Report
VOLAR MELANOTIC MACULES THOMAS A. CHAPEL, M.D., RO BERT M . TAYLOR, M .D . AND HERMANN PINKUS, M .D .
From the Department of Derm atology and Syphilo /ogy, Way ne State Universit y Schoo l of M edicine, D etroit, Michigan
ABSTRACT: Asymptoma ti c lig ht brown or tannish-gray m acu/es are seen an palms andlor so /es of black patients, and occs io nally an the vo lar surfa ces of w hites. Th ey ma y be mistaken far lesions of secondary syphilis or oth er p ostinflammatory h yp erpigmented derm atoses. Histologic examination o f 14 sp ec im ens obtained at necropsy showed purel y cpiderm al hyperpigmentation o f al/ epidermal layers; or (3) melanin restrie/ed to large dendritic m elanocytes without appreciab le transfer to keratin ocytes. Th e number of me/anocytes was not significa ntly increased, and w ith one exceptinn, th ere w ere no nevus ce lls. Th ese vo lar me/anotie maculcs have close clin ica / and histo log ic resemblance /o me/anotie macules observed nccas ionally on th e vermillion arca nf th e lips.
Evenly pigm ented light tan or tannish-gray ma c ul es o cc ur frequently on th e palms and/or so les of black patients but similar spots are unco mmon in white patients. We recently observed volar macules in 87 of 145 (60%) adult black patients seen in the affiliated outpatient c linics of Wayne State University. These maculcs vary in size from a few millimeters to two or more centimeters in diameter. They have a variabl e co nfiguration and outline, but are frequently ovoid with rather sharp regul ar borders (Fig. l) . In genSuppu rted by the Detru it Generai H ospital Research Curpurati on. Address fur reprint s: Thu ma s A. Chapel, M .D ., Department u f Derm atolugy and Syphilo lugy, Way ne State University, 540 E. Canfield Avenue, Detru it , MI 48 20 l. 00 11-9059179 / 0400/ 0222 / $00.70
eral , pigmented macular lesions on palms and soles may be junctional nevi, ephelides, postinflamm atory hyperpigmentation, or lentiginous malignant melanoma. Because we were unable to find any definitive histologic description of these multiple, asymptomatic macules in the literature, we elected to .remove severa! from the volar skin of patients at autopsy, the histology of which forms the basi s of this report.
Materials and Methods Punch specimens, 4 mm in diameter, were taken from pigmented macules on the volar surfaces of 15 cadavers at necropsy. The patients ranged in age from 24 to 83 years. Eleven were black, four white, seven women and eight men. Two of the 15 specimens were taken from the palm and the remainder from the so le. Ali of the spec imens were fixed in formali n, embedded in paraffin , and 1O mi c ron sections were stain ed with both hematoxyli n-eosin and acid orcein and Giemsa solution. In addition, one 4-mm punch biopsy of a typical pigmented palmar macule was taken from a 61-year-old black volunteer and stained with Dopa so lution for an accurate melanocyte count.
Results O ne of the 15 lesions examined hi stologica lly was an intradermal nevus ce li nevus. None of the rest co ntained any nevus ce ll s. Ali exhibited purely epid ermal hyperpigmentation and in some cases a few pi gmented macrophages in the derrni s. The generai configuratio n of the epidermi s was fairly normal and exhibited the usual fea-
© lnternation al 222
Soc iety o f Tropi ca l Derm ato logy, lnc.
No. 3
VOLAR MELANOTIC MACULES
tures of ridged volar skin with regularly spaced eccrine ducts (Fig. 2). The sweat duct ridges were unusually broad and possessed a squared-off horizontal lower border. No apparent increase in number of junctional melanocytes was evident on routine staining of specimens. The distribution of melanin granules exhibited three distinct types. The most common type showed a very dark pigmentation of the basai keratinocytes (basai type B) with barely any melanin visible in the subrabasal layers. Melanocytes were inconspicuous (Fig. 3). Hyperpigmentation was most pronounced on the lower part of the sweat duct ridges. Another group showed melanin granules in ali epidermallayers (epidermal type E) including basai cells, prickle cells, and corneocytes (Fig. 4). In the least common type, melanin granules were present in large and highly dendritic melanocytes (dendritic type D) while no or few pigmented granules were seen in keratinocytes (Fig. 5). Some of the specimens represented pure types B, D, or E, while in others, two or ali three types were mixed in one lesion. Melanin was present in the B, D, andE types of distribution in the Dopa-stained specimen but there was no appreciable increase in the number of junctional melanocytes.
Chape/, et al.
Fig. l .
223
Typical melanotic macules on the palm.
ti?n and need not be considered here in dtfferential diagnosis. Nevus spilus in the classica! sense design_ates congenita! pigmented spots of variable stze containing approximately norma! numb~rs of me_lanocytes and increased epidermal ptgmentatton of mild degree.t An acquired an~ progressive variant has recently been des~nbed as_cribriform and zosteriform hyperptgmentatton.2 The lesions in these and some
Discussion Circumscribed epidermal pigmentation is encountere d in human skin in freckles (ephelides), lentigines, and nevi spili (cafe au lait spots). Ephelides have somewhat fewer and larger active melanocytes than the surrounding skin, their keratinocytes contain more mela n in granules, and their clinica! and histologic appearance is influenced by sunlight. Lentigines are subdivided into the simplex (juvenile), senile, and malignant types. The juvenile and senile types show excess numbers of m~lanocytes in combination with accentuated rete ridges and peg-like basai buds. The keratinocytes contain melanin granules and, in lentigo simplex, may exhibit the highest degree of keratinocyte pigmentation seen anywhere in human skin . Lentigo maligna (Hutchinson 's melanotic freckle) has atypical melanocytic prolifera-
Fig. 2. Diagram of volar skin, reprodu ced with permi SSIOn and alt erations from F. Pinku s, Die Normale Anatomie der Haut, Fi g. 280. In : Jadassohn's H andbuch der H aut-und Geschlechtskrankheiten, vol. 1, part 1 Berlm , Spnnger-Verlag, 1927. Superfi cial rid ges and furrows and deep fol_ d s of the epidermi s have been give n a vanety o f des1gnat1on s m the literature. A = Dermatoglyphlc nd ge or cri sta ~ upe rfici a li s. B = Dermatoglyphi c ~rrow or sulcus supert1 c1al1 s. C = Ecc rine swea t pare. D ~ Sweat .duet nd ge, glandular fold , or cri sta profunda mtermed1 a. E = Limitin g dee p rid ge, furro w fold, or cri sta profund a l1m1tans.
224
INTERNATIONAL JOURNAL OF DERMATOLOGY
Aprii 1979
Vol. 18
Fi g. 3. Top, volar melanoti c macule, hi stologi c type B {Acid orce in and Giemsa x 60) . Fig. 4. Bott om , volar melanoti c mac ul e, mixed type, type E prevails as manifested by melanin in c lusions i n horny layer. A t right sid e of pi c tur e, type E merges into type B; at left sid e, dendritic ce lls of type D are present {Ac id orce in and Giemsa x 60) .
other reported cases are histologically similar, but clinically different because they are restricted to one or a few asymmetrical areas of body skin in contrast to the usually symmetrical volar pigmented macules.3 - 8 There exists, however, in another specialized part of the skin surface, one condition that seems to correspond rather closely to the macules under discussion. This condition is the pigmented macule on ~he vermillion of the lips which to our knowledge has been investigated only twice before under
the name solitary labiallentigo 9 and by labial melanotic macule, 10 the term we prefer. Both publications stress hyperpigmentation of the basai layer. The latter authors point out that the pigmentation is concentrated along the lower half of the rete ridges and that the suprapapillary epithelium is rarely pigmented. Neither publication 9 • 10 mentions the other two types of mel an in di stribution seen in the volar macules. Their photomicrographs show flat and square lower borders of rete ridges.
No. 3
VOLAR MELANOTIC MACULES
We there fore believ e that the labia l melan otic macules and the volar melan otic macules are closely related . lt remains to explain the mechanism of these hyperpigmentations. In as much as the numb er of melanocytes is not obvio usly increased, one has a postulate melan ocytic hyperfunction . However, ordina rily, when melan ocytic function is increased, either temporarily after irradiation, or genet ically in black skin, the "epidermal melan in unit" results in proportionate hyper pigme ntatio n of melanocytes and ali keratinocytes. lt is difficu lt to explain how in labial and the most comm on type of volar macules melan in granules are concentrated in the basallayers andar e not carri ed outwa rd with the maturing divisio n products into the spinous and keratinized layers . lt is even more intrigu ing to see in some lesions that this latter process is ìntact in sharply limite d colum nar foci while to the right and left, melanin is not carried upward. lt seems most likely that the latter phenomenon is due to some biolog ie dysfunction in the keratinocytes rather than in the melanocytes. The third (D) type seems to represent complete dissociation of the epidermal melan in unit. Almost no melanin granules are transferred into keratinocytes. This pigment block is ordina rily seen in acute or subacute inflamm atory condi tions and appears to be due to the ·i nabili ty of the diseased keratinocytes to accept melanin granules, which therefore accum ulate in the engorged dendr ites of melanocytes. 11 • 12 There is, however, no evidence of inflam matio n in the volar macules. One other and possibly homologous condi tion exists in the skin of the foot pads of black rats . This skin usual ly is mode rately pigmente d on gross inspe ction. Histo logic exam inatio n (Pink us , unpu blishe d communic ation) often shows large and deeply pigme nted dendri1ic melan ocyte s and no pigment in keratinocytes. lt seems possib le that volar skin, in rat and man, has less ability to phagocytize melanosomes than other skin
l. Pinku s, H., and Mehregan, A. : A Guide To Der-
225
D Fig. 5. Volar melanotic macule, histologi c type (Acid orcein and Giemsa x 200).
2.
3.
4. 5.
6. 7. 8.
9.
l O.
11 .
area s. References
Chape/, et al.
12.
matoh istopa tholog y, 2nd ed . N ew York, Appl eton-C entury-Crofts, 1976, p. 446. Rower, J.• Carr, R., and Lown ey, E.: Progressive . cribifo rm and zosteri form hype rpigm entatio n Arch. Dermatol. 114 :98, 1978. Selmanowitz, F., and Orentre ich, N.: Tardive pattern ed pigme nt ed ma eu le s. Are h. Derma tol. l 02 :483, 1970. ' Shumate, C. A.: Pigm ented unilate ral nevus- like lentigo. Are h. Dermatol. Syphilol. 43:41 O, 1941. Becker, S. W ., and Reuter, M . j. : A familial pigm en, tary anoma ly. Arch. Dermatol. Syphilo l. 40:987 1939. Cappon D: A case of unilaterall entigines with menta l deficiency. Br. J. Dermatol. 60:371 , 1948 . M cKe lway, J. L. : Lentigo: unilate ral distribu tion.NY St. J. Med. 80 : 197, 1940. Chernosky, M .E., Anderson, D. E., Chang, J. P. et al.: Familial progressive hyperpigm entation . Arch. Dermatol. l 03 :581 , 1971. Shapiro , L., and Zegare lli, D.: The solitary labial lentigo : a clinicop atholog i c study of twe nty cases. Ora l Surg. 31 :87, 1971 . , Weathers, D., Corio, R., Crawford, R., Giansanti , J. ra! O . macule tic melano labial and Page, L.: The Surg. 42:196 , 1976. Pinkus, H., Staricco, R. , Kropp, P., and Fan , J.: The symbiosis of melanocytes and human epid ermis under norma l and abnormal conditi ons. In : Pigment Celi Biology. Edited by Gordon , M. New York, Academic Press, 1959, p. 127. Pinku s, H., and M ehregan , A.: A Guide To Der, matoh i stopat hology , 2nd ed . N ew York Appleton-Century-Crofts, 1976, p. 47 .
VOLAR MELANOTIC MACULES THOMAS A. CHAPEL, M.D., RO BERT M . TAYLOR, M .D . AND HERMANN PINKUS, M .D .
From the Department of Derm atology and Syphilo /ogy, Way ne State Universit y Schoo l of M edicine, D etroit, Michigan
ABSTRACT: Asymptoma ti c lig ht brown or tannish-gray m acu/es are seen an palms andlor so /es of black patients, and occs io nally an the vo lar surfa ces of w hites. Th ey ma y be mistaken far lesions of secondary syphilis or oth er p ostinflammatory h yp erpigmented derm atoses. Histologic examination o f 14 sp ec im ens obtained at necropsy showed purel y cpiderm al hyperpigmentation o f al/ epidermal layers; or (3) melanin restrie/ed to large dendritic m elanocytes without appreciab le transfer to keratin ocytes. Th e number of me/anocytes was not significa ntly increased, and w ith one exceptinn, th ere w ere no nevus ce lls. Th ese vo lar me/anotie maculcs have close clin ica / and histo log ic resemblance /o me/anotie macules observed nccas ionally on th e vermillion arca nf th e lips.
Evenly pigm ented light tan or tannish-gray ma c ul es o cc ur frequently on th e palms and/or so les of black patients but similar spots are unco mmon in white patients. We recently observed volar macules in 87 of 145 (60%) adult black patients seen in the affiliated outpatient c linics of Wayne State University. These maculcs vary in size from a few millimeters to two or more centimeters in diameter. They have a variabl e co nfiguration and outline, but are frequently ovoid with rather sharp regul ar borders (Fig. l) . In genSuppu rted by the Detru it Generai H ospital Research Curpurati on. Address fur reprint s: Thu ma s A. Chapel, M .D ., Department u f Derm atolugy and Syphilo lugy, Way ne State University, 540 E. Canfield Avenue, Detru it , MI 48 20 l. 00 11-9059179 / 0400/ 0222 / $00.70
eral , pigmented macular lesions on palms and soles may be junctional nevi, ephelides, postinflamm atory hyperpigmentation, or lentiginous malignant melanoma. Because we were unable to find any definitive histologic description of these multiple, asymptomatic macules in the literature, we elected to .remove severa! from the volar skin of patients at autopsy, the histology of which forms the basi s of this report.
Materials and Methods Punch specimens, 4 mm in diameter, were taken from pigmented macules on the volar surfaces of 15 cadavers at necropsy. The patients ranged in age from 24 to 83 years. Eleven were black, four white, seven women and eight men. Two of the 15 specimens were taken from the palm and the remainder from the so le. Ali of the spec imens were fixed in formali n, embedded in paraffin , and 1O mi c ron sections were stain ed with both hematoxyli n-eosin and acid orcein and Giemsa solution. In addition, one 4-mm punch biopsy of a typical pigmented palmar macule was taken from a 61-year-old black volunteer and stained with Dopa so lution for an accurate melanocyte count.
Results O ne of the 15 lesions examined hi stologica lly was an intradermal nevus ce li nevus. None of the rest co ntained any nevus ce ll s. Ali exhibited purely epid ermal hyperpigmentation and in some cases a few pi gmented macrophages in the derrni s. The generai configuratio n of the epidermi s was fairly normal and exhibited the usual fea-
© lnternation al 222
Soc iety o f Tropi ca l Derm ato logy, lnc.
No. 3
VOLAR MELANOTIC MACULES
tures of ridged volar skin with regularly spaced eccrine ducts (Fig. 2). The sweat duct ridges were unusually broad and possessed a squared-off horizontal lower border. No apparent increase in number of junctional melanocytes was evident on routine staining of specimens. The distribution of melanin granules exhibited three distinct types. The most common type showed a very dark pigmentation of the basai keratinocytes (basai type B) with barely any melanin visible in the subrabasal layers. Melanocytes were inconspicuous (Fig. 3). Hyperpigmentation was most pronounced on the lower part of the sweat duct ridges. Another group showed melanin granules in ali epidermallayers (epidermal type E) including basai cells, prickle cells, and corneocytes (Fig. 4). In the least common type, melanin granules were present in large and highly dendritic melanocytes (dendritic type D) while no or few pigmented granules were seen in keratinocytes (Fig. 5). Some of the specimens represented pure types B, D, or E, while in others, two or ali three types were mixed in one lesion. Melanin was present in the B, D, andE types of distribution in the Dopa-stained specimen but there was no appreciable increase in the number of junctional melanocytes.
Chape/, et al.
Fig. l .
223
Typical melanotic macules on the palm.
ti?n and need not be considered here in dtfferential diagnosis. Nevus spilus in the classica! sense design_ates congenita! pigmented spots of variable stze containing approximately norma! numb~rs of me_lanocytes and increased epidermal ptgmentatton of mild degree.t An acquired an~ progressive variant has recently been des~nbed as_cribriform and zosteriform hyperptgmentatton.2 The lesions in these and some
Discussion Circumscribed epidermal pigmentation is encountere d in human skin in freckles (ephelides), lentigines, and nevi spili (cafe au lait spots). Ephelides have somewhat fewer and larger active melanocytes than the surrounding skin, their keratinocytes contain more mela n in granules, and their clinica! and histologic appearance is influenced by sunlight. Lentigines are subdivided into the simplex (juvenile), senile, and malignant types. The juvenile and senile types show excess numbers of m~lanocytes in combination with accentuated rete ridges and peg-like basai buds. The keratinocytes contain melanin granules and, in lentigo simplex, may exhibit the highest degree of keratinocyte pigmentation seen anywhere in human skin . Lentigo maligna (Hutchinson 's melanotic freckle) has atypical melanocytic prolifera-
Fig. 2. Diagram of volar skin, reprodu ced with permi SSIOn and alt erations from F. Pinku s, Die Normale Anatomie der Haut, Fi g. 280. In : Jadassohn's H andbuch der H aut-und Geschlechtskrankheiten, vol. 1, part 1 Berlm , Spnnger-Verlag, 1927. Superfi cial rid ges and furrows and deep fol_ d s of the epidermi s have been give n a vanety o f des1gnat1on s m the literature. A = Dermatoglyphlc nd ge or cri sta ~ upe rfici a li s. B = Dermatoglyphi c ~rrow or sulcus supert1 c1al1 s. C = Ecc rine swea t pare. D ~ Sweat .duet nd ge, glandular fold , or cri sta profunda mtermed1 a. E = Limitin g dee p rid ge, furro w fold, or cri sta profund a l1m1tans.
224
INTERNATIONAL JOURNAL OF DERMATOLOGY
Aprii 1979
Vol. 18
Fi g. 3. Top, volar melanoti c macule, hi stologi c type B {Acid orce in and Giemsa x 60) . Fig. 4. Bott om , volar melanoti c mac ul e, mixed type, type E prevails as manifested by melanin in c lusions i n horny layer. A t right sid e of pi c tur e, type E merges into type B; at left sid e, dendritic ce lls of type D are present {Ac id orce in and Giemsa x 60) .
other reported cases are histologically similar, but clinically different because they are restricted to one or a few asymmetrical areas of body skin in contrast to the usually symmetrical volar pigmented macules.3 - 8 There exists, however, in another specialized part of the skin surface, one condition that seems to correspond rather closely to the macules under discussion. This condition is the pigmented macule on ~he vermillion of the lips which to our knowledge has been investigated only twice before under
the name solitary labiallentigo 9 and by labial melanotic macule, 10 the term we prefer. Both publications stress hyperpigmentation of the basai layer. The latter authors point out that the pigmentation is concentrated along the lower half of the rete ridges and that the suprapapillary epithelium is rarely pigmented. Neither publication 9 • 10 mentions the other two types of mel an in di stribution seen in the volar macules. Their photomicrographs show flat and square lower borders of rete ridges.
No. 3
VOLAR MELANOTIC MACULES
We there fore believ e that the labia l melan otic macules and the volar melan otic macules are closely related . lt remains to explain the mechanism of these hyperpigmentations. In as much as the numb er of melanocytes is not obvio usly increased, one has a postulate melan ocytic hyperfunction . However, ordina rily, when melan ocytic function is increased, either temporarily after irradiation, or genet ically in black skin, the "epidermal melan in unit" results in proportionate hyper pigme ntatio n of melanocytes and ali keratinocytes. lt is difficu lt to explain how in labial and the most comm on type of volar macules melan in granules are concentrated in the basallayers andar e not carri ed outwa rd with the maturing divisio n products into the spinous and keratinized layers . lt is even more intrigu ing to see in some lesions that this latter process is ìntact in sharply limite d colum nar foci while to the right and left, melanin is not carried upward. lt seems most likely that the latter phenomenon is due to some biolog ie dysfunction in the keratinocytes rather than in the melanocytes. The third (D) type seems to represent complete dissociation of the epidermal melan in unit. Almost no melanin granules are transferred into keratinocytes. This pigment block is ordina rily seen in acute or subacute inflamm atory condi tions and appears to be due to the ·i nabili ty of the diseased keratinocytes to accept melanin granules, which therefore accum ulate in the engorged dendr ites of melanocytes. 11 • 12 There is, however, no evidence of inflam matio n in the volar macules. One other and possibly homologous condi tion exists in the skin of the foot pads of black rats . This skin usual ly is mode rately pigmente d on gross inspe ction. Histo logic exam inatio n (Pink us , unpu blishe d communic ation) often shows large and deeply pigme nted dendri1ic melan ocyte s and no pigment in keratinocytes. lt seems possib le that volar skin, in rat and man, has less ability to phagocytize melanosomes than other skin
l. Pinku s, H., and Mehregan, A. : A Guide To Der-
225
D Fig. 5. Volar melanotic macule, histologi c type (Acid orcein and Giemsa x 200).
2.
3.
4. 5.
6. 7. 8.
9.
l O.
11 .
area s. References
Chape/, et al.
12.
matoh istopa tholog y, 2nd ed . N ew York, Appl eton-C entury-Crofts, 1976, p. 446. Rower, J.• Carr, R., and Lown ey, E.: Progressive . cribifo rm and zosteri form hype rpigm entatio n Arch. Dermatol. 114 :98, 1978. Selmanowitz, F., and Orentre ich, N.: Tardive pattern ed pigme nt ed ma eu le s. Are h. Derma tol. l 02 :483, 1970. ' Shumate, C. A.: Pigm ented unilate ral nevus- like lentigo. Are h. Dermatol. Syphilol. 43:41 O, 1941. Becker, S. W ., and Reuter, M . j. : A familial pigm en, tary anoma ly. Arch. Dermatol. Syphilo l. 40:987 1939. Cappon D: A case of unilaterall entigines with menta l deficiency. Br. J. Dermatol. 60:371 , 1948 . M cKe lway, J. L. : Lentigo: unilate ral distribu tion.NY St. J. Med. 80 : 197, 1940. Chernosky, M .E., Anderson, D. E., Chang, J. P. et al.: Familial progressive hyperpigm entation . Arch. Dermatol. l 03 :581 , 1971. Shapiro , L., and Zegare lli, D.: The solitary labial lentigo : a clinicop atholog i c study of twe nty cases. Ora l Surg. 31 :87, 1971 . , Weathers, D., Corio, R., Crawford, R., Giansanti , J. ra! O . macule tic melano labial and Page, L.: The Surg. 42:196 , 1976. Pinkus, H., Staricco, R. , Kropp, P., and Fan , J.: The symbiosis of melanocytes and human epid ermis under norma l and abnormal conditi ons. In : Pigment Celi Biology. Edited by Gordon , M. New York, Academic Press, 1959, p. 127. Pinku s, H., and M ehregan , A.: A Guide To Der, matoh i stopat hology , 2nd ed . N ew York Appleton-Century-Crofts, 1976, p. 47 .
