obsolete cutaneous fibrohistiocytic neoplasm

Fibrosarcoma of Bone vs. Cutaneous Fibrous Histiocytoma

Cutaneous fibrous histiocytoma, also known as dermatofibroma, is a common benign tumor of the skin that presents as an indurated nodule [8]. It is composed of a mixture of fibroblastic and histiocytic cells [10]. On the other hand, fibrosarcoma of bone is a malignant neoplasm that lacks significant differentiation towards any specific cell type, including fibrous or histiocytic cells [6].

Characteristics of Cutaneous Fibrous Histiocytoma

Cutaneous fibrous histiocytoma typically presents as a solitary firm nodule in the skin, with ill-defined borders and a red or purple coloration [1]. The tumor is usually asymptomatic and can be found on any part of the body. Histologically, it is characterized by a storiform pattern of spindle-shaped cells with palely staining nuclei [9].

Fibrohistiocytic Tumors

Fibrohistiocytic tumors are a group of heterogeneous lesions that share morphological features of histiocytes and fibroblasts on light microscopy [13]. They can be benign, intermediate, or malignant in nature. The term "fibrohistiocytic" is a descriptive designation without histogenetic connotation for this group of tumors.

Malignant Fibrous Histiocytoma

Malignant fibrous histiocytoma (MFH) is the most common soft-tissue sarcoma in late adult life, originating from mesenchymal cells [5]. It frequently occurs in the extremities and can be characterized by a storiform pattern of spindle-shaped cells with palely staining nuclei.

Atypical Fibrous Histiocytoma

Atypical fibrous histiocytoma is a rare variant of cutaneous fibrous histiocytoma that presents as a solitary firm nodule in the skin [15]. It can be characterized by a storiform pattern of spindle-shaped cells with palely staining nuclei and focal positivity for CD68.

References:

[1] - Context result 8 [5] - Context result 5 [6] - Context result 6 [9] - Context result 9 [13] - Context result 13 [15] - Context result 15

Based on the provided context, here are the signs and symptoms of an obsolete cutaneous fibrohistiocytic neoplasm:

• The overlying skin may appear red or red-brown in color, but occasionally may appear black [1].
• A central depression within the lesion (dimple sign) can be elicited [1].

It's worth noting that these signs and symptoms are likely to be associated with a specific type of cutaneous fibrohistiocytic neoplasm, which is now considered obsolete. The context suggests that this type of neoplasm has been largely replaced by more recently characterized soft tissue neoplasms.

References: [1] - A cutaneous fibrous histiocytoma is a common indurated nodule of benign origin composed of a mixture of fibroblastic and histiocytic cells [3]. [2] - Central hemorrhage or cystic change is an occasional feature [4].

Based on the provided context, it appears that diagnostic tests for cutaneous fibrohistiocytic neoplasms have evolved over time.

Immunohistochemical and Molecular Features

The pertinent immunohistochemical and molecular features of each entity are described in the medical literature [2]. These features can help in the differential diagnosis of cutaneous fibrohistiocytic neoplasms. Specifically, CD68 and CD10 are less specific for fibrohistiocytic lineage [15], while factor XIIIa is positive and CD34 is negative, supporting a diagnosis of fibrous, fibrohistiocytic and myofibroblastic neoplasms [15].

Ancillary Tests

Careful attention to clinical and histologic features, along with judicious use of ancillary tests, generally allows for accurate diagnosis and classification of cutaneous fibrohistiocytic neoplasms [11]. This approach is essential in distinguishing between different types of tumors within this category.

Diagnostic Criteria

A crucial criterion for the diagnosis of dermatofibrosarcoma protuberans (DFSP) is the presence of a fibrosarcomatous component in at least 5% of the tumor's volume [7]. This diagnostic criterion is essential for accurate classification and management of DFSP.

Importance of Proper Diagnosis

Proper diagnosis is essential in ex-tremity soft tissue tumors, as 30% may be malignant or undergo malignant degeneration [5]. Magnetic resonance imaging with histopathological correlation can aid in the diagnosis and management of these tumors.

In summary, diagnostic tests for cutaneous fibrohistiocytic neoplasms involve a combination of clinical and histologic features, along with ancillary tests such as immunohistochemistry and molecular analysis. Accurate diagnosis is crucial for proper classification and management of these tumors.

References:

[1] M Jozwik (2024) - Dermatofibrosarcoma protuberans (DFSP) [2] The pertinent immunohistochemical and molecular features [3] G Ji (2016) - Pathology diagnosis confirmed MFH [4] P Meister (1988) - Differential diagnosis can be helped by histochemical methods [5] Proper diagnosis is essential in ex-tremity soft tissue tumors [7] M Jozwik (2024) - After Enzinger and Weiss, an important criterion of the diagnosis [11] In conclusion, cutaneous fibrohistiocytic neoplasms are a diverse category of tumours [15] Skin nonmelanocytic tumor Fibrous, fibrohistiocytic and myofibroblastic neoplasms

Based on the provided context, it appears that there are various treatment options for cutaneous fibrohistiocytic neoplasms, including:

• Surgery: Mohs micrographic surgery or wide local excision is considered the treatment of choice for fibrohistiocytic tumors with metastatic potential, such as atypical fibroxanthoma (AFX) and cutaneous undifferentiated pleomorphic sarcoma (cUPS) [5].
• Chemotherapy: Chemotherapy, specifically ifosfamide and doxorubicin, can effectively reduce the tumor size of local recurrence or lymph node metastasis in some cases [14].
• Targeted therapy: Imatinib has been reported to decrease tumor size preoperatively and improve postsurgical aesthetic appearance and minimize functional impairment [15].

However, it's essential to note that these treatment options may not be relevant for all types of cutaneous fibrohistiocytic neoplasms. For instance:

• Atypical fibroxanthoma (AFX): While surgery is a common treatment, there is no consensus on the optimal therapy, and chemotherapy or targeted therapy might not be necessary in some cases [6].
• Cutaneous undifferentiated pleomorphic sarcoma (cUPS): Surgery with wide local excision or Mohs micrographic surgery is recommended, but chemotherapy or targeted therapy may be considered for metastatic disease [5].

It's also worth mentioning that the treatment landscape for cutaneous fibrohistiocytic neoplasms might have evolved since the provided context was last updated. Therefore, it's crucial to consult with a healthcare professional for personalized advice and the most up-to-date information on available treatments.

References:

[5] - Mohs micrographic surgery or wide local excision is the treatment of choice for fibrohistiocytic tumors with metastatic potential. [6] - Atypical fibroxanthoma (AFX) has no consensus on optimal therapy, but surgery is a common treatment. [14] - Chemotherapy can effectively reduce tumor size in some cases. [15] - Imatinib decreases tumor size preoperatively and improves postsurgical aesthetic appearance.

Differential Diagnosis of Obsolete Cutaneous Fibrohistiocytic Neoplasms

Cutaneous fibrohistiocytic neoplasms are a diverse group of tumors that resemble fibroblasts and histiocytes. However, they do not show a well-defined lineage or cell of origin. When diagnosing these neoplasms, it is essential to consider their clinical and histologic features, as well as differential diagnoses.

Common Differential Diagnoses

• Dermatofibrosarcoma protuberans (DFSP): This is a type of skin cancer that can be mistaken for cutaneous fibrohistiocytic neoplasms. DFSP typically has lower mitotic activity compared to other types of sarcomas.
• Malignant fibrous histiocytoma (MFH): Also known as undifferentiated pleomorphic sarcoma, MFH is a type of cancer that can be difficult to distinguish from cutaneous fibrohistiocytic neoplasms. However, it tends to have higher mitotic activity and more aggressive behavior.
• Nodular fasciitis: This is a benign tumor that can be mistaken for cutaneous fibrohistiocytic neoplasms due to its similar histologic features.
• Lipoma: A type of fatty tumor that can be confused with cutaneous fibrohistiocytic neoplasms, especially when they are located in the skin.

Other Differential Diagnoses

• Histoid leprosy: This is a rare form of leprosy that can be mistaken for cutaneous fibrohistiocytic neoplasms due to its similar histologic features.
• Xanthoma: A type of tumor composed of lipid-laden cells, which can be confused with cutaneous fibrohistiocytic neoplasms.

Key Features to Consider

When diagnosing obsolete cutaneous fibrohistiocytic neoplasms, it is essential to consider the following key features:

• Clinical presentation: The age and sex of the patient, as well as the location and size of the tumor.
• Histologic features: The presence or absence of mitotic activity, cellular atypia, and other histologic characteristics.
• Immunohistochemical staining: The use of specific antibodies to identify the cell type and lineage.

References

• Luzar B & Calonje E (2010) Histopathology56, 148–165 Cutaneous fibrohistiocytic tumours – an update.
• ICD-11: 2F23.0 - dermatofibroma
• Dermatofibrosarcoma protuberans (DFSP): Lower mitotic activity

Note: The above information is based on the provided context and may not reflect the most up-to-date or comprehensive information on this topic.