Cytological Findings of Gastrointestinal Stromal Tumor-Derived Bone Metastasis

Abstract

Objective: Procedures for diagnosing bone tumors should be rapid and minimally invasive. Thus, cytological examinations are more useful for such purposes than histological examinations. In order to identify cytomorphological findings that could be used to diagnose bone metastasis from gastrointestinal stromal tumors (GIST), previous cases were reviewed. Study Design: Cytological samples of 7 lesions from 4 patients with GIST-derived bone metastasis, which were obtained from 2001 to 2017 at the JFCR Cancer Institute Hospital, were reviewed. Results: The metastasis of GIST to the bone was clinically suspected before the cytological and histological examinations in all cases since they all involved other metastatic lesion(s), and characteristic osteolytic lesions were detected on radiological images. Although various cell shapes were encountered, spindle cell proliferation was seen in all cytological samples. No pleomorphism was apparent. Characteristic nuclear findings were observed. All of the cases could be diagnosed as GIST-derived bone metastasis. Conclusion: GIST-derived bone metastasis can be diagnosed by examining cytological samples.

<p>Bone Metastases of Gastrointestinal Stromal Tumor: A Review of Published Literature</p>

“…Regarding the primary locations of GIST, 14 cases were from the stomach and small intestine, respectively (31.11%), 11 cases were from the colorectal (24.44%), 2 cases were from the esophagus (4.44%), 2 cases were of unknown origination (4.44%), and 1 case was from the ovary and liver, respectively (2.22%). Bone metastases mainly occurred in the spine (21), followed by the rib (15), femur (8), humerus (8), pelvis (8) and other bones.…”

“…In a recent study of GIST metastases, the incidence of bone metastases in GIST was limited to only 0.47%, 9 much less than that in previous reports of 3.2-6%. 2,15 Not unexpectedly, GIST metastasis to the bone may become more prevalent due to extensive use of imaging techniques and increased patient life expectancy resulting from the improvement in therapeutic modalities. Nevertheless, only 45 cases of bone metastases were included in this study after searching the whole database.…”

“…Usually, metastasis of GIST occurs in the abdominal cavity, while bone involvement is rather rare. 15,16 It is of great importance to recognize bone metastases of GIST since they may subsequently develop skeleton-related events associated with severe results. As there are only single case reports or small series focusing on bone metastasis of GIST, the clinicopathological characteristics of these tumors and their metastases have not yet been well characterized.…”