Plaque-type blue nevus combined with lentigo (nevus spilus) Three cases of plaque-type blue nevus accompanied with lentigo-like changes were reported. The combination of blue nevus and lentigo (nevus spilus) is a new type of "combined nevus", but it belongs to the second type of Kawamura's atypical blue nevus. This combination is unlikely to be rare, not only in plaque-type, but also in common type blue nevus, and to be comparable with the findings of such dermal melanocytosis as nevus of Ota. Histologically, cellular blue nevus was also observed in areas of Case 1. Ishibashi A, Kimura K, Kukita A. Plaque-type blue nevus combined with lentigo (nevus spilus). J Cutan Pathol 1990: 17: 241245.
Among cases of blue nevus of the skin, the following types are usually seen: common, showing generally solitary, but rarely multiple, nodules; cellular, showing larger nodules; and combined, showing blue nevus combined with nevus cell nevus. As a rare manifestation, the plaque type, showing a plaque composed of an aggregation of many blue macules and/or papules, is also found. This paper reports three cases of plaque-type blue nevus accompanied by nevus spilus-like brown macules.
A. Ishihashi, K. Kimura, A. Kukita Department of Dermatology, National Defense Medical College, Tokorozawa, Japan
Akira Ishibashi, Department of Dermatology, National Defense Medical College, 3-2, Namiki, Tokorozawa, Saitama 359, Japan Accepted January 15, 1990
Case reports Case 1. A 25-year-old woman with a pigmented lesion present since birth in the left chest wall, visited our department in October 1985. On examination, a speckled fusiform pigmented plaque measuring 15 X 4 cm was found in the area from the left shoulder to the breast. This speckled plaque was composed of multiple deep-blue colored papules, with an underlying aggregation of numerous blue macules that varied slightly in shade. In addition, an irregularly
Fig. 1. Speckled fusiform plaque composed of numerous deep blue macules, papules ahd small brown patches (Gase 1). Hi CiUiuiCdiis I'alliology
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Ishibashi et al. Fig. 2. Lentigo-like changes in the epidermis (Case 1). (H&E X200).
shaped brown patch, consisting of an aggregation of small brown macules, mostly overlapped with the blue lesion, with some parts that did not overlap (Fig. 1). The overlapped area was bluish brown, and the non-overlapped areas were blue or brown.
Histological examination of the resected specimen revealed findings of common blue nevus in the der-
Fig. 3. Solid aggregate of bipolar meianocytes in the vicinity of pilosebaceous organ (Case 1) (H&E X25).
Fig. 4. Speckled pigmented lesion composed of small blue and brown macules in Case 2.
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Plaque-type blue nevus combined witb lentigo
Histological sections of the resected specimen revealed findings of common blue nevus in the dermis and lentigo-like findings in the epidermis (Fig. 5). These findings, however, were less estensive than those in Case 1, while some elongation of rete ridges was equally observed. Dermal meianocytes in the dermis were often located in areas surrounding small blood vessels, skin appendages, and peripheral nerve bundles. Case 3. A lS-year-old boy with a pigmented lesion, present since birth, on the right shoulder, visited our department in March 1987. The lesion, which originally had a blue tone, had for about 1 year shown an enhanced black-brown tone and slight elevation. Upon examination, a fusiform, pigmented plaque measuring 7 X 2 cm was observed on the right shoulder; the lesion was slightly elevated, showing a gradual increase in height from the peripheral part toward the center. A brown patch with irregular borders lay over speckled blue macules. The area of the blue macules was greater, forming a blue margin around the blue-brown patch, but in sonie areas the brown patch protruded. Some of the punctate blue macules showed a slight papular elevation. In a neighboring area, separate from this lesion, there
/n^. 5. Lenligo-like findings in the epidermis, and those of blue nevus in the dermis (Case 2) (H&E X50).
mis, and those of lentigo (nevus spilus) in the epidermis, that is, a slight elongation of rete ridges and an increase in the number of meianocytes and melanin in the epidermal basal layer, particularly in the elongated rete ridges (Fig. 2). Dermal meianocytes composing the blue nevus were often distributed along pilosebaceous organs and sweat glands, sometimes forming a sharply demarcated mass in the vicinity of the hair follicle or the sebaceous gland (Fig. 3). In a very limited area, cellular blue nevuslike foci, with closely aggregated cells having a round nucleus and a little melanin, were found. In these foci, cells with abundant melanin in the cytoplasms were frequently present at the periphery of a mass. Case 2. A 16-year-old girl with a pigmented lesion on the left thigh, which had probably existed since infancy, visited our department in March 1979. Upon examination, a fusiform plaque measuring 8 X 2 cm was found on the lateral side of the left thigh. Multiple punctate blue macules were present in a mottled pattern on speckled brown patches. (Fig. 4).
Fig. 6. Fusiform, slightly elevated, pigmented plaque in Case 3. An irregular-shaped brown patch lay over blue macules. A cafe-au-lait spot-like brown-colored lesion is also seen in a neighboring area.
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Isbibasbi et al.
f^z^. 7. Slightly acanthotic epidermis accompanied by an elongation of rete ridges and an increase of meianocytes in the basal layer, and numerous bipolar dermal meianocytes among collagen bundles of the middle dermis (Case 3) (H&E X5O).
was a cafe-au-lait, spot-like brown patch (Fig. 6). However, there were no other findings suggestive of neurofibromatosis. Histological features of the resected specimen were similar to those in Case 2, but more marked. Greater numbers of dermal meianocytes were present from the papillary layer to the deep dermis, forming a distinct aggregation in the center, thus constituting the features of blue nevus. The rete ridges were somewhat elongated. Co-existing melanophages, as well as epidermal meianocytes, were more numerous than in Case 2 (Fig. 7). Comment The three cases reported here were plaque-type blue nevus, accompanied by nevus spilus-like brown patches within the lesion or partly protruding from it. Histologically, the blue macules or blue papules denoted findings of common blue nevus, and moreover, there were findings of lentigo in the epidermis, i.e., an elongation of rete ridges and increased mela244
nin and meianocytes in the epidermal basal layer. Although the meianocytes in the epidermis were aggregated in some areas (particularly in Case 1), no nevus cell nests were observed. Therefore, these cases do not fall into the category of "combined nevus", in which blue nevus is combined with junctional, compound, and intradermal nevus cell nevus. Kawamura (1) reported a case of blue nevus accompanied by nevus spilus under the term "atypical blue nevus", and stated that atypical blue nevus could be classified histologically into the following types: 1) a combination in which ordinary pigmented nevus cells are present directly beneath the epidermis, and fusiform blue nevus cells are present in a deeper layer of the cutis; 2) a combination of increased meianocytes in the epidermis (i.e. nevus spilus) and blue nevus cells in the dermis; 3) a combination of blue nevus apd a proliferative change (nevus change) in tissues other than meianocytes or nevus cells, such as fibromatous or myomatous change. According to his concept, our cases are considered to belong to the second type of "atypical blue nevus". In his textbook, Montgomery (2) noted that lentigo-like changes were histologically present in several cases of blue nevus clinically showing typical blue nodules. However, there were no descriptions of any such combined cases in recent texts by Lever et al. (3), Okun et al. (4) and others. In Japan, several cases of Type 2 atypical blue nevus have been reported, and our 3 cases of plaque-type blue nevus were all accompanied by nevus spiluslike lesions. We speculate that it is not very rare for blue nevus to be accompanied by lentigo- or nevus spilus-like lesions, or at least that an association with nevus spilus-like lesions is frequent among Japanese cases of plaque-type blue nevus. This condition is comparable to nevus of Ota and of Ito, characterized by blue macules or a combination of blue macules and brown patches. However, from a histological aspect, the brown patch in Type 2 atypical blue nevus shows features indicative of lentigo, whereas the histological features of the brown patch in the nevus of Ota or of Ito are characterized by the presence of dermal meianocytes in the dermal papillary layer, suggesting a general difference between the two, although Tanino (5) and Kawamura (6) have reported that an increase in meianocytes or findings of nevus spilus were also present in the epidermis in nevus of Ota. References 1. Kawamura T. Atypical blue nevus. Arch Dermatol 1950: 62: 395. 2. Montgomery H. Blue nevus. Dermatopathology. New York: Harper & Row, 1967: 1184.
Plaque-type blue nevus combined witb lentigo 3. Lever WE, Schaumburg-Lever C. Blue nevus. Histopathology of the skin. Philadelphia: Lippincott, 1983: 700. 4. Okun MR, Edelstein LM, Eisher BK. Blue nevus. Cross and microscopic pathology of the skin. Canton, U.S.A.: Dematopathology Eoundation Press, 1988: 1172.
5. Tanino H. On nevus fuscocaeruleus ophthalmomaxillaris (Ota). Jpn J Dermatol 1939: 46: 435, 1940: 47: 181 (in Japanese). 6. Kawamura T. Naevus fuscocaeruleus ophthalmomaxillaris Ota. Nippon Hifuka Zensho. Vol VH-2. Naevus and phacomatosis. Tokyo: Kanehara Publishers, 1957: 136 (in Japa-
245
Among cases of blue nevus of the skin, the following types are usually seen: common, showing generally solitary, but rarely multiple, nodules; cellular, showing larger nodules; and combined, showing blue nevus combined with nevus cell nevus. As a rare manifestation, the plaque type, showing a plaque composed of an aggregation of many blue macules and/or papules, is also found. This paper reports three cases of plaque-type blue nevus accompanied by nevus spilus-like brown macules.
A. Ishihashi, K. Kimura, A. Kukita Department of Dermatology, National Defense Medical College, Tokorozawa, Japan
Akira Ishibashi, Department of Dermatology, National Defense Medical College, 3-2, Namiki, Tokorozawa, Saitama 359, Japan Accepted January 15, 1990
Case reports Case 1. A 25-year-old woman with a pigmented lesion present since birth in the left chest wall, visited our department in October 1985. On examination, a speckled fusiform pigmented plaque measuring 15 X 4 cm was found in the area from the left shoulder to the breast. This speckled plaque was composed of multiple deep-blue colored papules, with an underlying aggregation of numerous blue macules that varied slightly in shade. In addition, an irregularly
Fig. 1. Speckled fusiform plaque composed of numerous deep blue macules, papules ahd small brown patches (Gase 1). Hi CiUiuiCdiis I'alliology
241
Ishibashi et al. Fig. 2. Lentigo-like changes in the epidermis (Case 1). (H&E X200).
shaped brown patch, consisting of an aggregation of small brown macules, mostly overlapped with the blue lesion, with some parts that did not overlap (Fig. 1). The overlapped area was bluish brown, and the non-overlapped areas were blue or brown.
Histological examination of the resected specimen revealed findings of common blue nevus in the der-
Fig. 3. Solid aggregate of bipolar meianocytes in the vicinity of pilosebaceous organ (Case 1) (H&E X25).
Fig. 4. Speckled pigmented lesion composed of small blue and brown macules in Case 2.
242
Plaque-type blue nevus combined witb lentigo
Histological sections of the resected specimen revealed findings of common blue nevus in the dermis and lentigo-like findings in the epidermis (Fig. 5). These findings, however, were less estensive than those in Case 1, while some elongation of rete ridges was equally observed. Dermal meianocytes in the dermis were often located in areas surrounding small blood vessels, skin appendages, and peripheral nerve bundles. Case 3. A lS-year-old boy with a pigmented lesion, present since birth, on the right shoulder, visited our department in March 1987. The lesion, which originally had a blue tone, had for about 1 year shown an enhanced black-brown tone and slight elevation. Upon examination, a fusiform, pigmented plaque measuring 7 X 2 cm was observed on the right shoulder; the lesion was slightly elevated, showing a gradual increase in height from the peripheral part toward the center. A brown patch with irregular borders lay over speckled blue macules. The area of the blue macules was greater, forming a blue margin around the blue-brown patch, but in sonie areas the brown patch protruded. Some of the punctate blue macules showed a slight papular elevation. In a neighboring area, separate from this lesion, there
/n^. 5. Lenligo-like findings in the epidermis, and those of blue nevus in the dermis (Case 2) (H&E X50).
mis, and those of lentigo (nevus spilus) in the epidermis, that is, a slight elongation of rete ridges and an increase in the number of meianocytes and melanin in the epidermal basal layer, particularly in the elongated rete ridges (Fig. 2). Dermal meianocytes composing the blue nevus were often distributed along pilosebaceous organs and sweat glands, sometimes forming a sharply demarcated mass in the vicinity of the hair follicle or the sebaceous gland (Fig. 3). In a very limited area, cellular blue nevuslike foci, with closely aggregated cells having a round nucleus and a little melanin, were found. In these foci, cells with abundant melanin in the cytoplasms were frequently present at the periphery of a mass. Case 2. A 16-year-old girl with a pigmented lesion on the left thigh, which had probably existed since infancy, visited our department in March 1979. Upon examination, a fusiform plaque measuring 8 X 2 cm was found on the lateral side of the left thigh. Multiple punctate blue macules were present in a mottled pattern on speckled brown patches. (Fig. 4).
Fig. 6. Fusiform, slightly elevated, pigmented plaque in Case 3. An irregular-shaped brown patch lay over blue macules. A cafe-au-lait spot-like brown-colored lesion is also seen in a neighboring area.
243
Isbibasbi et al.
f^z^. 7. Slightly acanthotic epidermis accompanied by an elongation of rete ridges and an increase of meianocytes in the basal layer, and numerous bipolar dermal meianocytes among collagen bundles of the middle dermis (Case 3) (H&E X5O).
was a cafe-au-lait, spot-like brown patch (Fig. 6). However, there were no other findings suggestive of neurofibromatosis. Histological features of the resected specimen were similar to those in Case 2, but more marked. Greater numbers of dermal meianocytes were present from the papillary layer to the deep dermis, forming a distinct aggregation in the center, thus constituting the features of blue nevus. The rete ridges were somewhat elongated. Co-existing melanophages, as well as epidermal meianocytes, were more numerous than in Case 2 (Fig. 7). Comment The three cases reported here were plaque-type blue nevus, accompanied by nevus spilus-like brown patches within the lesion or partly protruding from it. Histologically, the blue macules or blue papules denoted findings of common blue nevus, and moreover, there were findings of lentigo in the epidermis, i.e., an elongation of rete ridges and increased mela244
nin and meianocytes in the epidermal basal layer. Although the meianocytes in the epidermis were aggregated in some areas (particularly in Case 1), no nevus cell nests were observed. Therefore, these cases do not fall into the category of "combined nevus", in which blue nevus is combined with junctional, compound, and intradermal nevus cell nevus. Kawamura (1) reported a case of blue nevus accompanied by nevus spilus under the term "atypical blue nevus", and stated that atypical blue nevus could be classified histologically into the following types: 1) a combination in which ordinary pigmented nevus cells are present directly beneath the epidermis, and fusiform blue nevus cells are present in a deeper layer of the cutis; 2) a combination of increased meianocytes in the epidermis (i.e. nevus spilus) and blue nevus cells in the dermis; 3) a combination of blue nevus apd a proliferative change (nevus change) in tissues other than meianocytes or nevus cells, such as fibromatous or myomatous change. According to his concept, our cases are considered to belong to the second type of "atypical blue nevus". In his textbook, Montgomery (2) noted that lentigo-like changes were histologically present in several cases of blue nevus clinically showing typical blue nodules. However, there were no descriptions of any such combined cases in recent texts by Lever et al. (3), Okun et al. (4) and others. In Japan, several cases of Type 2 atypical blue nevus have been reported, and our 3 cases of plaque-type blue nevus were all accompanied by nevus spiluslike lesions. We speculate that it is not very rare for blue nevus to be accompanied by lentigo- or nevus spilus-like lesions, or at least that an association with nevus spilus-like lesions is frequent among Japanese cases of plaque-type blue nevus. This condition is comparable to nevus of Ota and of Ito, characterized by blue macules or a combination of blue macules and brown patches. However, from a histological aspect, the brown patch in Type 2 atypical blue nevus shows features indicative of lentigo, whereas the histological features of the brown patch in the nevus of Ota or of Ito are characterized by the presence of dermal meianocytes in the dermal papillary layer, suggesting a general difference between the two, although Tanino (5) and Kawamura (6) have reported that an increase in meianocytes or findings of nevus spilus were also present in the epidermis in nevus of Ota. References 1. Kawamura T. Atypical blue nevus. Arch Dermatol 1950: 62: 395. 2. Montgomery H. Blue nevus. Dermatopathology. New York: Harper & Row, 1967: 1184.
Plaque-type blue nevus combined witb lentigo 3. Lever WE, Schaumburg-Lever C. Blue nevus. Histopathology of the skin. Philadelphia: Lippincott, 1983: 700. 4. Okun MR, Edelstein LM, Eisher BK. Blue nevus. Cross and microscopic pathology of the skin. Canton, U.S.A.: Dematopathology Eoundation Press, 1988: 1172.
5. Tanino H. On nevus fuscocaeruleus ophthalmomaxillaris (Ota). Jpn J Dermatol 1939: 46: 435, 1940: 47: 181 (in Japanese). 6. Kawamura T. Naevus fuscocaeruleus ophthalmomaxillaris Ota. Nippon Hifuka Zensho. Vol VH-2. Naevus and phacomatosis. Tokyo: Kanehara Publishers, 1957: 136 (in Japa-
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