obsolete nevus

Obsolete Nevus: A Historical Term

The term "obsolete nevus" refers to a group of diseases that were previously classified under the Orphanet nomenclature of rare diseases but have since been obsoleted [1]. This term does not characterize a specific disease, but rather a collection of diseases that were once considered distinct entities.

Definition and Characteristics

Obsolete nevi are sharply circumscribed and chronic lesions of the skin or mucosa, commonly referred to as birthmarks or beauty marks [2]. They can appear in various forms, including pigmented spindle cell nevi, desmoplastic nevi, and epithelioid and spindle-cell nevi [3].

Types of Obsolete Nevus

Some specific types of obsolete nevus include:

• Spitz nevus: A pink or brown dome-shaped mole that arises in children and young adults [13].
• Pigmented spindle cell nevus: A very dark-colored mole with spindle-shaped dermal melanocytes, usually found on the limbs [5].
• Desmoplastic nevus: A type of nevi characterized by a thick, hystrix-like white or brownish hyperkeratosis [8].

Historical Context

The term "obsolete nevus" has been used in the past to describe these conditions, but it is no longer considered a valid medical term. The classification and diagnosis of these diseases have evolved over time, and they are now recognized as part of broader categories such as skin neoplasms [4].

References:

[1] Context 1 [2] Context 2 [3] Context 3 [4] Context 4 [5] Context 5 [8] Context 8 [13] Context 13

Based on the provided context, it appears that there are various types of nevi (moles) mentioned, but I'll focus on the signs and symptoms of an "obsolete" nevus, which is not explicitly mentioned in the search results. However, I can provide information on the general characteristics of nevi and some related conditions.

Common Characteristics of Nevi

• Most people have between 10 to 40 nevi (plural: nevi) [4]
• Common nevi are harmless collections of colored cells
• They typically appear as small, flat, or slightly raised spots

Related Conditions with Similar Signs and Symptoms

While there's no specific information on "obsolete" nevus, I can provide details on related conditions that might share similar signs and symptoms:

• Dysplastic Nevus: A type of atypical mole that differs from common moles in terms of size, shape, and color [3]. Signs and symptoms may include:
  • Larger size
  • Irregular shape
  • Color variation (e.g., darker or lighter than surrounding skin)
• Choroidal Nevus: A benign growth on the choroid layer of the eye. Symptoms are usually absent, but in rare cases, they might experience:
  • No symptoms at all [6]
  • Rarely, symptoms like proptosis (bulging eyes) and globe displacement
• Nevus Comedonicus Syndrome: A rare condition associated with various systemic abnormalities, including ocular, neurological, and skeletal anomalies. Signs and symptoms may include:
  • Various eye abnormalities
  • Skeletal deformities
  • Heart defects
  • Urogenital abnormalities

Please note that these conditions are not explicitly mentioned as "obsolete" nevi in the provided context. If you could provide more information or clarify what is meant by "obsolete nevus," I'd be happy to try and assist further.

References:

[3] Description of Dysplastic Nevus [4] Common Nevi Characteristics [6] Choroidal Nevus Symptoms

Based on the provided context, it appears that there are several diagnostic tests associated with dysplastic nevi (DN) or atypical nevi. Here are some relevant tests mentioned:

• Dermatoscopy: This is a non-invasive imaging technology used to examine skin lesions in detail [1].
• Tzanck testing: This test can be used to diagnose viral diseases, such as herpes simplex and herpes zoster, but it cannot distinguish between these two infections [3].
• Electron microscopy (EM): While not commonly required for routine diagnosis, EM can be useful for diagnosing rare genetic hair shaft disorders [13].

It's worth noting that the diagnostic tests mentioned in the context are not specific to obsolete nevi, but rather to various skin conditions. However, some of these tests may still be relevant when considering the diagnosis and management of dysplastic nevi.

In terms of more modern or advanced diagnostic tests, there is a mention of genetic testing, particularly gene expression panels, which has been explored by researchers as an aid in diagnosing cases without a biopsy [11].

It's also mentioned that in many cases, ancillary studies or simply more clinical information may permit a definitive diagnosis, but it is not uncommon that even after comprehensive evaluation, a definitive diagnosis may still be challenging [14].

Based on the provided context, it appears that there are various treatment options available for nevus, including drug treatments.

• Topical imiquimod has been explored as a potential treatment to decrease recurrence after ablative laser (Er:YAG) treatment [3].
• Vismodegib, a pill taken orally, has been shown to prevent and shrink tumors in people with basal cell nevus syndrome [8][9]. However, it's essential to note that this information is related to basal cell nevus syndrome rather than the general term "obsolete nevus".
• Lenvatinib and pembrolizumab combination therapy was effective in treating congenital melanocytic nevi (CMN) that were resistant to trametinib [5].

It's worth noting that the context mentions various types of treatments, including laser therapy, cryosurgery, radiation therapy, and topical agents like salicylic acid and retinoic acid. However, it does not specifically mention drug treatment for "obsolete nevus".

If we consider "obsolete nevus" as a term referring to any type of nevus that is no longer considered relevant or significant (e.g., junctional nevi), the available information on topical imiquimod and vismodegib might be applicable. However, it's crucial to consult a medical professional for personalized advice.

References: [3] Zhao Y. Topical imiquimod in decreasing recurrence after ablative laser treatment. [2024] [5] Jiang R. Combination of lenvatinib and pembrolizumab in treating congenital melanocytic nevi. [2024] [8] Vismodegib prevents and shrinks tumors in basal cell nevus syndrome. [2012] [9] Becker LR. Novel dosing regimen of vismodegib for decreased toxicity. [2017]

Please note that the information provided is based on the context, which might not be directly related to "obsolete nevus". A medical professional should be consulted for accurate and personalized advice.

The differential diagnosis of an obsolete nevus refers to the process of ruling out other possible conditions that may present similarly to a nevus, but are no longer considered valid or relevant in modern medical practice.

According to search result [13], the differential diagnosis of nevus sebaceus (a type of congenital melanocytic nevus) depends on the stage of development. In early infancy, the differential diagnosis may include aplasia cutis congenita or mastocytoma. Other differential diagnoses in later stages of development include congenital nevus, epidermal nevus, seborrheic keratosis, verruca, and juvenile xanthogranuloma.

It's worth noting that the term "obsolete" is not a medical condition per se, but rather a description of something that is no longer considered relevant or valid. Therefore, it's unclear what specific type of nevus you are referring to. However, based on the provided context, it appears that the differential diagnosis for various types of nevi may include other conditions such as aplasia cutis congenita, mastocytoma, and seborrheic keratosis.

Here are some possible conditions that may be considered in the differential diagnosis of an obsolete nevus:

• Aplasia cutis congenita: a rare congenital disorder characterized by the absence or underdevelopment of skin
• Mastocytoma: a type of mast cell tumor that can occur on the skin
• Seborrheic keratosis: a benign growth that can appear on the skin, often in older adults
• Verruca: a type of wart caused by the human papillomavirus (HPV)
• Juvenile xanthogranuloma: a rare condition characterized by the presence of yellowish nodules or patches on the skin

It's essential to consult with a medical professional for an accurate diagnosis and treatment plan.