A bone biopsy was performed, and its result evidenced medullary fibrosis, chronic inflammation with multinucleated of giant cells and areas fusocellular
proliferation, compatible with chronic osteomyelitis.
Microscopic examination revealed a fusocellular proliferation encapsulated by a thick fibrous capsule (Figure 2).
Caption: Figure 2: Fusocellular proliferation encapsulated by a thick fibrous capsule compressing the nodal tissue (HE, 100x).
Pathological findings were of a solitary fibrous tumor which had variable cellularity, moderate to high, with a morphological pattern predominantly fusocellular
without formation of bundles, in a haemangiopericytic arrangement, with sclerotic stroma.
There are three histologic variants of Histoid Hansens: Pure fusocellular
with epithelioid component and fusocellular
with vacuolated cells.
However hypointense lesions in the T2-weighted MRI images have also been reported which the authors associated with the dense fusocellular
nature of the tumour .
Three pathological patterns of histoid leprosy include: pure fusocellular
with epithelioid components, and fusocellular
with vacuolated cells (the most common pattern).
(24) The dense connective tissue is sub-categorized as: i) unidirectional parallel ordered dense connective tissue, ii) multidirectional parallel ordered dense connective tissue, iii) woven connective tissue, iv) irregular fusocellular
Histologically, renal leiomyomas appear to be made of fusocellular
elements showing the absence of mitotic figures, pleomorphism, hypercromatism and, above all, the absence of perilesional invasivity.
In addition, a fusocellular
pattern with brisk mitotic activity (31 per 10 high-power fields) was also present (Figure, a and d).