Department of Pathology, Ankara Numune Training and Research Hospital, Ankara, Turkey.
Balkan Med J. 2015 Jan;32(1):30-7. doi: 10.5152/balkanmedj.2015.15547. Epub 2015 Jan 1.
IMP3, a member of insulin-like growth factor II m RNA binding protein family, seems to be promising in the diagnosis of carcinomas of many organs as well as malignant melanomas and some sarcomas. It is postulated that it might be a marker of malignancy. The results of the few prior studies indicate that IMP3 has the potential to be useful in distinguishing benign and malignant tumors of thyroid.
We aimed to evaluate the immunohistochemical expression of IMP3 in non-neoplastic nodules and benign and malignant tumors of the thyroid.
Diagnostic accuracy study.
Overall, 92 thyroid lesions, including 22 nodular hyperplasia (NH), 14 follicular adenoma (FA), 9 follicular carcinoma (FC), 37 papillary carcinoma (PC) (15 follicular variant), 3 well differentiated carcinoma-not otherwise specified (WDC-NOS), 4 poorly differentiated carcinoma (PDC) and anaplastic carcinoma (AC) were included. Immunohistochemically, cytoplasmic expression of IMP3 was evaluated in terms of extent and intensity of the staining semi-quantitatively and an immunohistochemical score (IHS) was obtained for each case. A score higher than 2 was considered positive staining.
In contrast with previous studies, we observed positive staining in benign lesions, especially in benign tumors. For identifying malignant tumors, the sensitivity of IMP3 was 82.1%, specificity was 33.3%, positive predictive value (PPV) was 65.7% and negative predictive value (NPV) was 54.5%. In distinguishing neoplastic and hyperplastic lesions, the sensitivity was 50%, specificity was 15.7%, PPV was 15.7% and NPV was 50%. The IMP3 expression was similar for FA and well differentiated carcinomas (p=0.434), but there was a significant difference between hyperplastic nodules and FA (p=0.011).
Our data suggest that IMP3 is effective in discriminating hyperplastic and neoplastic lesions but not useful in differentiating benign tumors from malignant tumors.
IMP3 是胰岛素样生长因子 II mRNA 结合蛋白家族的成员，似乎在许多器官的癌、恶性黑色素瘤和一些肉瘤的诊断中很有前途。据推测，它可能是恶性肿瘤的标志物。少数先前研究的结果表明，IMP3 有可能用于区分甲状腺的良性和恶性肿瘤。
评估 IMP3 在甲状腺非肿瘤性结节和良性及恶性肿瘤中的免疫组化表达。
诊断准确性研究。
共纳入 92 例甲状腺病变，包括 22 例结节性增生（NH）、14 例滤泡性腺瘤（FA）、9 例滤泡癌（FC）、37 例甲状腺乳头状癌（PC）（15 例滤泡变体）、3 例分化良好的癌-非特指型（WDC-NOS）、4 例低分化癌（PDC）和间变性癌（AC）。免疫组化检测 IMP3 的细胞质表达，根据染色的程度和强度进行半定量评估，并获得每个病例的免疫组化评分（IHS）。评分高于 2 被认为是阳性染色。
与之前的研究不同，我们观察到良性病变，尤其是良性肿瘤存在阳性染色。对于识别恶性肿瘤，IMP3 的敏感性为 82.1%，特异性为 33.3%，阳性预测值（PPV）为 65.7%，阴性预测值（NPV）为 54.5%。在区分肿瘤性和增生性病变时，敏感性为 50%，特异性为 15.7%，PPV 为 15.7%，NPV 为 50%。FA 和分化良好的癌之间的 IMP3 表达相似（p=0.434），但增生性结节和 FA 之间有显著差异（p=0.011）。
我们的数据表明，IMP3 可有效区分增生性和肿瘤性病变，但不能用于区分良性肿瘤和恶性肿瘤。
