| Cryptococcal
inflammatory pseudotumors.Am
J Surg Pathol. 2007 Oct;31(10):1521-7.
"Inflammatory
pseudotumors" (IPTs) embrace a heterogeneous spectrum of reactive,
infective, and neoplastic entities, that are characterized by a clinical
mass composed of a histologic proliferation of spindle cells in a background
of inflammatory cells and collagen fibers. Although a spectrum of
microorganisms have been identified in infective IPTs, mycobacterial
infective IPTs are reported most commonly. We document 5 solitary
cryptococcal IPTs, in 2 males and 3 females, aged 19 to 43 years, in the
soft tissues of the anterior chest wall, thigh, and arm. All were
HIV-positive and had been treated for disseminated cutaneous and/or
meningeal cryptococcosis with antifungal therapy, 6 to 12 months earlier.
The specimens demonstrated a storiform arrangement of plump spindle cells,
in addition to spindle and polygonal cells that were arranged in a haphazard
manner. Background lymphocytes, plasma cells, and fibrosis were noted, in
addition to scattered giant cells and focal necrosis. On high-power
examination, Cryptococcus neoformans yeasts were identified within and
between vacuolated spindle and polygonal cells on routine and special
stains, confirming cryptococcal IPTs. Immunophenotyping of the spindle cells
confirmed a mixed histiocytic and myofibroblastic lineage, with a
predominance of the former. In documenting 5, hitherto unreported,
pseudotumoral spindle cell reactions to C. neoformans, we not only highlight
the need for intense appraisal of all IPTs for infective agents on routine
and special stains and investigations, but also postulate that a complex
host-fungus interaction, coupled with an exuberant, myofibroblastic response
to incomplete therapy, are the pathogenetic drive for the pseudotumoral
presentation. |