Rostomily Robert C, Elias Maria, Deng Mei, Elias Paul, Born Donald E, Muballe David, Silbergeld Daniel L, Futran Neal, Weymuller Ernest A, Mankoff David A, Eary Janet
Department of Neurological Surgery, University of Washington School of Medicine, Mailstop 356470; Room RR-744, 1959 NE Pacific Street, Seattle, WA 98195, USA.
Head Neck. 2006 Apr;28(4):305-12. doi: 10.1002/hed.20356.
For tumors that express somatostatin receptors (SSTR), radiolabeled somatostatin analogs, such as 111In-pentetreotide, can demonstrate the presence of tumor by radioligand uptake using somatostatin receptor scintigraphy (SRS). The use of 111In-pentetreotide for SRS depends on the specific high affinity of octreotide for SSTR subtypes 2, 3, and 5. Of these, SSTR2 has the greatest affinity for octreotide and the greatest relevance for tumor detection with Octreoscan imaging. Discriminating between postoperative changes and residual or recurrent tumor after extensive skull base surgery is often difficult, but in a case of recurrent esthesioneuroblastoma (ENB) we found the use of Octreoscan imaging clinically useful. To better define the general relevance of this imaging technique in this setting, we analyzed SSTR subtype expression in a panel of ENB tumors.
The case history and correlations between MRI and 111In-pentetreotide SRS of a patient with recurrent ENB were reviewed. The expression pattern of the SSTR subtypes in a panel of ENB tumors was then analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) to better define the potential of more general use of Octreoscan for imaging ENB. To correlate SSTR2 protein expression with 111In-pentetreotide uptake, immunohistochemistry to detect SSTR2 was performed on tumor samples from regions of increased uptake on Octreoscan.
The SSTR2 message was expressed at high levels in all five ENB tumor samples, and either SSTR2 protein or histologic findings typical for ENB were found in all tumor tissue obtained from regions of increased 111In-pentetreotide uptake. Furthermore, Octreoscan imaging in this case proved useful in clinical decision making.
The expression pattern of SSTR2 and the specificity of the Octreoscan for regions of active tumor growth support further investigation of the utility of Octreoscan imaging in the diagnosis and surveillance of ENB. Recent advances in novel therapies based on SSTR ligand binding also provide the rationale to consider such novel therapeutic approaches in patients with ENB.
对于表达生长抑素受体（SSTR）的肿瘤，放射性标记的生长抑素类似物，如111In-喷曲肽，可通过生长抑素受体闪烁显像（SRS）利用放射性配体摄取来显示肿瘤的存在。111In-喷曲肽用于SRS取决于奥曲肽对SSTR亚型2、3和5的特异性高亲和力。其中，SSTR2对奥曲肽的亲和力最高，与奥曲肽扫描成像检测肿瘤的相关性最大。在广泛的颅底手术后，区分术后改变与残留或复发性肿瘤往往很困难，但在一例复发性嗅神经母细胞瘤（ENB）中，我们发现奥曲肽扫描成像在临床上很有用。为了更好地确定这种成像技术在这种情况下的普遍相关性，我们分析了一组ENB肿瘤中SSTR亚型的表达。
回顾了一例复发性ENB患者的病史以及MRI与111In-喷曲肽SRS之间的相关性。然后通过逆转录聚合酶链反应（RT-PCR）分析一组ENB肿瘤中SSTR亚型的表达模式，以更好地确定奥曲肽扫描在ENB成像中更广泛应用的潜力。为了将SSTR2蛋白表达与111In-喷曲肽摄取相关联，对奥曲肽扫描上摄取增加区域的肿瘤样本进行免疫组织化学检测SSTR2。
在所有五个ENB肿瘤样本中，SSTR2信息均高表达，并且在从111In-喷曲肽摄取增加区域获得的所有肿瘤组织中均发现了SSTR2蛋白或典型的ENB组织学表现。此外，该病例中的奥曲肽扫描成像在临床决策中被证明是有用的。
SSTR2的表达模式以及奥曲肽扫描对活跃肿瘤生长区域的特异性支持进一步研究奥曲肽扫描成像在ENB诊断和监测中的效用。基于SSTR配体结合的新型疗法的最新进展也为考虑在ENB患者中采用这种新型治疗方法提供了理论依据。
