A 4-month-old boy with gastrointestinal stromal tumor of mesocolon

Abstract

Gastrointestinal stromal tumors (GISTs) are very uncommon in pediatric patients, and they are distinct clinical-pathological and molecular deviations from their adult counterparts. Most pediatric GISTs lack the c-kit or platelet-derived growth factor receptor alpha (PDGFRA) genes mutations. To date, there is no published standard guidelines available for the best treatment of pediatric GISTs, especially for infant GIST. Therefore, we report a case of 4-month-old infant with GIST of mesocolon without KIT/PDGFRA mutation. We also review the clinical, biological, and genetic features of pediatric GISTs and re-think several questions that could affect clinical practice.

Keywords: CCND2; GIST; PTCH1; adult; imatinib; pediatric; young.

Figure 1.

Abdominal contrast-enhanced computed tomography scan showed a tumor (diameter, 4.6cm× 6.3cm) located in mesocolon.

Figure 2.

Hematoxylin–eosin staining showed spindle cell morphology.

Figure 3-5

Immunehistochemical analyses were positive for CD117 (Fig.3), PDGFR (Fig.4), Vimentin (Fig.5).

Figure 6.

Immunehistochemical analyses showed negative for the expression of succinate dehydrogenase B (SDHB).

Figure 7-8.

Mutational analysis showed a wild type for KIT (exons 9, 11, 13, 17, 18) (Fig.7) and HER2 (HER2/CEP17 1.0) (Fig.8).

Figure 9.

Re-image found metastases of omentum, mesentery, retroperitoneum, inguinal lymph node and abdominal wall two months after surgery.