Skin melanocytic tumor
Blue nevi, pigmented epithelioid melanocytomas and dermal melanocytoses
Cellular blue nevus
Author: Christopher S. Hale, M.D.
Topic Completed: 1 August 2014
Minor changes: 15 January 2021
Copyright: 2003-2021, PathologyOutlines.com, Inc.
PubMed Search: cellular blue nevus
Table of Contents
Definition / general | Epidemiology | Sites | Clinical features | Case reports | Treatment | Clinical images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Molecular / cytogenetics description | Videos | Differential diagnosisCite this page: Hale CS. Cellular blue nevus. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/skintumormelanocyticbluenevuscellular.html. Accessed January 17th, 2021.
Definition / general
- Usually pigmented, biphasic tumor with component of classic blue nevus and distinct cellular areas composed of spindled to oval melanocytes with clear or finely-pigmented cytoplasm (Arch Pathol Lab Med 2011;135:327)
Epidemiology
- Benign, but rarely recurs or involves regional lymph nodes (J Cutan Pathol 2010;37:102)
- Melanomas may arise from cellular blue nevus (controversial, J Cutan Pathol 2012;39:1094)
Sites
- Buttock and sacrococcygeal areas are most common
- Also scalp, face, dorsal hands and feet
Clinical features
- Amelanotic tumors have atypical clinical appearance
- Large (> 1.5 cm) with intense pigmentation
Case reports
- 14 year old boy with a giant, infiltrative, facial tumor (J Clin Pathol 2007;60:82)
- 19 year old man with 0.5 cm epidermal cyst (Case of the Week #7)
- 19 year old man with pilonidal sinus (J Cutan Pathol 2007;34:942)
- 28 year old woman with intracranial extension (J Clin Neurosci 2000;7:453)
- 31 year old man with xanthomatosis and diabetes mellitus (Indian J Dermatol Venereol Leprol 2001;67:200)
- 34 year old man with nevus cells in sentinel lymph node (Eur J Dermatol 2008;18:586)
- Eyelid tumors (J Am Acad Dermatol 2008;58:257)
Treatment
- Excision
Clinical images
Contributed by Mark R. Wick, M.D.
Cellular blue nevus (breast skin)
Images hosted on other servers:
Infiltrative giant cellular blue nevus
Microscopic (histologic) description
- Well-circumscribed collection of interweaving fascicles with increased cellularity and extension into subcutis
- Heavily pigmented spindle cells alternate with clear cells
- Have pushing margins and variable fasciculation and neural structures
- No / minimal atypia; no junctional activity, no epidermal invasion, no peripheral inflammation, no necrosis and no / rare mitotic figures
- Scalp lesions may have intracranial extension
- “Ancient” blue nevi show stromal changes of large dilated vessels with pseudoangiomatous features, hyaline angiopathy, myxoid changes, sclerosis or hyalinization of stroma and variable edema, similar to ancient melanocytic nevi (Am J Dermatopathol 2008;30:1)
- Variants include amelanotic (Am J Surg Pathol 2002;26:1493) or with balloon cell change
- Note: benign cellular blue nevi may involve lymph node parenchyma and sinuses in a metastatic-like pattern; as a result, some tumors are best classified as having “uncertain biologic behavior”
Microscopic (histologic) images
Contributed by Mark R. Wick, M.D.
Cellular type, breast
Case #7
Low / medium power
High power
Contributed by Angel Fernandez-Flores, M.D., Ph.D.
Various images
Images hosted on other servers:
Infiltrative giant cellular blue nevus
Negative stains
- No / low Ki-67
Molecular / cytogenetics description
- No chromosomal aberrations (Am J Surg Pathol 2005;29:1214)
Videos
Differential diagnosis
- Cellular neurothekeoma
- Dermatofibroma
- Malignant blue nevus: scalp or heel lesion with marked nuclear atypia, numerous mitotic figures, some atypical and necrosis; variable epithelioid tumor cells
- Myoepithelioma
