ALK+ inflammatory myofibroblastic tumor

Inflammatory myofibroblastic tumour has been allocated to the intermediate (rarely metastasizing) category.

They are regarded as neoplasms which, in children, are quite often characterized by ALK-1 gene rearrangements, and which may recur or metastasize in as many as 5% of cases. Unfortunately, aggressive behaviour cannot always be predicted on morphological grounds.

Localization

 soft tissues
 urinary bladder
 uterus (16160478)

Variants

 neonatal case (15991166, 14577098, 12574774)
 aggressive inflammatory myofibroblastic tumour
 atypical inflammatory myofibroblastic tumour

Prognosis

 rare metastases (15747099)

• rare pulmonary metastases (15747099)

Immunochemistry

 smooth muscle actin + (SMA +)
 ALK + (11684952)

Cytogenetics

 2p23 rearrangement (ALK)

• 19p13.1 (TPM4)
• 1q22.23 (TPM3)
• 17q23 (CLTCL2)

Molecular biology

 ALK/TPM4 fusion gene ( at 19p13.1)
 ALK/TPM3 fusion gene(at 1q22.23)
 ALK/CLTCL2 fusion gene (at 17q23)
 ALK/CARS fusion gene (13679433)

See also

 inflammatory pseudotumor

References

 Inflammatory myofibroblastic tumor versus IgG4-related sclerosing disease and inflammatory pseudotumor: a comparative clinicopathologic study. Yamamoto H, Yamaguchi H, Aishima S, Oda Y, Kohashi K, Oshiro Y, Tsuneyoshi M. Am J Surg Pathol. 2009 Sep;33(9):1330-40. PMID: 19718789

 Inflammatory myofibroblastic tumor: comparison of clinicopathologic, histologic, and immunohistochemical features including ALK expression in atypical and aggressive cases. Coffin CM, Hornick JL, Fletcher CD. Am J Surg Pathol. 2007 Apr;31(4):509-20. PMID: 17414097

 The evolving classification of soft tissue tumours: an update based on the new WHO classification. Fletcher CD. Histopathology. 2006 Jan;48(1):3-12. PMID: 16359532

 Mergan F, Jaubert F, Sauvat F, et al. Inflammatory myofibroblastic tumor in children: clinical review with anaplastic lymphoma kinase, Epstein-Barr virus, and human herpesvirus 8 detection analysis. J Pediatr Surg 2005;40:1581–1586.

 Yamamoto H, Oda Y, Saito T, et al. p53 Mutation and MDM2 amplification in inflammatory myofibroblastic tumours. Histopathology 2003;42:431–439.

 Identification of CARS-ALK fusion in primary and metastatic lesions of an inflammatory myofibroblastic tumor. Debelenko LV, Arthur DC, Pack SD, Helman LJ, Schrump DS, Tsokos M. Lab Invest. 2003 Sep;83(9):1255-65. PMID: 13679433

 Cook JR, Dehner LP, Collins MH, Ma Z, Morris SW, Coffin CM, Hill DA. Anaplastic lymphoma kinase (ALK) expression in the inflammatory myofibroblastic tumor: a comparative immunohistochemical study. Am J Surg Pathol. 2001 Nov;25(11):1364-71. PMID: 11684952

 Coffin CM, Patel A, Perkins S, et al. ALK1 and p80 expression and chromosomal rearrangements involving 2p23 in inflammatory myofibroblastic tumor. Mod Pathol 2001;14:569–576.

 Griffin CA, Hawkins AL, Dvorak C, et al. Recurrent involvement of 2p23 in inflammatory myofibroblastic tumors. Cancer Res 1999;59:2776–2780.

 Coffin CM, Watterson J, Priest JR, Dehner LP. Extrapulmonary inflammatory myofibroblastic tumor (inflammatory pseudotumor). A clinicopathologic and immunohistochemical study of 84 cases. Am J Surg Pathol. 1995 Aug;19(8):859-72. PMID: 7611533

 Souid AK, Ziemba MC, Dubansky AS, et al. Inflammatory myofibroblastic tumor in children. Cancer 1993;72:2042–2048.