Recently, several types of promising radiotherapy for oral cancer have been explored. Among these, intensity modulated radiotherapy（IMRT）, particle therapy, brachytherapy, and boron neutron capture therapy（BNCT）are reviewed here.
Radiotherapy has played an important role in the treatment of head and neck cancers including oral cancer. IMRT allows highly consistent dose distributions to target volumes of almost any shape. The primary benefit of IMRT is its potential for sparing the parotid gland, leading to reduction of xerostomia.
Particle therapy using protons or carbon ions is capable of delivering high-dose radiation to the tumor while minimizing the dose delivered to organs at risk. Regarding head and neck malignancies, particle therapy has been used mainly for radioresistant tumors such as mucosal malignant melanoma and adenoid cystic carcinoma, and favorable outcomes have been obtained. Among the patients with non-squamous cell carcinomas and sarcomas which comprise approximately 10％ of oral malignancies, inoperable cases may be candidates for particle therapy. In terms of radiation toxicities in the oral cavity such as mucositis/mucosal ulcer and osteonecrosis of the jaw, the excellent dose distribution of particle therapy is an advantage.
Brachytherapy is known as a suitable treatment for superficial type oral cancer. The treatment outcomes of 260 cancers in 255 patients who were treated at Tokyo Medical and Dental University Hospital were evaluated.
The 2-year local control rates of superficial type, infiltrative type, and exophytic type oral cancers were 90.9％, 78.9％, and 91.7％, respectively.
By BNCT, radiation can be selectively delivered to tumor cells. The treatment outcomes of 45 patients who have no treatment options at Kyoto University Research Reactor Institute and Japan Atomic Energy Agency were evaluated. Clinical response rates were 87％（CR: 51％, PR: 29％ and SD: 7％） and the 5-year OS rate was 30％.
For oral cancer, various radiotherapies play a central role in improving outcomes and reducing morbidities, especially in inoperable cases and in combination with surgery.

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The purposes of mandibular reconstruction are maintaining aesthetic and masticatory function. For the latter, occlusal contact on the healthy side is important; if the patient has no occlusal contact, masticatory function is poor.
Reconstruction with vascularized bone containing flap and implant-supported prostheses is the ideal approach for edentulous cases just after reconstruction, but the indications are restricted. Therefore, we must consider other methods that can be indicated for many cases.

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Speech and swallowing function are significantly impaired when excision is more than subtotal glossectomy. The purpose of reconstruction is to maintain the patient’s QOL by ensuring the airway, speech and swallowing function. Individual cases may not achieve the same results. The purposes of resection are: no recurrence, function preservation, and high reproducibility. Reconstruction is easy to predict because there is no recurrence, no postoperative irradiation and clear remaining function, and is considered a better technique overall.

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Thrombocytopenia is a hematological disorder frequently found in patients with chronic liver disease （CLD）. In September 2015, Lusutrombopag was approved because of its efficacy shown for improving thrombocytopenia in CLD patients scheduled for an elective open procedure. This drug is a thrombopoietin receptor agonist that has been shown to be a relatively safe and noninvasive platelet-increasing agent when given preoperatively to improve platelet count. Here, we report a patient with a lower gingival carcinoma and history of thrombocytopenia associated with hepatitis C who was given Lusutrombopag prior to surgery, with good results obtained. The patient was a 75-year-old woman. At our first consultation, a neoplastic lesion with a granular surface sized 30×20mm was observed in the right side of the lower gingiva. She had a history of hepatitis C; a hematological examination performed at the first consultation showed a platelet count of 65,000/μl, indicating a reduced count. On the basis of our diagnosis of right lower gingival carcinoma （cT2N0M0）, surgery was planned. The patient was administered Lusutrombopag （3 mg/day） from 11 days before the operation. Two days prior to the scheduled surgical procedures, the platelet count had elevated to 136,000/μl. The peri- and postoperative courses were favorable, without hemorrhage or thrombosis noted during or after surgery.

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In oral cancer, occult cervical lymph node metastasis typically becomes apparent within two years from the initial treatment of the primary tumor. However, the clinical appearance of occult cervical lymph node metastasis rarely occurs more than two years from the initial treatment. We report three cases of cervical lymph node metastasis appearing more than two years later.
All three cases had cervical lymph node metastasis: it appeared in a 38-year old female patient two years and six months after brachytherapy for tongue squamous cell carcinoma; in a 47-year old female patient at five years and eleven months after partial glossectomy followed by brachytherapy for tongue squamous cell carcinoma; and in a 57-year old male patient at five years and eleven months after partial glossectomy for tongue squamous cell carcinoma. It is impossible to predict the time when occult cervical lymph node metastasis will clinically appear. In order to detect it as soon as possible, long-term careful follow-up and education for patients on cervical lymph node metastasis are required.

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Myxolipma is an extremely rare subtype of lipoma; only 4 cases in the oral cavity have been reported so far in Japan. We herein report a case of a myxolipoma arising from the lateral border of the tongue in a 64-year-old male. The patient was referred to our hospital department with the chief complaint of swelling of the tongue. T1- and T2- weighted MRI clearly showed high signal intensity, with a tumor size of 11×9×11mm. The tumor was excised under general anesthesia. Histopathological examination showed proliferation of mature adipose cells, including myxoid-change. On the basis of the results of histopathological examination, we diagnosed a myxolipoma arising from the tongue. No evidence of any local recurrence was observed during the one-year follow-up period.

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