Gastro-duodenal artery embolization in a case of an advanced rectal neuroendocrine tumour

Clinical History

A 67-year-old man presented with malaena following investigation for bowel urgency, weight loss, and collapse. Colonoscopy revealed an ulcerated lesion in the lower rectum. Biopsies indicated a poorly differentiated rectal neuroendocrine carcinoma (grade 3, proliferative index Ki67 90%). He was then sent for outpatient oesophago-gastro duodenoscopy (OGD) and imaging.

Imaging Findings

Contrast-enhanced Chest/abdomen/pelvis CT demonstrated a primary lesion of 35 mm in length extending through the bowel wall (Fig. 1a). There was evidence of two enlarged lymph nodes, venous invasion and multiple liver metastases. The radiological stage of the malignancy was T4:N1:M1. Diverticula were noted to be arising from the second part of the duodenum. (Fig. 1b)

18-FDG PET CT demonstrates uptake in the rectum, pelvic lymph nodes, liver and diffusely within the skeletal system.

OGD shows a large mass with an adherent clot on the posterior wall of the duodenal bulb, which was morphologically assessed to be a duodenal metastasis. Although there was no active bleeding, it was not possible to definitively stop the bleeding endoscopically.

Subsequently definitive cessation of blood flow to the presumed metastasis was achieved through embolization of the gastro-duodenal artery (GDA) by inserting 3 coils (Fig. 2).

Discussion

A. Background

Rectal neuroendocrine carcinomas (RNEC) have an incidence of 0.86 per 100, 000. They account for 27% of all gastrointestinal neuroendocrine tumours of which only 5% have distant metastases, typically to the liver. [1] These tumours may be asymptomatic and can present as an incidental finding on endoscopy (approximately 40% of cases), or present with symptoms of changes in bowel habit, haematochezia, tenesmus and weight loss. [1, 2, 3, 4] Metastatic disease may present with symptoms of liver metastases and constitutional symptoms of carcinomatosis. [1]


B. Clinical Perspective

Prior to the onset of malaena, it had been decided that the patient would be treated using chemotherapy rather than undergoing tumour de-baulking surgery due to multiple comorbidities. Due to the inability of the OGD to control the duodenal bleed, embolisation of the gastro-duodenal artery was the least invasive method and therefore posed the least risk to the patient in comparison to surgery, which the patient may not have survived. Cessation of the bleed enabled the patient to recover to a stable state and return home.


C. Imaging Perspective

Transcatheter arterial embolisation (TAE) by interventional radiology is an established treatment for bleeding duodenal ulcers that are unable to be controlled by endoscopic intervention. [5] Although the vascular supply to the duodenum is rich with avid redundant supply, the procedure has been found to have a technical success rate of 98% and a clinical success rate of 87%. [5, 6]

D. Outcome

Owing to the urgent need for treatment, indicated by the progressive drop in blood pressure and haemoglobin along with the need for multiple blood transfusions, further treatment was indicated. Embolisation of the GDA by inserting 3 coils (4 mm x 14 cm) (Fig. 2) was carried out with interventional radiology to stop the blood flow to the bleeding lesion. Post-embolisation demonstrated no flow through the GDA. This resulted in patient recovery; in the three days post-procedure there were no further episodes of malaena, and Hb and blood pressure recovered.

E. Teaching Points

TAE may provide a palliative solution to stem the bleeding of ulcerated metastatic neuroendocrine tumours in the duodenum when the patient is not fit for surgical resection or if the bleeding is resistant to endoscopic intervention.

Differential Diagnosis List

Final Diagnosis

Duodenal metastasis of rectal neuroendocrine carcinoma

URL:	https://www.eurorad.org/case/12607
DOI:	10.1594/EURORAD/CASE.12607
ISSN:	1563-4086