Uveal melanoma metastasizes almost exclusively to the liver (90% of metastases). The mechanism that explains liver tropism includes which recently identified pathway?
- A Hematogenous spread through portal venous circulation
- B GNAQ/GNA11 mutations activate MEK/ERK signaling promoting hepatic endothelial attachment
- C Monosomy 3 directs tumor cells to hepatic sinusoids via BAP1 loss ✓
- D P16 (CDKN2A) deletion allows hepatic micrometastasis formation specifically
Explanation
Uveal melanoma (UM) liver-predominant metastasis is linked to loss of BAP1 (BRCA1-associated protein 1), which occurs with monosomy 3. BAP1 loss in uveal melanoma cells may create a pre-metastatic niche in liver by altering circulating immune-modulatory factors. Monosomy 3 + BAP1 loss + 8q gain constitute the highest-risk genomic signature for metastasis. GNAQ/GNA11 mutations are present in ~85% of UM and drive primary tumorigenesis via PKC/MEK signaling but are not specific to liver tropism. Liver tropism is attributed to CXCL12/CXCR4 axis, hepatic endothelial receptor expression, and BAP1-mediated immune privilege.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.