Brown Bowel Syndrome Is a Rare and Commonly Missed Disease: A Case Report and Literature Review

Background. Brown bowel syndrome (BBS) is a rare gastrointestinal condition, and vitamin E deficiency has been considered to be a main contributor. However, vitamin E deficiency has been found in only a few patients throughout the published literature studies and its cutoff lab value for diagnosis is not entirely clarified. Case Presentation. A 56-year-old female patient with a history of congenital bowel obstruction (repaired at birth) presented with bloating, abdominal pain, and chronic diarrhea. Endoscopy identified unremarkable gastrointestinal mucosa except a few small polyps in the colon. A partial obstruction was detected by a small bowel follow-through series and then confirmed by CT scan. The resected small bowel was significantly dilated with a thickened brown wall and extensive serosal adhesion. Microscopic examination revealed unremarkable mucosa, but dense granular brown pigments were identified in the cytoplasm of the smooth muscle cells in the muscularis propria. These deposits resulted to be lipofuscin, and BBS was diagnosed. The patient was asymptomatic at 9-month follow-up after surgery without vitamin E supplement. Conclusion. Mitochondrial damage with lipofuscin deposition is at the root of BBS pathogenesis. Any etiology associated with mitochondrial damage can cause this disease, and vitamin E deficiency is just one of them. Dysmotility from extensive serosal adhesion could be a possible etiology for this patient. Due to overlapping symptoms, lipofuscin deposition primarily in the muscularis propria, and unclear serum value of vitamin E, this syndrome is often missed in routine clinical practice from the superficial biopsy. A transmural biopsy is necessary for a definite diagnosis.

Adjuvant chemotherapy impact on the overall survival of completely resected small bowel adenocarcinoma: An updated meta-analysis.

e16806 Background: While the small intestine represents around 75% of the length and more than 90% of the gastrointestinal tract mucosal surface, it contributes around 2% of gastrointestinal tumors. Adenocarcinoma which constitutes 40% of all small bowel tumors is the most common histology. Complete surgical resection of early-stage small bowel adenocarcinoma (SBAC) is the only proven potentially curative therapy. Due to the rarity of this disease and the absence of randomized trials, the benefit of postoperative adjuvant chemotherapy (ACT) in patients with completely resected localized SBAC has been controversial. A meta-analysis conducted in 2018 found no survival benefit for adjuvant therapies in SBAC. However, this meta-analysis combined studies that used adjuvant chemotherapy and chemoradiotherapy and included studies contaminated by other less chemosensitive histologies and more advanced and sometimes metastatic disease. The purpose of this meta-analysis is to evaluate the impact of ACT on the overall survival (OS) of patients with completely resected SBAC incorporating more recent studies. Methods: A review of the medical literature was conducted using online databases. Inclusion criteria consisted of resected small bowel adenocarcinoma, English language, publications from 2000 to the present, and comparative studies reporting OS with hazard ratios (HR) or Kaplan-Meier curves of patients that underwent ACT versus those that did not. Adjuvant chemoradiotherapy studies and those that reported aggregate OS for a cohort with mixed histologies were excluded. A meta-analysis was conducted using an inverse variance method with a random-effects model. Results: Nine retrospective series which included 2082 patients were selected and analyzed. The majority of SBAC patients that received ACT belonged to stages II & III. ACT was found to be significantly associated with better OS in patients with completely resected SBAC (HR 0.66, 95%CI: 0.56-0.78, p < 0.001). Conclusions: This is the first meta-analysis to show that adjuvant chemotherapy is associated with a survival benefit in patients with completely resected small bowel adenocarcinoma. In the absence of randomized clinical trials, this meta-analysis represents the most compelling data supporting the use of ACT in this patient population.

Longer small bowel segments are resected in emergency surgery for ileocaecal Crohn’s disease with a higher ileostomy and complication rate

Background Repeated intestinal resections may have disabling consequences in patients with Crohn’s disease even in the absence of short bowel syndrome. Our aim was to evaluate the length of resected small bowel in patients undergoing elective and emergency surgery for ileocolic Crohn’s disease. Methods A prospective observational study was conducted on patients undergoing surgery for ileocolonic Crohn’s disease in a single colorectal centre from May 2010 to April 2018. The following patients were included: (1) patients with first presentation of ileocaecal Crohn’s disease undergoing elective surgery; (2) patients with ileocaecal Crohn’s disease undergoing emergency surgery; (3) patients with recurrent Crohn’s disease of the distal ileum undergoing elective surgery. The primary outcomes were length of resected small bowel and the ileostomy rate. Operating time, complications and readmissions within 30 days were the secondary outcomes. Results One hundred and sixty-eight patients were included: 87 patients in the elective primary surgery group, 50 patients in the emergency surgery group and 31 in the elective redo surgery group. Eleven patients (22%) in the emergency surgery group had an ileostomy compared to 10 (11.5%) in the elective surgery group (p < 0.0001). In the emergency surgery group the median length of the resected small bowel was 10 cm longer than into the group having elective surgery for primary Crohn’s disease. Conclusions Patients undergoing emergency surgery for Crohn’s disease have a higher rate of stoma formation and 30-day complications. Laparoscopic surgery in the emergency setting has a higher conversion rate and involves resection of longer segments of small bowel.

Validation of lymphocyte to monocyte ratio in resected small bowel adenocarcinoma as a predictor of survival.

e15799 Background: Lymphocyte to monocyte ratio (LMR) has been described as a prognostic factor in many solid tumors including colorectal adenocarcinoma. LMR has not been investigated as a prognostic factor in small bowel cancers. In this study, we aimed to evaluate prognostic factors in resected small bowel adenocarcinoma including LMR. Methods: Two hundred forty-one patients who underwent resection for stage I-III small bowel adenocarcinoma were retrospectively identified utilizing the pathology database at a single tertiary referral institution from 1994 to 2015. All patients had complete follow up data and were included in the survival analysis. One hundred sixty-nine patients had preoperative peripheral blood counts available for analysis. Plot of martingale residuals against LMR were used to establish best cutoff points for LMR. A training set for LMR included consecutively identified patients from 2006 to 2015, and a validation cohort including patients identified from 1994 to 2005 was used. Overall survival was performed utilizing Kaplan-Meier method, and Wilcoxon tests were used for statistical comparisons. Cox proportional hazards were performed and all tests were two sided. P value of < 0.05 was considered significant. Results: Median overall survival for the entire group was 54.5 months (95% CI: 37.2-81.2 months) with 5- and 10-year overall survival of 48% and 35%. The training set for LMR included 81 patients, and the validation set included 88 patients. The cutoff of 1.56 was chosen based on most significant p value (p = 0.002). When combined, the overall area under the curve (AUC) for LMR was 0.63, p < 0.01, (specificity 37.3%, sensitivity 90.1%, positive predictive value 33.1%, and negative predictive value 92.2%). There were 126 patients with LMR > 1.56 and 43 patients with LMR < 1.56 in the entire cohort. In multivariate analysis, LMR under 1.56 was a negative prognostic factor, HR = 2.20 (95% CI: 1.27-3.84, p < 0.01). In addition to LMR, age > 60 years and advanced T stage were independently negative predictors of overall survival in all patients. Conclusions: Lymphocyte-to-monocyte ratio < 1.56 is a validated negative prognostic factor in resected small bowel adenocarcinoma.

Lymphocyte-to-monocyte ratio and neutrophil-to-lymphocyte ratio independently predict survival in resected small bowel adenocarcinoma.

426 Background: Small bowel adenocarcinoma is a rare malignancy affecting approximately 2,000 patients per year. There is a paucity of evidence prognosticating patients with small bowel adenocarcinoma. We aimed to evaluate multiple factors in patients with resected small bowel adenocarcinoma to determine any association with survival outcomes. Methods: Ninety three patients who underwent resection for stage I-III small bowel adenocarcinoma were retrospectively identified utilizing the pathology database at a single tertiary referral institution. All patients had complete follow up data and were included in the survival analysis. JMP software was used for statistical analysis. Overall survival was performed utilizing Kaplan-Meier method, and log-rank tests were used for statistical comparisons. Cox proportional hazards were performed to control for age, gender, location of tumor, tumor size, tumor stage, and adjuvant therapy. Sensitivity analysis was performed to establish best cutoff points for continuous variables. All tests were two sided and a P value of < 0.05 was considered significant. Results: The median age at diagnosis was 65 years (range 32-90). 61% were male. Median tumor size was 4.5 cm. There were 20, 36, and 37 patients with stage I, stage II, and stage III disease, respectively. Median overall survival (OS) was 151 months, 104 months, and 44 months for stages I, II, and III disease. In a multivariate analysis, independent predictor factors included presurgical lymphocyte to monocyte ratio (LMR) > 4.0, with a Hazard Ratio (HR) 0.13 (95% CI 0.007-0.69, p = 0.01), presurgical neutrophil to lymphocyte ratio (NLR) < 8.0, HR 0.39 (95% CI 0.17-0.96, p = 0.04), and tumor size < 7.5 cm, HR 0.22 (95% CI 0.07-0.85, p = 0.03). Stage, age, T stage, and N stage influenced overall survival in univariate analysis, but were not statistically significant on multivariate analysis. Conclusions: LMR and NLR independently predict survival in patients with resected small bowel adenocarcinoma.

Late metastatic colon cancer masquerading as primary jejunal carcinoma

Metastasis to the small bowel from a previously resected colorectal cancer is rare and may erroneously be diagnosed as a primary small bowel carcinoma. It usually occurs several years after the primary resection. We present the case of a 67-year-old man who had undergone left hemicolectomy for colon cancer 3 years earlier and returned with subacute small bowel obstruction. This was initially thought, based on preoperative radiological findings and normal colonoscopic examination, to be due a primary jejunal cancer. Even at surgery, the lesion convincingly appeared as an obstructing primary small bowel carcinoma. However, the histology of the resected small bowel revealed metastatic colon cancer. This rare and an unusual metastatic occurrence some years after the primary resection is described and reviewed.