GTs arising from the small intestine are extremely rare. So far, only 8 cases have been described in the English literatures [3–5]. Among them, two cases located at the duodenum, one case at jejunum, and five cases at the ileum. The clinicopathologic features of small intestinal GTs are summarized in Table 1. The case reported in our study is a 30-year-old female. Together with this case, the sex distribution is basically balanced (5 males and 4 females). Small intestinal GTs usually present non-specific symptoms such as abdominal pain and intestinal bleeding (melena or hematochezia). Larger tumors can cause intestinal stenosis and obstruction.
Table 1
Clinicopathological characteristics of documented small intestinal GTs
Reference | Age/Sex | Location | Size in cm | Invasion | Treatment | Immunohistochemistry | Nature | Outcome |
Chen et al. 2020 [3] | 73/F | Ileum | 2.0*2.8*1.2 | Muscularis propria | Laparoscopic resection | SMA(+), vimentin(+),caldesmon(+), CD34(+), Ki-67 (80%+), CD117(-), desmin(-), Dog-1(-), S100(-), leukocyte common antigen (-), cytokeratin(-) | Malignant | Metastasis,Died |
Ma et al. 2020 [4] | 58/M | Ileum | 6.0*5.0 | Serosa | Laparoscopic resection | SMA(+), Ki-67(70%), CD34(+), Nestin(+), EMA(-), CD117(-), Dog-1(-), S100(-), desmin(-) | Malignant | Liver metastases |
Campana et al. 2014 [5] | 51/M | Ileum | 3.7 | Serosa | Laparoscopic resection | Ki-67 (< 5%+) | Benign | Follow-up |
Abu-Zaid et al. 2013 [6] | 29/F | Ileum | 12.8*10.2*13.1 | Whole layer | Surgical resection | SMA(+), collagen type IV(+), caldesmon(+), calponin(+), CD117(-), CD34(-), S100(-), cytokeratin(-), desmin(-), HMB-45(-), chromogranin(-), synaptophysin(-) | Malignant | Follow-up |
Knackstedt et al. 2007 [7] | 65/M | Duodenum | Not available | Submucosa | Endoscopic mucosal resection | SMA(-), CD117(-), CD56(-) | Benign | Follow-up |
Shelton et al. 2007 [8] | 48/F | Ampulla | 3.0 | Minimal invasion of common bile duct and pancreatic duct | Whipple | Not available | Malignant | Unknown |
Geraghty et al. 1991 [9] | 60/M | Ileum | 0.6 | Serosa | Surgical resection | SMA(+), desmin(-), chromogranin(-), euron-spectificendase(-) | Unknown | Die of unrelated causes |
Hamilton et al. 1982 [10] | 82/M | Jejunum | 1.0*1.5 | Not available | Surgical resection | Not available | Unknown | Unknown |
Due to the deep location and non-specific symptoms, small intestinal tumors including GTs are usually hard to differentiate and diagnose. Abdominal contrast-enhanced CT may be useful to distinguish GTs from other small intestinal tumors. According to previous description (mainly on gastric GTs), hemangioma-like globular enhancement with central fill-in and persistent homogeneous enhancement were both visualized in GTs [11]. As for the reported case, the tumor on contrast-enhanced CT showed homogeneous high attenuation in the arterial, venous, and delayed phases. GTs in gastric usually display a submucosal pattern of growth. In the case reported by Knackstedt C et al., the GT located in duodenal bulb was polyp-like [7]. Shelton JH et al. reported a GT of the ampulla, in which a protruding mass was seen [8]. However, until now, there is no enteroscopic image presented in the jejunum or ileum GTs. In this paper, for the first time, we acquired the endoscopic imaging of small intestinal GT by balloon-assisted enteroscopy. Intriguingly, the enteroscopic imaging showed a fibrous capsule-covered mass, without any epithelial coverage, and on the surface of the tumor, no definite hemorrhage, erosions or ulcers were observed. Only some minor erosions on the area around the tumor edge were seen, which may cause the persistent melena.
Most GTs depend on postoperative pathological diagnosis. Under the microscope, the tumor consists of a large number of smooth muscle bundles and dilated capillaries. Immunohistochemically, tumor cells were stained positive for SMA and collagen type Ⅳ. Negative CD117 and DOG-1 expressions help in excluding the diagnosis of gastrointestinal stromal tumors, while negative CgA and Syn expressions help in excluding neuroendocrine neoplasms [12]. Criteria for malignant GTs proposed by Folpe et al. include tumors with a deep location and a size of more than 2 cm, or atypical mitotic figures, or moderate to high nuclear grade and ≥ 5 mitotic figures/50 HPF [13]. According to the criteria, the present case was considered as low possibility of malignancy. And 6 months follow-up showed no indication of recurrence or metastasis after a partial enterectomy, which supporting the benign diagnosis.
All the small intestinal GTs recorded in the literature have received surgical resection, but no patients received regional lymphadenectomy. After surgery, also no patients received adjuvant radiotherapy or chemotherapy. However, 2 patients developed metastases in the 8 reported cases. Therefore, standardized systemic treatment needs to be further studied. For gastric GTs, endoscopic or laparoscopic resection is recommended. Also due to the fact of extremely rare cases of malignant GTs in gastric, no standardized neoadjuvant or adjuvant treatment was suggested. Radiotherapy or chemotherapy has been utilized for the treatment of malignant GTs of head and neck. However, in the reported cases, tumor progression was not reliably altered [14].