Greven K M, Williams D W, Keyes J W, McGuirt W F, Watson N E, Case L D
Department of Radiation Oncology, Bowman Gray School of Medicine, Winston-Salem, North Carolina 27157, USA.
Cancer J Sci Am. 1997 Nov-Dec;3(6):353-7.
Distinguishing persistent or recurrent tumor from post-radiation edema or soft-tissue/cartilage necrosis in patients treated for carcinoma of the larynx can be difficult. Because recurrent tumor is often submucosal, multiple deep biopsies may be necessary before a diagnosis can be established. Positron emission tomography with F-18 fluorodeoxyglucose was studied for its ability to aid in this problem.
FDG PET scans were performed on 31 patients who were suspected of having persistent or recurrent tumor after radiation treatment for carcinoma of the larynx. Patients underwent thorough history and physical examinations, scans with computed tomography (23 patients), and pathological evaluation when indicated. PET scans were interpreted by each of the two radiologists, who were blinded to patient outcome and the other's report.
The time between completion of radiation treatment and positron emission tomography examination ranged from 2 to 61 months with a median of 6 months. Fifteen patients had pathological evidence of tumor in the larynx, while 16 have remained without evidence of disease. The overall sensitivity and specificity of the positron emission tomography interpretations were 80% and 81%, respectively. The sensitivity and specificity of the computed tomography scan interpretations were 58% and 100%, respectively. Of the 23 patients with computed tomography scans, eight patients acquired useful information from the positron emission tomography, three patients had incorrect positron emission tomography interpretations and correct computed tomography interpretations, and one patient had positive tumor despite a negative positron emission tomography and computed tomography.
Positron emission tomography is useful in distinguishing benign from malignant changes in the larynx after radiation treatment. This noninvasive technique can supplement information provided by computed tomography scans. It is reasonable to delay biopsy, which could traumatize radiation-damaged tissues and precipitate necrosis, for those patients with negative positron emission tomography scans who have clinical signs and symptoms associated with recurrence.
对于接受喉癌治疗的患者，区分持续性或复发性肿瘤与放疗后水肿或软组织/软骨坏死可能存在困难。由于复发性肿瘤常位于黏膜下，在确诊之前可能需要进行多次深部活检。本研究旨在探讨18F-氟脱氧葡萄糖正电子发射断层显像（FDG PET）在解决这一问题方面的能力。
对31例疑似喉癌放疗后存在持续性或复发性肿瘤的患者进行了FDG PET扫描。患者接受了全面的病史询问和体格检查，其中23例患者还进行了计算机断层扫描（CT），并在必要时进行了病理评估。两名放射科医生分别对PET扫描结果进行解读，他们均不知晓患者的预后情况及对方的报告。
放疗结束至进行正电子发射断层显像检查的时间间隔为2至61个月，中位时间为6个月。15例患者喉部有肿瘤的病理证据，16例患者无疾病证据。PET扫描解读的总体敏感性和特异性分别为80%和81%。CT扫描解读的敏感性和特异性分别为58%和100%。在23例进行CT扫描的患者中，8例患者从PET扫描中获得了有用信息，3例患者PET扫描解读错误但CT扫描解读正确，1例患者尽管PET扫描和CT扫描均为阴性，但肿瘤呈阳性。
正电子发射断层显像有助于区分喉癌放疗后的良性和恶性改变。这种非侵入性技术可补充CT扫描提供的信息。对于PET扫描阴性但有与复发相关临床症状和体征的患者，推迟活检是合理的，因为活检可能会损伤受辐射损伤的组织并引发坏死。
