Diagnostic Imaging Program, Molecular Imaging Center, National Institute of Radiological Sciences, Inage-ku, Chiba, Japan.
Ann Nucl Med. 2013 Jan;27(1):1-10. doi: 10.1007/s12149-012-0652-x. Epub 2012 Aug 23.
The purpose of this prospective study was to assess the prognostic value of 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) positron emission tomography/computed tomography (PET/CT) for the outcome of carbon ion radiotherapy (CIRT) in patients with mucosal malignant melanoma (MMM) of the head and neck.
Thirteen patients (69 ± 13 years) with histologically proven MMM tumor were enrolled. CIRT was performed with a total dose of 57.6-64.0 gray equivalents per 16 fractions over a period of 4 weeks. FLT-PET/CT was performed before and again 1 month after CIRT. Tumor FLT uptake was quantitatively assessed using the maximum standardized uptake value (SUV(max)). FLT-PET parameters [pre-CIRT SUV(max), post-CIRT SUV(max), and the reduction rate (RR)] and clinical parameters [age, gender, tumor site, tumor status, gross tumor volume (GTV), and regional lymph node involvement] were evaluated in relation to survival estimates. The follow-up period was 16.1 ± 5.9 months for 9 deceased patients, and 36.7 ± 7.9 months for 4 survivors.
Pre-CIRT SUV(max) of ≥4.3, age of ≥80 years old, sinonasal cavity tumor site, and GTV of ≥39 mL were found to be statistically significant prognostic factors for better overall survival. Pre-CIRT SUV(max) of ≥5.0, age of ≥80 years old, sinonasal cavity tumor site, and the absence of regional lymph node involvement were statistically significant prognostic factors for better metastasis-free survival. RR of ≥35 % and GTV of <73 mL were predictive of better local control.
The present study indicated for the first time that in patients with the head and neck MMM, FLT-PET/CT imaging was useful for predicting the therapeutic outcome of CIRT. Our results will contribute to the establishment of an effective staging system for MMM based on prognostic factors, depending on treatment choice.
本前瞻性研究旨在评估 3'-去氧-3'-[(18)F]氟代胸腺嘧啶（FLT）正电子发射断层扫描/计算机断层扫描（PET/CT）对碳离子放疗（CIRT）治疗头颈部黏膜恶性黑色素瘤（MMM）患者预后的预测价值。
本研究共纳入 13 例（69±13 岁）经组织学证实的 MMM 肿瘤患者。CIRT 采用总剂量 57.6-64.0 格雷当量，16 次分割，4 周完成。CIRT 前后 1 个月行 FLT-PET/CT。采用最大标准化摄取值（SUV(max))对肿瘤 FLT 摄取进行定量评估。FLT-PET 参数（CIRT 前 SUV(max)、CIRT 后 SUV(max)和减少率（RR)）和临床参数（年龄、性别、肿瘤部位、肿瘤状态、大体肿瘤体积（GTV)和区域淋巴结受累）与生存估计相关。9 例死亡患者的随访时间为 16.1±5.9 个月，4 例存活患者的随访时间为 36.7±7.9 个月。
CIRT 前 SUV(max)≥4.3、年龄≥80 岁、鼻腔鼻窦肿瘤部位和 GTV≥39mL 是总生存的统计学显著预后因素。CIRT 前 SUV(max)≥5.0、年龄≥80 岁、鼻腔鼻窦肿瘤部位和无区域淋巴结受累是无转移生存的统计学显著预后因素。RR≥35%和 GTV<73mL 是局部控制的预测因素。
本研究首次表明，对头颈部 MMM 患者，FLT-PET/CT 成像有助于预测 CIRT 的治疗效果。我们的研究结果将有助于根据治疗选择建立基于预后因素的 MMM 有效分期系统。
