CFT was reported first as a rear benign soft tissue tumor in children by Rosenthal and Abdul-Karim [1, 2], which was previously named as “calcifying fibrous pseudotumors” as an abnormal reaction in the healing process of tissues [7]. The World Health Organization (WHO) established the name for this lesion in 2002 as “CFT” in the newly published classification of tumors of soft tissue and bone [8]. CFT has female predominance (M:F = 1:1.27) and is typically found between 20 and 30 years of age [2]. Gastrointestinal CFTs, including stomach and small intestine, are rare [9,10,11,12,13]. Most cases with gastrointestinal CFTs are asymptomatic. The cause of CFT is thought to be related to previous infection, history of trauma, and surgical intervention; however, the definitive mechanism or causes have not been confirmed. A relationship to genetic factors was suspected because of familial CFTs [14]. Although gastrointestinal CFTs are benign mesenchymal tumors for which local resection may be sufficient, they are difficult to distinguish from gastrointestinal submucosal tumors such as GIST, schwannomas, and leiomyomas [2, 15]. Furthermore, CFT does not metastasize and has a low risk of recurrence [2, 16, 17]. Histological characteristics of CFT include calcifying psammoma bodies in abundant dense fibro-collagenous tissue, collection of lymphocytes, and occurrence of plasma cells [2, 7, 15].
Recently, thickening of the gastrointestinal wall and an IgG4-related pseudotumor have been considered to suggest a gastrointestinal lesion of IgG4-related disease [3, 4]. IgG4-related disease is diagnosed in the presence of diffused/localized swelling or masses in a single or multiple organs with the elevation of serum IgG4 levels more than 135 mg/dl, or for histological findings of abundant infiltration of IgG4-positive plasma cells and lymphocytes along with fibrosis [6]. In the current case, although IgG4-positive cells were found on pathological examination, postoperative serum IgG4 levels were normal (26 mg/dl). Some reports show IgG4 positive cells in gastrointestinal CFTs, but IgG4-related disease was not confirmed [3]. Nevertheless, it is important to suspect IgG4-related disease and to monitor the serum IgG4 levels in such cases.
In our case, the preoperative differential diagnosis of SMT was a non-epithelial mesenchymal tumor such as GIST and leiomyoma based on endoscopic findings and EUS appearance. As a preoperative diagnosis, GIST with calcification was highly suspected. Then we performed gastric wedge resection via LECS. LECS is considered a good adaptation for small SMTs, although gastric wedge resection is a standard treatment for GIST [18]. Since CFT is a benign tumor, the risk of metastasis or recurrence is limited. However, the recurrence of cervical CFT has been reported [2, 16, 17]. For curative resection of CFT, sufficient surgical margins in surgery are necessary. When CFT is suspected, the patient should be tested for IgG4-related disease. The relation of IgG4-related disease and IgG4-related pseudotumor should be analyzed in large studies. The patient in this report remains well with no evidence of tumor recurrence for 2 years after resection. To the best of our knowledge, this is the first report that has described using LECS to treat a gastric CFT.
In conclusion, we herein reported a gastric CFT treated by laparoscopy and endoscopy cooperative surgery that was suspected to be a IgG4-related disease.