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A 68-year-old woman underwent positron emission tomography/CT (PET/CT) for staging of lung cancer. High ﬂuorodeoxyglucose signal (standardized uptake value maximum, 10.48) was identiﬁed in the ascending colon (A). Colonoscopy found a whitish, ﬂat elevated lesion with reddish depression (Paris class IIaþIIc) 15 mm in diameter in the ascending colon (B). Magniﬁcation colonoscopy demonstrated a type VI high-grade irregularity in the depressed area with a type II–like pit pattern in the ﬂat elevated area, according to Kudo’s classiﬁcation. According to these endoscopic ﬁndings, an early invasive cancer arising from a sessile serrated adenoma/polyp (SSA/P) was suspected. Laparoscopic-assisted right hemicoloectomy was performed, and the pathologic examination demonstrated moderately differentiated adenocarcinoma arising from a sessile serrated adenoma/polyp invading the muscular layer (C). This lesion was considered an adenocarcinoma developing through a serrated neoplastic pathway.
DISCLOSURE All authors disclosed no ﬁnancial relationships relevant to this publication. Ryo Seishima, MD, Department of Surgery, Keio University School of Medicine, Toshio Uraoka, MD, PhD, Department of Gastroenterology, National Hospital Organization Tokyo Medical Center, Hirotoshi Hasegawa, MD, PhD, Koji Okabayashi, MD, Masashi Tsuruta, MD, PhD, Department of Surgery, Yuichiro Hayashi, MD, PhD, Division of Diagnostic Pathology, Yuko Kitagawa, MD, PhD, Department of Surgery, Keio University School of Medicine, Tokyo, Japan
Commentary Serrated polyps are mysterious. The term “serrated polyp” encompasses 3 distinct classes of pathologic lesions: hyperplastic polyps, sessile serrated adenomas (SSA), and traditional serrated adenomas. In 1996, Emina Torlakovic coined the term “SSA” and began to question their premalignant potential as compared with their typically benign hyperplastic cousins. Small hyperplastic polyps in the distal colon likely have no malignant potential, but in nearly 4% of patients with large (>1 cm) SSAs, colon cancer develops over 10 years. Patients meeting the criteria for serrated polyposis syndrome likely have approximately a 7% chance of colon cancer over 5 years. Serrated polyps represent only 3 of every 10 polyps removed during screening colonoscopy, but larger and more proximal lesions are cause for concern. PET/CT scans have been studied in the evaluation of colorectal cancer (CRC), and their correlation with large polyps seen on colonoscopy. PET/CT is reasonably sensitive and speciﬁc for large polyps, but the cost is the obvious limiting factor for general screening. PET/CT is, however, quite valuable in the postdiagnosis management of CRC, when increasing levels of serum carcinoembryonic antigen may prompt consideration of PET/CT to assess for metastasis or distant recurrence. In this case, the PET/CT was diagnostic, but only because of an incidental ﬁnding. The mystery of large serrated polyps lies in their natural history. Given the predisposition of CRC in patients with SSAs, common sense would tell us that the SSAs themselves are the locus of tumor progression. However, a recent trial followed up 23 large sessile serrated adenomas left in situ for a median of 11 years; none of these polyps progressed to malignancy. This begs the question: when you see smoke, where is the ﬁre? Conventional adenomas are found in 1 of every 3 patients with an SSA. Could ﬁeld-effected adenomas be the actual premalignancy? Could some CRCs be not related to SSAs but simply aggressive adenomas in predisposed persons? Some data suggest that it is the adenomas that are burning, and SSAs are merely the fuel. William C. Palmer, MD Fellow in Gastroenterology & Hepatology, Mayo Clinic Florida Massimo Raimondo, MD Associate Editor for Focal Points
Pyogenic granuloma of the transverse colon A 40-year-old man visited our institution because of a 3-month history of rectal bleeding. He had 1 ﬁrst-degree relative who had died of colorectal cancer. The results of his physical examination were unremarkable. Laboratory
data included a hematocrit of 39% (normal, 42%-52%) a mean corpuscular volume of 82/fL (normal, 80-94/fL), and a white blood cell count of 10,500/mm3 (normal, 450010,000/mm3). Tumor markers, such as carcinoembryonic
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antigen, carbohydrate antigen 19-9, and a-fetal protein, were within normal limits. A colonoscopy showed a pedunculated reddish polyp in the transverse colon, measuring up to 25 mm, with a short wide stalk and an adherent whitish deposit on the head (A, B). The polyp was resected with a snare and electrocautery. Pathologic examination of the resected specimen revealed proliferating capillaries surrounded by inﬂammatory cells in a loose connective tissue stroma (C, H & E, orig. mag. 40). Immunohistochemical staining for CD34 showed positivity in endothelial cells lining well-deﬁned capillaries (D). A diagnosis of pyogenic granuloma was made. Three months later, the patient remained asymptomatic, and follow-up colonoscopy revealed no evidence of tumor recurrence.
DISCLOSURE All authors disclosed no ﬁnancial relationships relevant to this publication. Sheng-Lei Yan, MD, PhD, Shih-Feng Chen, MD, Division of Gastroenterology, Department of Internal Medicine, Chang Bing Show-Chwan Memorial Hospital, Chien-Hua Chen, MD, Yung-Hsiang Yeh, MD, Division of Gastroenterology, Department of Internal Medicine, Chang Bing Show-Chwan Memorial Hospital, and Division of Gastroenterology, Department of Internal Medicine, Show-Chwan Memorial Hospital, Changhua City, Taiwan http://dx.doi.org/10.1016/j.gie.2015.04.023
Commentary Pyogenic granuloma (PG), also known as granulation hemangioma, eruptive hemangioma, lobular capillary hemangioma, granuloma gravidarum, and tumor of pregnancy, is a vascular lesion ﬁrst described in 1897. It is found to involve gums, skin, nasal septum, and rarely the GI tract. The term pyogenic granuloma is misleading because it is not a true granuloma. It is a capillary hemangioma, which makes it prone to bleeding. It is also not truly pyogenic (pus producing) because the cause is postulated to be traumatic, not infectious. The size ranges from a few millimeters to centimeters. It can grow rapidly and will often bleed with little or no trauma. It can present at any age, and there is a female gender preference. PGs in the GI tract have been reported in the esophagus, stomach, small intestine, anal canal, and less commonly in the large intestine (so far only 15 cases of colorectal PG have been reported, including the present case). Its exact cause remains unknown. Colonic PGs have a left-sided predilection and a mean diameter of 1.6 cm (range, 0.5-3 cm). Endoscopically, PG can mimic colon cancer because of the irregular shape covered with thick exudate. Macroscopically, it is described as a red, polypoid, pedunculated, exophytic mass of apparent granulation tissue and surface ulceration or with a whitish coating that bleeds easily on contact. The differential diagnosis includes inﬂammatory polyp, bacillary 762 GASTROINTESTINAL ENDOSCOPY Volume 82, No. 4 : 2015
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angiomatosis, angiosarcoma, ﬂorid vascular proliferation related to intussusception/mucosal prolapse, reactive angioendotheliomatosis, and angiomatous variant of Kaposi sarcoma. The deﬁnitive diagnosis of PG is made with biopsy and histologic examination. The lesion needs to be removed by endoscopic mucosal resection for accurate diagnosis. Histology is characterized by proliferating capillaries surrounded by inﬂammatory cells in a loose connective tissue stroma. The most useful immunostains for tissue factors VIII, CD31, and CD34 highlight the endothelial cells lining capillary loops. Complete treatment of PG requires total excision, which, depending on size, is achieved by snare polypectomy, endoscopic mucosal resection, or surgical resection. In conclusion, colonic PG is an acquired polypoid hemangioma characterized by the distinctive vascular lobule. It can present with overt or occult, acute or chronic GI bleeding. Because of its unusual appearance, it can be misdiagnosed and treated as colon carcinoma with extensive surgery. Endoscopists and pathologists should be familiar with this condition to avoid overdiagnosis as a malignant vascular tumor. Bhaumik Brahmbhatt, MD Fellow in Gastroenterology & Hepatology, Mayo Clinic Florida Massimo Raimondo, MD Associate Editor for Focal Points
Fake out: a giant ﬁbroepithelial polyp mimicking a rectal tumor A 67-year-old man presented with abdominal pain and hematochezia and was referred for colonoscopy after a CT scan demonstrated a 3-cm rectal mass with adjacent lymphadenopathy, and numerous lesions in the liver,
pancreas, and bones (A). Colonoscopy demonstrated a 3.5-cm polypoid lesion arising near the anal verge (B). The patient then underwent rectal EUS (C). FNA of the rectal tumor had inadequate cellularity, and FNA specimens
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