Department of Radiology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi 467-8601, Japan.
Narita Memorial Proton Center, 78 Shirakawa-cho, Toyohashi, Aichi 441-8021, Japan.
J Radiat Res. 2021 Jul 10;62(4):676-681. doi: 10.1093/jrr/rrab046.
Pleural dissemination is a common pattern of failure after initial treatment of thymoma and thymic carcinoma, but there is no standardized treatment. As these tumors are relatively radiosensitive, we investigated the effectiveness of radiotherapy. Twenty patients underwent 33 series of local radiotherapy for 96 pleural dissemination lesions after initial treatment. Conventional radiotherapy (CRT), tomotherapy, and combination of the two were employed in 19, 13, and 1 series, respectively. The median follow-up period after the first irradiation for pleural dissemination was 46 months (range, 14-161). For all 20 patients, overall survival (OS) rates from initial radiotherapy for pleural dissemination were 100% at three years and 86% at five years. Progression-free survival (PFS) rates after 33 series of radiotherapy were 30% at three years and 16% at five years. Local control (LC) rates for 96 lesions were 98% at three years and 96% at five years. In-field recurrence was observed in only two among the 96 lesions. One patient (5%) developed grade 3 radiation pneumonitis and another (5%) developed grade 3 pericardial effusion. No other serious adverse events were observed. When disseminated nodules can be covered within localized fields, local radiotherapy may be a treatment option. Using tomotherapy, multiple lesions can be treated safely.
胸膜播散是胸腺瘤和胸腺癌初始治疗后常见的失败模式，但尚无标准化治疗方法。由于这些肿瘤对放射治疗相对敏感，我们研究了放射治疗的效果。20 名患者在初始治疗后接受了 33 次局部放疗，共治疗了 96 处胸膜播散病变。分别有 19、13 和 1 例患者采用常规放疗（CRT）、调强放疗（tomotherapy）和两种方法的联合治疗。首次针对胸膜播散进行放疗后，中位随访时间为 46 个月（范围为 14-161 个月）。对于所有 20 名患者，胸膜播散初始放疗的总生存率（OS）在 3 年时为 100%，在 5 年时为 86%。33 次放疗后，无进展生存率（PFS）在 3 年时为 30%，在 5 年时为 16%。96 处病变的局部控制率（LC）在 3 年时为 98%，在 5 年时为 96%。96 处病变中仅 2 处出现了场内复发。1 名患者（5%）发生 3 级放射性肺炎，另 1 名患者（5%）发生 3 级心包积液。未观察到其他严重不良事件。当播散结节可以局限于局部区域时，局部放疗可能是一种治疗选择。使用调强放疗，可以安全地治疗多个病变。
