ABSTRACT
The current classification of melanocytic tumors includes clinical, pathological, and molecular data. A subset of lesions remains difficult to classify according to these complex multilayer schemes. We report two cases of deeply infiltrating melanomas with a sclerosing background. The first case occurred on the back of a middle-aged man appearing clinically as a dermatofibroma. The architectural and cytological aspects resembled those of a desmoplastic melanoma but the strong expression of both melanA and HMB45, two stainings usually reported as negative in this entity, raised the question of an alternate diagnosis. The second case was a large, slowly growing, perivulvar tumor in a middle-aged woman. The morphology was complex with a central junctional spitzoid pattern associating an epidermal hyperplasia with large nests of large spindled melanocytes. The dermal component was made of deeply invasive strands and nests of nevoid unpigmented melanocytes surrounded by fibrosis; a perineural invasion was present at the periphery of the lesion. In both cases, aCGH found, among many other anomalies, a chromosomal breakpoint at the BRAF locus. RNA sequencing identified in both an AKAP9-BRAF gene fusion. A complementary resection was performed and no relapses have been observed in the respectively 15 and 6 months of follow-up. Both of these melanomas remained unclassified. We further review the variety of melanocytic tumors associated with such BRAF fusions.
Subject(s)
A Kinase Anchor Proteins/genetics , Cytoskeletal Proteins/genetics , Melanoma/genetics , Neoplasm Recurrence, Local/genetics , Proto-Oncogene Proteins B-raf/genetics , Skin Neoplasms/genetics , Adult , Diagnosis, Differential , Female , Humans , Male , Melanoma/diagnosis , Middle Aged , Neoplasm Recurrence, Local/diagnosis , Nevus, Pigmented/diagnosis , Nevus, Pigmented/genetics , Skin Neoplasms/diagnosis , Skin Neoplasms/pathology , Melanoma, Cutaneous MalignantABSTRACT
The 2001 Bethesda System is a uniform system of terminology for reporting results of pap smears. It is acknowledged by most cytopathologists worldwide as a standard for cervical cytology reports. In France, several national surveys have confirmed its current utilization. However, more specific analysis have shown that the Bethesda System may be routinely modified by individual laboratories or even individual cytopathologist working within the same department. The aim of this progress report was to emphasize the importance of fully understanding the Bethesda System and applying it in a rigorous and standardized way.
