Spindle Cell and Pleomorphic Lipoma

Spindle Cell and Pleomorphic Lipoma
Amitabh Srivastava, MD
Spindle cell and pleomorphic lipomas are well-circumscribed tumors with a pale yellow, homogeneous appearance that lacks the lobular configuration seen in typical lipomas.
Spindle cell lipomas show mature adipocytes admixed with a bland spindle cell proliferation in a dense collagenous stroma.
TERMINOLOGY
Abbreviations
  • Spindle cell lipoma (SCL)/pleomorphic lipoma (PL)
Definitions
  • Benign adipocytic tumor with variable admixture of spindle cells, ropey collagen, and multinucleated tumor giant cells
CLINICAL ISSUES
Epidemiology
  • Age
    • Typically in older age group (> 50 years)
  • Gender
    • Predominantly in men; < 10% in women
Site
  • Shoulder and posterior neck most common sites of involvement
  • Other sites
    • Upper arm
    • Face
    • Oral cavity
  • Lower extremity involvement is rare
Presentation
  • Painless mass
    • Dermal or subcutaneous nodule
    • Often present for long duration
    • Rarely multiple or familial
Treatment
  • Conservative surgical excision is adequate
Prognosis
  • Benign behavior
  • Local recurrence is rare
MACROSCOPIC FEATURES
Gross Appearance
  • Well-circumscribed tumor
  • Yellow-gray white appearance
  • Firm consistency
  • Some cases may show myxoid appearance
MICROSCOPIC PATHOLOGY
Histologic Features
  • Spindle cell lipoma is composed of variable admixture of 3 components
    • Mature adipocytes
    • Bland spindle cell proliferation
    • Myxoid stroma with ropey collagen and mast cells
  • Pleomorphic lipoma is part of same spectrum
    • In addition to above features, also shows multinucleated tumor giant cells with peripherally arranged nuclei (“floret cells”)
    • Lipoblasts may be present in pleomorphic lipoma
Cytologic Features
  • Bland nuclei in spindle cell lipoma
  • Hyperchromatic nuclei in multinucleated tumor giant cells in pleomorphic lipoma
Variants
Jul 8, 2016 | Posted by in PATHOLOGY & LABORATORY MEDICINE | Comments Off on Spindle Cell and Pleomorphic Lipoma

Full access? Get Clinical Tree

Get Clinical Tree app for offline access