Although bone metastasis of a malignant tumor is not rare, it is generally thought that intraoral maxillary metastasis from other organs is rare.
The authors experienced a case of mandibular metastasis of the renal cancer, on which a report is made here with literature consideration thereof.
Patient: S.S. 49-year-old man (office man)
Initial medical examination: November 24, 1981
Chief complaint: Formation of a painless tumor at his left mandibular mental foramen region
Family history: Pneumonia (20 years ago) and sciatica (12 years ago)
Present illness: About a month ago, a thumb-sized swelling was noticed at his left cheek, and he consulted a town doctor for lower lip paresthesia. Chemotherapy was performed for 10 days without symptomatic improvement and he came to our Department of Oral Surgery.
Present examination: The patient had moderate general physique and eutrophia. His countenance was nearly symmetrical, however, a thumb-sized elastic and hard tumor was palpable at his left mental foramen region. On the affected side intraorally, there observed a defect of the mandibular molar and a tumor at the dental root of the mandibular premolar. There was neither gingival inflammation nor swelling of its attached submandibular lymph node.
Results of clinical examinations: X-ray exploration revealed a thumb-sized and comparatively well-defined bone resorption shadow, centering around his left mental foramen region. There were no abnormal values obtained from general blood examinations.
Treatment: The tumor suspected of mandibular cyst was extirpated under general anesthesia.
Results of histopathological examination: The extirpated multinodular solid tumor, covered with connective tissues, was diagnosed pathologically as a clear cell carcinoma with a honeycomb-like structure which was delimited by the abundant strome and blood vessels.
Postoperatively, the intraoral wound showed good healing, process however, the lung or kidney was suspected as the primary site of this tumor, and a co-exploration by the Department of Surgery and the Department of Urology and a detailed examination detected left renal cancer of the patient who was then transferred to be radically operated for renal cancer.
Literature examination of such cases revealed that intraoral bone metastasis of renal cancer was rare. The treatment of intraoral metastatic cancer is usually perfomed at its relatively early phase and its prognosis was frequency poor depending on the result of the treatment for its primary focus.
