reactive cutaneous fibrous lesion

A reactive cutaneous fibrous lesion, also known as dermatofibroma or fibrous histiocytoma, is a common benign skin lesion characterized by overexpression of collagen during wound healing.

Characteristics:

• Variable color: skin-colored to brown to purple
• Variable shape: plaques, nodules, or polyps
• Covered by intact skin
• Suspected by pinching the nodule between the fingers and observing that the tumor is fixed within the dermis (pinch sign)
• Overlying skin dimples on pinching the lesion

Definition:

A reactive cutaneous fibrous lesion is a benign, epidermal skin lesion characterized by overexpression of collagen during wound healing. It can occur anywhere on the skin and varies in size from 0.5-1.5 cm diameter.

Synonyms:

Reactive cutaneous fibrous lesion is also known as dermatofibroma or fibrous histiocytoma.

Clinical Presentation:

Dermatofibromas are commonly found on the extremities, particularly on the legs, and are more common in females. They are usually asymptomatic and can be diagnosed clinically with a patient history of a solitary, slow-growing cutaneous nodule.

Histology:

The histological appearance of dermatofibroma is characterized by the proliferation of benign spindle cells within the dermis. Various histologic subtypes exist, and treatment is usually not necessary.

References:

• [1] A benign, epidermal skin lesion characterized by overexpression of collagen during wound healing. (Source: NCI)
• [2-3] Variable color, shape, and clinical presentation of dermatofibroma. (Sources: An Bras Dermatol 2014;89:472 and various other sources)
• [4-5] Definition and synonyms for reactive cutaneous fibrous lesion. (Sources: MONDO:0006603 and EXPERIMENTAL FACTOR ONTOLOGY - ANNOTATIONS)
• [6-8] Histological appearance and clinical presentation of dermatofibroma. (Sources: EXPERIMENTAL FACTOR ONTOLOGY - ANNOTATIONS, JL Hornick 2020, and various other sources)

Reactive cutaneous fibrous lesions, also known as dermatofibromas or benign fibrous histiocytomas, can be diagnosed through a combination of clinical evaluation and diagnostic tests.

Clinical Evaluation The diagnosis of reactive cutaneous fibrous lesions is often made clinically, based on the patient's history and physical examination. The typical presentation includes a firm, tan-brown nodule on the skin, most commonly found on the legs. The lesion is usually asymptomatic and may be accompanied by a dimple or pinch sign when pressed.

Diagnostic Tests While clinical evaluation is often sufficient for diagnosis, diagnostic tests can be used to confirm the presence of reactive cutaneous fibrous lesions and rule out other conditions. Some common diagnostic tests include:

• Histological examination: A skin biopsy can be performed to examine the histological features of the lesion. The biopsy sample is typically taken from the edge of the lesion.
• Immunohistochemistry: This test can help identify specific markers, such as CD163, that are present in reactive cutaneous fibrous lesions.
• Dermatoscopy: Dermatoscopy, also known as epiluminescence microscopy, can be used to examine the skin lesion in detail and identify characteristic features

Based on the provided context, it appears that dermatofibromas are benign skin lesions that do not typically require treatment. However, if a dermatofibroma is causing concern or discomfort, surgical removal may be considered.

Regarding drug treatment for reactive cutaneous fibrous lesions, such as dermatofibromas, there is limited information available in the provided context. However, it mentions that previous scar treatment included an intralesional injection containing triamcinolone at a dose of 10 mg/mL at monthly intervals (Context #4).

Additionally, Context #13 mentions MRI and CT scans

The differential diagnosis of reactive cutaneous fibrous lesions involves considering various conditions that can present similarly to dermatofibromas or fibrous histiocytomas. Based on the search results, here are some key points to consider:

• Dermatofibrosarcoma protuberans (DFSP): This is a rare skin cancer that can mimic the appearance of a dermatofibroma. It's essential to rule out DFSP in cases where the lesion is large or has a characteristic "honeycomb" appearance [1].
• Atypical mole: Also known as a dysplastic nevus, this type of mole can be confused with a dermatofibroma due to its similar appearance and location on the skin. However, atypical moles tend to have irregular borders and color variations [2].
• Basal cell carcinoma: This is the most common form of skin cancer, and it can sometimes resemble a dermatofibroma in terms of its size and shape. However, basal cell carcinomas typically have a characteristic "pearly" appearance and may bleed or ooze fluid when pressed [