PDF(Pubmed)
Abstract：
BACKGROUND: Merkel cell carcinoma (MCC) is often treated with surgery and postoperative radiation therapy (PORT). The optimal time to initiate PORT (Time-to-PORT [ttPORT]) is unknown.
OBJECTIVE: We assessed if delays in ttPORT were associated with inferior outcomes.
METHODS: Competing risk regression was used to evaluate associations between ttPORT and locoregional recurrence (LRR) for patients with stage I/II MCC in a prospective registry and adjust for covariates. Distant metastasis and death were competing risks.
RESULTS: The cohort included 124 patients with median ttPORT of 41 days (range: 8-125 days). Median follow-up was 55 months. 17 (14%) patients experienced a LRR, 14 (82%) of which arose outside the radiation field. LRR at 5 years was increased for ttPORT >8 weeks vs ≤ 8 weeks, 28.0% vs 9.2%, P = .006. There was an increase in the cumulative incidence of MCC-specific death with increasing ttPORT (HR = 1.14 per 1-week increase, P = .016).
CONCLUSIONS: The relatively low number of LRRs limited the extent of our multivariable analyses.
CONCLUSIONS: Delay of PORT was associated with increased LRR, usually beyond the radiation field. This is consistent with the tendency of MCC to spread quickly via lymphatics. Initiation of PORT within 8 weeks was associated with improved locoregional control and MCC-specific survival.
OBJECTIVE: We assessed if delays in ttPORT were associated with inferior outcomes.
METHODS: Competing risk regression was used to evaluate associations between ttPORT and locoregional recurrence (LRR) for patients with stage I/II MCC in a prospective registry and adjust for covariates. Distant metastasis and death were competing risks.
RESULTS: The cohort included 124 patients with median ttPORT of 41 days (range: 8-125 days). Median follow-up was 55 months. 17 (14%) patients experienced a LRR, 14 (82%) of which arose outside the radiation field. LRR at 5 years was increased for ttPORT >8 weeks vs ≤ 8 weeks, 28.0% vs 9.2%, P = .006. There was an increase in the cumulative incidence of MCC-specific death with increasing ttPORT (HR = 1.14 per 1-week increase, P = .016).
CONCLUSIONS: The relatively low number of LRRs limited the extent of our multivariable analyses.
CONCLUSIONS: Delay of PORT was associated with increased LRR, usually beyond the radiation field. This is consistent with the tendency of MCC to spread quickly via lymphatics. Initiation of PORT within 8 weeks was associated with improved locoregional control and MCC-specific survival.
摘要：
背景：默克尔细胞癌（MCC）通常采用手术和术后放射治疗（PORT）治疗。启动PORT(ttPORT)的最佳时间未知。
目的：我们评估了ttPORT延迟是否与不良结局相关。
方法：在前瞻性登记中，对于I/II期MCC患者，使用竞争风险回归评估ttPORT与局部复发（LRR）之间的关联，并调整协变量。远处转移和死亡是竞争风险。
结果：该队列包括124例患者，中位ttPORT为41天[范围：8-125天]。中位随访时间为55个月。17例(14%)患者经历了LRR，14(82%)其中出现在辐射场之外。5年时LRR在ttPORT>8周与<=8周之间增加，28.0%比9.2%，p=0.006。随着ttPORT的增加，MCC特异性死亡的累积发生率增加（HR=1.14每1周增加，p=0.016)。
结论：相对较低的LRR数量限制了我们多变量分析的范围。
结论：PORT延迟与LRR增加有关，通常超出辐射场。这与MCC通过淋巴管快速扩散的趋势一致。在8周内启动PORT与局部区域控制和MCC特异性生存率的改善有关。
目的：我们评估了ttPORT延迟是否与不良结局相关。
方法：在前瞻性登记中，对于I/II期MCC患者，使用竞争风险回归评估ttPORT与局部复发（LRR）之间的关联，并调整协变量。远处转移和死亡是竞争风险。
结果：该队列包括124例患者，中位ttPORT为41天[范围：8-125天]。中位随访时间为55个月。17例(14%)患者经历了LRR，14(82%)其中出现在辐射场之外。5年时LRR在ttPORT>8周与<=8周之间增加，28.0%比9.2%，p=0.006。随着ttPORT的增加，MCC特异性死亡的累积发生率增加（HR=1.14每1周增加，p=0.016)。
结论：相对较低的LRR数量限制了我们多变量分析的范围。
结论：PORT延迟与LRR增加有关，通常超出辐射场。这与MCC通过淋巴管快速扩散的趋势一致。在8周内启动PORT与局部区域控制和MCC特异性生存率的改善有关。
