Gustavo Dos Santos Fernandes, MD

Gastrointestinal stromal tumors (GISTs) originate from the interstitial cells of Cajal or a precursor and are the most common mesenchymal neoplasms of the gastrointestinal (GI) tract.[1] Although GISTs often present as localized masses, they are typified by a high risk of metastatic relapse, most commonly in the liver and peritoneum.

The human epidermal growth factor receptor 2 (HER2) is a transmembrane receptor with tyrosine kinase activity overexpressed in about 20% to 25% of invasive carcinomas of the breast.