Intradermal Nevus Fibrosis

1. Clark WH Jr, Elder DE, Guerry D IV, et al. A study of tumor progression: the precursor lesions of superficial spreading and nodular melanoma. Human Pathol 1984; 15:1147-1165.

2. Elder DE. The dysplastic nevus. Pathology 1985; 17:291-297.

3. Barnhill RL, Roush GC, Duray PH. Correlation of histologic and cytoplasmic features with nuclear atypia in atypical (dysplastic) nevomelanocytic nevi. Hum Pathol 1990; 21:51-58.

4. Piepkorn MW. An appraisal of the dysplastic nevus syndrome concept. Adv Dermatol 1991; 6:35-55; discussion 56.

5. Weinstock MA, Barnhill RL, Rhodes AR, Brodsky GL. Reliability of the histopathologic diagnosis of melanocytic dysplasia. The Dysplastic Nevus Panel. Arch Dermatol 1997; 133:953-958.

6. Piepkorn M. Whither the atypical (dysplastic) nevus? Am J Clin Pathol 2001; 115:177-179.

7. Shors AR, Kim S, White E, et al. Dysplastic naevi with moderate to severe histological dysplasia: a risk factor for melanoma. Br J Dermatol 2006; 155(5):988-993.

aEssential features needed for diagnosis. Either lentiginous melanocytic proliferation or variation in junctional nesting is acceptable.

Well Defined Dermal Cyst
Figure 1 (A) Lentigo simplex. Note well-circumscribed borders and uniform dark brown color. (B) The lesion demonstrates elongated epidermal rete, basal layer hyperpigmentation, and slightly increased numbers of single basilar melanocytes concentrated on the epidermal rete.
Moderate Dysplastic Mole Lentigo Simplex Pathology

Figure 2 (A) Compound nevus. The lesion is symmetrical, well defined, and has uniform brown color. (B) Dermal nevus. The lesion is small, symmetrical, well defined, and has regular borders. (C) Compound nevus. Note symmetry and regular distribution of melanocytes in junctional and dermal nests. (D) Higher magnification showing uniform cytological features of melanocytes.

Figure 2 (A) Compound nevus. The lesion is symmetrical, well defined, and has uniform brown color. (B) Dermal nevus. The lesion is small, symmetrical, well defined, and has regular borders. (C) Compound nevus. Note symmetry and regular distribution of melanocytes in junctional and dermal nests. (D) Higher magnification showing uniform cytological features of melanocytes.

Dermal FibrosisLentigo Simplex Pathology

Figure 3 (A) Dermal nevus. There Is maturation from epithelioid-type cells at the top of the nevus to lymphocytoid cells and finally to cells with schwannian differentiation at the base. (B) Epithelioid (or "type A") nevus cells. The melanocytes are present in rounded nests in the superficial dermis. The cells demonstrate abundant eosinophilic cytoplasms, often with syncytial appearances. The nuclei are round or oval and display fairly uniform chromatin. (C) Lymphocytoid (or "type B") nevus cells. These nevus cells have little or no demonstrable cytoplasm and contain uniform nuclei that are often slightly smaller than those present in type A cells. (D) Spindle (or "type C") nevus cells. These melanocytes commonly have not only spindle-shaped morphologies but also often display neural or schwannian differentiation ("neurotization") in patterns often indistinguishable from a peripheral nerve sheath tumor. These nevus cells are usually sparsely scattered in a delicate fibrous matrix and may form the rather characteristic "neural tubules."

Perifer Edema Facial Nevus Lentiginous Hyperplasia

Figure 4 (A) Halo melanocytic nevus. Note symmetry and well-delineated nature of the halo and central nevus. (B) Halo melanocytic nevus. A compound nevus is obscured by a dense lymphocytic infiltrate. The nevus shows maturation and lacks significant atypia. (C) Acral melanocytic nevus. The nevus shows small diameter, symmetry, regular borders, and fairly uniform tan-brown color. (D) Acral melanocytic nevus. A compound nevus demonstrating lentiginous melanocytic hyperplasia and noticeable pagetoid melanocytosis—both features raising concern for acral melanoma. However, the lesion has regular nesting of melanocytes and does not show the pronounced cytological atypia of melanoma.

Atypical Lentiginous Hyperplasia

Figure 5 (A) Recurrent/persistent melanocytic nevus. The lesion demonstrates somewhat irregular macular pigmentation within the clinical scar of previous biopsy of a nevus. (B) Irregular nesting of melanocytes along dermal-epidermal junction and overlying dermal cicatrix from previous biopsy. Residual dermal nevus from the original lesion is present deep to the cicatrix (not observed in this photo). (C) Higher maginification of (B) shows irregular junctional nesting of melanocytes without significant atypia.

Figure 5 (A) Recurrent/persistent melanocytic nevus. The lesion demonstrates somewhat irregular macular pigmentation within the clinical scar of previous biopsy of a nevus. (B) Irregular nesting of melanocytes along dermal-epidermal junction and overlying dermal cicatrix from previous biopsy. Residual dermal nevus from the original lesion is present deep to the cicatrix (not observed in this photo). (C) Higher maginification of (B) shows irregular junctional nesting of melanocytes without significant atypia.

Vulvar Nevus Vulvar Pigmentation

Figure 6 (A) Genital melanocytic nevus. The lesion is symmetrical, well defined, has uniform brown color, measures about 1 cm in diameter, and possesses a minimally elevated topography. (B) Genital (vulvar) melanocytic nevus. Note symmetrical polypoid profile. (C) Genital (vulvar) melanocytic nevus. This compound nevus has an extensive (bulky) dermal component of regularly dispersed nests of nevus cells and shows maturation. (D) Genital (vulvar) melanocytic nevus. This lesion exhibits hypercellular, discohesive, and somewhat irregular junctional nesting. The junctional melanocytes are enlarged and contain slightly to moderately atypical nuclei.

Figure 6 (A) Genital melanocytic nevus. The lesion is symmetrical, well defined, has uniform brown color, measures about 1 cm in diameter, and possesses a minimally elevated topography. (B) Genital (vulvar) melanocytic nevus. Note symmetrical polypoid profile. (C) Genital (vulvar) melanocytic nevus. This compound nevus has an extensive (bulky) dermal component of regularly dispersed nests of nevus cells and shows maturation. (D) Genital (vulvar) melanocytic nevus. This lesion exhibits hypercellular, discohesive, and somewhat irregular junctional nesting. The junctional melanocytes are enlarged and contain slightly to moderately atypical nuclei.

Giant Congenital Melanocytic Nevus Giant Congenital Melanocytic Nevus

Figure 7 (A) Intermediate-sized congenital melanocytic nevus. The lesion is well defined with somewhat speckled brown color. (B) Small congenital melanocytic nevus. Note pattern of discreet nesting of melanocytes in reticular dermis that resembles a lymphocytic infiltrate. (C) Giant congenital melanocytic nevus. There is diffuse infiltration of the reticular dermis by nevus cells. (D) Giant congenital melanocytic nevus. Higher magnification of (C) showing orderly pattern of small uniform nevus cells in dermis.

Figure 7 (A) Intermediate-sized congenital melanocytic nevus. The lesion is well defined with somewhat speckled brown color. (B) Small congenital melanocytic nevus. Note pattern of discreet nesting of melanocytes in reticular dermis that resembles a lymphocytic infiltrate. (C) Giant congenital melanocytic nevus. There is diffuse infiltration of the reticular dermis by nevus cells. (D) Giant congenital melanocytic nevus. Higher magnification of (C) showing orderly pattern of small uniform nevus cells in dermis.

Giant Congenital Melanocytic Nevus

Figure 8 (A) Atypical dermal nodular melanocytic proliferation arising In giant congenital melanocytic nevus. The nodular proliferation Is present in the mid-dermis and is fairly well circumscribed. (B) There is some transition to the surrounding congenital nevus. (C) The nodule shows cytological atypia of melanocytes and rare mitoses. The tumor lacks sufficient atypicality for melanoma.

Figure 8 (A) Atypical dermal nodular melanocytic proliferation arising In giant congenital melanocytic nevus. The nodular proliferation Is present in the mid-dermis and is fairly well circumscribed. (B) There is some transition to the surrounding congenital nevus. (C) The nodule shows cytological atypia of melanocytes and rare mitoses. The tumor lacks sufficient atypicality for melanoma.

Intradermal Nevus Histology
(B)
Intradermal Nevus Histology

Figure 9 (A) Spitz tumor. The lesion is a symmetrical, reddish-pink dome-shaped nodule with uniform smooth surface. (B) Compound Spitz tumor. Corresponding symmetrical and well-circumscribed configuration of lesion at scanning magnification. (C) Compound Spitz tumor. Characteristic enlarged spindle cells and epithelioid cells arranged in vertically-oriented ("raining down") fascicles and nests, respectively, at the dermal-epidermal junction. (D) The melanocytes have eosinophilic "ground glass" cytoplasms and large nuclei with dispersed delicate chromatin.

Figure 9 (A) Spitz tumor. The lesion is a symmetrical, reddish-pink dome-shaped nodule with uniform smooth surface. (B) Compound Spitz tumor. Corresponding symmetrical and well-circumscribed configuration of lesion at scanning magnification. (C) Compound Spitz tumor. Characteristic enlarged spindle cells and epithelioid cells arranged in vertically-oriented ("raining down") fascicles and nests, respectively, at the dermal-epidermal junction. (D) The melanocytes have eosinophilic "ground glass" cytoplasms and large nuclei with dispersed delicate chromatin.

Intradermal Nevus

Figure 10 (A) Compound Spitz tumor with atypical features. The lesion demonstrates the following abnormal features: "nodule formation" (hypercellularity and confluence of melanocytes), the lack of maturation, and significant depth. (B) Higher magnification shows effacement of epidermis and the nodular appearance of the dermal component. (C) This lesion demonstrates a nodular growth pattern and dense cellularity at its base, attributes suggesting some risk for an aggressive tumor. (D) Markedly atypical compound Spitz tumor. This lesion demonstrates a diffuse infiltration of the dermis without any maturation and pronounced pleomorphism of melanocytes.

Dermal Fibrosis
(B)
Intradermal Nevi

Figure 11 (A) Pigmented spindle cell melanocytic tumor. The lesion is small with regular well-defined borders and uniform brown-black color. The tumor also demonstrates a slightly elevated plaque-type topography. (B) Pigmented spindle cell melanocytic tumor. Histologically the tumor is a uniform well-circumscribed plaque comprised of hyperplastic epidermis and the junctional aggregates of pigmented spindled melanocytes. (C) Intraepidermal nests and vertically-oriented fascicles of spindle cells are regularly and unobstrusively arrayed within the fabric of the epidermis. (D) The spindle cells are uniform with delicate basophilic chromatin.

Intradermal Nevus

Figure 12 (A) Common blue nevus. Note small diameter, striking symmetry, regular and sharply-defined borders, and blue-black coloration. (B) Common blue nevus. The lesion exhibits a dermal fibrotic nodule containing dendritic melanocytes and melanophages. (C) Higher magnification showing dendritic melanocytes with small uniform nuclei.

Figure 12 (A) Common blue nevus. Note small diameter, striking symmetry, regular and sharply-defined borders, and blue-black coloration. (B) Common blue nevus. The lesion exhibits a dermal fibrotic nodule containing dendritic melanocytes and melanophages. (C) Higher magnification showing dendritic melanocytes with small uniform nuclei.

Figure 13 (A) Cellular blue nevus. There is a "biphasic" pattern as evidenced by a "common blue nevus" zone superficially giving place to a deeper lobular "cellular" component, which extends into subcutaneous fat. (B) The pale-staining lobular component is composed of bundles of generally amelanotic spindle cells. (C) Higher magnification showing spindled melanocytes in amelanotic cellular component. (D) The spindle cells have eosinophilic to vacuolated cytoplasms and relatively uniform nuclei.

Figure 13 (A) Cellular blue nevus. There is a "biphasic" pattern as evidenced by a "common blue nevus" zone superficially giving place to a deeper lobular "cellular" component, which extends into subcutaneous fat. (B) The pale-staining lobular component is composed of bundles of generally amelanotic spindle cells. (C) Higher magnification showing spindled melanocytes in amelanotic cellular component. (D) The spindle cells have eosinophilic to vacuolated cytoplasms and relatively uniform nuclei.

Figure 14 (A) Melanocytic nevus with phenotypic heterogeneity (combined nevus). The lesion has bluish color suggesting a blue nevus. (B) A conventional dermal nevus is present superficially and gives place to a plexiform pigmented spindle cell component present in the superficial and deep dermis. (C) Higher magnification shows transition from dermal nevus to pigmented spindle cell component. (D) The latter component is comprised pigmented spindle cells in confluent bundles. The melanocytes display some nuclear enlargement and pleomorphism.

Figure 14 (A) Melanocytic nevus with phenotypic heterogeneity (combined nevus). The lesion has bluish color suggesting a blue nevus. (B) A conventional dermal nevus is present superficially and gives place to a plexiform pigmented spindle cell component present in the superficial and deep dermis. (C) Higher magnification shows transition from dermal nevus to pigmented spindle cell component. (D) The latter component is comprised pigmented spindle cells in confluent bundles. The melanocytes display some nuclear enlargement and pleomorphism.

Dermal Melanocytic Disorders

Figure 15 (A) Atypical melanocytic nevus. Note asymmetry, slightly irregular borders, and complex coloration with admixture of tan, brown, pink, red, and dark brown. (B) Compound nevus with architectural disorder and cytological atypia. The nevus displays irregular patterns of nesting, lentiginous (basilar single-cell) melanocytic proliferation, and variable cytological atypia of intraepidermal melanocytes. (C) Compound nevus with architectural disorder and cytological atypia. The intraepidermal melanocytes show confluence along the basal layer. (D) The melanocytes striking exhibit nuclear enlargement, nuclear pleomorphism, and some hyperchromatism.

Figure 15 (A) Atypical melanocytic nevus. Note asymmetry, slightly irregular borders, and complex coloration with admixture of tan, brown, pink, red, and dark brown. (B) Compound nevus with architectural disorder and cytological atypia. The nevus displays irregular patterns of nesting, lentiginous (basilar single-cell) melanocytic proliferation, and variable cytological atypia of intraepidermal melanocytes. (C) Compound nevus with architectural disorder and cytological atypia. The intraepidermal melanocytes show confluence along the basal layer. (D) The melanocytes striking exhibit nuclear enlargement, nuclear pleomorphism, and some hyperchromatism.

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Responses

  • PEONY
    Which kind of diseases is pleomorphic melanocytic neoplasm?
    4 years ago

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