Kaneishi N K, Cockerell C J
Division of Dermatopathology, University of Texas Southwestern Medical Center, Dallas, USA.
Am J Dermatopathol. 1998 Apr;20(2):128-34. doi: 10.1097/00000372-199804000-00004.
Desmoplastic malignant melanoma (DMM) is a rare variant of melanoma that can be very difficult to diagnose correctly both clinically and histologically. The problem is compounded by the fact that many lesions persist at previous biopsy or excision sites so that scar tissue is often present admixed with or adjacent to the spindle cell neoplasm which may exhibit fibroblastic differentiation itself. In order to assess this problem, we compared and contrasted the histologic features of six DMM with 15 examples of cicatrices from various sources. Mature scars were readily differentiated from DMM by light microscopy. In contrast, immature scar and DMM had many features in common including hypercellularity, nodular lymphoid infiltrates, myxoid stroma, and atypical nuclei. The presence of a melanocytic proliferation within the epidermis above the dermal component, neurotropism, and S-100 and/or HMB-45 positivity of neoplastic cells were the only features that permitted reliable differentiation between the two. Clinical correlation and review of previous biopsy specimens are crucial in preventing a delayed diagnosis of DMM. Re-excision is advised in all questionable cases.
促纤维增生性恶性黑色素瘤（DMM）是黑色素瘤的一种罕见变体，在临床和组织学上都很难正确诊断。许多病变在先前的活检或切除部位持续存在，以至于瘢痕组织常与梭形细胞瘤混合或相邻，而梭形细胞瘤本身可能表现出成纤维细胞分化，这使得问题更加复杂。为了评估这个问题，我们将6例DMM的组织学特征与15例来自不同来源的瘢痕组织进行了比较和对照。通过光学显微镜很容易将成熟瘢痕与DMM区分开来。相比之下，未成熟瘢痕和DMM有许多共同特征，包括细胞增多、结节状淋巴细胞浸润、黏液样基质和非典型核。真皮成分上方表皮内黑素细胞增殖的存在、亲神经性以及肿瘤细胞的S-100和/或HMB-45阳性是仅有的能够可靠区分两者的特征。临床相关性以及对先前活检标本的复查对于防止DMM的延迟诊断至关重要。对于所有可疑病例，建议再次切除。
