Nevus

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Not to be confused with Naevius, Nevis, or Nevius.
Nevus
1D-I-k ouC8.jpg
A mole on a leg
Classification and external resources
Specialty dermatology
ICD-10 I78.1
ICD-9-CM 448.1, 216.0-216.9
MeSH D009506

Nevus (plural: nevi) is a nonspecific medical term for a visible, circumscribed, chronic lesion of the skin or mucosa.[1] The term originates from nævus, which is Latin for "birthmark," however, a nevus can be either congenital (present at birth) or acquired. Common terms, including mole, birthmark, and beauty mark, are used to describe nevi, but these terms do not distinguish specific types of nevi.

Classification[edit]

The term nevus is applied to a number of pigmentation disorders, both hypomelanotic and hypermelanotic,[2] as well as neoplasias and hyperplasias of melanocytes.[3]

Hypomelanotic[edit]

Hypermelanotic[edit]

Additional types of nevi do not involve disorders of pigmentation or melanocytes. These additional nevi represent hamartomatous proliferations of the epithelium,[7] connective tissue,[8] and vascular malformations.[9]

Epidermal nevi[edit]

Connective tissue nevi[edit]

Vascular nevi[edit]

Diagnosis[edit]

Nevi are typically diagnosed clinically with the naked eye or using dermatoscopy. More advanced imaging tests are available for distinguishing melanocytic nevi from melanoma, including computerized dermoscopy and image analysis.[10] The management of nevi depends on the type of nevus and the degree of diagnostic uncertainty. Some nevi are known to be benign, and may simply be monitored over time. Others may warrant more thorough examination and biopsy for histopathological examination. For example, a clinician may want to determine whether a pigmented nevus is a type of melanocytic nevus, dysplastic nevus, or melanoma as some of these skin lesions pose a risk for malignancy. In addition to histopathological examination, some lesions may also warrant ancillary tests to aid in diagnosis, including special stains, immunohistochemistry, and electron microscopy.[11]

Differential diagnoses[edit]

Hypermelanotic nevi must be differentiated from other types of pigmented skin lesions, including:[5][6]

Treatment[edit]

Cryotherapy

The treatment of a nevus depends on the specific diagnosis, however, the options for treatment generally include the following modalities:

Syndromes[edit]

Etymology[edit]

A nevus may also be spelled naevus. The plural is nevi or naevi. The word is from nævus, Latin for "birthmark".

References[edit]

  1. ^ Happle, Rudolf (1995). "What is a nevus? A proposed definition of a common medical term.". Dermatology. 191(1): 1–5. 
  2. ^ "Chapter 75. Hypomelanoses and Hypermelanoses". Fitzpatrick's Dermatology in General Medicine. The McGraw Hill Companies, Inc. 2012. ISBN 978-0-07-166904-7. 
  3. ^ a b c d e "Chapter 122. Benign Neoplasias and Hyperplasias of Melanocytes". Fitzpatrick's Dermatology in General Medicine. The McGraw-Hill Companies, Inc. 2012. ISBN 978-0-07-166904-7. 
  4. ^ "Dysplastic (Atypical) Nevi". Melanocytic Lesions - Springer. doi:10.1007/978-1-4939-0891-2. 
  5. ^ a b "Dermal melanocytosis". Melanocytic Lesions - Springer. doi:10.1007/978-1-4939-0891-2. 
  6. ^ a b "Lentigo, Other Melanosis, and the Acquired Nevus". Melanocytic Lesions - Springer. doi:10.1007/978-1-4939-0891-2. 
  7. ^ "Chapter 118. Benign Epithelial Tumors, Hamartomas, and Hyperplasias.". Fitzpatrick's Dermatology in General Medicine. The McGraw-Hill Companies, Inc. 2012. ISBN 978-0-07-166904-7. 
  8. ^ "Chapter 66. Dermal Hypertrophies and Benign Fibroblastic/Myofibroblastic Tumors.". Fitzpatrick's Dermatology in General Medicine. The McGraw-Hill Companies, Inc. 2012. ISBN 978-0-07-166904-7. 
  9. ^ "Chapter 172. Vascular Malformations.". Fitzpatrick's Dermatology in General Medicine. The McGraw Hill Companies, Inc. 2012. ISBN 978-0-07-166904-7. 
  10. ^ Rigel, Darrell S.; Russak, Julie; Friedman, Robert (2016-10-01). "The evolution of melanoma diagnosis: 25 years beyond the ABCDs". CA: a cancer journal for clinicians. 60 (5): 301–316. doi:10.3322/caac.20074. ISSN 1542-4863. PMID 20671054. 
  11. ^ "Ancillary Techniques in Diagnosing Melanocytic Lesions". Melanocytic Lesions - Springer. doi:10.1007/978-1-4939-0891-2. 

External links[edit]