Classification des Malformations vasculaires Gilles Soulez, MD, MSc, FSIR Professeur Titulaire et Chairman Dpt Radiologie, Radio-Oncologie et Medecine Nucléaire Université de Montréal
Basic principles Use an appropriate terminology New ISSVA classification Always correlate imaging findings with clinical history and examination Phenotyping Link between genetic and phenotyping will be the key to improve our understanding and find specific therapeutic target
CLASSIFICATIO NS Hamburg classification 1993 (surgeons, pathologists) Truncular and extratruncular lesions VM/LM/AVM/combined ISSVA Classification 1982/1996 (clinical) tumors and malformations : slow Flow and high Flow New ISSVA classification March 2014 Updated May 2018
2018 ISSVA classification
Infantile hemangioma Infantile hemangioma Growth 0-1 year Stabilization 1-2 year Regression 2-5 year Glut 1 + Conservative management Propanolol, interferon, vincristin for complicated cases
Infantile hemangioma Penetration Skin, subcutaneous tissue, or both (superficial, deep, or mixed) Pattern of distribution Focal, multifocal, segmental or indeterminate Deep hemangioma Superficial segmental hemangioma
Congenital hemangioma RICH (rapidly involuted congenital hemangioma) Completely grown at birth Regression 12-14 months Glut NICH (non-involuted congenital hemangioma) Completely grown at birth No involution Growth during teenage Glut PICH Partially involutive
Kaposiform hemangioendothelioma
Capillary malformations (CM) a.k.a. cutaneous angioma Clinically obvious From birth Initially ASx Watch for deeper, more dangerous lesion! MG7 MG8
Diapositive 11 MG8 MG7 Usually known as Port-wine stain Eventually soft tissue & bony overgrowth Marie-France Giroux; 11/05/2015 Actually, this patient has Klippel-Trenaunay syndrome Marie-France Giroux; 11/05/2015
Lymphatic malformation Cystic cavity lined by an endothelial layer filled by a lymphatic fluid ML macrocystic (> 2cm 3 ) ML microcystic (< 2cm 3 ) Mixed lesion (micro-macro) Mixed lesion lymphatic and venous Present at birth Growth childhood-teenage
Venous malformation Low flow Most frequent Head and neck 40% Body 20% Limbs 40% Expansion Valsalva Dependent position Bluish coloration
VM & MRI Best examination for extension T2 (STIR), T1 and T1 fat sat post gado
Arterio-venous malformation High-flow malformation AV-shunting Nidus Congenital Expansion Teenage Pregnancy
Schobinger classification (Clinical staging system to grade the evolution of AVMs) Stage 1: Quiescent Pink-bluish stain Warm Arteriovenous shunting (DUS)
Schobinger classification Stage 2: Expansion Stage 1 + Darkening blush stain Pulsations Thrill Bruit Tortuous/tense veins
Schobinger classification Stage 3: Destruction Stage 2 + Steal Distal ischemia Dystrophic skin changes Ulceration Bleeding Persistent pain Tissues necrosis Soft tissues and bones changes
Schobinger classification Stage 4: Decompensation Stage 3 + High output cardiac failure
Associated syndromes
Klippel trenaunay Limb hypertrophy Cutaneous angioma Venous and or lymphatic R/O hypoplasia deep venous system Sclerosis of varicose vein
Unclassified
FAVA
Intramuscular hemangioma = NICH? Intra muscular vascular tumor Hypervascular No AV shunting Surgery
Vascular anomalies & genetic Consequence of improper development and maintenance of the vasculature Usually sporadic Inherited forms Genes encoding bone morphogenic protein/transforming growth factor-β (TGFβ) receptor HHT and GVM Genes producing an endothelial cell signaling complex Cerebral cavernous malformations (CCM) RASA1 capillary malformation-arteriovenous malformation (CMAVM) Weakly activating mutations in TIE2/TEK Cutaneomucosal venous malformations (VMCMs)
Vascular anomalies &genetic Inherited cases 50% of the alleles affected Inherited cases share the following features Multifocality Small size Increase in the number of lesions Some mutation carriers do not have any lesions Tissular second-hit another non-inherited mutation on the second allele of the gene
Sporadic lesions can be due only to somatic mutations 60% of VMs have TIE2/TEK mutations Mosaic somatic mutations have been identified in most type of vascular anomalies VMs, CMs, LMS, PG, NICH, RICH Genes identified in sporadic cases are ubiquitously expressed and code for proteins in major pathways with no specificity to the vasculature Somatic mutations that give rise to an isolated vascular anomaly occur in vascular ECs only More extensive mosaicism can be seen in syndromic forms, such as Klippel Trenaunay syndrome
2 major pathways
Gene associated with vascular anomalies
Gene associated with vascular anomalies (2)
Gene associated with vascular anomalies (3)
Conclusion Classification currently integrate clinical phenotyping and attempt to make a link with genetic Imaging is key for phenotyping and unfortunately is not used in the classification.