Ribociclib-Letrozole Combination as an Alternative for Neoadjuvant Chemotherapy in Selected Postmenopausal Patients with Luminal Breast Cancer (BOOG 2017-01).

The NEOLBC trial studied whether neoadjuvant ribociclib plus letrozole (RL) results in a doubling of complete cell-cycle arrest (CCCA; Ki67 <1% on IHC) compared with CT in the surgical specimen in luminal breast cancer.

NEOLBC试验研究了在腔内型乳腺癌中，新辅助利匹替尼联合来曲唑（RL）是否能在手术标本中使细胞周期完全阻滞（CCCA；IHC上Ki67 <1%）的比率加倍，与化疗相比。

patients_and_methods

This randomized phase II trial tailored neoadjuvant therapy in postmenopausal patients with early, luminal, HER2-negative, stage II/III breast cancer based on the percentage of Ki67-positive cancer cells after 2 weeks of letrozole.

这项随机II期试验根据绝经后患者在使用来曲唑治疗2周后，肿瘤细胞中Ki67阳性比例的情况，为早期、腔内型、HER2阴性、II/III期乳腺癌患者定制了新辅助治疗方案。

Patients with a Ki67 ≥1% were randomized between RL and standard CT.

Ki67表达水平≥1%的患者在RL方案和标准化疗方案之间进行了随机分配。

Secondary endpoints included pathologic response and toxicity.

次要终点包括病理反应和毒性。

Results

Of 161 registered patients, 70 were randomized, and 66 started the allocated treatment.

在161名登记患者中，有70名被随机分配，66名开始了分配的治疗。

The CCCA in the surgical specimen was similar for both groups: 35.3% in the RL group and 31.3% in the CT group (P = 0.73).

手术标本中，两组的细胞减少率相似：RL组为35.3%，CT组为31.3%（P = 0.73）。

The response according to Miller and Payne was not significantly different between the two groups, nor was the pathologic complete response rate.

根据Miller和Payne的评估，两组的反应没有显著差异，病理完全缓解率也是如此。

Overall toxicity was observed more often in the CT group.

在CT组中，总体毒性发生得更频繁。

In the RL group, eight patients discontinued treatment due to toxicity, and in the CT group, 10 patients discontinued treatment.

在RL组中，有八名患者因毒性而停药，在CT组中，有10名患者因毒性而停药。

Conclusions

Although the primary endpoint was not met, the NEOLBC trial (NCT03283384) showed a similar CCCA and pathologic response for RL and CT with less toxicity.

尽管主要终点未达成，NEOLBC试验（NCT03283384）显示RL和CT在CCCA和病理反应方面相似，但RL的毒性较低。

Therefore, RL as an alternative to neoadjuvant CT merits further investigation.

因此，作为新辅助化疗的替代方案，RL值得进一步研究。