Background

Amelanotic malignant melanoma (AMM) is challenging to diagnose. Clinical risk factors for AMM are not well defined.

Objective

To investigate clinicopathologic, misdiagnosis, and survival differences between patients with AMM and those with pigmented malignant melanoma (PMM).

Methods

A cross-sectional retrospective medical record review at a tertiary academic medical center.

Results

A total of 933 patients with melanoma with known presenting tumor color were identified (342 with AMM vs 591 with PMM). AMM was associated with older age, history of nonmelanoma skin cancer, and red hair, whereas AMM was inversely associated with a family history of melanoma, more than 50 nevi, and a history of dysplastic nevi. Compared with PMM, AMM was more likely to be located on the head and/or neck, had more aggressive pathologic features (greater Breslow depth and/or mitoses, ulceration, nodular subtype), and was less likely to be associated with a precursor nevus or regression. Finally, patients with AMM were more likely to be misdiagnosed than were patients with PMM (25% vs 12% clinically and 12% vs 7% pathologically), and they had poorer melanoma-specific survival (5-year overall survival rate, 0.77 [95% confidence interval, 0.72-0.82] vs 0.84 [95% confidence interval, 0.80-0.87]).

Limitations

Retrospective study design, single-institutional study.

Conclusion

Greater clinician awareness, lower biopsy thresholds, and increased patient education may be useful to enhance AMM detection in patients with certain characteristics.

中文翻译：

---

临床无色素性黑色素瘤和色素性黑色素瘤之间的临床病理、误诊和生存差异

背景

无色素性恶性黑色素瘤 (AMM) 的诊断具有挑战性。AMM 的临床危险因素尚未明确定义。

客观的

研究 AMM 患者与色素性恶性黑色素瘤 (PMM) 患者的临床病理、误诊和生存差异。

方法

在三级学术医疗中心进行的横断面回顾性病历审查。

结果

共鉴定出 933 名具有已知肿瘤颜色的黑色素瘤患者（342 名患有 AMM，591 名患有 PMM）。AMM 与高龄、非黑色素瘤皮肤癌病史和红头发相关，而 AMM 与黑色素瘤家族史、超过 50 个痣和发育不良痣史呈负相关。与 PMM 相比，AMM 更可能位于头部和/或颈部，具有更具侵袭性的病理特征（更大的 Breslow 深度和/或有丝分裂、溃疡、结节亚型），并且不太可能与前体痣相关或回归。最后，AMM 患者比 PMM 患者更容易被误诊（临床上分别为 25% 和 12%，病理上分别为 12% 和 7%），并且他们的黑色素瘤特异性生存率较低（5 年总生存率，0.77 [...] 95% 置信区间，0.72-0。

限制

回顾性研究设计，单机构研究。

结论

更高的临床医生意识、更低的活检阈值和增加的患者教育可能有助于增强具有某些特征的患者的 AMM 检测。