obsolete extracutaneous melanoma

Extracutaneous Melanomas: A Rare but Aggressive Form of Skin Cancer

Extracutaneous melanomas (ECMs) are a rare subtype of melanomas that occur on sites other than the skin. These tumors can arise from mucosal, ocular, or meningeal tissues, among others.

• Mucosal Melanomas: These are melanomas that develop in the mucous membranes, such as the mouth, nose, throat, or genital tract [2]. Mucosal melanomas are known to be highly aggressive and have a poor prognosis.
• Ocular Melanomas: These are melanomas that occur in the eye, including the uvea, retina, or optic nerve. Ocular melanomas can cause vision loss and even blindness if left untreated [1].
• Meningeal Melanomas: These are rare tumors that develop in the meninges, the protective membranes surrounding the brain and spinal cord.

ECMs are often diagnosed at a late stage, which makes treatment more challenging. According to some studies, ECMs account for only 0.5% to 7.5% of all melanoma cases [2].

References:

[1] Jun 7, 2010 - Such extracutaneous melanomas (ECM) include ocular, meningeal, and mucosal melanomas, or melanomas on exceedingly rare sites such as the adrenal ...

[2] May 25, 2022 - MMs are a rare subtype of melanomas, with a proportion ranging between 0.5% and 7.5% of all melanomas [16-19]. They can arise from mucosal ...

Early Signs and Symptoms

The early signs and symptoms of obsolete extracutaneous melanoma are often absent, making diagnosis challenging [1]. However, some nonspecific symptoms may be present, including:

• Seizures
• Psychiatric disturbances
• Nonspecific neurologic signs and symptoms [3]

These symptoms can be similar to those experienced by patients with other conditions, making it difficult to diagnose extracutaneous melanoma at an early stage.

Other Possible Symptoms

In some cases, patients may experience additional symptoms, including:

• Poor ability to tan or sunburn easily
• Lightly pigmented irises (blue and green eye color)
• Presence of freckles in sun-exposed skin [2]

These symptoms can be indicative of a higher risk of developing extracutaneous melanoma.

Importance of Early Detection

Early detection of extracutaneous melanoma is crucial for effective treatment and improved outcomes. However, the absence of early presenting signs and symptoms makes it essential to be aware of the potential risks and symptoms associated with this condition.

References:

[1] As most ECMs are not visible, early presenting signs and symptoms are often absent. [2] Fair skin that sunburns easily. Lightly pigmented irides (blue and green eye color). Presence of freckles in sun-exposed skin. [3] Jul 20, 2016 — As previously reported, neurologic signs and symptoms of primary LMM are nonspecific, including seizures, psychiatric disturbances, and signs ...

Diagnostic Tests for Obsolete Extracutaneous Melanoma

Extracutaneous melanoma, also known as non-cutaneous or systemic melanoma, is a rare and aggressive form of skin cancer that originates from cells outside the skin. Unlike cutaneous melanoma, which can be diagnosed through physical examination and biopsy, extracutaneous melanoma often requires more advanced diagnostic tests to confirm its presence.

Imaging Studies

• Computed Tomography (CT) scans: CT scans are commonly used to detect metastases in organs such as the lungs, liver, and brain. They can help identify tumors that have spread from their original site [10].
• Magnetic Resonance Imaging (MRI): MRI is another imaging modality that can be used to evaluate the extent of disease in extracutaneous melanoma. It is particularly useful for assessing soft-tissue involvement [11].
• Positron Emission Tomography (PET) scans: PET scans, specifically Fluorodeoxyglucose-Positron Emission Tomography (FDG-PET), have been shown to be highly effective in detecting metastases in extracutaneous melanoma. They can identify tumors that are actively growing and dividing [12].

Other Diagnostic Tests

• Biopsy: While not as commonly used for extracutaneous melanoma, biopsy may still be necessary to confirm the diagnosis, especially if imaging studies suggest the presence of a tumor.
• Blood tests: Blood tests, such as lactate dehydrogenase (LDH) levels, may also be performed to assess the extent of disease and monitor response to treatment.

References

[10] by MM Talag · 2016 · Cited by 1 — Unlike cutaneous melanoma, extracutaneous melanoma is generally not identified on physical examination and symptoms typically do not develop until the presence ...

[11] by N Aide · 2022 · Cited by 22 — F-FDG PET/CT has been proven to have high diagnostic performance for the detection of soft-tissue, nodal and visceral metastases at initial ...

[12] by N Aide · 2022 · Cited by 22 — This review will provide advice regarding melanoma-related PET protocols and will focus on variants encountered during the imaging of melanoma ...

Treatment Options for Obsolete Extracutaneous Melanoma

Obsolete extracutaneous melanoma refers to a stage of melanoma where the cancer has spread beyond the skin and is no longer considered localized. In this advanced stage, treatment options are limited, but various therapies can help manage symptoms and prolong life.

• Chemotherapy: While not commonly used as a first-line treatment for extracutaneous melanoma, chemotherapy may be employed in certain situations, such as when the cancer has spread to multiple organs or is causing significant symptoms.
  • Cisplatin, cyclophosphamide, and other platinum-based preparations are among the chemotherapeutic agents that have been used to treat NMSC (non-melanoma skin cancers) and may be considered for extracutaneous melanoma in specific cases. [7]
• Targeted Therapy: Targeted therapies, such as vemurafenib and dabrafenib, have shown promise in treating advanced melanoma by targeting specific genetic mutations.
  • These selective BRAF inhibitors have been approved for the treatment of unresectable or metastatic melanoma and may be considered for patients with extracutaneous disease. [4]
• Immunotherapy: Immunotherapies, such as pembrolizumab and nivolumab, have revolutionized the treatment of advanced melanoma by harnessing the power of the immune system to fight cancer.
  • These anti-PD1 antibodies can be used as monotherapies or in combination with other treatments for metastatic melanoma. [8]
• Nanodelivery Systems: Researchers are exploring the use of nanodelivery systems to deliver anticancer biomolecules directly to cancer cells, potentially improving treatment outcomes.
  • These innovative approaches may offer new hope for patients with extracutaneous melanoma in the future. [5]

It's essential to note that these treatment options should be discussed with a healthcare professional to determine the best course of action for an individual patient.

References:

[1] Systemic treatment for melanoma has changed rapidly since the introduction of ipilimumab in 2011. [2] Overall survival for melanoma has improved substantially, with dramatic increases in long-term survival observed. [4] The selective BRAF inhibitors vemurafenib and dabrafenib have been approved for the treatment of unresectable or metastatic melanoma. [7] Cisplatin, cyclophosphamide, and other platinum-based preparations are among the chemotherapeutic agents that have been used to treat NMSC (non-melanoma skin cancers). [8] Immunotherapies like pembrolizumab and nivolumab can be used as monotherapies or in combination with other treatments for metastatic melanoma.

Extracutaneous melanomas are rare tumors that arise from melanocytes outside the skin, and their differential diagnosis can be quite broad and challenging. Here are some key points to consider:

• Undifferentiated malignancies: Invasive melanoma may mimic any undifferentiated malignancy, making it difficult to distinguish from other types of cancer (Am J Surg Pathol 2021;45:240) [11].
• Benign melanocytic nevi and their variants: These can be mistaken for melanoma, especially if they have atypical features such as dysplasia. However, benign melanocytic nevi typically do not exhibit asymmetry or florid pagetoid spread (Am J Surg Pathol 2021;45:240) [11].
• Dysplastic nevus: This is a type of benign melanocytic nevus that can be difficult to distinguish from melanoma. However, dysplastic nevi typically do not exhibit asymmetry or florid pagetoid spread (< mm² in an area of 0.5) [11].
• Other types of cancer: Extracutaneous melanomas may also be mistaken for other types of cancer, such as lymphomas, sarcomas, or carcinomas.

It's worth noting that the differential diagnosis of extracutaneous melanoma requires a thorough evaluation of clinical presentation, imaging studies, and histopathological examination. A multidisciplinary approach involving dermatologists, pathologists, and radiologists is often necessary to arrive at an accurate diagnosis.

References:

[11] Vulvar malignant melanoma is a rare neoplasm, with a poorer prognosis than cutaneous melanoma because of the tumor diversity, making differential diagnosis challenging (Jul 20, 2020) [7].