Endoscopic submucosal dissection of a solitary gastric plasmacytoma: “third space oddity”

Although well established for classic indications [1] [2] [3], the use of endoscopic submucosal dissection (ESD) can help to solve rare clinical situations [4] [5].

A 35-year-old woman without medical history underwent an esophagogastroduodenoscopy for progressive epigastralgia that was unresponsive to proton pump inhibitors (PPIs) for 12 months. A 10-mm subepithelial lesion in the antrum was reported ([Fig. 1]). Biopsies revealed an extramedullary plasmacytoma, confirmed by expert pathology. Apart from weight loss, attributed to epigastralgia, no other B symptoms were present. Diagnostic work-up disclosed a unique gastric hypermetabolic focus on positron emission tomography ([Fig. 2]). There were no biological anomalies. Bone marrow biopsy was normal.

Fig. 1 Endoscopic image showing a subepithelial antral lesion.

Fig. 2 Coronal positron emission tomography image showing a hypermetabolic focus at the stomach.

Endoscopic evaluation 1 month after radiotherapy, administered with curative intent (40 Gy), suggested a non-responding lesion ([Fig. 3]). Endosonography evaluation showed a homogeneous, hypoechoic mass (12.0 × 5.7 mm) limited to the submucosa ([Fig. 4]). ESD was proposed as a treatment option in a multidisciplinary team.

Fig. 3 Endoscopic image showing subepithelial antral lesion 1 month after completion of radiotherapy (20 × 2 Gy).

Fig. 4 Endoscopic ultrasound image (underwater) of a homogeneous, hypoechoic mass (12.0 × 5.7 mm) limited to the submucosa.

Lesion delineation was obtained using narrow-band imaging (NBI) and texture and color enhancement imaging. ESD was performed by expert hands ([Video 1]) with a GIF-HQ-190 gastroscope, using an electrosurgical knife and glycerol solution. The conventional ESD technique was applied, taking 1-cm lateral margins, dissecting alongside the proper gastric muscular layer under near focus and texture and color enhancement. En bloc resection (60 × 40 mm) was obtained in 150 minutes. No post-radiotherapy fibrosis was noted. Pathology confirmed the presence of a 21-mm submucosal lambda monoclonal plasmacytoma infiltrating up to 1 071 micrometers. Lateral and vertical margins were free, even though free deep submucosa was only 50 micrometers on the specimen ([Fig. 5]). Endoscopic evaluation at 6 months showed post-ESD scarring without signs of relapse ([Video 1]), while the patient reported minor residual epigastralgia but regained normal weight. Albeit the outcome is reassuring, close endoscopic and imaging follow-up is proposed.

Video 1 Endoscopic submucosal dissection of a solitary gastric plasmacytoma: “third space oddity”.

Fig. 5 Pathology images. a Macroscopic picture of the resected specimen showing the subepithelial lesion (red dotted circle) and 1-cm margins. b Inflammatory infiltrate located mainly in the mucosa and submucosa. c At higher magnification, histopathological aspect of inflammatory cells (eccentric nucleus with coarse chromatin and cart wheel pattern) suggests diffuse infiltration by plasma cells. d Anti-CD138 immunostaining confirms inflammatory nature of plasma cells. e, f In situ hybridization shows lambda monoclonality.

Although rare, ESD (alone or complementary to other treatment modalities) can serve as an adequate treatment for digestive plasmacytoma beyond the scope of its classic indications.

Endoscopy_UCTN_Code_CCL_1AB_2AD_3AB

Competing interests

The authors declare that they have no conflict of interest.

• References

• 1 Pimentel-Nunes P, Dinis-Ribeiro M, Ponchon T. et al. Endoscopic submucosal dissection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline. Endoscopy 2015; 47: 829-854
• 2 Draganov PV, Wang AY, Othman MO. et al. AGA Institute Clinical Practice Update: Endoscopic Submucosal Dissection in the United States. Clin Gastroenterol Hepatol 2019; 17: 16-25
• 3 Ono H, Yao K, Fujishiro M. et al. Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer (second edition). Dig Endosc 2021; 33: 4-20
• 4 Park CH, Lee SM, Kim TO. et al. Treatment of solitary extramedullary plasmacytoma of the stomach with endoscopic submucosal dissection. Gut Liver 2009; 4: 334-337
• 5 Park SY, Moon HS, Seong JK. et al. Successful treatment of a gastric plasmacytoma using a combination of endoscopic submucosal dissection and oral thalidomide. Clin Endosc 2014; 6: 564-567

Publication History

Article published online:
10 March 2022