M Valdivielso-Ramos1, A Torrelo2, A Martin-Santiago3, A Hernández-Nuñez4, J M Azaña5, M Campos6, B Berenguer7, G Garnacho8, R Moreno9, I Colmenero10. 1. Dermatology Department, Hospital Infanta Leonor, Madrid, Spain. 2. Dermatology Department, Hospital Niño Jesus, Madrid, Spain. 3. Dermatology Department, Hospital Son Espases, Mallorca, Spain. 4. Dermatology Department, Hospital Fuenlabrada, Madrid, Spain. 5. Dermatology Department, Hospital Albacete, Albacete, Spain. 6. Dermatology Department, Hospital Gregorio Marañón, Madrid, Spain. 7. Plastic Surgery Department, Hospital Gregorio Marañón, Madrid, Spain. 8. Dermatology Department, Hospital Reina Sofia, Córdoba, Spain. 9. Dermatology Department, Hospital del Henares, Madrid, Spain. 10. Pathology Department, Hospital Niño Jesus, Madrid, Spain.
Abstract
IMPORTANCE: Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a recently described syndrome with distinctive cutaneous lesions. Very little is known about the histopathology of these lesions. OBJECTIVE: The purpose of the study was to evaluate the histopathological characteristics of the pink macules of the CM-AVM syndrome and to investigate if these pink macules could be classified as capillary malformations or arteriovenous malformations based on their histopathological features. DESIGN-SETTINGS-PARTICIPANTS: We conducted a retrospective multicenter study involving eight hospitals in Spain. Fifteen biopsies from pink macules of the CM-AVM syndrome were analysed and compared with five biopsies of diverse capillary malformations and three stage I arteriovenous malformations. RESULTS: Pink macules' biopsies of the CM-AVM syndrome showed similar features including a high vascular density encompassing capillaries and numerous thick-walled arterioles mainly located in the superficial dermis, a predominance of elongated over round vessels, scarce or absent erythrocytes within the lumina and discrete perivascular inflammation. CMs were characterized by an increased number of capillary-type vessels mostly rounded and located in the upper dermis. AVMs were composed by highly increased numbers of vessels with a branching pattern involving the full thickness of the dermis, without erythrocytes within the lumina. Wilms tumour 1 protein was positive in the endothelial cells both in pink macules of the CM-AVM and in arteriovenous malformations. CONCLUSIONS AND RELEVANCE: Pink macules of the CM-AVM syndrome seem to be different from capillary malformations. Our results suggest that histologically and immunohistochemically they are closer to incipient arteriovenous malformations than to capillary malformations. A deepened knowledge about the nature of these skin lesions will contribute to the better understanding of capillary malformation-arteriovenous malformation syndrome, and will open the possibility of new and more specific treatments in the future.
IMPORTANCE: Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a recently described syndrome with distinctive cutaneous lesions. Very little is known about the histopathology of these lesions. OBJECTIVE: The purpose of the study was to evaluate the histopathological characteristics of the pink macules of the CM-AVM syndrome and to investigate if these pink macules could be classified as capillary malformations or arteriovenous malformations based on their histopathological features. DESIGN-SETTINGS-PARTICIPANTS: We conducted a retrospective multicenter study involving eight hospitals in Spain. Fifteen biopsies from pink macules of the CM-AVM syndrome were analysed and compared with five biopsies of diverse capillary malformations and three stage I arteriovenous malformations. RESULTS: Pink macules' biopsies of the CM-AVM syndrome showed similar features including a high vascular density encompassing capillaries and numerous thick-walled arterioles mainly located in the superficial dermis, a predominance of elongated over round vessels, scarce or absent erythrocytes within the lumina and discrete perivascular inflammation. CMs were characterized by an increased number of capillary-type vessels mostly rounded and located in the upper dermis. AVMs were composed by highly increased numbers of vessels with a branching pattern involving the full thickness of the dermis, without erythrocytes within the lumina. Wilms tumour 1 protein was positive in the endothelial cells both in pink macules of the CM-AVM and in arteriovenous malformations. CONCLUSIONS AND RELEVANCE: Pink macules of the CM-AVM syndrome seem to be different from capillary malformations. Our results suggest that histologically and immunohistochemically they are closer to incipient arteriovenous malformations than to capillary malformations. A deepened knowledge about the nature of these skin lesions will contribute to the better understanding of capillary malformation-arteriovenous malformation syndrome, and will open the possibility of new and more specific treatments in the future.
Authors: Bede N Nriagu; Victoria R Sanders; Lionel Bercovitch; Kristen Snyder; Elizabeth A Cross; James R Treat; Sarah E Sheppard Journal: Pediatr Dermatol Date: 2021-09-28 Impact factor: 1.997