Leiomyosarcoma Arising in Vessels

Definition

• Malignant neoplasm exhibiting smooth muscle differentiation arising in the lumen or wall of a vessel

Alternate/Historical Names

• Vascular leiomyosarcoma

Diagnostic Criteria

• Most commonly involves inferior vena cava or pulmonary artery
  • May involve lumenal surface or invade wall
    • Invasion into adjacent soft tissue may be seen in venous cases
• Smooth muscle differentiation
  • Elongate eosinophilic cytoplasm
  • Desmin or caldesmon stain usually positive
• Requires any one of the following
  • Cytologic pleomorphism or atypia
  • Tumor cell necrosis
  • Mitotic rate >4 per 50 HPF
• Any tumor lacking the above histologic criteria should be considered a smooth muscle tumor of uncertain malignant potential as experience with such tumors is limited

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

Original posting/updates:: 12/1/07, 7/15/10

Supplemental studies

Immunohistology

• Smooth muscle actin and muscle specific actin positive
• Desmin or caldesmon positive but may be less extensive than actin
• Keratin aind EMA may show occasional, usually patchy or dot-like staining
• S100 has been reported in smooth muscle tumors of various sites
  • The combination of actin negative and S100 positive should strongly suggest nerve sheath tumor
• CD34 is occasionally positive, usually weakly

Differential diagnosis

• Intravenous leiomyomatosis
• Intimal sarcoma
• If extravascular extension is prominent, the differential diagnosis is the same as for leiomyosarcoma of the retroperitoneum

Intimal Sarcoma	Leiomyosarcoma Arising in Vessels
Pleomorphic, histologically undifferentiated	Elongate or spindled eosinophilic cytoplasm
Typically lacks abundant desmin or caldesmon	Typically desmin or caldesmon diffusely positive
Most common in great arteries	Most common in vena cava but may involve pulmonary artery

Clinical

• Rare
• Most commonly involves inferior vena cava or pulmonary artery
  • May cause Budd Chiari syndrome or renal failure due to vascular obstruction
  • Liver compromise is strongly related to outcome
• 90% of cases in adult females

Report

• According to the guidelines of the ADASP, grading may be prognostically useful
• French Federation of Cancer Centers System (FNCLCC) grading scheme for adult sarcomas
• Tumor differentiation score = 2 for leiomyosarcoma
• Mitotic index
  • Score 1 0-9 mitoses per 10 hpf (0.1744 sq mm)
  • Score 2 10-19 mitoses per 10 hpf
  • Score 3 >19 mitoses per 10 hpf
• Tumor cell necrosis
  • Score 0 No necrosis on any slide (one slide per 2 cm tumor diameter)
  • Score 1 <50% of tumor is necrotic on slides examined
  • Score 2 >50% of tumor is necrotic on slides examined
• Final Grade (add the three scores above)
  • Grade 1 Sum of scores = 2 or 3
  • Grade 2 Sum of scores = 4 or 5
  • Grade 3 Sum of scores = 6 or more
• One large study found that neither FNCLCC grading nor the presence of necrosis correlated with outcome in IVC tumors (Laskin 2010)

Use TNM Staging

The surgical pathology report should contain or address the following:

• Location
• Type of resection or biopsy
• Histologic diagnosis
• Managerial category III (Local recurrence common; Metastasis occurs)
• Extent of tumor cell necrosis
• Grade
• Stage
• Size
• Depth (dermis, subcutis, below fascia, body cavity)
• Margins
  • Involved
  • Not involved
    • If under 2 cm give all such distances and sites
    • If over 2 cm give minimum distance and site
• Results of supplementary studies if performed
• Relationship to other specimens from the same patient

Lists

Neoplasms with predominant smooth muscle differentiation

• Angioleiomyoma
• Arrector Pili Leiomyoma
• Dermal Leiomyosarcoma (not a true sarcoma as does not metastasize)
• Leiomyoma of Deep Soft Tissue, Retroperitoneum, Mesentery and Omentum
• Leiomyosarcoma of Deep Soft Tissue, Retroperitoneum, Mesentery and Omentum
• Penile Myointimoma
• Smooth Muscle Hamartoma of Dermis
• Smooth Muscle Tumor of Uncertain Malignant Potential of various sites
• Subcutaneous Leiomyosarcoma
• Vascular Leiomyosarcoma
• Visceral Leiomyoma
• Visceral Leiomyosarcoma

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, 4th edition, 2001
• Svarvar C, Bohling T, Berlin O, Gustafson P, Folleras G, Bjerkehagen B, Domanski HA, Sundby Hall K, Tukiainen E, Blomqvist C; the Scandinavian Sarcoma Group Leiomyosarcoma Working Group. Clinical course of nonvisceral soft tissue leiomyosarcoma in 225 patients from the Scandinavian Sarcoma Group. Cancer. 2007 Jan 15;109(2):282-91.
• Hornick JL, Fletcher CD. Criteria for malignancy in nonvisceral smooth muscle tumors. Ann Diagn Pathol. 2003 Feb;7(1):60-6.
• Weiss SW. Smooth muscle tumors of soft tissue. Adv Anat Pathol. 2002 Nov;9(6):351-9.
• Demers ML, Curley SA, Romsdahl MM. Inferior vena cava leiomyosarcoma. J Surg Oncol. 1992 Oct;51(2):89-92.
• Varela-Duran J, Oliva H, Rosai J. Vascular leiomyosarcoma: the malignant counterpart of vascular leiomyoma. Cancer. 1979 Nov;44(5):1684-91.
• Kieffer E, Alaoui M, Piette JC, Cacoub P, Chiche L. Leiomyosarcoma of the inferior vena cava: experience in 22 cases. Ann Surg. 2006 Aug;244(2):289-95.
• Huo L, Moran CA, Fuller GN, Gladish G, Suster S. Pulmonary artery sarcoma: a clinicopathologic and immunohistochemical study of 12 cases. Am J Clin Pathol. 2006 Mar;125(3):419-24.
• Hilliard NJ, Heslin MJ, Castro CY. Leiomyosarcoma of the inferior vena cava: three case reports and review of the literature. Ann Diagn Pathol. 2005 Oct;9(5):259-66.
• Laskin WB, Fanburg-Smith JC, Burke AP, Kraszewska E, Fetsch JF, Miettinen M. Leiomyosarcoma of the inferior vena cava: clinicopathologic study of 40 cases. Am J Surg Pathol. 2010 Jun;34(6):873-81.