© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
J Cutan Pathol 2014: 41: 519–523 doi: 10.1111/cup.12311 John Wiley & Sons. Printed in Singapore
Journal of Cutaneous Pathology
Nevus anelasticus: how should such lesions be classified? Nevus anelasticus represents a rare entity that is most commonly classified as a connective tissue nevus. It typically presents before 20 years of age with asymmetrically distributed white-to-skin-toned or pink-to-red papules or plaques on the trunk and upper extremities. The lesion is defined histopathologically by the absence or degeneration of elastic fibers in the dermis. We report the case of a healthy 17-year-old female who presented with an asymptomatic slowly progressive plaque on the right inferior areola. Histopathologic examination showed the absence of elastic fibers in the papillary and upper reticular dermis and fragmented elastic tissue fibers in the deep reticular dermis. Although there is ongoing controversy regarding the nosology of this uncommon disorder, we propose that it is a distinct entity based on its histopathologic and clinical features.
Keywords: connective tissue nevus, elastic tissue disorder, nevus anelasticus Wang AR, Kent K, Jagdeo J, Robinson-Bostom L, Bercovitch L. Nevus anelasticus: how should such lesions be classified?. J Cutan Pathol 2014; 41: 519–523. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Nevus anelasticus is a rare congenital or acquired disorder that presents as multiple, asymptomatic, flat, white-to-skin-toned or pink-to-red perifollicular papules measuring a few millimeters in diameter distributed asymmetrically on the upper back, chest1,2 and breasts2,3 . It is defined histopathologically by the absence or fragmentation of elastic fibers in the upper and mid-dermis1,4 . We present a case of nevus anelasticus, which highlights the classification dilemma: is nevus anelasticus a distinct entity, and should it be categorized as a connective tissue nevus or as an elastic tissue disorder? Report of a patient A healthy 17-year-old female presented with a 5-year history of gradually appearing asymptomatic white
Annie R. Wang1 , Kathryn Kent2 , Jared Jagdeo3,4,5 , Leslie Robinson-Bostom1,6 and Lionel Bercovitch1 1 Department
of Dermatology, Warren Alpert Medical School of Brown University, Providence, RI, USA, 2 SkinCare Physicians, Chestnut Hill, MA, USA, 3 Sacramento VA Medical Center, Dermatology Service, Mather, CA, USA, 4 Department of Dermatology, University of California, Davis Medical Center, Sacramento, CA, USA, 5 Department of Dermatology, State University of New York, Downstate Medical Center, Brooklyn, NY, USA, and 6 Department of Pathology, Rhode Island Hospital, Providence, RI, USA Leslie Robinson-Bostom, MD Division of Dermatopathology, Department of Dermatology, Warren Alpert Medical School of Brown University, Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903, USA Tel: +1 401 444 7137 Fax: +1 401 444 7105 e-mail: [email protected] Accepted for publication February 8, 2014
papules on the right inferior areola. Her past medical history was negative for previous dermatologic or systemic diseases and she denied any history of prior trauma to the affected area. Family history was negative for any similar lesions. Physical examination revealed multiple slightly firm, non-tender, white 2–4 mm papules arranged in a 3.2 × 0.8 cm linear cluster and distributed unilaterally on the right inferior areola (Fig. 1A). The remainder of the skin examination was normal. An excision of the lesion was performed (Fig. 1B). Sections stained with hematoxylin & eosin appeared normal (Fig. 2A). Weigert’s resorcin-fuchsin stain revealed the absence of elastic fibers extending from the papillary dermis to the upper reticular dermis (Fig. 2B) in lesional skin as compared to unaffected
519
Wang et al. A
B
Fig. 1. Right areola shows a linear cluster of white papules (A); there is well-healed surgical incision 4 months following excision (B).
tissue at the apices of the excision specimen (Fig. 2C). Sparse fragmented elastic fibers were noted in the deep reticular dermis (Fig. 2D). There has been no recurrence 5 years post-operatively. Discussion Nevus anelasticus typically presents as multiple flat white, skin-colored or pink-to-red 1–5 mm perifollicular papules, which are asymmetrically distributed over the chest and arms. These lesions may progress slowly over years. Routinely-stained sections usually appear normal. Elastic tissue staining may show the loss of elastic fibers and the fragmentation of residual elastic fibers in the papillary and upper reticular dermis without significant changes in the arrangement or size of collagen bundles1,4 . The clinical differential diagnosis for nevus anelasticus includes eruptive collagenoma and papular elastorrhexis. The histopathologic differential diagnosis includes anetoderma and mid-dermal elastolysis (Table 1). All of these disorders have a slight predominance for females and tend to appear during adolescence to young adulthood, with the exception of eruptive collagenoma, which has no age predilection. Eruptive collagenoma, classified as a connective tissue nevus, presents with an acute onset of multiple asymptomatic skin-colored sclerotic papules distributed symmetrically on the trunk and arms5 . Routine staining shows thick, loosely arranged collagen fibers, which distinguishes this entity from the other differential diagnoses. Elastic tissue stains may show decreased6 , degenerated7 or absence of8,9 elastic fibers throughout the dermis. Papular elastorrhexis most commonly presents as multiple discrete asymptomatic, non-follicular 1–5 mm flat, firm, monomorphic white-to-yellow papules, which are scattered on the trunk, the upper extremities and thighs10 . Routine staining may show a superficial and deep perivascular lymphohistiocytic infiltrate11 . Elastic tissue stain reveals thinned, fragmented or nearly complete loss of elastic fibers in the
520
reticular dermis4,11,12 . The arrangement of collagen fibers may vary from normal to homogenized and condensed9 . It was previously suggested that perhaps nevus anelasticus and eruptive collagenomas should be considered variants of papular elastorrhexis13 . However, given the unilateral distribution of nevus anelasticus along with the histopathological absence of elastic fibers from both the papillary and upper reticular dermis with sparse deep dermal elastic fiber fragments, we believe this particular case supports the argument that nevus anelasticus is a distinct entity. The histopathologic differential diagnosis includes anetoderma, an elastic tissue disorder characterized by round to oval, skin-colored or white-to-blue, flaccid, well-circumscribed 0.5–2 cm papules or plaques of slack skin, which may herniate inward on palpation14 . These are most commonly located symmetrically on the trunk, upper arms and thighs14 . Routine staining may appear normal or may show a predominantly perivascular mixed infiltrate with or without multinucleated giant cells showing elastophagocytosis.15,16 Elastic tissue staining may show variable patterns of loss and fragmentation of dermal elastic fibers, such as in the upper and lower reticular dermis or throughout the dermis17 . Mid-dermal elastolysis is an acquired elastic tissue disorder, which often presents as well-demarcated areas of perifollicular papules or fine wrinkling with inflammatory skin changes such as reticular erythema18 on the trunk or proximal extremities. Whereas routinely-stained sections may show similar patterns to those described in inflammatory anetoderma, it is histopathologically distinguished by the absence of elastic fibers exclusively in the mid-dermis18 . The classification of nevus anelasticus has been a topic of ongoing debate since its introduction in 1921. Lewandowsky initially proposed the term naevus elasticus regionis mammariae after describing three cases that clinically presented with acquired non-evolving white-to-yellow, round, firm, clustered perifollicular papules on the anterior chest2 . Histopathologically, these lesions were characterized by a normal appearance in hematoxylin & eosin and von Gieson stains along with degenerated and absent elastic fibers in the papillary and upper reticular dermis with Unna Tanzer orcein stains2 . The term nevus elasticus was subsequently coined to describe a connective tissue nevus that primarily involved an abnormality in elastic tissue composition19 . Subsequently, Staricco and Mehregan redefined nevus elasticus as a connective tissue nevus with increased elastic tissue, and argued for limiting the usage of nevus anelasticus
Nevus anelasticus classification A
B
2b
C
2c
D
Fig. 2. (A) In a hematoxylin/eosin stain, there is normal-appearing collagen (×10). B and C) Weigert’s resorcin-fuchsin stain shows (B) absence of elastic fibers in the papillary, upper and mid-reticular dermis (×20) compared to (C) normal elastic fiber pattern in the papillary dermis (×20). D). Weigert’s resorcin-fuchsin stain shows sparse fragmented elastic fibers (arrow) in the deep reticular dermis (×40).
to connective tissue nevus with decreased elastic tissue20 . Meanwhile, over the past several decades, the definition of a connective tissue nevus has evolved to represent a hamartoma with an accumulation of one of the components of the dermis: collagen, elastic tissue or glycosaminoglycans19 . In the past, it had been proposed that the classification of connective tissue nevi should be based on the portion of the dermis affected, the reticular vs. the adventitial, and not on the actual concentration of dermal components21 . Nevus anelasticus historically falls under the category of ‘nevi of reticular connective tissue’ based on the location of dermal-content irregularity. ‘Nevi of reticular connective tissue’ has been described as ‘‘a circumscribed, intradermal nodule, sparse of cells and endophytic or exophytic upon a broad base’’21 . However, nevus anelasticus does not match this pathologic description, and thus this classification system would not suffice. It has also been suggested that nevus anelasticus would be better categorized as an elastic tissue disorder variant rather than a connective tissue
nevus22 as nevus anelasticus is histopathologically characterized by a decrease in elastic tissue relative to a normal amount of collagen. Previously, certain collagenomas have been shown to have patterns of decreased elastic fibers, but was later suggested to result from a dilutional effect because of alterations in the arrangement of collagen bundles in the dermis rather than a true decrease in elastic fibers4 . However, nevus anelasticus is generally believed to be a true elastic fiber abnormality and not secondary to a dilutional affect. Thus, Lewis et al. proposed that nevus anelasticus would be better classified as an elastic tissue disorder22 . Both the rarity and ambiguous nosology of nevus anelasticus have made it difficult to identify, classify and understand this disorder. To our knowledge, only two other reports of nevus anelasticus have been previously published in the English literature2,20 . The pathogenesis, however, remains unknown. While nevus anelasticus is clinically nevoid in appearance, based upon its histopathologic features, we believe it would be more appropriately categorized as a distinct elastic tissue disorder.
521
Wang et al. Table 1. Clinical and histopathologic differential for nevus anelasticus Clinical differential diagnosis
Histopathologic differential diagnosis
Eruptive
Papular
Nevus anelasticus
collagenoma
elastorrhexis
Anetoderma
elastolysis
Clinical morphology
Multiple flat white-toskin-toned or pink-red colored 1–5 mm perifollicular papules
Multiple asymptomatic skin-colored sclerotic papules
Multiple discrete asymptomatic, non-follicular 1–5 mm flat, firm, monomorphic white-to-yellow papules
Oval, skin-colored or white-to-blue, flaccid, wellcircumscribed 0.5–2 cm papules or plaques of slack skin
Well-demarcated perifollicular papules or areas of fine wrinkling with inflammatory skin changes
Distribution
Chest, arms
Trunk, arms
Trunk, the upper extremities and thighs
Trunk, upper arms and thighs
Proximal extremities and trunks
Symmetrical?
No
Yes
Yes
Yes
Yes
Hematoxylin & eosin stain
Normal
Thick, loosely arranged collagen fibers
Superficial and deep perivascular lymphohistiocytic infiltrate
Normal without signs of inflammation, or may show a predominantly perivascular mixed infiltrate
Normal without signs of inflammation, or may show a predominantly perivascular mixed infiltrate
Elastic tissue stain
Loss of elastic fibers and fragmentation of residual elastic fibers in the papillary and upper reticular dermis. No changes in the arrangement or size of collagen bundles
Decreased, degenerated, or absent elastic fibers throughout the dermis
Variable patterns of Thinned, fragmented, loss and or nearly complete fragmentation of loss of elastic fibers dermal elastic in the reticular fibers, such as in dermis. Collagen upper and lower fibers may vary from reticular dermis or normal to throughout the homogenized and dermis condensed
Acknowledgements Wang AR, Jagdeo J, Bercovitch L, RobinsonBostom L. ‘Nevus Anelasticus: a rare case of uncertain classification’, presented at Gross & Micro
Mid-dermal
Absence of elastic fibers exclusively in the mid-dermis
Symposium, American Academy of Dermatology Annual Meeting 4–8 February, 2011, New Orleans, LA. The authors would like to acknowledge the assistance of Florian Froehlich in translating reference 2 by Lewandowsky.
References 1. Crivellato E. Disseminated nevus anelasticus. Int J Dermatol 1986; 25: 171. 2. Lewandowsky F. Uber einen eigentumlichen naevus der brustgegend. Arch Derm Syph 1921; 131: 90. 3. Del Pozo J, Martinez W, Sacristan F, Fernandez-Jorge B, Fonseca E. Papular elastorrhexis, a distinctive entity? Am J Dermatopathol 2008; 30: 188. 4. Sears JK, Stone MS, Argenyi Z. Papular elastorrhexis: a variant of connective tissue nevus. J Am Acad Dermatol 1988; 19: 409. 5. Henderson RR, Wheeler CE, Abele DC. Familial cutaneous collagenoma. Arch Dermatol 1968; 98: 23.
522
6. Amaya M, Okubo Y, Koga M. A case of eruptive collagenoma localized on the neck and shoulders. J Dermatol 2002; 29: 79. 7. Lee MW, Choi JH, Sung KJ, Moon KC, Koh JK. A case of eruptive collagenoma. Pediatr Dermatol 2002; 19: 565. 8. Smith LR, Bernstein BD. Eruptive collagenoma. Arch Dermatol 1978; 114: 1710. 9. Ryder HF, Antaya RJ. Nevus anelasticus, papular elastorrhexis, and eruptive collagenoma: clinically similar entities with focal absence of elastic fibers in childhood. Pediatr Dermatol 2005; 22: 153. 10. Buechner SA, Itin P. Papular elastorrhexi: report of five cases. Dermatology 2002; 205: 198.
11. Bordas X, Ferrandiz C, Ribera M, Galofre E. Papular elastorrhexis: a variety of nevus anelasticus? Arch Dermatol 1987; 123: 433. 12. Schirren H, Schirren CG, Stolz W, et al. Papular elastorrhexis: a variant of dermatofibrosis lenticularis disseminata (Buschke–Ollendorff syndrome). Dermatology 1994; 189: 368. 13. Choonhakarn C, Jiratattanapochai K. Papular elastorrhexis: a distinct variant of connective tissue nevi or an incomplete form of BuschkeOllendorff syndrome? Clin Exp Dermatol 2002; 27: 454. 14. Venencie PY, Winkelmann RK, Moore BA. Anetoderma: clinical findings, associations, and long term follow-up evaluations. Arch Dermatol 1984; 120: 1032.
Nevus anelasticus classification 15. Kossard S, Kronman KR, Dicken CH, Schroeter AL. Inflammatory macular atrophy: immunofluorescent and ultrastructural findings. J Am Acad Dermatol 1979; 1: 325. 16. Zaki I, Scerri L, Nelson H. Primary anetoderma: phagocytosis of elastic fibres by macrophages. Clin Exp Dermatol 1994; 19: 388. 17. Oikarinen AI, Palatsi R, Adomian GE, Oikarinen H, Clark JG, Uitto J. Anetoderma: biochemical and ultrastructural demonstration of an elastin defect in the skin of
three patients. J Am Acad Dermatol 1984; 11: 64. 18. Shelley WB, Wood MG. Wrinkles due to idiopathic loss of mid-dermal elastic tissue. Br J Dermatol 1977; 97: 441. 19. Uitto J, Santa Cruz DJ, Eisen AZ. Connective tissue nevi of the skin: clinical, genetic, and histopathologic classification of hamartomas of the collagen, elastin, and proteoglycan type.
20. Staricco RG, Mehregan AH. Nevus elasticus and nevus elasticus vascularis. Arch Dermatol 1961; 84: 943. 21. Pierard GE, Lapiere CM. Nevi of connective tissue: a reappraisal of their classification. Am J Dermatopathol 1985; 7: 325. 22. Lewis K, Bercovitch L, Dill SW, RobinsonBostom L. Acquired disorders of elastic tissue: part II. Decreased elastic tissue. J Am Acad Dermatol 2004; 51: 165.
J Am Acad Dermatol 1980; 3: 441.
523
J Cutan Pathol 2014: 41: 519–523 doi: 10.1111/cup.12311 John Wiley & Sons. Printed in Singapore
Journal of Cutaneous Pathology
Nevus anelasticus: how should such lesions be classified? Nevus anelasticus represents a rare entity that is most commonly classified as a connective tissue nevus. It typically presents before 20 years of age with asymmetrically distributed white-to-skin-toned or pink-to-red papules or plaques on the trunk and upper extremities. The lesion is defined histopathologically by the absence or degeneration of elastic fibers in the dermis. We report the case of a healthy 17-year-old female who presented with an asymptomatic slowly progressive plaque on the right inferior areola. Histopathologic examination showed the absence of elastic fibers in the papillary and upper reticular dermis and fragmented elastic tissue fibers in the deep reticular dermis. Although there is ongoing controversy regarding the nosology of this uncommon disorder, we propose that it is a distinct entity based on its histopathologic and clinical features.
Keywords: connective tissue nevus, elastic tissue disorder, nevus anelasticus Wang AR, Kent K, Jagdeo J, Robinson-Bostom L, Bercovitch L. Nevus anelasticus: how should such lesions be classified?. J Cutan Pathol 2014; 41: 519–523. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Nevus anelasticus is a rare congenital or acquired disorder that presents as multiple, asymptomatic, flat, white-to-skin-toned or pink-to-red perifollicular papules measuring a few millimeters in diameter distributed asymmetrically on the upper back, chest1,2 and breasts2,3 . It is defined histopathologically by the absence or fragmentation of elastic fibers in the upper and mid-dermis1,4 . We present a case of nevus anelasticus, which highlights the classification dilemma: is nevus anelasticus a distinct entity, and should it be categorized as a connective tissue nevus or as an elastic tissue disorder? Report of a patient A healthy 17-year-old female presented with a 5-year history of gradually appearing asymptomatic white
Annie R. Wang1 , Kathryn Kent2 , Jared Jagdeo3,4,5 , Leslie Robinson-Bostom1,6 and Lionel Bercovitch1 1 Department
of Dermatology, Warren Alpert Medical School of Brown University, Providence, RI, USA, 2 SkinCare Physicians, Chestnut Hill, MA, USA, 3 Sacramento VA Medical Center, Dermatology Service, Mather, CA, USA, 4 Department of Dermatology, University of California, Davis Medical Center, Sacramento, CA, USA, 5 Department of Dermatology, State University of New York, Downstate Medical Center, Brooklyn, NY, USA, and 6 Department of Pathology, Rhode Island Hospital, Providence, RI, USA Leslie Robinson-Bostom, MD Division of Dermatopathology, Department of Dermatology, Warren Alpert Medical School of Brown University, Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903, USA Tel: +1 401 444 7137 Fax: +1 401 444 7105 e-mail: [email protected] Accepted for publication February 8, 2014
papules on the right inferior areola. Her past medical history was negative for previous dermatologic or systemic diseases and she denied any history of prior trauma to the affected area. Family history was negative for any similar lesions. Physical examination revealed multiple slightly firm, non-tender, white 2–4 mm papules arranged in a 3.2 × 0.8 cm linear cluster and distributed unilaterally on the right inferior areola (Fig. 1A). The remainder of the skin examination was normal. An excision of the lesion was performed (Fig. 1B). Sections stained with hematoxylin & eosin appeared normal (Fig. 2A). Weigert’s resorcin-fuchsin stain revealed the absence of elastic fibers extending from the papillary dermis to the upper reticular dermis (Fig. 2B) in lesional skin as compared to unaffected
519
Wang et al. A
B
Fig. 1. Right areola shows a linear cluster of white papules (A); there is well-healed surgical incision 4 months following excision (B).
tissue at the apices of the excision specimen (Fig. 2C). Sparse fragmented elastic fibers were noted in the deep reticular dermis (Fig. 2D). There has been no recurrence 5 years post-operatively. Discussion Nevus anelasticus typically presents as multiple flat white, skin-colored or pink-to-red 1–5 mm perifollicular papules, which are asymmetrically distributed over the chest and arms. These lesions may progress slowly over years. Routinely-stained sections usually appear normal. Elastic tissue staining may show the loss of elastic fibers and the fragmentation of residual elastic fibers in the papillary and upper reticular dermis without significant changes in the arrangement or size of collagen bundles1,4 . The clinical differential diagnosis for nevus anelasticus includes eruptive collagenoma and papular elastorrhexis. The histopathologic differential diagnosis includes anetoderma and mid-dermal elastolysis (Table 1). All of these disorders have a slight predominance for females and tend to appear during adolescence to young adulthood, with the exception of eruptive collagenoma, which has no age predilection. Eruptive collagenoma, classified as a connective tissue nevus, presents with an acute onset of multiple asymptomatic skin-colored sclerotic papules distributed symmetrically on the trunk and arms5 . Routine staining shows thick, loosely arranged collagen fibers, which distinguishes this entity from the other differential diagnoses. Elastic tissue stains may show decreased6 , degenerated7 or absence of8,9 elastic fibers throughout the dermis. Papular elastorrhexis most commonly presents as multiple discrete asymptomatic, non-follicular 1–5 mm flat, firm, monomorphic white-to-yellow papules, which are scattered on the trunk, the upper extremities and thighs10 . Routine staining may show a superficial and deep perivascular lymphohistiocytic infiltrate11 . Elastic tissue stain reveals thinned, fragmented or nearly complete loss of elastic fibers in the
520
reticular dermis4,11,12 . The arrangement of collagen fibers may vary from normal to homogenized and condensed9 . It was previously suggested that perhaps nevus anelasticus and eruptive collagenomas should be considered variants of papular elastorrhexis13 . However, given the unilateral distribution of nevus anelasticus along with the histopathological absence of elastic fibers from both the papillary and upper reticular dermis with sparse deep dermal elastic fiber fragments, we believe this particular case supports the argument that nevus anelasticus is a distinct entity. The histopathologic differential diagnosis includes anetoderma, an elastic tissue disorder characterized by round to oval, skin-colored or white-to-blue, flaccid, well-circumscribed 0.5–2 cm papules or plaques of slack skin, which may herniate inward on palpation14 . These are most commonly located symmetrically on the trunk, upper arms and thighs14 . Routine staining may appear normal or may show a predominantly perivascular mixed infiltrate with or without multinucleated giant cells showing elastophagocytosis.15,16 Elastic tissue staining may show variable patterns of loss and fragmentation of dermal elastic fibers, such as in the upper and lower reticular dermis or throughout the dermis17 . Mid-dermal elastolysis is an acquired elastic tissue disorder, which often presents as well-demarcated areas of perifollicular papules or fine wrinkling with inflammatory skin changes such as reticular erythema18 on the trunk or proximal extremities. Whereas routinely-stained sections may show similar patterns to those described in inflammatory anetoderma, it is histopathologically distinguished by the absence of elastic fibers exclusively in the mid-dermis18 . The classification of nevus anelasticus has been a topic of ongoing debate since its introduction in 1921. Lewandowsky initially proposed the term naevus elasticus regionis mammariae after describing three cases that clinically presented with acquired non-evolving white-to-yellow, round, firm, clustered perifollicular papules on the anterior chest2 . Histopathologically, these lesions were characterized by a normal appearance in hematoxylin & eosin and von Gieson stains along with degenerated and absent elastic fibers in the papillary and upper reticular dermis with Unna Tanzer orcein stains2 . The term nevus elasticus was subsequently coined to describe a connective tissue nevus that primarily involved an abnormality in elastic tissue composition19 . Subsequently, Staricco and Mehregan redefined nevus elasticus as a connective tissue nevus with increased elastic tissue, and argued for limiting the usage of nevus anelasticus
Nevus anelasticus classification A
B
2b
C
2c
D
Fig. 2. (A) In a hematoxylin/eosin stain, there is normal-appearing collagen (×10). B and C) Weigert’s resorcin-fuchsin stain shows (B) absence of elastic fibers in the papillary, upper and mid-reticular dermis (×20) compared to (C) normal elastic fiber pattern in the papillary dermis (×20). D). Weigert’s resorcin-fuchsin stain shows sparse fragmented elastic fibers (arrow) in the deep reticular dermis (×40).
to connective tissue nevus with decreased elastic tissue20 . Meanwhile, over the past several decades, the definition of a connective tissue nevus has evolved to represent a hamartoma with an accumulation of one of the components of the dermis: collagen, elastic tissue or glycosaminoglycans19 . In the past, it had been proposed that the classification of connective tissue nevi should be based on the portion of the dermis affected, the reticular vs. the adventitial, and not on the actual concentration of dermal components21 . Nevus anelasticus historically falls under the category of ‘nevi of reticular connective tissue’ based on the location of dermal-content irregularity. ‘Nevi of reticular connective tissue’ has been described as ‘‘a circumscribed, intradermal nodule, sparse of cells and endophytic or exophytic upon a broad base’’21 . However, nevus anelasticus does not match this pathologic description, and thus this classification system would not suffice. It has also been suggested that nevus anelasticus would be better categorized as an elastic tissue disorder variant rather than a connective tissue
nevus22 as nevus anelasticus is histopathologically characterized by a decrease in elastic tissue relative to a normal amount of collagen. Previously, certain collagenomas have been shown to have patterns of decreased elastic fibers, but was later suggested to result from a dilutional effect because of alterations in the arrangement of collagen bundles in the dermis rather than a true decrease in elastic fibers4 . However, nevus anelasticus is generally believed to be a true elastic fiber abnormality and not secondary to a dilutional affect. Thus, Lewis et al. proposed that nevus anelasticus would be better classified as an elastic tissue disorder22 . Both the rarity and ambiguous nosology of nevus anelasticus have made it difficult to identify, classify and understand this disorder. To our knowledge, only two other reports of nevus anelasticus have been previously published in the English literature2,20 . The pathogenesis, however, remains unknown. While nevus anelasticus is clinically nevoid in appearance, based upon its histopathologic features, we believe it would be more appropriately categorized as a distinct elastic tissue disorder.
521
Wang et al. Table 1. Clinical and histopathologic differential for nevus anelasticus Clinical differential diagnosis
Histopathologic differential diagnosis
Eruptive
Papular
Nevus anelasticus
collagenoma
elastorrhexis
Anetoderma
elastolysis
Clinical morphology
Multiple flat white-toskin-toned or pink-red colored 1–5 mm perifollicular papules
Multiple asymptomatic skin-colored sclerotic papules
Multiple discrete asymptomatic, non-follicular 1–5 mm flat, firm, monomorphic white-to-yellow papules
Oval, skin-colored or white-to-blue, flaccid, wellcircumscribed 0.5–2 cm papules or plaques of slack skin
Well-demarcated perifollicular papules or areas of fine wrinkling with inflammatory skin changes
Distribution
Chest, arms
Trunk, arms
Trunk, the upper extremities and thighs
Trunk, upper arms and thighs
Proximal extremities and trunks
Symmetrical?
No
Yes
Yes
Yes
Yes
Hematoxylin & eosin stain
Normal
Thick, loosely arranged collagen fibers
Superficial and deep perivascular lymphohistiocytic infiltrate
Normal without signs of inflammation, or may show a predominantly perivascular mixed infiltrate
Normal without signs of inflammation, or may show a predominantly perivascular mixed infiltrate
Elastic tissue stain
Loss of elastic fibers and fragmentation of residual elastic fibers in the papillary and upper reticular dermis. No changes in the arrangement or size of collagen bundles
Decreased, degenerated, or absent elastic fibers throughout the dermis
Variable patterns of Thinned, fragmented, loss and or nearly complete fragmentation of loss of elastic fibers dermal elastic in the reticular fibers, such as in dermis. Collagen upper and lower fibers may vary from reticular dermis or normal to throughout the homogenized and dermis condensed
Acknowledgements Wang AR, Jagdeo J, Bercovitch L, RobinsonBostom L. ‘Nevus Anelasticus: a rare case of uncertain classification’, presented at Gross & Micro
Mid-dermal
Absence of elastic fibers exclusively in the mid-dermis
Symposium, American Academy of Dermatology Annual Meeting 4–8 February, 2011, New Orleans, LA. The authors would like to acknowledge the assistance of Florian Froehlich in translating reference 2 by Lewandowsky.
References 1. Crivellato E. Disseminated nevus anelasticus. Int J Dermatol 1986; 25: 171. 2. Lewandowsky F. Uber einen eigentumlichen naevus der brustgegend. Arch Derm Syph 1921; 131: 90. 3. Del Pozo J, Martinez W, Sacristan F, Fernandez-Jorge B, Fonseca E. Papular elastorrhexis, a distinctive entity? Am J Dermatopathol 2008; 30: 188. 4. Sears JK, Stone MS, Argenyi Z. Papular elastorrhexis: a variant of connective tissue nevus. J Am Acad Dermatol 1988; 19: 409. 5. Henderson RR, Wheeler CE, Abele DC. Familial cutaneous collagenoma. Arch Dermatol 1968; 98: 23.
522
6. Amaya M, Okubo Y, Koga M. A case of eruptive collagenoma localized on the neck and shoulders. J Dermatol 2002; 29: 79. 7. Lee MW, Choi JH, Sung KJ, Moon KC, Koh JK. A case of eruptive collagenoma. Pediatr Dermatol 2002; 19: 565. 8. Smith LR, Bernstein BD. Eruptive collagenoma. Arch Dermatol 1978; 114: 1710. 9. Ryder HF, Antaya RJ. Nevus anelasticus, papular elastorrhexis, and eruptive collagenoma: clinically similar entities with focal absence of elastic fibers in childhood. Pediatr Dermatol 2005; 22: 153. 10. Buechner SA, Itin P. Papular elastorrhexi: report of five cases. Dermatology 2002; 205: 198.
11. Bordas X, Ferrandiz C, Ribera M, Galofre E. Papular elastorrhexis: a variety of nevus anelasticus? Arch Dermatol 1987; 123: 433. 12. Schirren H, Schirren CG, Stolz W, et al. Papular elastorrhexis: a variant of dermatofibrosis lenticularis disseminata (Buschke–Ollendorff syndrome). Dermatology 1994; 189: 368. 13. Choonhakarn C, Jiratattanapochai K. Papular elastorrhexis: a distinct variant of connective tissue nevi or an incomplete form of BuschkeOllendorff syndrome? Clin Exp Dermatol 2002; 27: 454. 14. Venencie PY, Winkelmann RK, Moore BA. Anetoderma: clinical findings, associations, and long term follow-up evaluations. Arch Dermatol 1984; 120: 1032.
Nevus anelasticus classification 15. Kossard S, Kronman KR, Dicken CH, Schroeter AL. Inflammatory macular atrophy: immunofluorescent and ultrastructural findings. J Am Acad Dermatol 1979; 1: 325. 16. Zaki I, Scerri L, Nelson H. Primary anetoderma: phagocytosis of elastic fibres by macrophages. Clin Exp Dermatol 1994; 19: 388. 17. Oikarinen AI, Palatsi R, Adomian GE, Oikarinen H, Clark JG, Uitto J. Anetoderma: biochemical and ultrastructural demonstration of an elastin defect in the skin of
three patients. J Am Acad Dermatol 1984; 11: 64. 18. Shelley WB, Wood MG. Wrinkles due to idiopathic loss of mid-dermal elastic tissue. Br J Dermatol 1977; 97: 441. 19. Uitto J, Santa Cruz DJ, Eisen AZ. Connective tissue nevi of the skin: clinical, genetic, and histopathologic classification of hamartomas of the collagen, elastin, and proteoglycan type.
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