Introduction

The study aimed to describe the brain metastases (BM) incidence, at diagnosis and follow-up, in patients initially presenting with stage III or IV melanoma and characterize their metastatic brain lesions. We also sought to describe the association of common genetic mutations and immunotherapy with BM development in advanced melanoma.

Methods

Using our institution’s tumor registry, we identified patients with initial diagnoses of stage III and stage IV melanoma. In this cohort, we obtained BM incidence at diagnosis and follow-up, characterized the metastatic brain lesions and primary tumor’s genetic profile.

Results

During the follow-up period, 22.9% of patients with an initial diagnosis of stage III developed BM. In this cohort, the median time for BM occurrence was 20 months; [95% CI (14–29)]. Likewise, 37.7% of patients with Stage IV melanoma presented with BM at the time of diagnosis, and 22.7% of remaining patients developed BM at follow-up over a median duration of 6 months [95% CI (4–11)]. Therefore, suggesting an overall incidence of 51.9% in stage IV melanoma. Next, we observed that the incidence of BM development during the follow-up period significantly decreased from 2012 to 2017 (p < 0.001). Lastly, we found a significantly higher frequency of mutational BRAF in the primary tumor of patients with BM (68.7% vs. 31.2%; p = 0.02).

Conclusions

While the overall incidence of BM remains high, the decreasing incidence of BM over the follow-up period is promising. Similar BM incidence in patients with an initial diagnosis of stage III or stage IV warrants appropriate imaging surveillance regimen for stage III patients.

中文翻译：

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III 期和 IV 期黑色素瘤转移性颅内病变的发生率和特征：单一机构回顾性分析

介绍

该研究旨在描述最初出现 III 期或 IV 期黑色素瘤的患者在诊断和随访时的脑转移 (BM) 发生率，并描述其转移性脑损伤的特征。我们还试图描述常见基因突变和免疫治疗与晚期黑色素瘤 BM 发展的关联。

方法

使用我们机构的肿瘤登记，我们确定了初步诊断为 III 期和 IV 期黑色素瘤的患者。在这个队列中，我们在诊断和随访时获得了 BM 发生率，表征了转移性脑损伤和原发性肿瘤的遗传特征。

结果

在随访期间，最初诊断为 III 期的患者中有 22.9% 发展为 BM。在该队列中，BM 发生的中位时间为 20 个月；[95% CI (14-29)]。同样，37.7% 的 IV 期黑色素瘤患者在诊断时出现 BM，其余 22.7% 的患者在中位 6 个月的随访中出现 BM [95% CI (4-11)]。因此，提示 IV 期黑色素瘤的总发病率为 51.9%。接下来，我们观察到从 2012 年到 2017 年，随访期间 BM 发展的发生率显着下降（p < 0.001）。最后，我们发现 BM 患者的原发性肿瘤中突变 BRAF 的频率明显更高（68.7% 对 31.2%；p = 0.02）。

结论

虽然 BM 的总体发病率仍然很高，但在随访期间 BM 发病率的下降是有希望的。在初步诊断为 III 期或 IV 期的患者中，类似的 BM 发生率需要对 III 期患者进行适当的影像学监测方案。