ABSTRACT
Insulin-like growth factor II messenger RNA-binding protein 3 (IMP3) is a recently identified biomarker demonstrated to be useful in diagnosis and prognostic prediction for several kinds of malignant tumors. However, the clinicopathologic and diagnostic value of IMP3 in mesenchymal tumors of the gastrointestinal tract is not clear. In this study, we examined the immunohistochemical expression of IMP3 in gastrointestinal stromal tumor (GIST) (n = 150), malignant melanoma (n = 17), malignant mesothelioma (n = 6), leiomyosarcoma (n = 6), inflammatory myofibroblastic tumor (IMT) (n = 12), desmoid fibromatosis (n = 8), leiomyoma (n = 20), and schwannoma (n = 20). Focal (≥10%) or diffuse (≥50%) expression with strong staining for IMP3 was judged as positive. We found that malignant melanomas (16/17 cases, 94.1%), malignant mesotheliomas (5/6 cases, 83.3%), IMTs (7/12 cases, 58.3%), and leiomyosarcomas (2/6 cases, 33.3%) were positive for IMP3. Among IMTs and leiomyosarcomas, IMP3-positive cases were histologically and/or clinically aggressive subtypes. Other kinds of tumors, including GIST, desmoid fibromatosis, leiomyoma and schwannoma, were essentially negative for IMP3. Our results suggest that IMP3 may be an ancillary tool in identifying aggressive abdominal mesenchymal tumors other than GIST.
Subject(s)
Biomarkers, Tumor/metabolism , Gastrointestinal Neoplasms/diagnosis , Gastrointestinal Stromal Tumors/diagnosis , RNA-Binding Proteins/metabolism , Diagnosis, Differential , Gastrointestinal Neoplasms/metabolism , Gastrointestinal Neoplasms/pathology , Gastrointestinal Stromal Tumors/metabolism , Gastrointestinal Stromal Tumors/pathology , Humans , Leiomyoma/diagnosis , Leiomyoma/metabolism , Leiomyoma/pathology , Leiomyosarcoma/diagnosis , Leiomyosarcoma/metabolism , Leiomyosarcoma/pathology , Lung Neoplasms/diagnosis , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Melanoma/diagnosis , Melanoma/metabolism , Melanoma/pathology , Mesothelioma/diagnosis , Mesothelioma/metabolism , Mesothelioma/pathology , Mesothelioma, Malignant , Neurilemmoma/diagnosis , Neurilemmoma/metabolism , Neurilemmoma/pathology , PrognosisABSTRACT
Mutations of the epidermal growth factor receptor (EGFR) gene play a critical role in carcinogenesis of lung cancer, particularly adenocarcinoma. However, to the best of our knowledge, no mutations of the EGFR in patients with lung carcinosarcoma have been identified. We herein report the case of a 61-year-old female referred for a detailed examination of a left pulmonary mass shadow. Although bronchoscopy was performed, it failed to lead to a diagnosis, and video-assisted thoracoscopic surgery was therefore carried out to diagnose the tumor. The pathology revealed biphasic features consisting of both adenocarcinoma and chondrosarcoma. Intriguingly, both the adenocarcinoma and chondrosarcoma components were proven to harbor an exon19 deletion in the EGFR gene. Although carcinosarcoma is a rare malignancy of the lungs, genetic analyses of oncogenic drivers, such as the EGFR gene, should be conducted.
