1 . Stenting for Lung Cancer with AERO Hybrid Pulmonary Stent

Division of Respiratory Medicine, Department of Internal Medicine, St.Marianna University School of Medicine
Teruomi Miyazawa

Abstract
AERO hybrid pulmonary stent is indicated for use in the treatment of tracheobronchial obstruction by lung cancer. AERO hybrid stents are easy to deploy and remove.
Hybrid stent has characteristics of both metallic framework (laser cut nitinol alloy) and fully covered polyurethane coating.
Hybrid stent can be placed via flexible or rigid bronchoscopy.

Key words

• AERO hybrid pulmonary stent
• Tracheobronchial obstruction
• Lung cancer

2. Endoscopic Biliary Stenting for Unresectable Malignant Biliary Obstructions

Department of Gastroenterology, Gifu Municipal Hospital
Tsuyoshi Mukai

Abstract
Endoscopic biliary stenting (EBS) is a well-established palliative treatment for unresectable malignant biliary strictures, for which plastic tube stents (PSs) and self-expandable metallic stents (SEMSs) are most commonly used. EBS plays an important role in maintaining patients’ condition and in determining subsequent prognosis and quality of life. SEMSs are expected to be more suitable for unresectable malignant biliary strictures according to the Japanese guidelines. SEMSs also proved more advantageous in reducing the number of reintervention sessions and the overall treatment cost. However, U-SEMSs are usually difficult to remove after placement and thereby, limit reintervention in cases of U-SEMS obstruction.
Selection of an SEMS with longer patency than a PS is expected to increase the number of cases that benefit from SEMSs. However, if U-SEMS placement or reintervention for U-SEMS obstruction is unsuccessful, patient relief from the condition and determining the subsequent prognosis and quality of life of patients might be impossible.
Therefore, easy, safe, and effective U-SEMS placement and familiarization with the U-SEMS placement with consideration of the reintervention are necessary. In this regard, covered SEMS is a better choice for patients with unresectable malignant distal biliary because its addresses the issue of removability.

Key words

• Endoscopic biliary stenting（EBS）
• Malignant biliary stricture
• Self-expandable metallic stent（SEMS）

3.Stenting for Gastrointestinal Malignant Stenosis

Bilio-pancreatology Section, Sapporo Kousei General Hospital
Atsushi Hirayama, Hiroyuki Miyakawa, Tatsuya Nagakawa, Keiya Okamura, Daiki Oku, Shou Kitagawa

Abstract
In the clinical course of inoperable pancreatic cancer, gastric cancer, malignant gastric outlet obstruction (GOO) is a phenomenon experienced at high frequency, which is an important phenomenon that lowers QOL.
Endoscopic gastroduodenal stent placement is approved as a treatment for GOO in Japan in Japan.
The difficulty of the procedure has been marke lowered, and it has become possible to place it without stress. It has evaluated to be minimally invasive and makes it possible to resume early oral intake, and the number of such cases has increased in recent years.
However, the problem is that predicting invalid cases of gastroduodenal stent placement beforehand is to predict the existence of a few irreversible complications and the examination of the treatment for the trouble of the bile duct is inadequate and difficult to do. In this paper, we will consider the current state of endoscopic upper gastrointestinal stenting based on our own experiments and literature considerations and outline the future prospects.

Key words

• Duodenal stent
• Gastrointestinal malignant stenosis
• Pancreatic cancer

4.Colonic Stent for Malignant Colorectal Obstruction

Department of Surgery, Toho University Ohashi Medical Center
Yoshihisa Saida

Abstract
Stent (SEMS: self-expandable metallic stent) treatment for the colon and rectum finally became available beginning in 2012 in Japan within the public health insurance system. In this review, we describe the present conditions and future prospects taking data from the literature into consideration. The current indication in Japan is malignant colorectal stenosis including palliation and serving as a bridge to surgery (BTS).
Colonic stenosis is not rare in the terminal period in the cancer patient. As palliative treatment, colonic stenting is becoming popular as an alternative to colonic stoma. Colonic stent not only prevents stoma creation, but also achieves quick intestinal decompression without any discomfort such as abdominal pain. However, during follow-up after the stent, complications might occur in 30~40% of patients. It is important to create a system with endoscopists and surgeons which can support re-intervention and surgery.
In BTS, short duration of hospitalization, as well as reduced postoperative complications, colostomy rate, and mortality rate are expected as compared to emergency surgery. Although it has been reported that the complication rate is low, adequate preparation and informed consent are important because complications can still occur. There are some tips and points to be taken into consideration to achieve safe procedures. The occurrence of complications can be minimized by following these. The Colonic Stent Safe Procedure Research Group, one of the subordinate organizations of the Japan Society for Gastrointestinal Endoscopy, has put together a set of mini-guidelines for use of the colon stent, and the mini-guidelines have been published on the Society's website.
The long-term prognosis is still unknown in BTS, and even the ESGE clinical guidelines do not recommend BTS as a standard treatment. A large prospective study is needed.

Key words

• Colonic stent
• Malignant colorectal obstruction
• BTS（bridge to surgery）

Case Reports

Two Cases of Neurofibromatosis Type 1 with Spontaneous Rupture of the Inferior Mesenteric Artery Treated with Transcatheter Arterial Embolization

Department of Radiology and Surgery¹⁾ and Emergency²⁾ National Hospital Organization Kumamoto Medical Center
Ayumi Iyama, Takanori Negishi, Koya Iwashita, Shota Tanoue, Hidetaka Sugihara¹⁾,
Kohei Karino²⁾, Shunji Yoshimatsu

Abstract
Neurofibromatosis type 1 (NF-1) is infrequently associated with vascular lesions. We here report two patients with NF-1 who developed retroperitoneal bleeding caused by spontaneous rupture of the inferior mesenteric artery (IMA) and were successfully treated with transcatheter arterial embolization (TAE). Case 1 was a man in his 70s with NF-1 who presented with low back pain of sudden onset. Contrast-enhanced computed tomography (CT) and angiography showed a pseudoaneurysm and extravasation of contrast medium from the superior rectal artery. Embolization was performed using coils and n-butyl-2 cyanoacrylate (NBCA). Case 2 was a woman in her 60s with NF-1 who presented with low back pain and loss of consciousness. Contrast-enhanced CT and angiography showed a pseudoaneurysm at the bifurcation of the left colic branch. Embolization was performed using coils. In both cases, the hemorrhage was successfully terminated by TAE without complications. Non-traumatic vascular collapse caused by rupture of the IMA is extremely rare. It is important to keep in mind that underlying diseases such as NF-1 can be associated with fragile vessel walls. TAE may be the treatment of choice for arterial complications in patients with NF-1. An extremely careful catheter approach is necessary in patients with fragile vessel walls.

Key words

• Neurofibromatosis type 1
• Inferior mesenteric artery
• Transcatheter arterial embolization (TAE)