Gastric cardia submucosal tumours – histopathological diagnosis and challenges in management

A 74-year-old female presented with epigastric pain. A submucosal lesion of the gastric cardia and small hiatus hernia were identified on gastroscopy (Fig. 1). Superficial biopsies were inconclusive. Endoscopic ultrasound identified a 2 cm, well-defined and lobulated submucosal lesion. Sharkcore deep biopsies confirmed a leiomyoma with spindle cells which were positive for desmin on immunohistochemistry (with absence of CD117 and DOG1). Computed tomography (CT) confirmed a gastric cardia submucosal lesion with adherence to the left diaphragmatic crura (Fig. 2). She underwent laparoscopic enucleation of a 6 × 4 cm gastric leiomyoma with primary repair and achieved a satisfactory functional and histological result. This case underpins the importance of histopathological diagnosis for submucosal lesions and challenges/considerations for those that are near the gastroesophageal junction (GOJ).

Most submucosal tumours are gastrointestinal stromal tumours (GIST) or leiomyomas.¹ They are indistinguishable without histological diagnosis as highlighted in Figure 1. Accurate diagnosis is key to applying the correct treatment principles.² Our patient's symptomatic 2 cm leiomyoma prompted enucleation. This was challenging due to lesion mobility – addressed by approaching the lesion from above and below (two myotomies) and retracting it with a silk stitch. Lesion adherence to the mucosa led to two mucosal breaches, likely related to the multiple preoperative biopsies taken, including superficial biopsies which are often non-diagnostic.² ≥2 cm GISTs require resection and being near the GOJ, this can be achieved with a laparo-endoscopic extra-gastric or trans-gastric approach.^{3, 4} There a two key differences between GIST and leiomyoma resectional management. Firstly, the malignant potential of GISTs leads to both a lower threshold for resection and the stronger importance of a clear margin.⁵ Secondly, the option of tyrosine kinase inhibitors (TKI) for GIST in either the neoadjuvant setting to achieve resectability or the adjuvant setting to reduce the risk of recurrence.⁶ A laparo-endoscopic resection (not enucleation) would have been utilized if our case was diagnosed preoperatively as a 2 cm GIST.^{3, 4}

Submucosal tumours near the GOJ are challenging to resect as there is risk of stenosis, reflux and leak.³ Surgical approach is impacted by tumour location, size and pathology. The lesion had more than doubled in size at time of surgery (3 months later). Adherence to the left crus and a concurrent hiatus hernia (Fig. 1) meant hiatal and mediastinal mobilization was required to allow assessment and planning of the surgical approach. Neoadjuvant TKI may have been considered if the lesion was known to be >5 cm and potentially locally invasive.⁶ The authors recommend intraoperative endoscopy for multiple reasons including: pre-resection planning, evaluation of relationship with the GOJ and to act as a bougie during resection/repair to avoid stenosis.³ Specific postoperative care recommendations are centred on the site of repair being a high-risk zone for leak. These include: remaining nil per mouth with a nasogastric tube until leak is excluded on imaging (oral contrast CT or barium swallow), regular proton pump inhibitors, monitoring of the c-reactive protein trend and outpatient clinic follow-up at 6 weeks postoperative to evaluate for GOJ stenosis.

Preekesh Suresh Patel: Conceptualization; data curation; formal analysis; visualization; writing – original draft. Michael Rodgers: Supervision. Suheelan Kulasegaran: Conceptualization; data curation; formal analysis; supervision.