Long-Term Survival After Multidisciplinary Treatment Including Surgery for Metachronous Metastases of Small Intestinal Gastrointestinal Stromal Tumors after Curative Resection: A Case Report.

BACKGROUND Currently, 3 molecular targeted drugs are available for the treatment of unresectable and recurrent gastrointestinal stromal tumors (GISTs), and result in improved prognoses and rare occurrence of bone metastases. However, there is no established treatment guideline for bone metastases of GIST. CASE REPORT The patient was a 56-year-old male who was diagnosed with leiomyosarcoma in 1997. Partial resection of the small bowel was performed. As part of post-operative follow-up in 2004, a computed tomography scan showed metastatic lesions in the liver and the right femoral neck. Accordingly, partial hepatectomy was performed, followed by artificial femoral head replacement. In 2006, bone metastases were detected in the sternum, cervical and thoracic vertebra, and the right upper arm; therefore, the patient was subjected to radiotherapy. However, further histopathological examination revealed positive findings for CD34+ and KIT cells, prompting a diagnosis of GIST. Imatinib was started. The disease remained stable. However, in 2010, metastasis to the right ilium was detected, after which there was an increase in metastatic lesions in the thoracic vertebra, prompting a diagnosis of progressive disease. Thus, treatment with sunitinib was initiated. In 2012, the patient experienced spinal paralysis due to metastasis in the eighth thoracic vertebra. In 2013, metastases in the right ilium, lungs, and liver were detected. In 2014, the patient died. CONCLUSIONS Multidisciplinary treatment via radiotherapy and surgery for GIST with bone metastases indicates the possibility of extending the overall survival further.