Necrotizing Colitis with Perforation Proximal to Obstructive Ascending Colon Cancer: A Case Report

Abstract

Background

Necrotizing colitis (NC) with perforation is a rare complication of the obstructive cancer of the right colon.

Case description

We report here a case of a 45-year-old female patient of mucinous adenocarcinoma of ascending colon, which presented as acute NC with perforation proximal to obstructing colonic carcinoma with their imaging features on computed tomography (CT). The purpose of this article is to highlight the role of CT in distinguishing an ischemic and a tumoral segment in the carcinomas complicated by proximal bowel ischemia.

Conclusion

Imaging plays a great role in distinguishing an ischemic and a tumoral segment in carcinomas complicated by proximal bowel ischemia. The identification of NC will help to accurately stage colonic cancer.

How to cite this article

Satyam S, Jain K, Pradhan G. Necrotizing Colitis with Perforation Proximal to Obstructive Ascending Colon Cancer: A Case Report. Euroasian J Hepato-Gastroenterol 2022;12(2):95–97.

Introduction

Colorectal cancer (CRC) is the most common cancer of the gastrointestinal tract.¹ In the early stage, it progresses with subtle symptoms, and in only 15–30% of cases, it presents with complaints of the acute abdomen, such as perforation or obstructions. Complete obstruction occurs in patients in 8–40% of cases. Colorectal cancer is responsible for the majority of emergency colorectal surgeries, whereas the incidence of perforation is about 2.6–10%.² Colorectal cancer is rarely associated with necrotizing colitis and perforation. Acute necrotizing colitis is an ulcero–inflammatory lesion of the colon which complicates obstructive or partial obstructive CRC and occurs when obstructive colitis becomes severe. It is usually confused with extensive colorectal carcinoma. Very few cases have been reported of acute necrotizing colitis occurring due to colon cancer. Early diagnosis will prevent postsurgical complications.

We report here a case of mucinous adenocarcinoma of ascending colon, which presented as acute necrotizing colitis with perforation proximal to obstructing colonic carcinoma and their imaging features on CT and the importance of contrast-enhanced computed tomography (CECT) in diagnosis. The main aim of this article is to highlight the role of CT in distinguishing a tumoral and an ischemic segment in carcinomas complicated by proximal bowel ischemia.

Case Description

A 45-year-old female patient presented in the emergency department with chief complaints of diffuse abdominal pain and a lump over the right lower abdomen, which she noticed 1 week ago. The patient did not pass flatus or faces for the past 48 hours. She complained of a few episodes of bilious vomiting. There was no fever. She had a history of pulmonary tuberculosis 10–12 years ago.

On examination, there was a palpable lump on the right side of the abdomen measuring ~15 × 8 cm in size along with generalized abdominal distension and tenderness with absent bowel sounds. Blood tests showed raised white blood cells count with neutrophilia.

An urgent CECT of the abdomen was done, which revealed diffuse circumferential mural thickening of the cecum and ascending colon along with non-visualization of the appendix. There was extensive pericolic and mesenteric fat stranding. Multiple intra and retroperitoneal air foci were seen along the cecum and ascending colon. There was a collection in the right perinephric region at the lower pole of the kidney. Mild ascites and peritoneal thickening were noted (Figs 1 and 2). Based on CECT findings, the possibility of acute fulminant necrotizing colitis with suspicion of perforation was given.

Figs 1A and B.

Axial CECT scan of the abdomen shows (A) Irregular thickening of the cecum and ascending colon (red arrow) with extensive pericolic fat stranding (white arrow); and (B) Multiple air foci in the retroperitoneum on the right side (red arrow) with a small collection in the right perinephric region along the lower pole of the right kidney (white arrow)

Figs 2A and B.

Coronal reformatted images of CECT scan of the abdomen also shows (A) Irregular thickening of the cecum and ascending colon (red arrow); and (B) Multiple air foci

The patient underwent emergency laparotomy where diffuse wall thickening of the cecum and ascending colon was found with focal defect and spillage of fecal matter into the peritoneal cavity. Resection of a gangrenous segment of the bowel along with transverse colon mucus fistula with end ileostomy was performed (Fig. 3). The patient was then sent to the surgical intensive care unit, but unfortunately, the patient succumbed to death due to septic shock.

Figs 3A and B.

(A) Intraoperative image shows thickened ascending colon loop with multiple areas of perforation; (B) Macroscopic specimen of resected large bowel shows extensive gangrenous changes

The resected segment was sent for histopathological examination. The final pathology report showed mucinous adenocarcinoma of the ascending colon (Fig. 4).

Figs 4A to C.

Microscopic findings of resected specimen of colon adenocarcinoma (A) Hematoxylin; (B) Eosin; and (C) Mucicarmine stain

Discussion

Obstructive colitis with perforation in CRC is a challenging situation that often requires emergent care. Necrotizing colitis is a rare complication of obstructive colorectal carcinoma. It is the result of decreasing blood flow into the colonic wall, due to high endoluminal pressure secondary to proximal intestinal obstruction. It is seen in 0.3–7% of all CRC and affects people with over 50 years of age of both genders. Obstructive colitis typically affects the left side of the colon, especially the sigmoid colon. Rarely is the right side of the colon affected. It is very difficult to recognize during surgery. Only 2.6–10% of patients present with perforation as the initial presentation of the disease. Intestinal perforation may be seen on either the site of the tumor or on a more proximal site which can be caused by distention of the bowel due to peripheral obstruction.

Only a few cases of obstructive colitis with perforation in CRC have been reported involving the right-sided colon. The cecum is the most frequently involved site of proximal perforation in the case of CRC.

The term “necrotizing colitis” was apparently introduced³ in 1960 and Kremer⁴ was the first to report a case of NC. It has different names such as ulcero–inflammatory colitis,⁵ ischemic colitis,^6,7 ulcerative^5,8 or pseudo-ulcerative colitis,⁹ gangrenous colitis,¹⁰ obstructive colitis,^11,12 and idiopathic colitis.¹³

Abdominal pain, constipation or watery diarrhea, hematochezia, nausea, and vomiting are the common presenting symptoms among the patients. Patients usually do not have any past history of colitis.

Preoperatively, it is exceedingly challenging to identify any inflammatory bowel changes related to obstructive CRC. They are incidentally detected by operating surgeons during surgery, or by pathologists during the examination of the gross specimen. The colonoscopy and barium or hydrosoluble enema can detect the primary tumor but usually fail to diagnose necrotizing enterocolitis and the extent of the necrosis.⁹ Computed tomography is the most common imaging modality that can help in the detection and diagnosis of colorectal carcinoma with necrotizing enterocolitis and perforation. It is a sensitive modality for detecting causes of obstruction, site of obstruction, and perforation. When there is high-grade colonic obstruction, it is useful for identifying a proximal ischemic segment. It distinguishes an ischemic from a tumoral segment in patients with necrotizing colitis proximal to colonic carcinoma. The identification of this entity will help to accurately stage colonic cancer. Moreover, it may help and guide surgeons during surgery so that they should exclude necrotic segments before anastomosis and not leave any associated lesions. Moreover, CT is widely available.

Usually, ischemic colitis proximal to obstructing carcinoma can be mistaken for extensive colonic carcinoma. Colonic cancer with a concomitant ischemic segment when present together may give the appearance of a longer tumoral segment than is actually the case even on CT abdomen. Proper identification of this pathologic process prior to surgery will assist surgeons in avoiding potential postoperative complications. Therefore, during surgery of obstructive CRC patients, obstructive colitis should always be considered. The association of ischemic damage proximal to an obstructive CRC should draw the radiologist's attention.

Conclusion

Colorectal cancer is rarely associated with necrotizing enterocolitis. In this, lesions are limited to mucosa or submucosa and serosa is spared which makes it difficult to diagnosis. It causes diagnostic and therapeutic difficulties. In carcinomas complicated by proximal bowel ischemia, imaging is crucial in distinguishing an ischemic from a tumoral segment.