Renal Cell Carcinoma Metastasizing to Oral Soft Tissues: Systematic Review

Background  Renal cancer metastasis to oral region is very rare. Studies have been published analyzing the cases of metastatic tumors to the oral cavity by many researchers. Very few research studies have been conducted till date to analyze the renal cancer metastasis as the sole primary source to the oral soft tissues. The goal of this study was to examine the published cases of oral soft tissue metastasis from renal cell carcinoma as the only primary source from 1911 to 2022. Materials and Methods  An electronic search of the published literature was performed without publication year limitation in PubMed/Medline, Scopus, Google Scholar, Web of Science, Science Direct, Embase, and Research Gate databases, using mesh keywords like ("Renal cancer," or "Renal carcinoma" or "Renal cell cancer" or "Renal cell carcinoma"), and ("Metastasis" or "Metastases"), and ("Oral soft tissues" or "Tongue" or "Palate" or "Tonsil" or "Buccal mucosa" or "Salivary glands"). We also searched related journals manually and the reference lists. Results  Our research revealed a total of 226 relevant articles with 250 patients. Parotid glands and tongue were the most common sites of metastasis. 23% patients died with a survival time of 10 days to 4 years. Conclusions  Oral soft tissue metastasis from renal cell carcinoma has a bad prognosis. More cases need to be published in order to raise awareness of these lesions.