Histology:
DIAGNOSTIC SUMMARY: Lung: Metastatic melanoma.
Macroscopic Description: Labelled "lung biopsy", the specimen consists of eight dark brown haemorrhagic cores 5, 6, 7, 7, 9, 15, 15 and 18mm. All embedded. Block 1A- four longest cores; 1B- four shorter cores. [AW]
Microscopic Description: Lung. The multiple core biopsies, which consist virtually entirely of lesional tissue, show metastatic melanoma. The tumour is composed of sheets, cords and nests of intermediate to large epithelioid cells with a moderate amount of densely eosinophilic cytoplasm. There is moderate nuclear pleomorphism with some large rounded nuclei with prominent nucleoli. Some melanin pigment is noted in some tumour cells. Prominent sheets of heavily pigmented melanophages are present. Foci of tumour necrosis are noted. Mitotic activity appears brisk with in the order of 20 mitoses per square millimetre noted. Neither lymphovascular space invasion nor perineural invasion is noted. immunoperoxidase studies: S100: Positive SOX10: Positive MART-1: Positive HMB45: Positive BRAF v600e (IHC): Negative