Cuenin M, Levy A, Peiffert D, Sunyach M P, Ducassou A, Cordoba A, Gillon P, Thibouw D, Lapeyre M, Lerouge D, Helfre S, Leroux A, Salleron J, Sirveaux F, Marchal F, Debordes P A
Department of Radiation Oncology, Institut de Cancérologie de Lorraine, Vandœuvre-lès-Nancy, France.
Department of Radiation Oncology, Gustave Roussy, Thoracic Oncology Institute (IOT), Villejuif, France.
Clin Transl Radiat Oncol. 2024 Jul 26;48:100825. doi: 10.1016/j.ctro.2024.100825. eCollection 2024 Sep.
To retrospectively identify clinical, pathologic, or imaging factors predictive of local relapse (LR) after preoperative radiotherapy (RT) for soft tissue sarcomas (STS).
This is a retrospective multicenter study of patients who underwent preoperative RT and surgery for limb or trunk wall STS between 2007 and 2018 in French Sarcoma Group centers and were enrolled in the "Conticabase". Patterns of LR were investigated taking into account the multimodal response after preoperative RT. Diagnostic and surgical samples were compared after systematic review by expert pathologists and patients were stratified by tumor grade. Log-rank tests and Cox models were used to identify prognostic factors for radiation response and LR.
257 patients were included; 17 % had low-grade (LG), 72.5 % had high-grade (HG) sarcomas. In HG group, tumors were larger, mostly undifferentiated, and displayed more necrosis and perilesional edema after RT. Median follow-up was 32 months. Five-year cumulative incidence of LR was 20.3 % in the HG group versus 9.7 % in the LG group (p = 0.026). In multivariate analysis, trunk wall location (HR 6.79, p = 0.012) and proportion of viable tumor cellularity ≥ 20 % (HR 3.15, p = 0.018) were associated with LR. After adjusting for tumor location, combination of histotype and cellularity rate significantly correlated with LR. We described three prognostic subgroups for HG sarcomas, listed from the highest to lowest risk: undifferentiated sarcoma (US) with cellularity rates ≥ 20 %; non-US (NUS) with cellularity rates ≥ 20 % or US with cellularity rates < 20 %; and NUS with cellularity rates < 20 %, which shared similar prognostic risks with LG sarcomas.
HG and LG tumors have different morphological and biological behaviors in response to RT. Combination of cellularity rate with histotype could be a major prognostic for LR. Patients with undifferentiated HG sarcomas with cellularity rates ≥ 20 % after preoperative RT had the highest risk of LR and disease-specific death.
回顾性确定软组织肉瘤（STS）术前放疗（RT）后局部复发（LR）的临床、病理或影像预测因素。
这是一项回顾性多中心研究，研究对象为2007年至2018年期间在法国肉瘤研究组中心接受肢体或躯干壁STS术前放疗和手术并纳入“Conticabase”的患者。考虑术前放疗后的多模式反应，对LR模式进行研究。在专家病理学家进行系统评估后，对诊断和手术样本进行比较，并根据肿瘤分级对患者进行分层。采用对数秩检验和Cox模型确定放疗反应和LR的预后因素。
纳入257例患者；17%为低级别（LG）肉瘤，72.5%为高级别（HG）肉瘤。在HG组中，肿瘤更大，大多为未分化型，放疗后坏死和瘤周水肿更明显。中位随访时间为32个月。HG组LR的5年累积发生率为20.3%，而LG组为9.7%（p = 0.026）。多因素分析显示，躯干壁部位（HR 6.79，p = 0.012）和存活肿瘤细胞比例≥20%（HR 3.15，p = 0.018）与LR相关。在调整肿瘤部位后，组织学类型和细胞比例的组合与LR显著相关。我们描述了HG肉瘤的三个预后亚组，从最高风险到最低风险依次为：细胞比例≥20%的未分化肉瘤（US）；细胞比例≥20%的非未分化肉瘤（NUS）或细胞比例<20%的US；以及细胞比例<20%的NUS，其预后风险与LG肉瘤相似。
HG和LG肿瘤对放疗的形态学和生物学行为不同。细胞比例与组织学类型的组合可能是LR的主要预后因素。术前放疗后细胞比例≥20%的未分化HG肉瘤患者LR和疾病特异性死亡风险最高。
