Bladder extragastrointestinal stromal tumor in an adolescent patient: A case-based review

A radiation-related second primary gastrointestinal stromal tumor in the bladder

A 69-year-old man underwent 78 Gy/39 Fr of intensity-modulated radiation therapy for prostate cancer. Seven years after radiotherapy, a nonpapillary bladder tumor was identified. Transurethral resection of the bladder tumor was performed, and the pathological diagnosis was spindle cell sarcoma. Immunostaining revealed KIT-, DOG1++, CD34-, Actin++, Cytokeratin-, Desmin-, S100 protein-, and Vimentin++. No tumor recurrence was observed until 17 months after tumor resection. DOG1 is strongly and specifically expressed in gastrointestinal stromal tumors. This was a rare case of bladder gastrointestinal stromal tumor as a radiation-related second primary tumor.

Primary Extragastrointestinal Stromal Tumor of Greater Omentum with Intraperitoneal Bleeding

Gastrointestinal stromal tumors (GISTs) develop in the digestive tract, mainly in the stomach, small intestine, colon, or esophagus. However, primary tumors with the same pathologic features as GISTs have been reported to occur outside of the digestive tract and are called extragastrointestinal stromal tumor (EGIST). We herein report a rare case of EGIST arising from the greater omentum in a patient with abdominal pain caused by intraperitoneal bleeding from the tumor.

Recurrent and metastatic extragastrointestinal stromal tumors of the mesentery with C-KIT and PDGFRA mutations: a case report

EGISTs originating outside the gastrointestinal tract share some similarities with the GISTs regarding their immunohistochemical features including the positive expression of CD117 and CD34. The majority of EGISTs carry activating mutations of the C-KIT or PDGFRA genes. However, there is no precedent in the literature where the two mutations occur in one case of EGISTs to date. We describe herein, a 52-year-old female who presented as mesenteric and pelvic regions masses showing positive immunoreactivity for CD117, DOG-1, CD34. Mutation analysis identified two mutations that located in the exon 13 of C-KIT and in the exon 18 of PDGFRA. The patient was treated sequentially with imatinib, sunitinib, sorafenib, and regorafenib. However, the prognosis was undesirable. Previous research has shown that expression of members of Bcl-2 family may be helpful in predicting prognosis, the survival time, and the resistance to chemotherapeutic agents. IHC was performed to detect the expression of BCL-2 family. The results show that high BCL-2 expression and low BAX expression in both specimens. In conclusion, our case may suggest that the presence of both C-KIT and PDGFRA mutations in EGISTs patients may indicate a very poor prognosis; and the expression level of BCL-2 and BAX could predict clinical outcome.

Primary prostatic extragastrointestinal stromal tumor: a case report and literature review

Objective

This study was performed to discuss the characteristics, diagnosis, and treatment of primary prostatic extragastrointestinal stromal tumor (EGIST).

Methods

The case history data of a patient with an EGIST were analyzed and discussed with a literature review.

Results

The patient was diagnosed with a pelvic tumor, possibly malignant. We ascertained the diagnosis by exploratory surgery and pathological biopsy. The tumor was present in the prostate and infiltrated and pressed against the anterior rectal wall. Pathological biopsy showed that the tumor comprised spindle cells, which were also present at the junction of the tumor and prostate tissue. Immunohistochemically, the tumor cells were positive for CD117, DOG-1, CD34, and smooth muscle actin and negative for S100 and desmin; Ki-67LI was about 10%. These results support the diagnosis of primary prostatic EGIST.

Conclusion

The rarity and nonspecific clinical manifestation of prostatic EGIST facilitate misdiagnosis. Diagnosis mainly depends on imaging examination and characteristic histopathological and immunohistochemical features, and GIST must be excluded. Surgery is the main treatment method, and imatinib is suggested for unresectable and malignant EGISTs.

Extragastrointestinal stromal tumors of the pelvic cavity and the vagina: Two case reports and review of the literature

Gastrointestinal stromal tumors (GISTs) are rare tumors of gastrointestinal (GI) tract with mesenchymal cell origin. Extragastrointestinal stromal tumors (EGISTs) are unusual tumors that exhibit the same immunohistochemical and genetic abnormalities as GISTs and most commonly affect the omentum and mesentery. EGISTs of the pelvis and the female reproductive system are exceedingly rare and a frequent diagnostic pitfall. In this report, we present two cases of EGISTs along with a review of the literature.

•

All pelvic and vaginal EGISTs summarized

•

Presentation of pelvic EGISTs is nonspecific leading to delay in diagnosis.

•

Surgery +/− imatinib potentially curative for vaginal and pelvic EGISTs.

•

C-kit testing is essential to differentiate EGISTs from other gynecological tumors.

Primary Prostatic Extragastrointestinal Stromal Tumor on 18F-FDG PET/CT

Extragastrointestinal stromal tumors are relatively rare soft tissue neoplasms originating from the extragastrointestinal tract. The present study reports an extremely rare case of primary gastrointestinal stromal tumor arising from the prostate. The final diagnosis was based on F-FDG PET/CT, enteroscopy, pathologic results, and immunohistochemical findings.