Princess Máxima Center for Pediatric Oncology, Utrecht, the Netherlands.
Princess Máxima Center for Pediatric Oncology, Utrecht, the Netherlands.
Eur J Surg Oncol. 2022 Jul;48(7):1536-1542. doi: 10.1016/j.ejso.2022.03.001. Epub 2022 Mar 12.
In-transit metastases (ITM) are defined as metastatic lymph nodes or deposits occurring between the primary tumor and proximal draining lymph node basin. In extremity rhabdomyosarcoma (RMS), they have rarely been reported. This study evaluates the frequency, staging and survival of patients with ITM in distal extremity RMS.
Patients with extremity RMS distal to the elbow or knee, enrolled in the EpSSG RMS 2005 trial between 2005 and 2016 were eligible for this study.
One hundred and nine distal extremity RMS patients, with a median age of 6.2 years (range 0-21 years) were included. Thirty seven of 109 (34%) had lymph node metastases at diagnosis, 19 of them (51%) had ITM, especially in lower extremity RMS. F-FDG-PET/CT detected involved lymph nodes in 47% of patients. In patients not undergoing F-FDG-PET/CT lymph node involvement was detected in 22%. The 5-yr EFS of patients with ITM vs proximal lymph nodes vs combined proximal and ITM was 88.9% vs 21.4% vs 20%, respectively (p = 0.01) and 5-yr OS was 100% vs 25.2% vs 15%, respectively (p = 0.003).
Our study showed that in-transit metastases constituted more than 50% of all lymph node metastases in distal extremity RMS. F-FDG-PET/CT improved nodal staging by detecting more regional and in-transit metastases. Popliteal and epitrochlear nodes should be considered as true (distal) regional nodes, instead of in-transit metastases. Biopsy of these nodes is recommended especially in distal extremity RMS of the lower limb. Patients with proximal (axillary or inguinal) lymph node involvement have a worse prognosis.
在途转移（ITM）被定义为原发肿瘤和近端引流淋巴结之间发生的转移性淋巴结或沉积物。在肢体横纹肌肉瘤（RMS）中，很少有报道。本研究评估了远端肢体 RMS 中 ITM 患者的频率、分期和生存情况。
符合条件的患者为 2005 年至 2016 年期间入组 EpSSG RMS 2005 试验的远端肘或膝关节以下的肢体 RMS 患者。
共纳入 109 例远端肢体 RMS 患者，中位年龄为 6.2 岁（范围 0-21 岁）。109 例患者中有 37 例（34%）诊断时存在淋巴结转移，其中 19 例（51%）有 ITM，尤其是在下肢 RMS 中。F-FDG-PET/CT 在 47%的患者中检测到受累淋巴结。在未行 F-FDG-PET/CT 的患者中，22%的患者检测到淋巴结受累。有 ITM 的患者与有近端淋巴结受累的患者相比，与有近端和 ITM 受累的患者相比，5 年 EFS 分别为 88.9%比 21.4%比 20%（p=0.01），5 年 OS 分别为 100%比 25.2%比 15%（p=0.003）。
我们的研究表明，在途转移在远端肢体 RMS 的所有淋巴结转移中占比超过 50%。F-FDG-PET/CT 通过检测更多的区域性和在途转移，提高了淋巴结分期。腘窝和外上髁淋巴结应被视为真正的（远端）区域淋巴结，而不是在途转移。建议对下肢远端肢体 RMS 进行这些淋巴结的活检。有近端（腋窝或腹股沟）淋巴结受累的患者预后较差。
