posterior uveal melanoma

Common Signs and Symptoms of Posterior Uveal Melanoma

Posterior uveal melanoma, a type of eye cancer, can cause various signs and symptoms that may indicate its presence. Here are some common ones:

• Decrease in visual acuity: A decrease in vision or blurry vision in the affected eye is one of the earliest signs of posterior uveal melanoma [6].
• Subclinical macular edema: The first sign may be a decrease in visual acuity due to subclinical macular edema, which can progress to proliferative retinopathy [6].
• Vision loss: Vision loss or blindness in the affected eye is a common symptom of posterior uveal melanoma, occurring in 68% of patients at 5 years after treatment [7].
• Blurred vision or double vision: Blurred vision or double vision in the affected eye can also be a sign of posterior uveal melanoma [9].
• Scotoma (blind spot): A blind spot or scotoma in the affected eye is another symptom that may indicate the presence of posterior uveal melanoma [9].

Other Possible Signs and Symptoms

In addition to these common signs and symptoms, other possible indicators of posterior uveal melanoma include:

• Neovascularization of the iris: The growth of new blood vessels on the surface of the iris can be a sign of posterior uveal melanoma [5].
• Dilated episcleral sentinel vessels: Dilated veins on the white part of the eye (sclera) may also indicate the presence of posterior uveal melanoma [5].

It's essential to note that these signs and symptoms can also be caused by other conditions, so a proper diagnosis by an eye specialist is necessary for accurate identification of posterior uveal melanoma.

Diagnostic Tests for Posterior Uveal Melanoma

Posterior uveal melanoma (PUM) diagnosis involves a combination of clinical examination, imaging tests, and sometimes biopsy. The primary goal is to confirm the presence of a tumor in the eye's posterior segment.

• Clinical Examination: A thorough eye exam by an ophthalmologist is essential for diagnosing PUM. This includes examining the outside of the eye for enlarged blood vessels that may indicate a tumor inside the eye, followed by a detailed examination using instruments such as slit-lamp biomicroscopy or indirect ophthalmoscopy [3][5].
• Ultrasound: Ultrasound is a primary diagnostic test that confirms the diagnosis of melanoma. It helps determine the size (thickness and basal dimension), extraocular extension (such as scleral nodules), and growth during follow-up of a suspicious nevus/small melanoma [2].
• Biomicroscopy and Indirect Ophthalmoscopy: These techniques are used to examine the eye's interior, providing critical information for diagnosis. Biomicroscopy involves using a microscope to examine the eye's anterior segment, while indirect ophthalmoscopy uses a condensing lens to magnify the image [1][5].
• Fine-needle Biopsy: This technique may be used to obtain tissue samples from the tumor for further examination and confirmation of the diagnosis [6].

Additional Diagnostic Tools

Other diagnostic tools that may be employed in diagnosing posterior uveal melanoma include:

• Optical Coherence Tomography (OCT): OCT can help determine the presence and characteristics of tumors, particularly those affecting the retina or optic nerve [9].
• Anterior Segment Ocular Coherence Tomography: This technique is used to examine the anterior segment of the eye, which may be affected in cases of PUM [6].

Prognostic Tests

In recent years, prognostic tests have been developed to more accurately assess a uveal melanoma tumor's biology and likelihood of spreading. Several factors have been historically associated with higher risk of metastasis, including large tumor size, location, orange pigment overlying the tumor, and older age [14].

References:

[1] by B Tarlan · 2016 · Cited by 132 [2] This is the primary diagnostic test that confirms the diagnosis of melanoma. [3] by PV Foti · 2021 · Cited by 51 [5] by B Tarlan · 2016 · Cited by 132 [6] Fine-needle Biopsy [9] Posterior Uveal Melanoma: Diagnostic Approaches [14] In recent years, prognostic tests have been developed to more accurately assess a uveal melanoma tumor’s biology and likelihood of spreading.

Posterior Uveal Melanoma Differential Diagnosis

The differential diagnosis of posterior uveal melanoma involves a range of conditions that can mimic the clinical presentation of this type of cancer. According to various studies, the following are some of the key differential diagnoses:

• Suspicious choroidal nevus: This is one of the most common differential diagnoses for posterior uveal melanoma, accounting for approximately 26.5% of cases [1].
• Disciform degeneration: This condition can also be mistaken for posterior uveal melanoma, with a reported incidence of around 12.5% [1].
• Peripheral disciform lesions: These are another type of differential diagnosis that can present similarly to posterior uveal melanoma [1].
• Uveal hemangioma: This is a benign vascular tumor that can be mistaken for posterior uveal melanoma, particularly in cases where the lesion is large and has irregular margins [6].
• Melanocytoma: This is a rare type of pigmented tumor that can be confused with posterior uveal melanoma due to its similar appearance on imaging studies [6].
• Choroidal metastasis: In some cases, posterior uveal melanoma may be mistaken for choroidal metastasis from another primary cancer, particularly in patients with a history of cancer elsewhere in the body [7].

Clinical Evaluation and Imaging Studies

The differential diagnosis of posterior uveal melanoma requires careful clinical evaluation and imaging studies to rule out these other conditions. A systematic diagnostic approach is recommended, which includes localization of the lesion within the various ocular tissues, identification of secondary effects in adjacent tissues, expert interpretation of imaging studies, and, in selected cases, tumor biopsy [15].

References

[1] Shields JA, Augsburger JJ, Brown GC, Stephens RF. The differential diagnosis of posterior uveal melanoma. Ophthalmology 1980;87:518-22.

[6] Mafee MF. Uveal melanoma, choroidal hemangioma, and simulating lesions. Role of MR imaging. Radiol Clin North Am 1998;36(6):1083-99.

[7] Rennie IG. The differential diagnosis of posterior uveal melanomas. Eye (Lond) 2002 Jul;16(4):325-46.

[15] Mafee MF, et al. The differential diagnosis of uveal tumors includes a variety of tumors and several nonneoplastic entities. A systematic diagnostic approach is required...