P5997 - The Eye That Struck the Liver: A Rare Case of Uveal Melanoma Presenting as a Solitary Hepatic Mass

Alexa Plato, MD¹, Cheng-Hung Tai, MD¹, Raquel Rozner, MD²
1Yale New Haven Health, Bridgeport Hospital, Bridgeport, CT; 2Yale School of Medicine, Gastroenterology Associates, PC, Northeast Medical Group/Yale New Haven Health, Stratford, CT

Introduction: Uveal melanoma is a rare but distinct subtype of melanoma with a marked predilection for

hepatic metastasis. Unlike cutaneous melanoma, it follows a unique molecular and metastatic

profile, often confounding the diagnosis when a primary lesion is not evident. Here we present a rare

case of presumed uveal melanoma discovered incidentally as an isolated hepatic mass in a

patient without prior melanoma history or detectable primary lesion.

Case Description/

Methods: A 58-year-old male with history of celiac disease was noted to have elevated AST/ALT and

microcytic anemia (Hb 12.9 g/dL). Workup revealed an 8 cm hepatic mass on MRI. Core biopsy

confirmed metastatic melanoma. The patient denied prior cutaneous or mucosal lesions.

Colonoscopy and dermatologic total body skin exam were unremarkable. Ophthalmologic

evaluation was initiated, though no classic GNAQ or GNA11 mutations were found on early

molecular profiling. CT CAP and MRI brain showed no other significant disease. Given the

liver-only pattern of metastasis and absence of cutaneous/mucosal primaries, the diagnosis of

GNAQ/GNA11-wild-type uveal melanoma was favored. The patient was enrolled in an

immunotherapy trial.

Discussion: Over 90% of uveal melanomas metastasize to the liver, making it the principal site of distant

disease. This hepatic tropism is so specific that isolated liver involvement in a melanoma of

unknown primary often implicates a uveal origin—even without a detected ocular lesion. While

GNAQ and GNA11 mutations are present in ~83–95% of uveal melanomas, a small but

meaningful subset (~5–17%) is wild-type for both. These cases may harbor alternative mutations

(CYSLTR2, PLCB4, EIF1AX, SF3B1) or none at all, underscoring the diagnostic difficulty.

Importantly, absence of GNAQ/GNA11 does not exclude uveal origin, especially in patients

lacking skin or mucosal findings. The absence of ocular findings may reflect a regressed or

undetected primary tumor, a phenomenon seen in rare metastatic uveal melanoma cases. Primary

hepatic melanoma remains a theoretical possibility but lacks convincing evidence and is

considered vanishingly rare.

This case highlights the diagnostic nuances of hepatic melanoma metastases in the absence of

cutaneous or mucosal primaries, particularly in GNAQ/GNA11-negative disease. It emphasizes

the need for high clinical suspicion, interdisciplinary collaboration, and consideration of uveal

melanoma in solitary liver lesions, even when conventional genetic markers are absent.


Figure: Image 1: Liver Mass on MRI


Figure: Image 2: Melanoma (Left) within Liver (Right)

Disclosures:
Alexa Plato indicated no relevant financial relationships.
Cheng-Hung Tai indicated no relevant financial relationships.
Raquel Rozner indicated no relevant financial relationships.

Alexa Plato, MD¹, Cheng-Hung Tai, MD¹, Raquel Rozner, MD². P5997 - The Eye That Struck the Liver: A Rare Case of Uveal Melanoma Presenting as a Solitary Hepatic Mass, ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.