Rare Gingival Metastasis Occurring After Conversion Therapy Followed by Resection of Initially Unresectable Hepatocellular Carcinoma: A Case Report.

Gingival metastases from hepatocellular carcinoma (HCC) are exceedingly rare and highly prone to be misdiagnosed without biopsy. Here, we report an initially unresectable HCC patient who received effective conversion therapy but discovered gingival metastasis within one-month post-hepatectomy. A 53-year-old male with a huge liver tumor diagnosed as unresectable HCC received conversion therapy of hepatic arterial infusion chemotherapy (HAIC) combined with lenvatinib and tislelizumab. During the conversion therapy, he experienced sore gingiva which was regarded as a side effect of lenvatinib. Considering the significant shrinkage of tumor after 10-month treatment, salvage resection was conducted with negative margin and no postoperative complications. Gingival oligometastases were identified and resected half month after surgery. Throughout the 1-year follow-up period, the patient remained alive; however, there was a recurrence of the gingival metastasis at the same site six months postoperatively. Hence, clinicians should regard gingival swelling and pain not merely as potential adverse events of conversion therapy but also as potential indicators of gingival metastasis.