Digestive Endoscopy 2013; 25: 626–629
doi: 10.1111/j.1443-1661.2012.01405.x
Case Report
Extended hemangioma from pharynx to esophagus that could be misdiagnosed as an esophageal varix on endoscopy Jong Won Won,1 Hyun Woong Lee,1 Kyu Hyun Yoon,1 Suh Yoon Yang,1 In Seok Moon2 and Tae Jin Lee3 Departments of 1Internal Medicine, 2Otorhinolaryngology and 3Pathology, Chung-Ang University College of Medicine, Seoul, Korea
Giant hemangioma in the neck and head is an uncommon vascular neoplasm and has an unpredictable clinical behavior. We report a hemangioma that extended from the pharynx to the esophagus that could have been misdiagnosed as an esophageal varix. A 42-year-old man with dilated varices-like vessels on his esophagus that were incidentally detected by endoscopy was referred to our hospital for further evaluation. On re-examined endoscopy, multiple vascular dilatations were noted in the pharynx, expanding into the esophagogastric junction. These dilatations looked like esophageal varices that are found in patients with liver cirrhosis. There was no significant abnormality, including liver cirrhosis, on the abdomino-pelvic computed tomography scan. On the endoscopic esophageal biopsy, dilated
Key words: esophagus, hemangioma, pharynx, varices, varix.
INTRODUCTION
CASE REPORT
G
A
IANT HEMANGIOMA OF the neck and head is an uncommon vascular neoplasm with unpredictable clinical behavior. Especially among benign tumors of the esophagus, esophageal hemangioma is relatively rare.1 Hemangiomas are not very progressive tumors and, in most cases, clinical observation is the best therapy. For accurate treatment of any malady, exact diagnosis is needed, and we must be able to differentially diagnose similar syndromes and vascular abnormalities, such as the distinction between a varix and a hemangioma. We report a hemangioma that extended from the pharynx to the esophagus that could have been misdiagnosed as an esophageal varix.
Corresponding: Hyun Woong Lee, Department of Internal Medicine, Chung-Ang University College of Medicine, 224-1 Heuk SeokDong, Dongjak-Ku, Seoul 156-755, Republic of Korea. Email: [email protected] Received 18 May 2012; accepted 21 September 2012.
626 bs_bs_banner
submucosal blood vessels were diagnosed as hemangioma. In consultation with an otorhinolaryngologist for evaluation of the risk of hemangioma, it was determined that the hemangioma was not dangerous to the patient as long as it did not cause hoarseness, dyspnea or dysphagia. We planned regular 6-month follow ups. We report a case of extended hemangioma that could possibly have been misdiagnosed as an esophageal varix on endoscopy. Even if head and neck hemangioma is uncommon, careful consideration during endoscopy is required to avoid the misdiagnosis of varices or hemangioma.
42-YEAR-OLD MAN was incidentally found during endoscopy to have dilated varices-like vessels on his esophagus. He was referred to our hospital for further evaluation of this lesion. Other than these vessels, he was healthy and did not have any other symptoms. On reexamined endoscopy, multiple vascular dilatations were noted in the pharynx, expanding into the esophagogastric junction (EGJ) (Fig. 1). These vascular dilatations looked like esophageal varices that are often found in patients with liver cirrhosis. We analyzed the abdomino-pelvic computed tomography (CT) scan of the present patient for evaluation of liver cirrhosis. On CT scan, the esophageal wall underwent edematous changes that had an appearance similar to esophageal varices. However, no significant abnormality, including liver cirrhosis, was observed (Fig. 2). To achieve an accurate diagnosis, an endoscopic biopsy of the esophagus was carried out, although there was a risk of bleeding and consequential complications. Single endoscopic biopsy was done carefully at a nodular erythematous
© 2012 The Authors Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society
Digestive Endoscopy 2013; 25: 626–629
A
B
C
D
Hemangioma from pharynx to esophagus 627
Figure 1 Endoscopic findings of the pharynx and esophagus. (a) Pharynx: Multiple vascular ectasias are shown on the perivocal cord. (b) Esophagus: Multiple vascular dilatations are noted on the upper esophagus extending to the esophagogastric junction. Single endoscopic biopsy was done carefully at a nodular erythematous lesion at the mid-esophagus, 28 cm from the upper incisor using standard-type fenestrated forceps. A 1-mm diameter cup volume of this forceps minimized tissue damage and bleeding. (c) After taking a biopsy, active bleeding occurred at the biopsy site. (d) Bleeding was controlled by clipping using a standard cartridge-housed clip.
Figure 2 Abdomino-pelvic computed tomography scan findings of the liver and esophagus. Submucosal layer of the distal esophagus was edematous and thickened (arrow).
Figure 3 Pathological findings of the esophageal lesion. Thinand thick-walled blood vessels with dilated lumens are observed in the submucosa of the esophagus (HE, ¥40).
lesion at the mid-esophagus, 28 cm from the upper incisor using standard-type fenestrated forceps (Fig. 1B). A 1-mm diameter cup volume of this forceps minimized tissue damage and bleeding. After taking a biopsy, active bleeding occurred at the biopsy site (Fig. 1c). Bleeding was controlled by clipping using a standard cartridge-housed clip (Fig. 1d). Histological findings showed thin- and thickwalled blood vessels with dilated lumens in the submucosa of the esophagus (Fig. 3). The pathological diagnosis was consistent with hemangioma. To rule out syndromes that have abnormal vascular gastrointestinal (GI) tract features (e.g. Osler-Weber-Rendu syndrome, blue rubber bleb nevus syndrome), we carried out chest dynamic CT, brain magnetic resonance image (MRI) and thyroid ultrasonography. No vascular abnormality was detected. The abnormal vasculature was attributed to a simple giant hemangioma that extended from the pharynx to the esophagus. After consultation with an otorhinolaryngologist for evaluation of the risk of hemangioma, no danger was expected as long as the hemangioma did not cause hoarseness, dyspnea or dysphagia. The patient was prescribed regular 6-month follow ups. He has been followed for two and a half years, and there have been no symptoms, nor signs of progression.
DISCUSSION
I
N THE HEAD and neck, hemangiomas usually arise on the parotid gland, tongue and larynx. However, in the present case, the giant hemangioma occupied the pharynx
© 2012 The Authors Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society
628
J. W. Won et al.
and esophagus.2 Esophageal hemangioma is a rare benign vascular tumor. Review of 106 cases of vascular GI tumors from the Mayo Clinic revealed only two hemangiomas involving the esophagus.3 Moersch et al. reported esophageal hemangioma in only three (0.04%) of 7459 autopsy cases.1 Most hemangiomas of the head and neck are congenital, 70% of hemangiomas are present at birth and 85% are noted within the first year after birth.4 Like other head and neck hemangiomas, silent esophageal hemangioma needs no special treatment other than close observation. However, if such a malady was found to not be a simple hemangioma but a varix or other systemic vascular disease, it should be immediately evaluated and treated for a better prognosis. In our case, the hemangioma was incidentally detected during a health check-up of a 42-year-old man, and the features suggested an esophageal varix. Because esophageal hemangioma has the same shape and appearance of varices, it is very difficult to discriminate extensive esophageal hemangioma from varices with an endoscope. However, it is extremely rare in cirrhotic patients that varices are observed in the oropharynx. This is the only differential point. In the present case, endoscopic biopsy fortunately succeeded and no major complications were found. However, it should be noted that there is a known high risk of bleeding and consequential complications following an endoscopic biopsy. Thus, for a differential diagnosis, the presence of liver cirrhosis and endoscopic findings, such as the location of the lesion, should be considered first and foremost rather than the histological evaluation. In a simple hemangioma, variceal ligation will increase the bleeding risk,5 and non-selective beta blockers are recommended. We also analyzed this patient’s CT scan for liver cirrhosis. There are several syndromes that involve GI tract vascular abnormality, including blue rubber bleb nevus syndrome and Osler-Weber-Rendu disease. According to the diagnosis, treatment and prognosis will be different. Therefore, we must distinguish hemangioma from varices or vascular abnormality syndromes. Luminal hemangiomas of the GI tract have been reported as part of blue rubber bleb nevus syndrome.6 This syndrome typically involves the skin and GI system but can involve the central nervous system (CNS), thyroid and other areas. If the disease involves the CNS, it can be fatal.7 Therefore, accurate diagnosis is needed. Patients with personal or family history of Osler-WeberRendu disease may present with multiple esophageal hemangiomas (our patient denied such history).8 OslerWeber-Rendu disease is characterized by arteriovenous malformation (AVM), and the main areas of involvement are the
Digestive Endoscopy 2013; 25: 626–629
nasal mucosa, GI tract, pulmonary vasculature, and brain. The life expectancy of patients with Osler-Weber-Rendu disease and pulmonary AVM or cerebral AVM appears to be significantly lower. Therefore, we carried out brain MRI, thyroid ultrasonography, and dynamic chest CT in the present patient. No other vascular abnormality was found, so the diagnosis was simple esophageal hemangioma. In patients with additional symptoms such as hemangioma bleeding, aero-digestive tract stenosis and cosmetic problems, hemangiomas may require treatment. For treatment of esophageal hemangioma, esophagectomy or tumor enucleation has been carried out. Recently, endoscopic sclerotherapy, laser therapy, and endoscopic mucosal resection have also been reported.9 In addition, in recent studies, the efficacy and response rate of steroid treatment were about 80% in reducing the size and relieving symptoms. However, in patients older than 6 months the response diminishes with age. The efficacy of radiation therapy has also been demonstrated in various reports. Because of the organ-specific late radiation adverse effects and the possibility of secondary malignancy, radiation therapy is usually carried out only after other therapies have failed.10 In the present case, the hemangioma was too extensive for esophagectomy or endoscopic mucosal resection because the bleeding risk was very high. The patient was not demonstrating any other symptoms, including hoarseness, dyspnea, or indigestion; therefore, we decided to observe and follow up regularly. We report a case of extended hemangioma that could have been misdiagnosed as an esophageal varix. Because head and neck hemangioma is uncommon, suspected cases must be differentiated from many other possible diseases, and careful consideration during endoscopy must be undertaken to assure proper distinction between a varix and a hemangioma.
CONFLICT OF INTERESTS
A
UTHORS DECLARE NO conflict of interests for this article.
REFERENCES 1 Sogabe M, Taniki T, Fukui Y et al. A patient with esophageal hemangioma treated by endoscopic mucosal resection: A case report and review of the literature. J. Med. Invest. 2006; 53: 177–82. 2 Kano M, Kameyama K, Hosoda Y, Sugino K, Ito K. A cavernous haemangioma of the thyroid gland. J. Laryngol. Otol. 2005; 119: 828–30. 3 Gentry RW, Dockerty MB, Glagett OT. Vascular malformations and vascular tumors of the gastrointestinal tract. Surg. Gynecol. Obstet. 1949; 88: 281–323.
© 2012 The Authors Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society
Digestive Endoscopy 2013; 25: 626–629
Hemangioma from pharynx to esophagus 629
4 Shpitzer T, Noyek AM, Witterick I et al. Noncutaneous cavernous hemangiomas of the head and neck. Am. J. Otolaryngol. 1997; 18: 367–74. 5 Lebrec D, Poynard T, Hillon P, Benhamou JP. Propranolol for prevention of recurrent gastrointestinal bleeding in patients with cirrhosis:A controlled study. N. Engl. J. Med. 1981; 305: 1371–4. 6 Lopes L, Ramada J, Certo M. Blue rubber bleb nevus syndrome: Capsule endoscopy in a patient with GI bleeding. Gastrointest. Endosc. 2007; 65: 151–2. 7 Park CO, Park J, Chung KY. Blue rubber bleb nevus syndrome with central nervous system involvement. J. Dermatol. 2006; 33: 649–51.
8 Loughry RW. Hemangiomas of the esophagus. Rocky Mt Med. J. 1971; 68: 37–9. 9 Shigemitsu K, Naomoto Y, Yamatsuji T et al. Esophageal hemangioma successfully treated by fulguration using potassium titanyl phosphate/yttrium aluminum garnet (KTP/YAG) laser: A case report. Dis. Esophagus 2000; 13: 161–4. 10 Huang CM, Lee KW, Huang CJ. Radiation therapy for lifethreatening huge laryngeal hemangioma involving pharynx and parapharyngeal space. Head Neck 2013; 35: e98–101.
© 2012 The Authors Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society
doi: 10.1111/j.1443-1661.2012.01405.x
Case Report
Extended hemangioma from pharynx to esophagus that could be misdiagnosed as an esophageal varix on endoscopy Jong Won Won,1 Hyun Woong Lee,1 Kyu Hyun Yoon,1 Suh Yoon Yang,1 In Seok Moon2 and Tae Jin Lee3 Departments of 1Internal Medicine, 2Otorhinolaryngology and 3Pathology, Chung-Ang University College of Medicine, Seoul, Korea
Giant hemangioma in the neck and head is an uncommon vascular neoplasm and has an unpredictable clinical behavior. We report a hemangioma that extended from the pharynx to the esophagus that could have been misdiagnosed as an esophageal varix. A 42-year-old man with dilated varices-like vessels on his esophagus that were incidentally detected by endoscopy was referred to our hospital for further evaluation. On re-examined endoscopy, multiple vascular dilatations were noted in the pharynx, expanding into the esophagogastric junction. These dilatations looked like esophageal varices that are found in patients with liver cirrhosis. There was no significant abnormality, including liver cirrhosis, on the abdomino-pelvic computed tomography scan. On the endoscopic esophageal biopsy, dilated
Key words: esophagus, hemangioma, pharynx, varices, varix.
INTRODUCTION
CASE REPORT
G
A
IANT HEMANGIOMA OF the neck and head is an uncommon vascular neoplasm with unpredictable clinical behavior. Especially among benign tumors of the esophagus, esophageal hemangioma is relatively rare.1 Hemangiomas are not very progressive tumors and, in most cases, clinical observation is the best therapy. For accurate treatment of any malady, exact diagnosis is needed, and we must be able to differentially diagnose similar syndromes and vascular abnormalities, such as the distinction between a varix and a hemangioma. We report a hemangioma that extended from the pharynx to the esophagus that could have been misdiagnosed as an esophageal varix.
Corresponding: Hyun Woong Lee, Department of Internal Medicine, Chung-Ang University College of Medicine, 224-1 Heuk SeokDong, Dongjak-Ku, Seoul 156-755, Republic of Korea. Email: [email protected] Received 18 May 2012; accepted 21 September 2012.
626 bs_bs_banner
submucosal blood vessels were diagnosed as hemangioma. In consultation with an otorhinolaryngologist for evaluation of the risk of hemangioma, it was determined that the hemangioma was not dangerous to the patient as long as it did not cause hoarseness, dyspnea or dysphagia. We planned regular 6-month follow ups. We report a case of extended hemangioma that could possibly have been misdiagnosed as an esophageal varix on endoscopy. Even if head and neck hemangioma is uncommon, careful consideration during endoscopy is required to avoid the misdiagnosis of varices or hemangioma.
42-YEAR-OLD MAN was incidentally found during endoscopy to have dilated varices-like vessels on his esophagus. He was referred to our hospital for further evaluation of this lesion. Other than these vessels, he was healthy and did not have any other symptoms. On reexamined endoscopy, multiple vascular dilatations were noted in the pharynx, expanding into the esophagogastric junction (EGJ) (Fig. 1). These vascular dilatations looked like esophageal varices that are often found in patients with liver cirrhosis. We analyzed the abdomino-pelvic computed tomography (CT) scan of the present patient for evaluation of liver cirrhosis. On CT scan, the esophageal wall underwent edematous changes that had an appearance similar to esophageal varices. However, no significant abnormality, including liver cirrhosis, was observed (Fig. 2). To achieve an accurate diagnosis, an endoscopic biopsy of the esophagus was carried out, although there was a risk of bleeding and consequential complications. Single endoscopic biopsy was done carefully at a nodular erythematous
© 2012 The Authors Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society
Digestive Endoscopy 2013; 25: 626–629
A
B
C
D
Hemangioma from pharynx to esophagus 627
Figure 1 Endoscopic findings of the pharynx and esophagus. (a) Pharynx: Multiple vascular ectasias are shown on the perivocal cord. (b) Esophagus: Multiple vascular dilatations are noted on the upper esophagus extending to the esophagogastric junction. Single endoscopic biopsy was done carefully at a nodular erythematous lesion at the mid-esophagus, 28 cm from the upper incisor using standard-type fenestrated forceps. A 1-mm diameter cup volume of this forceps minimized tissue damage and bleeding. (c) After taking a biopsy, active bleeding occurred at the biopsy site. (d) Bleeding was controlled by clipping using a standard cartridge-housed clip.
Figure 2 Abdomino-pelvic computed tomography scan findings of the liver and esophagus. Submucosal layer of the distal esophagus was edematous and thickened (arrow).
Figure 3 Pathological findings of the esophageal lesion. Thinand thick-walled blood vessels with dilated lumens are observed in the submucosa of the esophagus (HE, ¥40).
lesion at the mid-esophagus, 28 cm from the upper incisor using standard-type fenestrated forceps (Fig. 1B). A 1-mm diameter cup volume of this forceps minimized tissue damage and bleeding. After taking a biopsy, active bleeding occurred at the biopsy site (Fig. 1c). Bleeding was controlled by clipping using a standard cartridge-housed clip (Fig. 1d). Histological findings showed thin- and thickwalled blood vessels with dilated lumens in the submucosa of the esophagus (Fig. 3). The pathological diagnosis was consistent with hemangioma. To rule out syndromes that have abnormal vascular gastrointestinal (GI) tract features (e.g. Osler-Weber-Rendu syndrome, blue rubber bleb nevus syndrome), we carried out chest dynamic CT, brain magnetic resonance image (MRI) and thyroid ultrasonography. No vascular abnormality was detected. The abnormal vasculature was attributed to a simple giant hemangioma that extended from the pharynx to the esophagus. After consultation with an otorhinolaryngologist for evaluation of the risk of hemangioma, no danger was expected as long as the hemangioma did not cause hoarseness, dyspnea or dysphagia. The patient was prescribed regular 6-month follow ups. He has been followed for two and a half years, and there have been no symptoms, nor signs of progression.
DISCUSSION
I
N THE HEAD and neck, hemangiomas usually arise on the parotid gland, tongue and larynx. However, in the present case, the giant hemangioma occupied the pharynx
© 2012 The Authors Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society
628
J. W. Won et al.
and esophagus.2 Esophageal hemangioma is a rare benign vascular tumor. Review of 106 cases of vascular GI tumors from the Mayo Clinic revealed only two hemangiomas involving the esophagus.3 Moersch et al. reported esophageal hemangioma in only three (0.04%) of 7459 autopsy cases.1 Most hemangiomas of the head and neck are congenital, 70% of hemangiomas are present at birth and 85% are noted within the first year after birth.4 Like other head and neck hemangiomas, silent esophageal hemangioma needs no special treatment other than close observation. However, if such a malady was found to not be a simple hemangioma but a varix or other systemic vascular disease, it should be immediately evaluated and treated for a better prognosis. In our case, the hemangioma was incidentally detected during a health check-up of a 42-year-old man, and the features suggested an esophageal varix. Because esophageal hemangioma has the same shape and appearance of varices, it is very difficult to discriminate extensive esophageal hemangioma from varices with an endoscope. However, it is extremely rare in cirrhotic patients that varices are observed in the oropharynx. This is the only differential point. In the present case, endoscopic biopsy fortunately succeeded and no major complications were found. However, it should be noted that there is a known high risk of bleeding and consequential complications following an endoscopic biopsy. Thus, for a differential diagnosis, the presence of liver cirrhosis and endoscopic findings, such as the location of the lesion, should be considered first and foremost rather than the histological evaluation. In a simple hemangioma, variceal ligation will increase the bleeding risk,5 and non-selective beta blockers are recommended. We also analyzed this patient’s CT scan for liver cirrhosis. There are several syndromes that involve GI tract vascular abnormality, including blue rubber bleb nevus syndrome and Osler-Weber-Rendu disease. According to the diagnosis, treatment and prognosis will be different. Therefore, we must distinguish hemangioma from varices or vascular abnormality syndromes. Luminal hemangiomas of the GI tract have been reported as part of blue rubber bleb nevus syndrome.6 This syndrome typically involves the skin and GI system but can involve the central nervous system (CNS), thyroid and other areas. If the disease involves the CNS, it can be fatal.7 Therefore, accurate diagnosis is needed. Patients with personal or family history of Osler-WeberRendu disease may present with multiple esophageal hemangiomas (our patient denied such history).8 OslerWeber-Rendu disease is characterized by arteriovenous malformation (AVM), and the main areas of involvement are the
Digestive Endoscopy 2013; 25: 626–629
nasal mucosa, GI tract, pulmonary vasculature, and brain. The life expectancy of patients with Osler-Weber-Rendu disease and pulmonary AVM or cerebral AVM appears to be significantly lower. Therefore, we carried out brain MRI, thyroid ultrasonography, and dynamic chest CT in the present patient. No other vascular abnormality was found, so the diagnosis was simple esophageal hemangioma. In patients with additional symptoms such as hemangioma bleeding, aero-digestive tract stenosis and cosmetic problems, hemangiomas may require treatment. For treatment of esophageal hemangioma, esophagectomy or tumor enucleation has been carried out. Recently, endoscopic sclerotherapy, laser therapy, and endoscopic mucosal resection have also been reported.9 In addition, in recent studies, the efficacy and response rate of steroid treatment were about 80% in reducing the size and relieving symptoms. However, in patients older than 6 months the response diminishes with age. The efficacy of radiation therapy has also been demonstrated in various reports. Because of the organ-specific late radiation adverse effects and the possibility of secondary malignancy, radiation therapy is usually carried out only after other therapies have failed.10 In the present case, the hemangioma was too extensive for esophagectomy or endoscopic mucosal resection because the bleeding risk was very high. The patient was not demonstrating any other symptoms, including hoarseness, dyspnea, or indigestion; therefore, we decided to observe and follow up regularly. We report a case of extended hemangioma that could have been misdiagnosed as an esophageal varix. Because head and neck hemangioma is uncommon, suspected cases must be differentiated from many other possible diseases, and careful consideration during endoscopy must be undertaken to assure proper distinction between a varix and a hemangioma.
CONFLICT OF INTERESTS
A
UTHORS DECLARE NO conflict of interests for this article.
REFERENCES 1 Sogabe M, Taniki T, Fukui Y et al. A patient with esophageal hemangioma treated by endoscopic mucosal resection: A case report and review of the literature. J. Med. Invest. 2006; 53: 177–82. 2 Kano M, Kameyama K, Hosoda Y, Sugino K, Ito K. A cavernous haemangioma of the thyroid gland. J. Laryngol. Otol. 2005; 119: 828–30. 3 Gentry RW, Dockerty MB, Glagett OT. Vascular malformations and vascular tumors of the gastrointestinal tract. Surg. Gynecol. Obstet. 1949; 88: 281–323.
© 2012 The Authors Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society
Digestive Endoscopy 2013; 25: 626–629
Hemangioma from pharynx to esophagus 629
4 Shpitzer T, Noyek AM, Witterick I et al. Noncutaneous cavernous hemangiomas of the head and neck. Am. J. Otolaryngol. 1997; 18: 367–74. 5 Lebrec D, Poynard T, Hillon P, Benhamou JP. Propranolol for prevention of recurrent gastrointestinal bleeding in patients with cirrhosis:A controlled study. N. Engl. J. Med. 1981; 305: 1371–4. 6 Lopes L, Ramada J, Certo M. Blue rubber bleb nevus syndrome: Capsule endoscopy in a patient with GI bleeding. Gastrointest. Endosc. 2007; 65: 151–2. 7 Park CO, Park J, Chung KY. Blue rubber bleb nevus syndrome with central nervous system involvement. J. Dermatol. 2006; 33: 649–51.
8 Loughry RW. Hemangiomas of the esophagus. Rocky Mt Med. J. 1971; 68: 37–9. 9 Shigemitsu K, Naomoto Y, Yamatsuji T et al. Esophageal hemangioma successfully treated by fulguration using potassium titanyl phosphate/yttrium aluminum garnet (KTP/YAG) laser: A case report. Dis. Esophagus 2000; 13: 161–4. 10 Huang CM, Lee KW, Huang CJ. Radiation therapy for lifethreatening huge laryngeal hemangioma involving pharynx and parapharyngeal space. Head Neck 2013; 35: e98–101.
© 2012 The Authors Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society
