Introduction
The patient’s abdominal pain The etiology is extremely rare, and it is easy to be misdiagnosed as gastrointestinal stromal tumor (GIST).
Case data
Patient, female, 46 years old , previously healthy, presented to the surgical outpatient clinic for intermittent epigastric pain without associated weight loss or anorexia. The patient’s medical history revealed a diagnosis of symptomatic mild gastroesophageal reflux disease 3 years earlier and intermittent antacid therapy. The patient does not smoke or drink alcohol.
Physical examination: Deep palpation revealed a firm, nontender mass in the upper abdomen, but otherwise normal. Abdominal ultrasound at the bedside suggested a possible pancreatic mass. Abdominal CT with IV contrast showed a 9 x 7 x 7 cm lobulated, hypervascular, exophytic solid mass extending from the stomach to the sac (Figures 1 and 2).
Figure 1 >
Figure 2
No gastric mucosa connection or necrosis. There was no ascites, lymphadenopathy, or metastases. Complete blood count, liver and kidney function tests, and tumor markers (CA19.9, AFP, CEA) were all within the normal range.
The patient underwent CT-guided core needle biopsy without complications. What should be the diagnosis?
Analytical Diagnosis
Biopsy showed vascularized plexiform There were spindle cells in the interstitium, no cellular atypia, and a low mitotic rate (Figure 3). Immunohistochemistry showed positive for smooth muscle actin (SMA) (Figure 4), CD34, CD117, DOG-1 and ALK (excluding gastrointestinal stromal tumor and inflammatory myofibroblastic tumor), S100 and β-catenin (excluding schwannomas and fibromatosis) and MUC4 (excluding fibromyxoid sarcoma) were negative.
Figure 3 >
Figure 4
The diagnosis result is: gastric plexus fibromyxoma (PF).
Knowledge class: Gastric plexiform fibromyxoma
< span>PF is a rare gastrointestinal mesenchymal tumor, a benign tumor that usually occurs in middle-aged women. The clinical manifestations of PF are non-specific, and patients often seek medical attention due to gastrointestinal bleeding, melena, abdominal pain, epigastric discomfort, abdominal distension, or abdominal mass.
PF is easily misdiagnosed as GIST, and attention should be paid to identification. GIST is the most common gastric mesenchymal tumor and may be malignant. Since the clinical, endoscopic, and imaging features of PF and GIST are not specific, immunohistochemistry is required to differentiate them. Although GIST can be positive markers such as SMA, calponin, and S100, GIST more specifically expresses CD117, DOG-1 and CD34 as an important diagnostic basis, and can detect c-Kit or PDGFRA gene mutations.
Currently, the main treatment for PF is partial gastrectomy or partial gastric wedge resection. Surgery remains the treatment of choice for this disease due to its plexiform growth pattern with ill-defined boundaries. The current case follow-up has a good prognosis, and no recurrence or distant metastasis has been found. However, vascular invasion has been reported in individual cases in the literature. Therefore, the prognosis of the disease still needs to be confirmed by further research.