Clinicopathological characteristics of cutaneous melanocytic tumor with CRTC1::TRIM11 fusion of three cases
10.3760/cma.j.cn112151-20250402-00229
- VernacularTitle:CRTC1：：TRIM11融合性皮肤黑色素细胞肿瘤3例临床病理学特征
- Author:
Yuanyuan XU
1
;
Botao FAN
;
Le XIE
;
Yingxin HUANG
;
Hongling LI
;
Jinhui ZHANG
;
Xuxuan WEI
;
Rongjun MAO
Author Information
1. 广州中医药大学第八临床医学院佛山市中医院病理科，佛山 528000
- Publication Type:Journal Article
- Keywords:
Melanoma;
Immunohistochemistry;
Genes;
In situ hybridization, fluorescence;
CRTC1::TRIM11
- From:
Chinese Journal of Pathology
2025;54(12):1270-1275
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinicopathological characteristics and diagnostic criteria of cutaneous melanocytic tumor with CRTC1::TRIM11 fusion (CMTCT), and to improve understanding of this entity.Methods:The clinical features, histology, immunohistochemistry (IHC) and molecular characteristics of 3 CMTCT cases were analyzed, supplemented by a literature review.Results:All patients were female, aged 53, 46 and 46 years, respectively. Grossly, the lesions presented as dermal/subcutaneous nodules protruding from the skin surface. Histologically, tumor cells were arranged in nested and fascicular patterns separated by delicate fibrous septa. Tumor cell infiltration was observed in the epidermis of case 1, but not in that of cases 2 and 3. Tumor cells exhibited epithelioid, spindle-shaped, or oval morphology, with eosinophilic or pale cytoplasm and mild to moderate nuclear atypia. Tumor mitotic figure was <5/10 HPF. Scant melanin pigment was observed in case 2. IHC demonstrated diffuse and strong positivity for SOX-10, S-100 protein and MITF. HMB45 was negative in two cases (case 1 and case 3) and focally positive in case 2; Melan A was negative in two cases (case 1 and case 3) and partially positive in case 2. The Ki-67 proliferation index was approximately 5%-8%. Molecular analysis revealed CRTC1::TRIM11 fusion in three cases via RNA sequencing, and CRTC1 rearrangement in two cases (case 1 and case 3) via fluorescence in situ hybridization.Conclusions:CMTCT shares histological and immunophenotypic features with melanoma and clear cell sarcoma but is defined by the presence of CRTC1::TRIM11 fusion, necessitating molecular confirmation for definitive diagnosis. Complete excision with clear margins is recommended. While most of the CMTCTs exhibit indolent biological behaviors, rare cases may recur locally or metastasize, warranting close follow-up.
