S-03-5
Current Status of Digestive Endoscopic Electrosurgical therapy withArgon Plasma Coagulation (APC)
アルゴンプラズマ凝固装置を用いた消化器内視鏡手術の現状
Toru Niwa1, Yuzuru Ikehara2, Masao Ichinose1
丹羽 徹1, 池原 譲2，一瀬雅夫1
1.

Graduate School of the second internal Medicine, Wakayama Medical University
811-1 kimiidera , Wakayama city , Wakayama , 641-8509, Japan
和歌山県立医大大学院研究科 第二内科 〒641-8509 和歌山市紀三井寺811-1
2. Research Center for Medical Glycoscience, National Institute of Advanced Industrial
Science and Technology, Open Space Laboratory Central-2,1-1-1 Umezono, Tsukuba, Ibaraki 305-8568
産業技術総合研究所 糖鎖医工学研究センター 分子医用技術開発チーム〒305-8568 つくば市梅園1-1-1 産総研中央第２ OSL

Electrosurgery is used in the majority of endoscopic therapeutic procedures. Various endoscopic devices
have been developed following endoscopic development. Argon plasma coagulation (APC) is mainly usedfor coagulating superficial vascular lesions, such as sporadic angiodysplasias, gastric antral vascular ectasia(GAVE) and radiation proctitis. APC has been used for various situations such as ablation of residual polyptissue after pieacemeal resection of large sessile polyps, pappilative ablation of tumors, in particular tissue
ingrowth/ overgrowth of esophageal stent. Endoscopic ablation is discussed in the context of Barrett’s
esophagus with frequent reports in medical journals. Some reports have indicated that APC was effective
in completely eradicating in 58%-100% of cases. Serious complications and less severe side effects havebeen reported. However, the effectiveness of APC for HDG in Barrett’s esophagus is controversial. Further
experiment and development are needed to establish endoscopic ablation therapy for HDG or early-stage
malignancies.

means that heating of cellular water occurs soElectrosurgery is used in the majority ofendoscopic

therapeuticendoscopic

devices

procedures.

havebeen

following endoscopic development.

Variousdeveloped,

rapidly that cell burst. In endoscopic therapy, theproportion of cells coagulated to those cut can bevaried.

Elctrosurgery

Argon plasma coagulation (APC) is a noncontact,is based on the transformation of energy from highmonopolar, elactcoagulation technique that works

frequency electric current into heat, with theby applying high frequency current to the tissues

resulting effect of cutting and/or coagulating tissue

through ionized argon, an inert gas that requires toat the point of current application. As current passes

be ionized to conduct current. APC is particularly

through tissue, electrons collide with various tissue

useful in treating large surface areas. Compared

components. During these collisions, a certain

with contact methods of coagulation, APC provides

amount of energy is dissipated depending on thea more homogeneous tissue effect and can treat

nature of the material traversed and results in a riselarge surface area rapidly. However, it may harbor ain temperature. Electrosurgical waveforms arelower perforation risk because the penetration depth

mainly divided two types depending on the tissue

is limited to 1-3mm.

effects,

whicharecoagulation

andcutting.

For clinical endoscopic therapy, APC is mainly

Coagulation means that temperature rises within

used for coagulating superficial vascular lesions,cells, which then dehydrate and shrink. And cutting

such as sporadic angiodysplasias, gastric antral

vascular ectasia (GAVE) and radiation proctitis.

recommend APC for routine care for HGD in
Barrett’s esophagus.

Attwood SE et al. reported

that Barrett’s esophagus and HGD with a response
in 25 of 29 patients (86%), and four patientsdeveloped cancer and repeated APC ablation.
Practically, in the most cases of HDG patients,
endoscopic mucosal resection (EMR) or endoscopic
submucosal dissection (ESD) are carried out withelectrosurgical high frequency electric current
knives. ESD is new endoscopic technique, whichenables en bloc resection. However, the techniqueof ESD is not yet standardized. So, endoscopists
mainly rely on personal or reported experience thus
And also, APC has been used for variousfar.

situations, ablation of residual polyp tissue after

Endoscopic ablation therapy with APC is expectedpieacemeal resection of large sessile polyps,

to be viable alternative to surgical dissection or

pappilative ablation of tumors, in particular tissue

EMR/ESD

ingrowth/ overgrowth of esophageal stent.

malignancies including HGD in Barrett’s esophagus,Recently, APC is also used for endoscopic ablation

especially in high risk patients. Further experiments

device.

andAblationmeansremovingabnormal

growths or harmful substances by mechanicalforimprovement

dysplasiaareandneeded

early

tostageestablish

endoscopic ablation therapy with APC.

manners. Endoscopic ablation is discussed in thecontext of Barrett’s esophagus with frequent reports
in medical journals.

Some reports have indicatedthat APC was effective in completely eradicating in58%-100% of cases. Serious complications and lesssevere side effects have been reported. Perforation
was reported in 0%-3.6% of cases. Other serious
adverse events include stricture and major bleeding
was reported in 0%-15%. At this time, routine
ablation of nondysplastic Barrett’s esophagus of
APC is not recommended because of the relatively
high incidence of complications, low rate ofprogression to cancer, and lack of long-term data on
effectiveness of eradication in preventing cancer
progression.
Ablation of high grade dysplasia (HGD) in
Barrett’s esophagus with APC has been studied, but
the limited data can be available. So, it is difficult toReferences[1] Lenz L, Taferel J, et al; Endoscopy. 43(2011),
697-701.
[2] Dumot JA, Greenwald BD; Endoscopy. 40(2008),
1026-1032.
[3] Rey JF, Beilenhoff U, Neumann CS, Dumonceau
JM; Endoscopy, 42(2010), 764-771.
[4] Attowood SE, Lewis CJ, Caplin S et al; Clin
Gastroenterol Hepatol. 1 (2003), 258-263.
[5] Morris ML, Tucker RD et al; Am J Gastroenterol.
104(2009), 1563-1574