Large incidental gastrointestinal stromal tumors in a patient presenting with acutely symptomatic nephrolithiasis: A case report

Abstract

Gastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms, representing approximately 1%-2% of all primary gastrointestinal malignancies. Incidental GISTs are often less than 1 cm when discovered and have been reported predominantly in obese patients undergoing surgery for other medical indications. We present the rare case of a large incidental GIST in a nonobese patient with acutely symptomatic nephrolithiasis. Large GISTs may be treated with neoadjuvant imatinib mesylate to reduce tumor size prior to surgery, though some tumors may experience little change in size despite effective treatment. Treatment response for GISTs can be monitored via imaging studies, such as computed tomography or magnetic resonance imaging, but computed tomography is generally preferred over magnetic resonance imaging.

Keywords: Choi criteria; Large GIST; RECIST.

Fig. 1

Axial, sagittal and coronal CT images of the abdomen demonstrate a 13 × 5 × 10.5 cm heterogeneously enhancing mass (blue arrows) abutting anterior wall of the stomach (green arrows) and the left hepatic lobe (red arrows) and a 0.3 cm nonobstructing left renal calculus (yellow arrow). (Color version of figure is available online.)

Fig. 2

Gastrointestinal stromal tumor, spindle cell type. The tumor is moderately cellular and composed of uniform spindle cells in a hyalinized matrix (H&E, ×100).

Fig. 3

Gastrointestinal stromal tumor, spindle cell type. Higher magnification shows spindle cells with elongated nuclei, inconspicuous nucleoli and a moderate amount of eosinophilic cytoplasm (H&E, ×400).