Description:
A 68 year old African American female with a history of diabetes, hypertension, hyperlipidemia, diverticulosis, and arthritis presented with complaints of palpitations. She was tachycardic on admission with a pulse of 105. Further history revealed she had noted darkened stools 3 weeks prior to presentation. She also complained of occasional nausea and an episode of post-prandial vomiting. She took aspirin and motrin daily for her arthritis. A colonoscopy 5 years prior demonstrated diverticulosis and internal hemorrhoids.
Labs were unremarkable except for an iron deficiency anemia. After blood transfusion, a colonoscopy and upper endoscopy were performed. Colonoscopy redemonstrated diverticulosis and internal hemorrhoids. On initial upper endoscopy, there appeared to be a large duodenal mass. Note the appearance of the pylorus at the antrum.
Repeat upper endoscopy revealed a 4.5cm polyp prolapsed into the duodenum arising from the antrum along on a long, thick stalk. The lesion was imaged with a 20MHZ ultrasound probe revealing a homogenous hypoechoic lesion confined to the submucosa.
Given the patient’s history, endoscopic resection was planned. The polyp remained lodged in the duodenal bulb. An appreciation of its size can be seen in the video. To temporarily shrink the polyp and control post polypectomy bleeding, epinephrine was injected into the base of the stalk. The catheter was then used to pull back the polyp into the stomach. More epinephrine was injected on the other side of the stalk. An endoloop was used to strangulate the polyp stalk. It is important to leave adequate space between the endoloop and the snare. It is also important to provide adequate coagulation to minimize post polypectomy bleeding. A snare was used with standard ERBE settings to remove the polyp. The sample measured 4.5cm x 4cm x 3cm. There was some post procedure oozing which was controlled with coagulation and clip placement.
Histological examination revealed vascular congestion and ulceration in the surface mucosa. The lesion was well vascularized as seen by a large arteriole surrounded by smooth muscle. The lesion itself was a benign submucosal polyp comprised of loose fibroconnective tissue with various inflammatory cells. A lymphocytic infiltrate, eosinophils, and plasma cells can be seen. Staining was positive for CD34.
These findings are consistent with a Vanek polyp, coined by Dr. Vanek in 1949. Helwig and Ranier later coined the term inflammatory fibroid polyp in 1953. It is a rare lesion accounting for 1-3% of all gastric polyps. It is most common in the sixth decade of life with a slight male predominance. It can occur throughout the gi tract but the majority or approximately 70% occur in the gastric antrum. The next most common location is the ileum at 20% followed by the colon, jejunum, duodenum, and esophagus respectively.
An immunohistochemical profile was developed in 2004 to aid in the diagnosis.
The etiology of this lesion is unknown but has been thought to be an inflammatory response given the high number of lymphocytes and eosinophils. There has been some association with helicobacter pylori infection, but this does not account for noninfected patients or lesions that arise in the other parts of the gi tract. The lesion tends to be well vascularized. It has no known malignant potential.
Precautions and planning should be taken in preparation for removing these lesions as they tend to be quite vascular. Literature review has shown successful endoscopic removal.
Contributed By:
Gregory Lam, DO, SUNY Downstate Medical Center
Yvette Lam-Tsai, MD, SUNY Downstate Medical Center
