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

CLASSIFICATIONS

Hamburg classification 1993(surgeons, pathologists)Truncular and extratruncular lesionsVM/LM/AVM/combined

ISSVA Classification 1982/1996

(clinical)tumors and malformations : slow Flow and high Flow

New ISSVA classification March 2014Updated 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

• Clinically obvious

• From birth

• Initially ASx

• Watch for deeper, more dangerous lesion!

Capillary malformations (CM)a.k.a. cutaneous angioma

MG8

MG7

Diapositive 11

MG8 Usually known as “Port-wine stain”

Eventually soft tissue & bony overgrowthMarie-France Giroux; 11/05/2015

MG7 Actually, this patient has Klippel-Trenaunay syndromeMarie-France Giroux; 11/05/2015

Lymphatic malformation

• Cystic cavity lined by an endothelial layer filled by a lymphatic fluid

• ML macrocystic (> 2cm3)

• ML microcystic (< 2cm3)

• 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

Stage 1: Quiescent• Pink-bluish stain

• Warm

• Arteriovenous shunting (DUS)

(Clinical staging system to grade the evolution of AVMs)

Schobinger classification Stage 2: Expansion

• Darkening blush stain

• Pulsations

• Thrill

• Bruit

• Tortuous/tense veins

Stage 1 +

Schobinger classification Stage 3: Destruction

• Steal • Distal ischemia • Dystrophic skin changes • Ulceration • Bleeding• Persistent pain • Tissues necrosis • Soft tissues and bones changes

Stage 2 +

Schobinger classification

Stage 4: Decompensation

• High output cardiac failure Stage 3 +

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 asKlippel–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….