Case Study: Painful Distended Abdomen and Weight Loss — What Is the Cause?

A 57-year-old woman with long-term liver cirrhosis and ulcerative colitis presented to the emergency department with severe abdominal distension and pain. Twenty years ago she had declined to have her colonoscopy for suspected inflammatory bowel disease (IBD). A CT scan now reveals that untreated IBD is the least of her problems. Al-Buti, M.D., and colleagues American Journal of Case Reports.

The woman described alternating constipation and loose stools for the past two weeks, along with stomach pain. Upon further questioning, her clinician learned that she had no appetite and that she had lost weight over the past two years. When she asked about her medical history, she described her one isolated incident of severe abdominal pain with diarrhea and rectal bleeding 20 years earlier. Because of suspicion of IBD, the clinician recommended a colonoscopy, but the patient refused and was neither diagnosed nor treated.

Physical examination, clinical examination, CT findings

The patient’s vital signs were normal, but she appeared malnourished and dehydrated. Her distended abdomen was mildly tender to palpation and “dull” to percussion.

Laboratory findings on admission were in the normal range, except for slightly lower levels of hemoglobin (9.7 g/dL vs. normal range of 12.1–15.1 g/dL) and sodium (117 mEq/L vs. 135–145 mEq/L). was inside. Tumor marker showing elevated levels of CA-125 (233 U/mL vs. normal levels <35 U/mL).

Abdominal and pelvic CT confirmed significant colonic distension. The cecum diameter was 8.5 cm, which was reduced to a short stricture of 2 cm in the central transverse colon and another stricture of 5 cm in the distal descending colon. The scan also showed a polypoid mass located in the medial colon wall some distance from the descending colon.

Al Buthi and co-authors noted that some findings are suggestive of IBD, specifically ulcerative colitis (UC). This includes evidence of inflammation characterized by irregular mucosal thickening, hyperplasia, and fat stranding adjacent to the colon, and lead pipe signs.

Cirrhosis, HCV

Scans also showed that the patient’s liver was cirrhotic, with multiple low-density micronodules and evidence of thrombosis affecting the right hepatic vein.

The clinician was concerned about the findings of cirrhosis and ordered additional laboratory tests showing the presence of hepatitis C virus (HCV), classified as Child-Pugh score B with ascites and hepatic vein thrombosis.

Therefore, based on findings of comorbid cirrhosis and intestinal obstruction, the patient’s condition was determined to be unstable and was admitted to the intensive care unit (ICU).

surgery, pathology

Clinicians planned an operation to bypass the stoma, temporarily remove the blockage, and allow biopsy of the lesion to provide the patient with a complete diagnosis and stage of the cancer. They hoped to clinically strengthen the patient in preparation for “appropriate planning of the final resection and extent of resection.”

A pathology report of a biopsy specimen from the transverse colon pointed to large cells reflecting the morphology of adenocarcinoma and neuroendocrine carcinoma. Immunohistochemical staining revealed that more than half of the tumors were positive for synaptophysin and CDX2, with a Ki67 index of 75%. Furthermore, CK20 positivity was observed in more than 40% of cancer cells.

Diagnosis: mixed neuroendocrine and non-neuroendocrine tumors

Therefore, the biopsy findings reflected a poorly differentiated neuroendocrine-nonneuroendocrine tumor (MiNEN) in the background of active chronic colitis, confirming the diagnosis of UC.

In addition, an MRI of liver lesions taken to rule out metastases confirmed re-demonstration of cirrhosis with no evidence of worrisome lesions.

The patient was started on hydrocortisone and supportive care during hospitalization, but there was no evidence of significant improvement. The decision was made to proceed with high-risk surgery for total colectomy in view of the malignancy of the patient.

A colonic examination revealed one stricture in the transverse colon and two other masses in the descending colon. The team then performed a total colectomy and ileostomy and sent the specimen for pathological examination.

This report identified a multifocal colonic tumor with three distinct masses. A mass located in the transverse colon at the site of stricture showed poorly differentiated neuroendocrine carcinoma, Ki67 >70%, and MiNEN, a poorly differentiated signet cell carcinoma located within 1 mm of the serosal surface.

Of the two remaining masses in the descending colon, one was a poorly differentiated marked cell carcinoma and the other was a moderately differentiated adenocarcinoma. The final pathological stage was mpT3 N2b M0.

Postoperative course and follow-up

After surgery, the patient’s general condition improved, and he was discharged from the ICU and advised to return for cirrhosis monitoring. Her clinician agreed that her comorbidities and her general condition put her at high risk for adjuvant chemotherapy.

Two weeks after discharge, she returned to the clinic, where a physical examination showed that the surgical incision had healed completely. After she was briefed about her advanced disease status, her patient and family decided to continue in palliative care only.

After 6 months, the patient returned to the emergency department due to extreme fatigue and poor oral intake. Her evaluation showed that she suffered from severe electrolyte disturbances with severe hyponatremia and severe hyperkalemia (sodium level 118 mEq/L, potassium level 7.1 mEq/L) . She was hospitalized and received medical and supportive management, but she eventually died of respiratory failure.

discussion

Discussing this case of MiNEN, a combination of both adenocarcinoma and neuroendocrine carcinoma, Al Buthi and co-authors found this rare case of neuroendocrine tumor involving the colon in the context of an underlying chronic inflammatory disease. The aggressive subtype was said to account for only 1.16 cases per visit. 1 million people.

In terms of the big picture, the case authors stated that UC patients have a higher risk of developing colorectal cancer (CRC) than the general population, with an overall risk of 1.29 per 1,000 IBD patients.

Among all CRCs, NEN is very rare in the colon, accounting for less than 1% of CRCs and even fewer in IBD patients, the authors write, and the literature reports only It points out that there are only 16 cases. Similarly, her NEN associated with UC affects twice as many men as she does women. This case is his one of only four reports of coexistence of IBD and MiNEN, making the current case even more rare.

NEN is known to have a poor prognosis, partly because more than half of reported cases frequently metastasize to the liver, the authors explained, with one He added that the annual survival rate was 40%.

feature

MiNEN is defined as the presence of adenocarcinoma components in more than 30% of the tumor mass and is characterized by strong synaptophysin staining and a positive Ki67 marker in more than 70% of cases, including this one, Al Buthi and co-authors said. rice field.

Of the three other MINEN cases reported, two involved the rectum and one involved the sigmoid colon, but this particular patient’s case involved the descending colon along with two other masses. A colonic MiNEN was found.

The authors point out that at least 30% of tumors with MINEN are identifiable as discrete components recognizable morphologically and immunohistochemically. “Most epithelial tumors of the gastrointestinal tract are subdivided into either pure glandular or squamous tumors (or their precursors) or pure neuroendocrine tumors.”

Histopathological analysis of glandular and squamous neoplasms may identify some scattered neuroendocrine cells, “but this finding does not affect classification,” the group said, and indeed, Note that in rare cases, epithelial neoplasms may contain significant populations of neuroendocrine and non-cells. – Neuroendocrine cells.

Previously, mixed neoplasms, in which each component accounted for 30% or more of the neoplasm, were classified as mixed glandular neuroendocrine carcinomas. The new term mixed neuroendocrine/non-neuroendocrine tumor is being used to reflect the possibility that the neuroendocrine component may not be an adenocarcinoma and one or both components may not be cancer, says Al Burhi explained the co-author.

According to the 2019 WHO Classification of Tumors of the Gastrointestinal System, “MiNEN is considered a conceptual category of neoplasm rather than a specific diagnosis”. This is because different types of her MiNEN can occur in different locations throughout the gastrointestinal pancreatic system.

Administrative recommendations

Al Buthi and co-authors, although little is known about the prognosis and the approach to treatment has not yet been defined, showed that surgical resectable moderate MiNEN and both tumors when distant metastases were detected. He said he is recommending chemotherapy that targets the ingredients.

“High-grade MiNEN is considered the most commonly seen and most aggressive type in our patient,” the group wrote. Includes surgery and adjuvant chemotherapy for localized disease and systemic chemotherapy for distant metastases. The team also cited the latest guidelines from the National Comprehensive Cancer Network. The guidelines state that his MiNENs of the gastrointestinal tract are associated with a poor prognosis and should be managed according to guidelines for adenocarcinoma of the colon and rectum.

“After encountering this case and reviewing the literature, we identified a clear association and found specific features between MiNEN and UC,” the case authors concluded. “Considered to be rare, this represents a distinct disease feature that requires further evaluation.Further research studies using larger sample sizes will help to understand etiology, diagnosis, management and prognosis. It helps you to.”