Microwave ablation (MWA) is a widely used treatment for liver metastases, particularly for lesions smaller than 3 cm. Although generally safe, rare complications such as segmental or lobar portal vein thrombosis (PVT) can occur. We present a unique case of tumor-like focal fat deposition in the left hepatic lobe following left PVT, a rare complication of MWA, in a 59-year-old female with pancreatic adenocarcinoma liver metastasis. Post-ablation imaging revealed geographic-shaped areas of focal hepatic steatosis confined to the left lobe, accompanied by left PVT. Dual-echo MRI, a routine but highly effective imaging sequence for liver fat characterization, was instrumental in distinguishing benign fat deposition from tumor recurrence. This case highlights the importance of recognizing focal hepatic steatosis as a rare but significant complication of MWA and PVT, with implications for clinical management and follow-up strategies.