Kim Bum Soo, Kim Seong-Jang, Pak Kyoungjune
Department of Nuclear Medicine, Pusan National University Hospital, 179 Gudeok-ro, Seo-gu, Busan, 602-739, Republic of Korea.
Biomedical Research Institute, Pusan National University Hospital, Busan, Republic of Korea.
Ann Nucl Med. 2016 Jun;30(5):346-54. doi: 10.1007/s12149-016-1068-9. Epub 2016 Feb 20.
Exact classifying between malignant and benign tumors in the parotid gland is important because the cancer has relatively poor prognosis. There have been several studies that F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) can differentiate between malignant and benign parotid gland tumors. However, the role of FDG PET is still controversial because many benign parotid gland tumors, such as Warthin's tumor and pleomorphic adenoma, show high FDG uptake. We hypothesized that metabolic heterogeneity would differentiate malignant parotid tumors because tumoral heterogeneity is an important characteristic in the malignancies.
From January 2010 to April 2015, we retrospectively reviewed the 46 patients who showed FDG uptake at the parotid gland. To differentiate malignant parotid gland tumors, we obtained maximum SUV and mean SUV. Metabolic tumor volume and total lesion glycolysis were measured as metabolic volumetric parameters. We also included heterogeneity parameters of FDG PET such as heterogeneity factor (HF) and the coefficient of variation for all patients.
There was significant difference of HF between malignant (-0.30 ± 0.25; range -0.937 to -0.084) and benign parotid gland tumors (-0.06 ± 0.05; range -0.291 to -0.012; p < 0.0001). In receiver operating characteristic analysis, when ≤-0.084 was used as the cut-off value for HF, the sensitivity and specificity were 100 % (95 % CI 81.5-100) and 89.2 % (95 % CI 71.8-97.7), respectively. HF showed the highest area under the curve of 0.947 among the parameters. In logistic regression analysis, the HF was the most powerful factor for differentiation of the parotid gland tumors (p = 0.002).
Our results suggest that HF can be utilized as a reliable and non-invasive method for differentiation of malignant and benign parotid gland tumors.
准确区分腮腺恶性肿瘤和良性肿瘤很重要，因为腮腺癌预后相对较差。已有多项研究表明，F-18氟脱氧葡萄糖（FDG）正电子发射断层扫描（PET）能够区分腮腺恶性肿瘤和良性肿瘤。然而，FDG PET的作用仍存在争议，因为许多腮腺良性肿瘤，如沃辛瘤和多形性腺瘤，也表现出较高的FDG摄取。我们推测代谢异质性可用于区分腮腺恶性肿瘤，因为肿瘤异质性是恶性肿瘤的一个重要特征。
回顾性分析2010年1月至2015年4月间46例腮腺出现FDG摄取的患者。为区分腮腺恶性肿瘤，我们获取了最大SUV和平均SUV。代谢肿瘤体积和总病变糖酵解作为代谢体积参数进行测量。我们还纳入了所有患者的FDG PET异质性参数，如异质性因子（HF）和变异系数。
恶性腮腺肿瘤（-0.30±0.25；范围-0.937至-0.084）与良性腮腺肿瘤（-0.06±0.05；范围-0.291至-0.012；p<0.0001）的HF存在显著差异。在受试者工作特征分析中，当HF的截断值≤-0.084时，敏感性和特异性分别为100%（95%CI 81.5-100）和89.2%（95%CI 71.8-97.7）。在所有参数中，HF的曲线下面积最高，为0.947。在逻辑回归分析中，HF是区分腮腺肿瘤的最有力因素（p=0.002）。
我们的结果表明，HF可作为一种可靠的非侵入性方法用于区分腮腺恶性肿瘤和良性肿瘤。
