epithelioid cell melanoma

Epithelioid Cell Melanoma: A Rare Variant of Cutaneous Melanoma

Epithelioid cell melanoma (ECM) is a rare variant of cutaneous melanoma, typically characterized by large malignant cells with abundant eosinophilic cytoplasm and enlarged round to oval-shaped nuclei [7]. These cells often lack cohesiveness and demonstrate marked pleomorphism, including the formation of multinucleated tumor cells [15].

Histological Features

The histologic descriptions of ECM include:

• Large epithelioid melanoma cells with eccentrically placed nuclei
• Prominent nucleoli and occasional intranuclear pseudoinclusions
• Cells resembling epithelium due to abundant eosinophilic cytoplasm and enlarged round to oval-shaped nuclei [14]
• Epithelioid melanoma cells often lack cohesiveness and demonstrate marked pleomorphism, including the formation of multinucleated tumor cells [15]

Cytological Patterns

ECM can be categorized into two major types: epithelioid and spindle cells. Epithelioid cells are large and round with abundant eosinophilic cytoplasm, prominent vesicular nuclei, and large nucleoli [2]. They most commonly arise in superficial spreading and nodular melanomas.

Clinical Significance

ECM is a rare variant of cutaneous melanoma, but it can be aggressive and have early metastasis to lymph nodes [5]. Sentinel node staging is recommended only for "unclassified atypical dermal" tumors, which may include ECM [12].

Immunohistochemical Markers

Tyrosinase is a sensitive and specific marker for the diagnosis of melanoma, although it can also be present in other types of cancer with melanocytic lineage [13].

Common Signs and Symptoms of Epithelioid Cell Melanoma

Epithelioid cell melanoma, also known as epithelioid melanoma, is a rare type of skin cancer that can be challenging to diagnose. The symptoms and signs of this condition are often similar to those of other types of skin cancers or benign growths. Here are some common signs and symptoms associated with epithelioid cell melanoma:

• Asymmetrical Lesion: A large lesion that is asymmetrical in shape, which may also itch, bleed, ulcerate, or develop satellite lesions [1].
• Notable Lump: A noticeable lump or nodule under the skin, often firm to the touch and painless [7].
• Swelling: Swelling around the affected area, which can be accompanied by redness and warmth.
• Change in Size, Shape, Color: The lesion may change in size, shape, color, or texture over time, which can be a sign of recent growth or transformation [6].

It's essential to note that these symptoms can also be indicative of other skin conditions. A definitive diagnosis of epithelioid cell melanoma requires a biopsy and histopathological examination.

References:

[1] Context result 1 [6] Context result 6 [7] Context result 7

Treatment Options for Epithelioid Cell Melanoma

Epithelioid cell melanoma, a subtype of melanoma, requires effective treatment to manage the disease. According to various medical sources [1][2], the following drug treatments are commonly used:

• Immunotherapy: This type of therapy boosts the body's immune system to fight cancer cells. Pembrolizumab (Keytruda) and nivolumab (Opdivo) are FDA-approved immunotherapies for melanoma, including epithelioid cell melanoma [1].
• Targeted Therapy: Targeted therapies specifically target the genetic mutations that drive cancer growth. Vemurafenib, dabrafenib, and encorafenib are three drugs used to treat BRAF V600E-mutated melanoma, which includes epithelioid cell melanoma [6].
• Chemotherapy: Chemotherapy involves using medications to kill cancer cells. Cisplatin is a platinum derivative cis that has been used in chemotherapy for melanoma, including epithelioid cell melanoma [3].

Combination Therapy

In some cases, combination therapy may be recommended to achieve better treatment outcomes. For example, combining immunotherapy with targeted therapy or chemotherapy can lead to improved responses [13][14]. Amtagvi (lifileucel), a cellular therapy, has also been approved for the treatment of adult patients with epithelioid cell melanoma [10].

References

[1] - Immunotherapy Drugs for Melanoma [2] - Treatment Options for Epithelioid Cell Melanoma [3] - Cisplatin in Chemotherapy for Melanoma [6] - Vemurafenib, Dabrafenib, and Encorafenib for BRAF V600E-mutated Melanoma [10] - Amtagvi (Lifileucel) for Epithelioid Cell Melanoma [13] - Combination Therapy for Melanoma [14] - Improved Outcomes with Combination Therapy

The differential diagnosis for epithelioid cell melanoma, also known as amelanotic melanoma, can be quite challenging due to its non-specific presentation.

Common Differential Diagnoses

• Poorly differentiated carcinoma: This type of cancer can present with large, epithelioid cells and is often considered in the differential diagnosis for epithelioid cell melanoma [2].
• High-grade non-Hodgkin lymphoma: The presence of large, epithelioid cells with multinucleation can also suggest a diagnosis of high-grade non-Hodgkin lymphoma [6, 12].
• Epithelioid schwannoma: This rare tumor can present with epithelioid cells and is often considered in the differential diagnosis for epithelioid cell melanoma [4, 10].
• Clear cell sarcoma: This type of cancer can also present with epithelioid cells and is often considered in the differential diagnosis for epithelioid cell melanoma [8, 10].

Other Considerations

• Perivascular epithelioid cell tumor (PEComa): This rare tumor can present with perivascular epithelioid cells and is often considered in the differential diagnosis for epithelioid cell melanoma [5, 15].
• Poorly differentiated cutaneous angiosarcoma: This type of cancer can also present with epithelioid cells and is often considered in the differential diagnosis for epithelioid cell melanoma [14].

Key Features to Consider

When considering a diagnosis of epithelioid cell melanoma, it's essential to look for key features such as:

• Melan-A/MART-1 positivity: The presence of Melan-A/MART-1 positivity in some cells can suggest a diagnosis of epithelioid cell melanoma [12].
• S-100 positivity: The presence of S-100 positivity in most tumor cells can also suggest a diagnosis of epithelioid cell melanoma [12].

It's worth noting that the differential diagnosis for epithelioid cell melanoma can be quite broad, and a thorough evaluation by an experienced pathologist is often necessary to arrive at a definitive diagnosis.