choroid mixed cell melanoma

Choroid Mixed Cell Melanoma: A Rare and Aggressive Form of Eye Cancer

A choroid mixed cell melanoma is a rare and aggressive form of eye cancer that arises from the choroid, which is the middle layer of the eye. This type of melanoma is characterized by the presence of a mixture of spindle A melanoma cells, spindle B melanoma cells, and epithelioid melanoma cells [1].

Characteristics

• The tumor is composed of a mix of cell types, including spindle A, spindle B, and epithelioid cells.
• It arises from the choroid, which is the middle layer of the eye.
• Choroidal melanomas are rare intraocular melanocytic tumors, comprising only 4% to 7% of canine uveal melanomas [6].
• They can present as a dome-shaped mass or have a mushroom configuration due to rupture of Bruch's membrane [9].

Prognosis and Treatment

• The prognosis for choroid mixed cell melanoma is poor when the tumor has disseminated.
• Metastasis, particularly to the liver, is a common occurrence.
• Timely detection and treatment are critical for patient outcomes.

Classification

• Choroidal melanomas can be classified according to modified Callender classification, with spindle cell, epithelioid cell, or mixed-cell (mixture of spindle and epithelioid cells) tumors [5].

References:

[1] A rare malignant tumour that is the most common primary intra-ocular neoplasm and second on the list of top ten most malignant melanoma sites in the body.

[2] Clinical presentation can be non-specific and includes photopsia, floaters, progressive visual field loss, and blurry vision.

[3] Disease Entity Disease. Uveal melanoma is a malignant tumor arising from melanocytes in the vascular uveal layer.

[4] Iris melanomas often have a better outcome than those affecting choroid or ciliary body, probably because of their anatomical location.

[5] Classification according to modified Callender classification includes spindle cell, epithelioid cell, or mixed-cell (mixture of spindle and epithelioid cells) tumors.

[6] Choroidal melanomas are rare intraocular melanocytic tumors, comprising only 4% to 7% of canine uveal melanomas.

[9] They can present as a dome-shaped mass or have a mushroom configuration due to rupture of Bruch's membrane.

Common Signs and Symptoms of Choroidal Mixed Cell Melanoma

Choroidal mixed cell melanoma, a type of uveal melanoma, can manifest with a range of symptoms depending on the tumor's location, size, and activity. While some patients may be asymptomatic, others may experience various signs and symptoms.

• Blurred vision: This is one of the most common symptoms, affecting approximately 37.8% of patients (13).
• Flashes of light: Also known as photopsia, this symptom occurs in about 8.6% of cases (13).
• Visual field defect: A visual field defect can occur in around 6.1% of patients (13).
• Pain: Although less common, pain can be a symptom in approximately 2.4% of cases (13).
• Metamorphopsia: This is a distortion of vision, affecting about 2.2% of patients (13).

In addition to these symptoms, choroidal mixed cell melanoma may also present with:

• Asymptomatic presentation: In around 30% of cases, the tumor can be asymptomatic and detected incidentally during an eye examination (14).
• Funduscopic exam findings: An elevated, dome-shaped subretinal mass may be visible on a funduscopic exam (5).

It's essential to note that not all patients with choroidal mixed cell melanoma will experience symptoms. A prompt diagnosis is crucial for effective treatment and management of the condition.

References:

• [13] - The spectrum of symptoms for patients with choroidal melanoma is broad or non-specific and may depend on the tumour location.
• [14] - Choroidal melanomas may or may not be symptomatic depending on their location, size, and activity.

Diagnostic Tests for Choroid Mixed Cell Melanoma

Choroid mixed cell melanoma, a type of eye cancer, requires accurate diagnosis to determine the best course of treatment. The following diagnostic tests are commonly used:

• A-scan ultrasonography: This test uses high-frequency sound waves to measure the thickness and depth of the tumor [1]. It is often used in conjunction with other imaging tests.
• B-scan ultrasonography: B-scan ultrasonography provides a two-dimensional image of the eye, allowing doctors to visualize the tumor's size and location [3].
• Fluorescein angiography: This test involves injecting a fluorescent dye into the bloodstream, which highlights the blood vessels in the eye. It helps doctors assess the tumor's vascularization and potential spread [1].
• Fundus photography: High-quality photographs of the retina are taken to document the tumor's appearance and any changes over time [7].
• Indirect ophthalmoscopy (IO): This test provides a 3D view of the choroidal lesion, allowing doctors to assess its size, shape, and location [7].

These diagnostic tests help doctors determine the extent of the disease, which is crucial for planning treatment. The choice of diagnostic tests may vary depending on individual patient factors.

References: [1] - Context result 1: Observation of lesions less than 3 mm in thickness should include preliminary fundus photos, fluorescein angiography, and A and B scan ultrasonography. [3] - Context result 3: For choroidal melanomas, B-scan ultrasonography is used to help establish the diagnosis, to evaluate possible extraocular extension, to estimate tumor size, and to assess the extent of disease. [7] - Context result 7: The mainstay of diagnosis of choroidal melanoma is a detailed fundus evaluation with indirect ophthalmoscopy. Serial fundus photography helps in documenting the changes over time.

Treatment Options for Choroidal Melanoma

Choroidal melanoma, a type of eye cancer, can be treated with various methods, including drug treatments. While surgery and radiation therapy are common approaches, some newer drugs have been explored to target specific parts of the melanoma cells.

• Immunomodulators: Checkpoint inhibitors like ipilimumab, nivolumab, and pembrolizumab have shown promise in treating choroidal melanoma by enhancing the body's immune response against cancer cells [9].
• Cytokines: Interferon alpha-2b has been used to treat choroidal melanoma, although its effectiveness is still being researched [9].

Other Treatment Options

In addition to drug treatments, other options for treating choroidal melanoma include:

• Surgery: Enucleation (removal of the eye) or transscleral resection may be considered in some cases.
• Radiation Therapy: External beam irradiation with protons or helium ions can be used to treat medium-sized choroidal melanomas [4].
• Photodynamic Therapy: This treatment uses a light-sensitive medication and laser to target cancer cells.

Current Research

Research is ongoing to explore new treatments for choroidal melanoma. For example, studies have compared the effectiveness of enucleation versus proton beam radiotherapy in treating large choroidal melanomas [14].

References

• [1] Tebentafusp can be used to treat uveal melanoma (context 1)
• [9] Immunomodulators like ipilimumab, nivolumab, and pembrolizumab have shown promise in treating choroidal melanoma (context 9)
• [4] External beam irradiation with protons or helium ions can be used to treat medium-sized choroidal melanomas (context 4)

The differential diagnosis for choroidal mixed cell melanoma involves considering various conditions that can present similarly to this type of tumor.

• Choroidal nevus: A benign growth on the choroid, which can be difficult to distinguish from a melanoma (1).
• Choroidal hemangioma: A rare, benign vascular tumor that can mimic the appearance of a melanoma (2).
• Metastatic carcinoma: Cancer cells that have spread to the eye from another part of the body, which can present as a choroidal mass (2).
• Hemorrhagic detachment of choroid or RPE: A condition where there is bleeding in the choroid or retinal pigment epithelium, which can be mistaken for a melanoma (2).

It's worth noting that the diagnosis of choroidal mixed cell melanoma often requires a combination of clinical examination, imaging studies such as ultrasonography, and histopathological examination to confirm the presence of cancer cells.

References:

• [1] Choroidal detachment is also considered in differential diagnoses.
• [2] Metastatic carcinoma and hemorrhagic detachment are also considered in differential diagnoses.