Indian Journal of Pathology and Microbiology

CASE REPORT
Year
: 2011  |  Volume : 54  |  Issue : 2  |  Page : 362--364

Gastrointestinal stromal tumor with skeletal muscle, adrenal and cardiac metastases: An unusual occurrence


Usman Bashir1, Asim Qureshi2, Haseeb A Khan2, Najam Uddin1,  
1 Department of Radiology, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
2 Department of Pathology, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan

Correspondence Address:
Asim Qureshi
Department of Pathology, Shaukat Khanum Memorial Cancer Hospital and Research Centre, 7-A Block R-3, M.A. Johar Town, Lahore
Pakistan

Abstract

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the bowel. It most commonly arises in the stomach, followed by the small intestine, colorectum and the esophagus. It usually spreads to the liver or the peritoneum, with bone and lung metastases being infrequent. Here, we present a case report of GIST behaving in a bizarre way. The patient presented with skeletal muscle metastasis and was initially misdiagnosed as leiomyosarcoma. On follow-up, he developed adrenal metastasis, and later, cardiac metastasis. None of the above unusual sites has previously been reported in literature to our knowledge.



How to cite this article:
Bashir U, Qureshi A, Khan HA, Uddin N. Gastrointestinal stromal tumor with skeletal muscle, adrenal and cardiac metastases: An unusual occurrence.Indian J Pathol Microbiol 2011;54:362-364


How to cite this URL:
Bashir U, Qureshi A, Khan HA, Uddin N. Gastrointestinal stromal tumor with skeletal muscle, adrenal and cardiac metastases: An unusual occurrence. Indian J Pathol Microbiol [serial online] 2011 [cited 2020 Aug 9 ];54:362-364
Available from: http://www.ijpmonline.org/text.asp?2011/54/2/362/81638


Full Text

 Introduction



Gastrointestinal stromal tumors (GISTs) represent the most common mesenchymal tumors of the gastrointestinal (GI) tract and were considered as leiomyomas in the past. [1] The identification of C-KIT (CD 117), a tyrosine kinase receptor, has led to the identification of a separate entity. GISTs most commonly arise in the wall of stomach and frequently spread to the liver and peritoneum. We report a case of GIST in whom the disease manifested a peculiar, previously undocumented metastatic pattern. We believe that this is the first report of its kind as spread to the adrenals or the heart has not been reported so fa r. Additional possible ways in which GIST may behave should be considered.

 Case Report



A 56-year-old man was referred to our tertiary care center for further management of leiomyosarcoma of upper back skeletal muscle. Review of submitted slides supported the diagnosis. Specific immune staining for GIST was not done at that time. While on follow-up, the patient presented to the emergency department with a diagnosis of subacute intestinal obstruction. Barium meal studies were requested which showed partial obstruction within the proximal jejunum. The rest of the small bowel and stomach were unremarkable.

A computerized tomography (CT) scan performed consequently showed jejuno-jejunal intussusception with the culprit mass visible in the intussuscipiens. In addition, the right adrenal appeared suspicious for metastasis [Figure 1]a and b.{Figure 1}

Histopathologic Findings

The patient underwent laparotomy with resection of jejunal and adrenal masses. Histopathology revealed high-grade spindle cell neoplasm with moderate to severe nuclear pleomorphism, brisk mitotic activity with occasional cells showing prominent nucleoli. There was focal evidence of necrosis as well. The c-kit (CD 117) and actin immunohistochemical stains were performed which were positive in tumor cells in both jejunal and adrenal masses [Figure 2]a and b. Based on these findings, a diagnosis of malignant (high-risk) GIST was made. Because the histological appearance was similar to the tumor initially excised from back, c-kit was also performed on the old blocks which again showed positive staining in the tumor cells.{Figure 2}

Having confirmed the diagnosis of GIST, the patient was started on imatinib and put on 6-monthly CT surveillance.

Development of Cardiac Metastasis

A year later, S4 gallop rhythm was noted on routine examination. Echocardiography revealed a mass inside the right atrium. The patient underwent open heart surgery with removal of the mass. Histopathology confirmed GIST metastasis [Figure 2]c and d. The dose of imatinib was raised to 800 mg daily considering progression of disease and the patient was scheduled for outpatient department follow-up.

 Discussion



GISTs are the most common mesenchymal tumors of the GI tract. Composed of non-epithelial cellular elements, these tumors are believed to arise from pacemaker interstitial cells of Cajal and are classically described as well-circumscribed exophytic masses arising from the subserosal surface of the GI tract. [1] In order of decreasing frequency, they occur in stomach (60-70%), the small intestine (20-30%), the colorectum (10%), and the esophagus (<5%). [2],[3]

As frequently quoted, these tumors were misdiagnosed as leiomyomas and leiomyosarcomas. Currently, positive immunohistochemical staining for KIT (CD 117; a tyrosine kinase receptor) is the histopathologic hallmark that differentiates them from the aforementioned tumors. [1],[4]

GISTs most frequently metastasize to the liver and peritoneum, with bone and lung metastases being uncommon sites. To our knowledge, GIST has not been known previously to spread to the skeletal muscle, cardiac muscle or adrenal. In retrospect, it seems probable that the jejunal mass resected after the initial skeletal mass may have been the primary which spread to involve the skeletal muscle, cardiac muscle and adrenal. The initial misdiagnosis as leiomyosarcoma was also because GIST has yet been unheard of metastasizing to skeletal muscle.

References

1Claudia M, Giulio R, Federica B, Riccardo V, Claudia C, Ivan R, et al. Incidence and clinicopathologic features of gastrointestinal stromal tumors: A population-based study. BMC Cancer 2007;7:230.
2Seiji S, Koji S, Masayuki M, Hidehiro W, Tadashi Y, Hiroshi M, et al. Pathologic complete response confirmed by surgical resection for liver metastases of gastrointestinal stromal tumor after treatment with imatinib mesylate. World J Gastroenterol 2008;14:3763-7.
3Brett H, Desmond Y, David G, Paul W, Victoria B, Guan C. Cerebral relapse of metastatic gastrointestinal stromal tumor during treatment with imatinib mesylate: Case report. BMC Cancer 2004;4:74.
4Martin EB, Jean-Yves B, Christopher C, Driman DK, Robert R, Denis S, et al. Gastrointestinal stromal tumours: Consensus statement on diagnosis and treatment. Can J Gastroenterol 2006;20:157-64.