Lindholm P, Leskinen-Kallio S, Grénman R, Lehikoinen P, Någren K, Teräs M, Ruotsalainen U, Joensuu H
Department of Oncology and Radiotherapy, Turku University Cyclotron/PET Center, Finland.
Int J Radiat Oncol Biol Phys. 1995 Jun 15;32(3):787-94. doi: 10.1016/0360-3016(95)00007-L.
To evaluate the usefulness of positron emission tomography (PET) and L-[methyl-11C]methionine in assessing treatment response to radiotherapy in head and neck cancer.
Fifteen patients with head and neck cancer (13 with squamous cell carcinoma, 1 with adenocystic carcinoma, and 1 with paranasal plasmocytoma) underwent a PET study with [11C]-methionine both before and after preoperative radiotherapy to the total tumor dose of 61-73 Gy. Twelve primary and 12 metastatic tumor sites were within the field of view. Nineteen of the 24 tumor sites were surgically explored after radiotherapy, and the tumor standardized uptake values (SUVs) of [11C]methionine were compared with histological findings.
All 24 malignant lesions were detectable in the pretreatment study. In all but one case, the tumor SUV decreased after radiotherapy. The median SUV of the tumor site was smaller (1.9, range, 1.3-3.1, n = 7) in cases with histologically verified complete response than in cases with persistent cancer (median 4.1, range, 2.8-7.6, n = 12, p = 0.0008). A complete histological response was verified in none of the 9 cases with a postirradiation SUV larger than the median (3.1), whereas 7 of the 10 cases with a SUV of 3.1 or smaller had complete response (p = 0.003). The preirradiation uptake of [11C]methionine in tumors did not have significant association with histological response (p = 0.45). The PET findings correlated well with follow-up data in five cases with unoperated tumor sites. The [11C]methionine uptake of the submandibular salivary glands decreased after radiotherapy (p = 0.04).
PET with [11C]methionine as a tracer may be useful in assessing response to radiotherapy in head and neck cancer. High uptake of [11C]methionine in the postirradiation scan suggests the presence of persistent disease.
评估正电子发射断层扫描（PET）及L-[甲基-11C]蛋氨酸在评估头颈部癌放疗治疗反应中的作用。
15名头颈部癌患者（13例鳞状细胞癌、1例腺囊性癌和1例鼻旁浆细胞瘤）在术前放疗至总肿瘤剂量61 - 73 Gy前后均接受了[11C] - 蛋氨酸PET检查。视野内有12个原发肿瘤部位和12个转移肿瘤部位。放疗后对24个肿瘤部位中的19个进行了手术探查，并将[11C]蛋氨酸的肿瘤标准化摄取值（SUV）与组织学结果进行比较。
在预处理研究中所有24个恶性病变均能被检测到。除1例之外，所有病例放疗后肿瘤SUV均下降。组织学证实为完全缓解的病例中肿瘤部位的SUV中位数较小（1.9，范围1.3 - 3.1，n = 7），低于持续存在癌症的病例（中位数4.1，范围2.8 - 7.6，n = 12，p = 0.0008）。放疗后SUV大于中位数（3.1）的9例病例中无一例组织学证实为完全缓解，而SUV为3.1或更小的10例病例中有7例为完全缓解（p = 0.003）。肿瘤术前[11C]蛋氨酸摄取与组织学反应无显著相关性（p = 0.45）。PET结果与5例未手术肿瘤部位的随访数据相关性良好。放疗后下颌下唾液腺的[11C]蛋氨酸摄取下降（p = 0.04）。
以[11C]蛋氨酸为示踪剂的PET可能有助于评估头颈部癌的放疗反应。放疗后扫描中[11C]蛋氨酸摄取高提示存在持续性疾病。
