Argon plasma coagulation (APC) is a noncontact technique of electrocoagulation in
which energy is transmitted via ionized argon gas flow. The tip of the catheter should
be kept between 1 mm and 3 mm away from the mucosa. APC has become increasingly popular
for treating gastric antral vascular ectasia (GAVE). Its main advantage is that coagulation
is more superficial, thus reducing the risk of complications [1].
We present two patients who underwent endoscopic APC treatment for anemia secondary
to GAVE. After the third APC session in one patient and after the fourth APC session
in the other both developed a large antral ulcer and the treatment must be discontinued.
These patients were subsequently found to have developed hyperplastic gastric polyps,
8 months and 14 months after the treatment, respectively ([Fig. 1], [2]); their laboratory tests showed hypergastrinemia (1520 pg/mL and 1980 pg/mL, respectively;
normal range < 100 pg/mL).
Fig. 1 Endoscopic image of two antral polyps against a typical background of watermelon stomach,
in which several subepithelial ectasias can be observed in the central mucosa.
Fig. 2 Histological views showing a polypoid formation with branching, dilated, and tortuous
hyperplastic foveolae (hematoxylin and eosin [H & E] stain, original magnifcation
× 1) (a), and a higher-power view showing hyperplastic gastric foveolae in an intensely inflammatory
stroma (H & E stain, original magnification × 4) (b).
Hyperplastic gastric polyps developing after electrocoagulation treatment of GAVE
were first reported after endoscopic Nd:YAG laser treatment [2]. Hyperplastic gastric polyps occurring after APC treatment for GAVE are rare [3]. APC is a more superficial method of coagulation, implying lower thermal aggression.
Several circumstances can increase thermal injury during this treatment, such as repeat
coagulation of specific areas or the use of high-energy settings. However, the most
important cause is contact between the tip of the catheter and the mucosa during the
procedure. When this happens, temperatures can reach 100 °C, causing deep coagulation
with cell vaporization and significant thermal injury [4].
Hypergastrinemia, one of the factors linked to the development of GAVE [5], might also play an important role in the development of hyperplastic gastric polyps.
Gastrin stimulates gastric mucosa cell growth, and this could increase the response
of the gastric mucosa to injury.
To conclude, we must be aware that APC treatment for GAVE can lead to the development
of hyperplastic gastric polyps, as a reaction of the mucosa to thermal injury. The
development of these polyps is favored by hypergastrinemia. Refined APC techniques
which avoid thermal injury will help to prevent this complication.
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