This video provides a histopathological examination of a large nodule filling the dermis and extending into the subcutis. The low-power view exhibits a unique grayish-pink color, a clue that suggests the presence of cells with abundant, pale cytoplasm. High-magnification microscopy confirms a sheet of cells with round/oval nuclei and abundant foamy/bubbly cytoplasm, identifying them as histiocytes. This constellation of findings leads to the diagnosis of a tuberous xanthoma. The clinical takeaway emphasizes the critical need to check the patient's serum lipid panel, as tuberous xanthomas are strongly associated with underlying dyslipidemia.
Tuberous Xanthoma: Histopathology and Clinical Correlation
0:00 Lesion Appearance: The video introduces a large, excised nodule filling the dermis and extending into the subcutis.
0:22 Low-Power Clue: The lesion displays a pink color along with a grayish-blue/grayish-pink hue, which the presenter notes is a key feature of the infiltrating cells.
0:44 Microscopic Detail: The lesion is composed of a sheet of cells exhibiting round/oval nuclei and abundant, foamy, or bubbly cytoplasm. The presenter notes that foamy cytoplasm (xanthomized cells) can be challenging to see clearly on digital scans due to its refractile nature.
1:10 Histiocyte Identification: The grayish-pink color at low power is attributed to the nuclei combined with the abundant, pale cytoplasm, which is highly characteristic of histiocytes.
1:33 Diagnosis: A large nodule made of foamy histiocytes is identified as a tuberous xanthoma.
1:41 Clinical Takeaway: Tuberous xanthomas are typically associated with abnormal serum lipid levels (dyslipidemia). Checking the patient's serum lipid panel is a crucial step in the clinical workup.