Myofibroma, Solitary and Multicentric

Definition

• Generally biphasic tumor composed of mature and immature myofibroblastic cells with hemangiopericytoma-like vessels. May be solitary or multicentric

Alternate / Historical Names

• Congenital fibrosarcoma
• Congential generalized fibromatosis
• Infantile hemangiopericytoma
• Infantile myofibromatosis
• Myofibromatosis

Diagnostic Criteria

• Superficial lesions circumscribed, deep lesions infiltrative
  • Both may be microscopically infiltrative
• Generally biphasic nodules (see below for exceptions)
  • Light staining bundles of mature spindle cells usually on periphery of nodules
    • Moderate amount of well defined cytoplasm
    • Generally vesicular nuclei
    • Peripheral chronic inflammation may be present
  • Dark staining areas of primitive oval to spindle cells usually in center of nodules
    • Scant indistinct cytoplasm
• Small dark nuclei
• Hemangiopericytoma-like vascular pattern
• Mitotic figures may be frequent
  • No atypical figures
• Intravascular growth frequent
  • No clinical significance
• Mild pleomorphism may be present
  • No clinical significance
• Central necrosis may be present
  • Rare in infants
• Both cell types actin positive
• Exceptions to usual pattern
  • Occasional domination of either type
  • Mature cell type more predominant in lung
  • Immature cell type more predominant in bone
  • Reversal of zonation occasionally seen in adults
• Infantile lesions show common features with infantile hemangiopericytoma
  • We consider them to be the same entity
• Adult lesions have been proposed as part of a spectrum including glomangiopericytoma and myopericytoma

Richard L Kempson MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting: August 10, 2008

Supplemental studies

Immunohistology

Differential diagnosis

• Infantile hemangiopericytoma
• Glomangiopericytoma and Myopericytoma
• Inflammatory myofibroblastic tumor
• Infantile fibrosarcoma
• Solitary fibrous tumor
• Adult hemangiopericytoma
• Leiomyoma
• Nodular fasciitis
• Fibrous hamartoma of infancy
• Inclusion body fibromatosis
• Myofibroma

Lesions that may demonstrate a prominent hemangiopericytoma-like vascular pattern

• Cellular angiofibroma
• Deep fibrous histiocytoma
• Endometrial stromal sarcoma
• Glomangiopericytoma
• Glomus tumor
• Hemangiopericytoma
• Infantile fibrosarcoma
• Leiomyosarcoma
• Mesenchymal chondrosarcoma
• Myofibroma (infantile hemangiopericytoma)
• Myopericytoma
• Sinonasal hemangiopericytoma
• Solitary fibrous tumor
• Synovial sarcoma

Clinical

• Location
  • Skin, subcutaneous tissue, muscle
    • Bones, organs less common
  • Head, neck, trunk most common
  • Rarely seen in almost any other site
• 75% solitary lesions
  • Solitary lesions usually superficial
• Multiple lesions may be few to >100
  • Cases with multiple lesions may be superficial or deep and include more organ involvement
• Age
  • 90% <2 years
  • 60% near birth
  • Rare in adults
    • Usually single
    • Usually superficial
    • Infrequent recurrence
    • Usually on head, neck, upper trunk
• May show autosomal dominant inheritance
  • Rarely associated with congenital defects
• Clinical appearance
  • 0.5 to >7 cm
  • May be white or purple nodule
  • May appear to be a scar
• May show growth after birth with later stabilization or regression
• Individual lesions cured by excision
  • May not be possible in multifocal cases with visceral involvement
• Visceral involvement may cause death

Bibliography

• Kempson RL, Fletcher CDM, Evans HL, Henrickson MR, Sibley RS. Tumors of the Soft Tissues, Atlas of Tumor Pathology, AFIP Third Series, Fascicle 30, 2001
• Fletcher CDM, Unni KK, Mertens F. Pathology and Genetics of Tumours of Soft Tissue and Bone, World Health Organization Classification of Tumours 2002
• Weiss SW, Goldblum JR. Enzinger and Weiss's Soft Tissue Tumors, 5th edition, 2008
• Daimaru Y, Hashimoto H, Enjoji M.  Myofibromatosis in adults (adult counterpart of infantile myofibromatosis).  Am J Surg Pathol 1989 Oct;13(10):859-65.
• Fletcher CD, Achu P, Van Noorden S, McKee PH.  Infantile myofibromatosis: a light microscopic, histochemical and immunohistochemical study suggesting true smooth muscle differentiation.  Histopathology 1987 Mar;11(3):245-58.
• Granter SR, Badizadegan K, Fletcher CD.  Myofibromatosis in adults, glomangiopericytoma, and myopericytoma: a spectrum of tumors showing perivascular myoid differentiation.  Am J Surg Pathol 1998 May;22(5):513-25.
• Jennings TA, Duray PH, Collins FS, Sabetta J, Enzinger FM.  Infantile myofibromatosis. Evidence for an autosomal-dominant disorder.  Am J Surg Pathol 1984 Jul;8(7):529-38.
• Bracko M, Cindro L, Golouh R.  Familial occurrence of infantile myofibromatosis.  Cancer 1992 Mar 1;69(5):1294-9.
• Briselli MF, Soule EH, Gilchrist GS.  Congenital fibromatosis: report of 18 cases of solitary and 4 cases of multiple tumors.  Mayo Clin Proc 1980 Sep;55(9):554-62
• Chung EB, Enzinger FM.  Infantile myofibromatosis.  Cancer 1981 Oct 15;48(8):1807-18.
• Mentzel T, Calonje E, Nascimento AG, Fletcher CD.  Infantile hemangiopericytoma versus infantile myofibromatosis. Study of a series suggesting a continuous spectrum of infantile myofibroblastic lesions.  Am J Surg Pathol 1994 Sep;18(9):922-30.
• Speight PM, Dayan D, Fletcher CD.  Adult and infantile myofibromatosis: a report of three cases affecting the oral cavity.  J Oral Pathol Med 1991 Sep;20(8):380-4.
• Hogan SF, Salassa JR.  Recurrent adult myofibromatosis. A case report.  Am J Clin Pathol 1992 Jun;97(6):810-4.Spraker MK, Stack C, Esterly NB.  Congenital generalized fibromatosis: a review of the literature and report of a case associated with porencephaly, hemiatrophy, and cutis marmorata telangiectatica congenita.  J Am Acad Dermatol 1984 Feb;10(2 Pt 2):365-71.