090 cases (detection rate = 1.78%, 95% confidence interval, 1.73%-1.82%) at a mean age of 60 years. The detection rate gradually increased yearly, and along with the increasing age regardless of gender, while a rapid increase presented in the patients ≥60 years of age (0.58% for ≤25 years, 1.22% for 25-59 years, and 3.19% for ≥60 years). The detection rate was higher in females than in males; however, the rate of per-year increase was higher in males than in females at age of ≥60 years, which was 1.85-fold of that in females. Among cancer, polyp, inflammation, and diverticula, polyp was the most common concomitant disease of MC and identified in 41.72% of MC patients.

CONCLUSIONS

MC detection rates were increased annually and elevated in older patients, particularly in male patients. Males in the elderly population of ≥60 years were most likely to have MC. Colonic polyp is the most common concomitant disease of MC.

Melanosis coli: Harmless pigmentation? A case-control retrospective study of 657 cases

Backgrounds and aims

The association of melanosis coli with the development of colorectal polyps remains uncertain.

Methods

From a total of 18263 patients who had received colonoscopy in our hospital, 219 with melanosis coli cases and 438 controls matched by age and sex (at 1:2 ratio) were included in this study. The association of incidence, number, location, and pathology of colorectal neoplasm with grades and distribution of melanosis coli were analyzed.

Results

Melanosis coli was associated with significantly more colorectal polyps than control, a higher incidence of numerous colorectal polyps (number ≥ 20) (7.3% vs 0.5%; p < 0.001), and higher number of small colorectal polyps (diameter ≤ 5 mm; p < 0.01). Patients with melanosis coli had higher incidences of low-grade adenomas (31.1% vs 23.3%, p < 0.05) and non-adenoma polyps (20.1% vs 12.8%, p < 0.05) than the controls. On multivariate analysis, melanosis coli was independently associated with increased detecting rates of low grade adenoma (OR = 1.54; 95%: 1.06–2.23; p < .05), non-adenoma polyp (OR = 1.72; 95%: 1.11–2.70; p < .05) and numerous polyps (OR = 16.2, 95%: 3.66–71.6; p < .05). There was no significant difference in the incidence of high-grade adenomas or adenocarcinomas in the two population groups, but the numbers of these lesions were insufficient to permit firm conclusions. No significant differences in incidence, number, and pathology of colorectal polyps between individuals with melanosis coli of three different grades of severity were found. Melanosis located predominantly in the right colon had an interestingly lower incidence of colonic polyps in right colon than did melanosis located predominantly in the left colon or total colon (8.9% vs. 26.3%, 24.0%, p < 0.05). Patients with melanosis coli had significantly more nonspecific distal ileal ulcers than did controls (8.0% vs 0%, p < 0.001).

Conclusion

Melanosis coli is associated with a higher incidence and number of colonic non-adenoma polyps and low-grade adenomas, and higher incidence of distal ileal ulcers. Melanosis coli may not be a harmless pigmentation, but a sign of chronic injury of colonic and intestinal mucosa.