obsolete skin appendage carcinoma

Obsolescence in Skin Appendage Carcinoma

Skin appendage carcinomas, also known as adnexal carcinomas, are rare and heterogeneous neoplasms that arise from the skin's appendages, including sebaceous glands, sweat glands, and hair follicles. While these tumors were once considered distinct entities, advances in pathology have led to a reevaluation of their classification.

Historical Context

The classic monograph "Appendage Tumors of the Skin" was published in 1968, providing a comprehensive overview of these neoplasms. However, subsequent studies have revealed that many of these tumors are actually variants of more common skin cancers, such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC).

Current Understanding

The majority of skin appendage carcinomas can be classified into three main categories:

• Sebaceous Carcinoma: A rare and aggressive tumor arising from the sebaceous glands.
• Apocrine Carcinoma: A malignant adnexal carcinoma showing clear evidence of apocrine differentiation, typically affecting middle-aged or elderly females.
• Eccrine Carcinoma: A rare and poorly understood neoplasm arising from the eccrine sweat glands.

Obsolescence

The term "skin appendage carcinoma" is becoming increasingly obsolete as our understanding of these tumors evolves. Many of these neoplasms are now recognized as variants of more common skin cancers, rather than distinct entities. The classification of these tumors continues to be refined, and the use of specific terminology may eventually become unnecessary.

References

• [3] A carcinoma arising from the sebaceous glands, sweat glands, or the hair follicles. Representative examples include sebaceous carcinoma, apocrine carcinoma, ...
• [13] Skin appendage carcinoma (64000002); Adnexal carcinoma (64000002) Monarch Initiative: MONDO:0006973: Definition.
• [14] Cutaneous appendage (adnexal) tumors encompass both benign and malignant neoplasms and have been traditionally classified by their line of differentiation toward normal adnexal structures of the skin.

Based on the provided context, it appears that there are various diagnostic tests available for skin appendage carcinomas, including:

• Imaging techniques: Dermatoscopy is a non-invasive imaging technique used to examine pigmented skin lesions under high magnification [4]. However, its effectiveness in diagnosing skin appendage carcinomas specifically is unclear.
• Histopathological examination: This is the primary diagnostic method for skin appendage carcinomas. Histologic sections can render a diagnosis in most instances, but immunohistochemistry may be used as an ancillary tool to narrow down the differential diagnosis [15].
• Clinical evaluation: A thorough clinical evaluation, including a complete description of cutaneous findings, is crucial for accurate dermatologic diagnosis [12].

It's worth noting that the diagnostic accuracy of these tests can vary depending on the specific type of skin appendage carcinoma and the expertise of the healthcare provider.

Regarding obsolete skin appendage carcinomas, it appears that there are some outdated classification systems and nomenclature used in the past. For example:

• Appendageal tumors: This term encompasses both benign and malignant neoplasms that exhibit morphological differentiation toward one or more adnexal structures in normal skin [11].
• Cutaneous appendage (adnexal) tumors: These are traditionally classified by their line of differentiation toward normal adnexal structures of the skin, including eccrine, apocrine, follicular, and sebaceous types [13].

However, it's essential to note that these classification systems may not be widely used or accepted in modern dermatopathology.

References:

[11] Context result 11 [12] Context result 12 [13] Context result 13 [15] Context result 15

Based on the provided context, it appears that there are various treatment options for skin appendage carcinomas, which include:

• Taxane-based regimens: These are used as single-agent treatments for certain types of skin appendage carcinomas (EMPDs) [1][6].
• Cisplatin and fluoropyrimidine-based regimens: These are also used as single-agent treatments for EMPDs [1][6].
• Topical calcineurin inhibitors: These can be prescribed when local inflammation is severe [5].
• Surgical resection and skin histopathological biopsy: These can be used to diagnose and treat certain types of skin appendage carcinomas [5].

It's worth noting that the effectiveness of these treatments may vary depending on the specific type and severity of the carcinoma.

Additionally, there are some preventative measures that can be taken to prevent rash development in patients undergoing treatment for skin appendage carcinomas. These include:

• Preventative agents: Such as gentle cleansers and moisturisers [2].
• Oral doxycycline or minocycline: Can be used to prevent rash development [2].

It's also worth mentioning that there are some newer treatments being explored for skin appendage carcinomas, such as:

• Enfortumab vedotin: This has been shown to have a survival benefit compared to chemotherapy in certain patients with skin appendage carcinomas [4].
• Cetuximab plus radiotherapy: This represents an active and tolerable treatment option for certain types of skin appendage carcinomas, including those with contraindications for checkpoint inhibitor therapy [10].

References:

[1] by M Ishii · 2020 · Cited by 12 [2] by R Ladwa · 2024 [5] by G Zhu · 2024 · Cited by 1 [6] by M Ishii · 2020 · Cited by 11 [4] by ME Lacouture · 2022 · Cited by 78 [10] by M Chang · 2023 · Cited by 7

The differential diagnosis of obsolete skin appendage carcinoma involves considering various other types of tumors that may present similarly to this condition.

According to the search results, the differential diagnoses for skin appendage carcinomas include:

• Basal cell carcinoma (BCC) [15]
• Sebaceous trichofolliculoma
• Folliculosebaceous cystic hamartoma
• Adnexal and skin appendage neoplasms, which are a heterogeneous group of benign and malignant tumors that may differentiate towards one of the four primary skin adnexal elements (hair follicles, sebaceous glands, apocrine glands, and eccrine glands) [15]

It's also worth noting that the clinical presentation of skin appendage tumors is often not specific and diverse, making differential diagnosis challenging. However, immunohistochemistry can be a useful ancillary tool in diagnostic dermatopathology to narrow down the differential diagnoses for neoplasms of cutaneous appendages [12].

In terms of obsolete skin append