A case of gastrointestinal stromal tumor (GIST) presented. The patient was diagnosed and then treated with surgical excision of affected 20-cm part of small bowel with polips growing into peritoneal cavity.
The slides represent fine-needle biopsy stained with HE, cell-block stained with HE, cell-block with immunohistochemical staining, and histopatological specimen of surgically excised tissue stained with HE respectively.
Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors characterized by expression of the c-kit proto-oncogene. GISTs occur primarily in the stomach and small intestine, they occur less often in large intestine, and rarely in esophagus, but sometimes GISTs are multicentric. These tumors present themselves with abdominal pain or bleeding, but may be found incidentally. And they may behave malignantly by metastasizing, invading adjacent organs, or recurring after resection.
Cytologically, GISTs may appear as spindle cells that are characterized by nuclear palisading or prominent perinuclear vacuolization pattern, or epithelioid ones that may have either a solid pattern or a myxoid pattern, with a possible compartmental pattern. Our case demonstrates spindle cell variant of GIST, where the diagnosis is confirmed by immunohistological staining.
Diagnosis of GIST can be established by evaluation of tissue biopsy or performed by experienced specialist fine needle aspiration biopsy with staining of the specimen for the c-kit protein (also known as CD-117) and CD-34. It is shown that approximately 90%-95% of GISTs are positive for c-kit and 50%-70% are positive for CD-34. Besides, GISTs are negative for desmin in 90%-95% - unlike leiomiomas or leiomyosarcomas.
The c-kit protein is recognized as a highly sensitive and specific marker for GISTs. This marker differentiates GISTs from other gastrointestinal tract neoplasms, including leiomyomas, leiomyosarcomas, schwannomas and neuroendocrine tumors - no of them express c-kit, though some other tumors and cells of Cajal do. The most useful signs of GIST malignancy are tumor size more than 5 cm or more than 5 mitoses per 10 high-power fields (HPF).
GIST in literature:
- Christopher L. Corless, Laura McGreevey, Andrea Haley, Ajia Town and Michael C. Heinrich: KIT Mutations Are Common in Incidental Gastrointestinal Stromal Tumors One Centimeter or Less in Size. Am J Pathol 160:1567-1572, 2002
- Deshpande A, Munshi MM: Gastrointestinal Stromal Tumours - Report of Three Cases and Review of Literature. J Cytol 24(2):96-100, 2007
- Ihor Pidhorecky, Richard T. Cheney, William G. Kraybill and John F. Gibbs: Gastrointestinal Stromal Tumors: Current Diagnosis, Biologic Behavior, and Management. Ann Surg Oncol 7(9):705-712, 2000
- J.-Y. Blay et al: Consensus meeting for the management of gastrointestinal stromal tumors - Report of the GIST Consensus Conference of 20-21 March 2004, under the auspices of ESMO. Ann Oncol 16(4):566-578, 2005
- Shunsuke Kondo, Umio Yamaguchi, Shinji Sakurai, Yoshisuke Ikezawa, Hirokazu Chuman, Ukihide Tateishi, Koh Furuta and Tadashi Hasegawa: Cytogenetic Confirmation of a Gastrointestinal Stromal Tumor and Ewing Sarcoma/Primitive Neuroectodermal Tumor in a Single Patient. Jpn J Clin Oncol 35(12):753-756, 2005
- Vu H Nguyen, Andrew Taylor: Gastrointestinal Stromal Tumors - Leiomyoma/Leiomyosarcoma. eMedicine Specialties, 2008
- Yoshihiro Sakamoto, Junji Yamamoto, Hidenori Takahashi, Norihiro Kokudo, Toshiharu Yamaguchi, Tetsuichiro Muto and Masatoshi Makuuchi: Segmental Resection of the Third Portion of the Duodenum for a Gastrointestinal Stromal Tumor: a Case Report. Jpn J Clin Oncol 33:364-366, 2003
Case prepared by:
Jacek Sygut, Janusz Kopczynski, Piotr Faszczewski, Roman Bastow,
Zaklad Patologii Nowotworow, Swietokrzyskie Centrum Onkologii.